Monkeys show reduced Parkinsonian symptoms following a donor-matched iPS cell-based therapy. Misaki Ouchida, Center for iPS Cell Research and Application, Kyoto University

One of the last steps before treating patients with an experimental cell therapy for the brain is confirmation that the therapy works in monkeys. In its latest study, the Jun Takahashi lab shows monkeys with Parkinson's disease symptoms show significant improvement over two years after being transplanted neurons prepared from human iPS cells. The study, which can be read in Nature, is expected to be a final step before the first iPS cell-based therapy for a neurodegenerative disease.

Parkinson's disease degenerates a specific type of cells in the brain known as dopaminergic (DA) neurons. It has been reported that when symptoms are first detected, a patient will have already lost more than half of his or her DA neurons. Several studies have shown the transplantation of DA neurons made from fetal cells can mitigate the disease. The use of fetal tissues is controversial, however. On the other hand, iPS cells can be made from blood or skin, which is why Professor Takahashi, who is also a neurosurgeon specializing in Parkinson's disease, plans to use DA neurons made from iPS cells to treat patients.

"Our research has shown that DA neurons made from iPS cells are just as good as DA neurons made from fetal midbrain. Because iPS cells are easy to obtain, we can standardize them to only use the best iPS cells for therapy, " he said.

To test the safety and effectiveness of DA neurons made from human iPS cells, Tetsuhiro Kikuchi, a neurosurgeon working in the Takahashi lab, transplanted the cells into the brains of monkeys.

"We made DA neurons from different iPS cells lines. Some were made with iPS cells from healthy donors. Others were made from Parkinson's disease patients," said Kikuchi, who added that the differentiation method used to convert iPS cells into neurons is suitable for clinical trials.

It is generally assumed that the outcome of a cell therapy will depend on the number of transplanted cells that survived, but Kikuchi found this was not the case. More important than the number of cells was the quality of the cells.

"Each animal received cells prepared from a different iPS cell donor. We found the quality of donor cells had a large effect on the DA neuron survival," Kikuchi said.

To understand why, he looked for genes that showed different expression levels, finding 11 genes that could mark the quality of the progenitors. One of those genes was Dlk1.

"Dlk1 is one of the predictive markers of cell quality for DA neurons made from embryonic stem cells and transplanted into rat. We found Dlk1 in DA neurons transplanted into monkey. We are investigating Dlk1 to evaluate the quality of the cells for clinical applications."

Another feature of the study that is expected to extend to clinical study is the method used to evaluate cell survival in the host brains. The study demonstrated that magnetic resonance imaging (MRI) and position electron tomography (PET) are options for evaluating the patient post surgery.

"MRI and PET are non-invasive imaging modalities. Following cell transplantation, we must regularly observe the patient. A non-invasive method is preferred," said Takahashi.

The group is hopeful that it can begin recruiting patients for this iPS cell-based therapy before the end of next year. "This study is our answer to bring iPS cells to clinical settings," said Takahashi.

This article has been republished frommaterialsprovided byCIRA, Kyoto University. Note: material may have been edited for length and content. For further information, please contact the cited source.

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Monkeys With Parkinson's Disease Successfully Treated With Human Stem Cell Transplants - Technology Networks

IPS Cell Therapy Comments Off on Monkeys With Parkinson’s Disease Successfully Treated With Human Stem Cell Transplants – Technology Networks | September 1st, 2017

Stem cells and genome editing offer exciting opportunities within regenerative medicine. However, any clinical application of stem cells requires strict regulation to ensure that the cells are not exposed to animal derived products.

StemFit Basic02 is a xeno-free, defined medium for human pluripotent stem cell (hiPSC) culture that offers an effective solution for regenerative medicine research. This medium has been proven to effectively maintain Induced Pluripotent Stem (iPS) and Embryonic Stem (ES) cells under feeder-free conditions, during the reprogramming, expansion and differentiation phases of stem cell culture.

Specially formulated to enhance single cell expansion in the cloning step of stem cell genome editing, StemFit Basic02 offers superior and stable growth performance, high colony forming efficiency and robust scalable cell expansion. This ensures high karyotype stability over long periods and hence reproducible culture conditions.

StemFit cell culture media has been independently evaluated by CGT Catapult, an independent centre of excellence helping advance the UK cell and gene therapy industry. In these tests, StemFit not only delivered higher cell proliferation, but also showed characteristics such as homogeneity of gene expression compared with iPS cells cultured with 4 other media without any chromosomal abnormalities.

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Xeno-free Cell Culture Medium for Regenerative Medicine Research - Technology Networks

IPS Cell Therapy Comments Off on Xeno-free Cell Culture Medium for Regenerative Medicine Research – Technology Networks | September 1st, 2017

Stem cells and genome editing offer exciting opportunities within regenerative medicine.

However, any clinical application of stem cells requires strict regulation to ensure that the cells are not exposed to animal derived products.

Now Amsbio announces the availability of StemFit Basic02 feeder-free stem cell culture media.

StemFit Basic02 is a xeno-free, defined medium for human pluripotent stem cell (hiPSC) culture that offers an effective solution for regenerative medicine research.

This medium has been proven to effectively maintain Induced Pluripotent Stem (iPS) and Embryonic Stem (ES) cells under feeder-free conditions, during the reprogramming, expansion and differentiation phases of stem cell culture.

Specially formulated to enhance single cell expansion in the cloning step of stem cell genome editing, StemFit Basic02 offers superior and stable growth performance, high colony forming efficiency and robust scalable cell expansion.

This ensures high karyotype stability over long periods and hence reproducible culture conditions.

StemFit cell culture media has been independently evaluated by CGT Catapult, an independent centre of excellence helping advance the UK cell and gene therapy industry.

In these tests, StemFit not only delivered higher cell proliferation, but also showed characteristics such as homogeneity of gene expression compared with iPS cells cultured with four other media without any chromosomal abnormalities.

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Xeno-free cell culture medium for regenerative medicine research - Scientist Live

IPS Cell Therapy Comments Off on Xeno-free cell culture medium for regenerative medicine research – Scientist Live | September 1st, 2017

LONDON (Reuters)Scientists have successfully used reprogrammed stem cells to restore functioning brain cells in monkeys, raising hopes the technique could be used in future to help patients with Parkinsons disease.

Since Parkinsons is caused by a lack of dopamine made by brain cells, researchers have long hoped to use stem cells to restore normal production of the neurotransmitter chemical.

Now, for the first time, Japanese researchers have shown that human induced pluripotent stem cells (iPS) can be administered safely and effectively to treat primates with symptoms of the debilitating disease.

So-called iPS cells are made by removing mature cells from an individualoften from the skinand reprogramming them to behave like embryonic stem cells. They can then be coaxed into dopamine-producing brain cells.

The scientists from Kyoto University, a world-leader in iPS technology, said their experiment indicated that this approach could potentially be used for the clinical treatment of human patients with Parkinsons.

In addition to boosting dopamine production, the tests showed improved movement in affected monkeys and no tumors in their brains for at least two years.

The human iPS cells used in the experiment worked whether they came from healthy individuals or Parkinsons disease patients, the Japanese team reported in the journal Nature on Wednesday.

This is extremely promising research demonstrating that a safe and highly effective cell therapy for Parkinsons can be produced in the lab, said Tilo Kunath of the MRC Centre for Regenerative Medicine, University of Edinburgh, who was not involved in the research.

The next step will be to test the treatment in a first-in-human clinical trial, which Jun Takahashi of Kyoto University told Reuters he hoped to start by the end of 2018.

Any widespread use of the new therapy is still many years away, but the research has significantly reduced previous uncertainties about iPS-derived cell grafts.

The fact that this research uses iPS cells rather human embryonic stem cells means the treatment would be acceptable in countries such as Ireland and much of Latin America, where embryonic cells are banned.

Excitement about the promise of stem cells has led to hundreds of medical centers springing up around the world claiming to be able to repair damaged tissue in conditions such as multiple sclerosis and Parkinsons.

While some treatments for cancer and skin grafts have been approved by regulators, many other potential therapies are only in early-stage development, prompting a warning last month by health experts about the dangers of stem-cell tourism.

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Human Stem Cells Fight Parkinson's Disease in Monkeys - Scientific American

Skin Stem Cells Comments Off on Human Stem Cells Fight Parkinson’s Disease in Monkeys – Scientific American | September 1st, 2017

Microneedling has quickly become one of the most popular skin rejuvenation treatments. If youre considering trying it, here is what you need to know.

Microneedling, also called collagen-induction therapy, uses small needles that pierce the outermost layer of skin to create tiny microchannels. These microchannels help stimulate the production of collagen and elastin within the skin. They also promote new capillaries.

This can lead to an improved skin texture, reduction of acne or other scarring and help with discoloration, such as brown spots caused by sun damage. Microneedling may be combined with platelet-rich plasma, stem cells, or pure hyaluronic acid to enhance results further.

Microneedling can also be used on the scalp to help stimulate hair rejuvenation.

Prior to your first microneedling session, you will be asked to avoid sun exposure for at least 24 hours. Some doctors will tell you to avoid blood-thinning medications and herbal supplements like aspirin, ibuprofen, and St. Johns wort to reduce bruising.

Each microneedling session takes about 20 to 30 minutes. First, your face will be cleansed and a numbing cream will be applied. Multiple treatment sessions, spaced a few weeks apart, are recommended. Most doctors recommend three to six treatments but many will notice an improvement in the tone and texture of their skin after just one treatment.

Immediately after your microneedling session, you will likely notice some redness that can last for several days. In my practice, we recommend that patients do not touch their face for at least four hours after treatment and not to apply anything to the face for 24 hours. It is crucial to avoid sun exposure for three days after the procedure.

You should avoid strenuous activity and exercise for the first 12 hours after treatment to prevent redness and bruising. For the first three days after treatment, you should use a gentle non-foaming cleanser, a barrier repair moisturizer, and a physical SPF. If swelling or bruising are a concern, you can take arnica supplements both before and after treatment to help minimize these side effects.

Once any redness or swelling diminishes, you should notice an immediate improvement in the way your skin looks and feels. Over the next several weeks, your skins appearance should continue to improve.

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Here's What You Need to Know about Microneedling - Miami Herald

Skin Stem Cells Comments Off on Here’s What You Need to Know about Microneedling – Miami Herald | September 1st, 2017

| Marlowe Hood |

PARIS (AFP) Lab monkeys with Parkinsons symptoms regained significant mobility after neurons made from human stem cells were inserted into their brains, researchers reported Wednesday in a study hailed as groundbreaking.

The promising results were presented as the last step before human clinical trials, perhaps as early as next year, the studys senior author, Jun Takahashi, a professor at Kyoto University, told AFP.

Parkinsons is a degenerative disease that erodes motor functions. Typical symptoms include shaking, rigidity and difficulty walking. In advanced stages, depression, anxiety and dementia are also common.

Worldwide, about 10 million people are afflicted with the disease, according to the Parkinsons Disease Foundation.

Earlier experiments had shown improvements in patients treated with stem cells taken from human foetal tissue and likewise coaxed into the dopamine-producing brain cells that are attacked by Parkinsons.

Dopamine is a naturally occurring chemical that plays several key roles in the brain and body.

But the use of foetal tissue is fraught with practical and ethical problems.

So Takahashi and his colleagues, in a medical first, substituted so-called induced pluripotent stem cells (iPSCs), which can be easily made from human skin or blood. Within a year, some monkeys who had could barely stand up gradually recovered mobility.

They became more active, moving more rapidly and more smoothly, Takahashi said by email. Animals that had taken to just sitting start walking around in the cage.

These findings are strong evidence that human iPSC-derived dopaminergic neurons can be clinically applicable to treat Parkinsons patients, he said.

Experts not involved in the research described the results as encouraging.

The treatment, if proven viable, has the potential to reverse Parkinsons by replacing the dopamine cells that have been lost a groundbreaking feat, said David Dexter, deputy research director at Parkinsons UK.

Not only did the new cells survive but they also integrated with the existing neuronal network, he said.

Neurons made from foetal tissue grafted into brains have been known to survive for more than a decade, and the researchers said they expected those derived from iPSCs to last just as long.

Tilo Kunath, Parkinsons Senior Research Fellow at the University of Edinburgh, said the outcome was extremely promising, and highlighted the advantage of avoiding stem cells extracted from human foetal tissue.

It means that this therapy can be used in any country worldwide, including Ireland and most of South America, where medical use of human embryonic stem cells is banned.

The results, reported in the journal Nature, were not the same for the dozen monkeys in the experiment, each of which received donor neurons from a different person.

Some were made with cells from healthy donors, while others were made from Parkinsons disease patients, said lead author Tetsuhiro Kikuchi, also from Kyoto University.

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Study shows human stem cells restore mobility in Parkinson's monkeys - Borneo Bulletin Online

Skin Stem Cells Comments Off on Study shows human stem cells restore mobility in Parkinson’s monkeys – Borneo Bulletin Online | September 1st, 2017

Tippi MacKenzie, MD, a pediatric and fetal surgeon at UCSF Benioff Childrens Hospital San Francisco, is the principal investigator for a clinical trial that will use in utero stem cell transplants to treat fetuses with an inherited disorder that restricts the bloods ability to carry oxygen to vital organs. Credit: Cindy Chew

UCSF Benioff Children's Hospitals in San Francisco and Oakland will pioneer stem cell transplants for a uniquely challenging patient population: second-trimester fetuses stricken with a potentially fatal disease.

The two hospitals are enrolling 10 pregnant women in the first phase of a clinical trial to treat fetuses with an inherited disorder that restricts the blood's ability to carry oxygen to vital organs. The trial, the first of its kind in the world, is funded by a $12.1 million grant from the California Institute for Regenerative Medicine.

Alpha thalassemia (ATM) affects 5 percent of the world's population, but is significantly more prevalent in China, Southeast Asia, India and the Middle East parts of the globe where many residents of the San Francisco Bay Area claim their origins. In its most extreme form, alpha thalassemia major (ATM), the condition leads to progressive anemia and heart failure before birth. Standard treatment in the United States includes lifelong blood transfusions.

Stem cell transplants from a matched donor in childhood have proven to be curative in some cases, but patients face risks, including graft-versus-host disease and serious side effects from immune-suppression drugs.

The trial is based on the premise that risks could be minimized by harnessing the "tolerance" between the pregnant woman and fetus before birth, said principal investigator Tippi MacKenzie, MD, a pediatric and fetal surgeon at UCSF Benioff Children's Hospital San Francisco.

Hope That Procedure Could Be Adopted Worldwide

"In performing the procedure in utero when the fetus's immune system is underdeveloped, we can avoid the aggressive treatments required for postnatal transplants for children with alpha thalassemia," MacKenzie said. "Eventually, the procedure may become a treatment option in parts of the world where ATM is most common. Due to lack of treatment possibilities in many countries, most pregnancies are either terminated on diagnosis or result in fetal demise," she said.

The trial follows a decades-long odyssey marked by triumphs and tribulations for researchers in the field. Fetal transplants using stem cells from other fetuses to treat blood disorders were carried out in the 1980s, but were only marginally successful due to engraftment failure. Researchers around the world searched for answers by turning to animal studies.

'Eureka Moment' Spurred Sea Change

"The fetus, unlike a fully developed human, can accept foreign cells, because its immune system is not yet primed to fight bacteria and viruses," said MacKenzie. "This undeveloped immune system benefits the fetus throughout the pregnancy, because it prevents it from launching an immune response to its mother's cells that are naturally circulating in its bloodstream."

Further research led to Mackenzie's "eureka moment," when it was discovered that the mother's immune system is actually responsible for rejecting other cells that are transplanted into the fetus. If the mother's cells are transplanted, they can engraft without being rejected. "This led to a sea change in our strategy to use maternal cells for the transplants," she said.

In the trial, bone marrow will be collected from women who are between 18 and 25 weeks pregnant, with a fetal diagnosis of ATM. The bone marrow cells will be processed and hematopoietic cells immature stem cells that can evolve into all types of blood cells will be singled out from the mix. They will then be injected through the woman's abdomen, into the umbilical vein of the fetus, where they can circulate through the bloodstream, developing into healthy mature blood cells.

The procedure is not without risks to the fetus and the pregnant woman. To minimize risks, the researchers restricted the trial to ATM, since the fetus is already undergoing blood transfusions. "An additional procedure for the transplantation is not necessary, since the maternal stem cells are infused at the same time as an in utero blood transfusion," said Elliott Vichinsky, MD, director of hematology/oncology at UCSF Benioff Children's Hospital Oakland, who will head the hematologic management of the fetus and newborn. "This should reduce additional risks to the fetus." Since the underlying disease causes complications, the woman will be monitored throughout her pregnancy and the fetus will continue to receive blood transfusions until birth.

UCSF is a pioneer in thalassemia research and the birthplace of fetal surgery. UCSF Benioff Children's Hospital Oakland is home to the Northern California Comprehensive Thalassemia Center, which was established in 1991 and is now the largest such program nationwide, with a focus on caring for patients and leading research into new treatments.

"We are excited about launching this trial, which combines the expertise of UCSF Benioff Children's Hospitals in San Francisco and Oakland. This study offers families with a usually fatal ATM pregnancy the chance of survival and cure," said Vichinsky, who founded the Northern California Comprehensive Thalassemia Center.

Treatment May Be Tested for Sickle Cell Anemia

Patient recruitment will continue for five years, during which pregnant women and their babies will be followed after birth for 30 days and one year respectively. If successful, the procedure will be carried out for fetuses with beta thalassemia, a more common and less serious variant of the disorder, as well as sickle cell anemia, in collaboration with Children's Hospital of Philadelphia. Other conditions requiring stem cell transplants after birth may be considered, said MacKenzie.

The incidence of ATM is unknown because most fetuses with the disorder die before delivery. The condition occurs when both parents are carriers for thalassemia. In places where women have access to prenatal care, ATM is usually suspected on ultrasound and confirmed by DNA analysis in the second trimester.

Explore further: Immune system drives pregnancy complications after fetal surgery in mice

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In utero stem cell transplants may replace riskier childhood transplants for multiple conditions - Medical Xpress

Bone Marrow Stem Cells Comments Off on In utero stem cell transplants may replace riskier childhood transplants for multiple conditions – Medical Xpress | August 31st, 2017

From left to right: Richard Stone, a doctor at Dana-Farber Cancer Institute in Boston, poses with Peter Karalekas (center), 76, and Matthew Churitch, 22. Churitch donated stem cells to Karalekas two years ago, and he visited Dana-Farber with Karalekas earlier this summer. (Courtesy photo)

BOSTON -- After winding his way through Massachusetts, Connecticut, New Hampshire and Maine for 76 years, Peter Karalekas has a proclamation: He's a Southerner now.

He still lives in Kittery, Maine, just about an hour from the Lowell middle school where he taught for 21 years.

He has no plans to move.

Rather, Karalekas considers himself a Southerner because of his stem cells.

He never exactly felt all that sick.

Karalekas worked tirelessly for decades, first as a teacher and coach at the James S. Daley Middle School in Lowell and then as the owner of a half-dozen T-Bones restaurants across New Hampshire.

Even despite the 12-hour days, seven days a week, in the grind of the restaurant industry, Karalekas felt healthy and rarely fell ill.

Peter Karalekas, left, a 76-year-old former Lowellian, smiles during his first meeting with Matthew Churitch, 22, of Nashville, Tennessee, who helped save Karalekas life by donating stem cells. (Courtesy photo)

The two, who do not have children, moved to Kittery 17 years ago.

Everything started to change in 2014.

Karalekas recalls being "short-winded," but he had very few other symptoms when he was diagnosed with myelodysplastic syndrome, a rare type of cancer in which the bone marrow is damaged and cannot produce enough blood cells.

The prognosis was not good.

"They said the only thing that would save me was a stem cell transplant," Karalekas said. "Otherwise, I had a couple of months to live, because my cells were all dropping drastically.

He went onto a registry, hoping for a donor to pop up, but doctors told him it could take from six months to two years to find the right match. Even with a transplant, Karalekas said, his chances of success were "30 to 40 percent."

The call came four weeks later.

Matthew Churitch got his call quickly, too.

He joined the National Marrow Donor Program's Be the Match Registry in 2014, the summer between his freshman and sophomore years at Clemson University. His mother had been on the registry to donate for years. Churitch's decision was simple: When a friend was diagnosed with leukemia, he knew he should sign up, too.

He did the requisite cheek swab, unsure if he would ever even be contacted to donate. By the time he had finished the following semester, he got the call.

A match was found.

Churitch went through several more levels of testing and preparation to donate stem cells to a stranger. He went to Clemson's student health center to have blood drawn.

He returned to his native Nashville, Tennessee, going to a medical center 10 days in a row to receive shots in his stomach that would stimulate his bone marrow and prepare his cells for transplant.

He sat for eight hours, a needle in each arm as his stem cells were filtered out so they could be transferred to Boston.

"Getting the shots isn't fun," he said. "You're pretty sore afterward for a few weeks. But knowing that the person on the other end is in hundreds and hundreds times more pain than any donor would ever go through -- that kind of pushed me through."

Karalekas and Churitch first connected via an anonymous letter, per the transplant registry's rules, updating Churitch on Karalekas's lengthy, isolated recovery. They were able to speak directly after a year.

Churitch dialed Karalekas' number on a lengthy walk to class, took a deep breath and hit the call button. Moments later, both men were crying and laughing.

"That was really awesome, just being able to hear his voice and recognize that there's somebody else on the other end of this," Churitch said. "A lot of people don't get the chance to connect with their recipients or their donors."

Karalekas wanted more. He told his wife early on that he wanted to meet his "angel from heaven," so when Churitch graduated Clemson earlier this year, Karalekas paid to bring the 22-year-old and his mother to New England.

In late June, Karalekas and his wife pulled into a pickup lane at Logan International Airport in Boston.

"I got out of the car, I charged over, and I gave them both a huge hug," Karalekas said.

Karalekas showed Churitch and his mother around for five days.They went on a private tour of Fenway Park; they wandered the historic streets of Portsmouth, New Hampshire; they visited Dana-Farber together to meet the team that treated Karalekas.

Both families quickly bonded. Karalekas recalls his brother George asking Churitch about his portable phone charger, expressing curiosity about how convenient it was. A few weeks later, a brand-new portable charger arrived at George's door, a gift from Churitch.

In January, Karalekas and his wife will vacation in Arizona and will cheer on Churitch's mother -- without Churitch even present -- in the Phoenix Marathon.

Donor and recipient talk every week.

"It's like we're a very, very close-knit family now," Karalekas said. "He's the son we never had."

Churitch is now in his first year at the University of South Carolina School of Medicine Greenville with hopes of becoming a physician. He hopes to use Karalekas's experience as inspiration for any patients facing future hardship, and he hopes that others, especially young people, will see their success and join the registry.

"You never know where that will take you," he said. "You can gain a friend for life, impact somebody and their family in need."

Karalekas said he feels he has a new life: His chances of beating the disease are now 97 percent, he says, up from the 30 percent or 40 percent when he started treatment. Thanks to the transplant from a handsome, athletic college student in Tennessee.

"I said, 'I'm a Southerner now,'" Karalekas said. "My stem cells are 99 percent this gentleman. I'm 99 percent him."

Follow Chris on Twitter @ChrisLisinski.

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For Lowell native, stem cell match becomes a match as friends - Lowell Sun

Bone Marrow Stem Cells Comments Off on For Lowell native, stem cell match becomes a match as friends – Lowell Sun | August 31st, 2017

AsianScientist (Aug. 30, 2017) - In a study published in Cell Stem Cell, scientists in Japan and Switzerland have found that bacterial infections can stress blood-producing stem cells in the bone marrow and reduce their ability to self-replicate.

When a person becomes infected with a virus or bacteria, immune cells in the blood or lymph react to the infection. Some of these immune cells use sensors on their surfaces, called Toll-like receptors (TLR), to distinguish invading pathogens from molecules that are expressed by the host. By doing so, they can attack and ultimately destroy pathogens thereby protecting the body without attacking host cells.

Bone marrow contains hematopoietic stem cells which create blood cells, such as lymphocytes and erythrocytes, throughout the lifetime of an individual. When infection occurs, a large number of immune cells are activated and consumed. Hence, it is necessary to replenish these immune cells by increasing blood production in bone marrow.

Recent studies have revealed that immune cells are not the only cells that detect the danger signals associated with infection. Hematopoietic stem cells also identify these signals and use them to adjust blood production. However, little was known about how hematopoietic stem cells respond to bacterial infection or how it affected their function.

In this study, researchers from Kumamoto University and the University of Zurich analyzed the role of TLRs in hematopoietic stem cells upon bacterial infection, given that both immune cells and hematopoietic stem cells have TLRs.

To generate a model of bacterial infection, researchers injected one of the key molecules found in the outer membrane of gram negative bacteria and known to cause sepsislipopolysaccharide (LPS)into lab mice. They then analyzed the detailed role of TLRs in hematopoietic stem cell regulation by combining genetically modified animals that do not have TLR and related molecules, or agents that inhibit these molecules.

The results showed that LPS spread throughout the body, with some eventually reaching the bone marrow. This stimulated the TLRs of the hematopoietic stem cells and induced them to proliferate. They also discovered that while LPS promoted stem cell proliferation, it also induced stressed the stem cells, impairing their ability to successfully self-replicate and resulting in diminished blood production. Similar results were obtained after infection with Escherichia coli bacteria.

Fortunately we were able to confirm that this molecular reaction can be inhibited by drugs, said Professor Hitoshi Takizawa of Kumamoto University who led the study. The medication maintains the production of blood and immune cells without weakening the immune reaction against pathogenic bacteria. It might be possible to simultaneously prevent blood diseases and many bacterial infections in the future.

The article can be found at: Takizawa et al. (2017) Pathogen-Induced TLR4-TRIF Innate Immune Signaling in Hematopoietic Stem Cells Promotes Proliferation but Reduces Competitive Fitness.

Source: Kumamoto University.Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.

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Bacterial Infection Stresses Blood Stem Cells - Asian Scientist Magazine

Bone Marrow Stem Cells Comments Off on Bacterial Infection Stresses Blood Stem Cells – Asian Scientist Magazine | August 31st, 2017

A team of scientists found a way to create a novel drug delivery system for an array of different conditions.

Researchers at the Fred Hutchinson Cancer Research Center developed a biomedical tool that harnesses nanoparticles to deliver transient gene changes to specified cells.

This system extends the therapeutic potential of messenger RNA (mRNA). This biological element is responsible for delivering molecular instructions from DNA to other cells in the body making them produce proteins to prevent or attack a disease.

The technique involves mixing freeze-dried nanoparticles with water and a sample of cells.

"Our goal is to streamline the manufacture of cell-based therapies," said lead author and biomaterials expert Dr. Matthias Stephan, a faculty member in the Fred Hutch Clinical Research Division, in a statement. "In this study, we created a product where you just add it to cultured cells and that's it -- no additional manufacturing steps."

Heres how this technology worked in three experiments targeting T-cells in the immune system and blood stem cells in a process they called hit-and-run genetic programming.

The team imbued these nanoparticles with a gene editing tool and sent them to T-cells residing in the immune system to snip out their natural T-cell receptors. They were then paired with genes encoding a CAR, otherwise known as a chimeric antigen receptor, designed to attack cancer.

Next, the researchers engineered the nanoparticles to target blood stem cells. They were equipped with mRNA that enabled the stem cells to multiply and replace blood cancer cells with healthy cells when used in bone marrow transplants.

Finally, the nanoparticles were targeted to CAR-T cells containing foxo1 mRNA that signaled to the anti-cancer T-cells to develop into a form of memory cell that exhibits more aggressive behavior and destroys tumor cells more effectively.

Other attempts to engineer the mRNA into disease-fighting cells were more difficult. The large messenger molecules degraded quickly before it could make it have an effect while the bodys immune system recognized it as foreign.

Still, this process could replace the more labor-intensive alternative called electroporation, a multistep cell-manufacturing technique that requires specialized equipment and clean rooms.

Stephan is currently looking for commercial partners to help move into clinical trials.

The study was published in the journal Nature Communications.

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Nanoparticle Advance Could Yield Multi-Purpose Treatments - Drug Discovery & Development

Bone Marrow Stem Cells Comments Off on Nanoparticle Advance Could Yield Multi-Purpose Treatments – Drug Discovery & Development | August 31st, 2017

Parkinsons stem cell breakthrough

Miodrag Stojkovic/Science Photo Library

By Helen Thomson

MONKEYS with a Parkinsons-like disease have been successfully treated with stem cells that improved their movement for up to two years after transplant. A similar trial is now being prepared for people.

Parkinsons destroys dopamine-producing cells in the brain, leading to tremors and difficulty moving. Previous experiments using stem cells from embryos have shown promise in replacing lost cells, but the use of these is controversial.

Jun Takahashi at Kyoto University, Japan, and colleagues wondered whether they could treat monkeys with a disease like Parkinsons using induced pluripotent stem cells, which are made by coaxing blood or skin cells into becoming stem cells.

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The team generated stem cells from three people with Parkinsons and four without the disease. They then transformed these into dopamine-producing brain cells.

All the monkeys who received injections of these cells showed a 40 to 55 per cent improvement in their movements, matching results from previous experiments with embryonic stem cells. Monkeys who had a control injection minus the cells didnt improve (Nature, DOI: 10.1038/nature23664).

Stem cells from people with and without Parkinsons were equally effective. The monkeys became more active and showed less tremor, says Takahashi. Their movements became smoother.

After the transplant, the monkeys were given immunosuppressive drugs to prevent the new cells from being rejected and observed for up to two years. No serious side effects appeared during this time.

This study shows that the stem cells behave as you would like them to and they appear safe, says Roger Barker of the University of Cambridge. All of which gives one greater confidence in moving to human studies.

This article appeared in print under the headline Parkinsons stem cell breakthrough

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Human blood and skin cells used to treat Parkinson's in monkeys - New Scientist

Skin Stem Cells Comments Off on Human blood and skin cells used to treat Parkinson’s in monkeys – New Scientist | August 31st, 2017

Spinal injuries are oftenpermanent, but new research suggests such injuries may be healed, at least in part.Researchers were able to stimulate limb function in paralyzed mice by implanting human stem cells into theirspinal cords. We're not close to repeating the test in people, but the study shows it may be possible some day with further research.

The University of California-San Diego team grafted human neural stem cells (NSCs) into the spinal cord injuries of mice who were purposely injuredto impair the use of their front legs. The stem cells grew slowly, yet steadily, over the course of 18 months, retaining their original function despite being in a strange and challenging environment for an extended period of time. Whats more, eventually the rodents were able to use their front legs again.

"The bottom line is that clinical outcome measures for future trials need to be focused on long time points after grafting," said study researcher Mark Tuszynskiin a recent statement. Relying on shorter time frames might produce misleadingly negative results considering how long it takes neural stem cells to develop, he added.

For the study, the team used H9 human NSCs, which are a type of stem cell derived from human embryonic stem cells, as commonly used in scientific research, the statement reported. They then grafted these human stem cells into the spinal injuries of mice. The researchers observed the rodents recovery over the course of 18 months, noting that significant cellgrowth did occur soon after grafting, and continued up to a year after the initial implantation.

The most important observation was that these cells were able to continue to do what they were designed to doregrow neural cellsdespite the fact that they were transplanted into an entirely different species. This suggests the cells have resilience and similar experiments mayalso work in human subjects.

Before you get too excited about these results, the researchers emphasized that there were a number of caveats. First, humans and mice are entirely different species, and though the results observed in the rodents are promising, we don't know if they could be repeated in people.

Also, the researchers observed that some astrocytes, star-shaped neural cells associated with electrical impulse transmission, did migrate from the original implantation site to other areas of the rodents. These brain cells are classified as glial cells, which are noted to lead to devastating and difficult to treat cancers when they are dysregulated, Harvard University reported. However, there were no tumors or abnormal growths observed in the mice in the study and the researchers are trying to figure out way to make sure cancer doesn't develop.

Ultimately, the team believe that these results stand as a good foundation on which to buildfurther research.

Success, it would seem, will take time," concluded Tuszynski.

Source: Lu P, Ceto S, Wang Y, et al. Prolonged human neural stem cell maturation supports recovery in injured rodent CNS. The Journal of Clinical Investigation . 2017

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Stem Cell Graft Repairs Spinal Cord Injury, Helps Paralyzed Mice ... - Medical Daily

Spinal Cord Stem Cells Comments Off on Stem Cell Graft Repairs Spinal Cord Injury, Helps Paralyzed Mice … – Medical Daily | August 31st, 2017

A brain cell replacement therapy reduced Parkinsons disease symptoms in monkeys, Japanese researchers report in a study released Wednesday. The positive result boosts prospects to test the therapy in people.

The goal is to implant neurons derived from stem cells into the brains of Parkinsons patients, a project pursued by scientists in San Diego, New York, Britain and Sweden as well as in Japan. If all goes well, the neurons will function as replacements for those destroyed in the disease.

In addition, human testing of a related brain cell therapy from Carlsbads International Stem Cell Corp. is already under way in Australia.

While treatments exist for the movement disorders caused by Parkinsons, none of them actually halt progression. Replacing the brain cells destroyed in Parkinsons holds the promise of actually reversing the disease.

Moreover, success with Parkinsons could pave the way to treating many other neurodegenerative diseases, such as ALS (Lou Gehrigs disease) and perhaps Alzheimers, along with brain and spinal cord injuries. These afflictions cost hundreds of billions annually, and most importantly, produce immense suffering in patients and caregivers.

Years of extensive research are required before any such therapy can be tried in people. Testing in monkeys or other primates is often regarded as the last step before human treatment can be contemplated.

The study was published in the journal Nature. Its senior author was Jun Takahashi, a prominent stem cell researcher at Kyoto University in Kyoto, Japan. Go online to j.mp/parkips for the study.

There is precedent to suggest the therapy might work. Beginning decades ago, brain cells taken from human fetuses have been implanted into the brains of Parkinsons patients, with mixed results. Some patients experienced improved movement control. But others gained nothing, or experienced uncontrolled movements.

Scientists in the field say using stem cells should provide improved results. Stem cells can be made in greater quantity than the limited number of fetal brain cells available. In addition, the stem cells and neurons made from them can be analyzed for quality before implantation.

The study was praised by regenerative medicine researcher Tilo Kunath at the University of Edinburgh, in comments provided by the UK Science Media Centre.

This is extremely promising research demonstrating that a safe and highly effective cell therapy for Parkinsons can be produced in the lab, Kunath said.

Such a therapy has the potential to reverse the symptoms of Parkinsons in patients by restoring their dopamine-producing neurons. The next stage will be to test these therapies in a first-in-human clinical trial.

In the study, researchers produced neurons that secrete dopamine, a neurotransmitter deficient in Parkinsons disease. These neurons were made from human stem cells derived from both healthy people and those with Parkinsons.

The researchers then implanted the human neurons into 10 monkeys whose own dopamine-making neurons had been destroyed. The monkeys were given immunosuppressive drugs to prevent rejection of the human cells.

The human neurons integrated into the brains of the monkeys and functioned as dopamine-making neurons. The monkeys improved in movement ability, save for one monkey that became ill and was euthanized. Both cells from healthy and Parkinsons patients were effective.

A companion study in Nature Communications demonstrated a method of immune-matching the cells to reduce the immune response. Takahashi was also senior author of that study. Go online to j.mp/ipsimmune for the study.

Both studies used artificial embryonic stem cells, called induced pluripotent stem cells (IPS). These act-alike cells are not derived from embryos, but are genetically reprogrammed from adult cells, usually skin cells.

The IPS cells appear to act virtually identically to embryonic stem cells, but dont raise the ethical objections many have to using embryonic stem cells. These cells were invented in 2006 by a team led by Shinya Yamanaka, a co-author of the Nature Communications study.

Moreover, the cells can be made from the patients themselves, which is not expected to cause an immune reaction. This is the approach taken by the San Diego team, including scientists at The Scripps Research Institute.

Carlsbads International Stem Cell Corp. uses a different approach. It starts with unfertilized, or parthenogenetic, human egg cells. These are grown into immature neurons that are implanted. The cells are expected to grow not only into dopamine-making neurons, but other kind of brain cells that preserve the remaining neurons.

The Australian clinical trial has gathered evidence of safety, and continued testing is under way determine efficacy.

The Nature study dovetails with research by the San Diego group, Summit for Stem Cell, (www.summitforstemcell.org), including scientists at The Scripps Research Institute and doctors at Scripps Health.

The group proposes to treat Parkinsons patients with neurons grown from their own IPS cells. The scientists have received funding from the California Institute for Regenerative Medicine, the states stem cell agency.

The studies support the personalized approach that we are taking for a neuron replacement therapy for Parkinson's disease patients, said Jeanne Loring and Andres Bratt-Leal, stem cell scientists at The Scripps Research Institute.

Two points from the studies should be highlighted, Loring and Bratt-Leal said by email.

Parkinson's disease is a late-onset disorder, they said. That means that there was nothing wrong with the neurons that people with Parkinson's were born with. Few PD patients have a family history of the disease, which suggests that genetic mutations did not cause their disease.

So for the great majority of patients, transplantation of their own neurons is a promising approach to relieving symptoms, without having to take expensive and risky immunosuppressive drugs, they said.

The Summit for Stem Cell scientists are members of an international partnership of laboratories developing neuron replacement therapies for Parkinsons, called GForce PD.

Takahashi belongs to the partnership, as do scientists in the UK, Sweden and New York. These use both embryonic and IPS stem cells. The Summit for Stem Cell effort is the only one using patient-matched IPS cells, Loring and Bratt-Leal said.

Brain cells reprogrammed to make dopamine, with goal of Parkinsons therapy

Parkinson's stem cell therapy shows signs of safety

Parkinson's therapy funded by California's stem cell agency

Dopamine-making neurons can be chemically controlled in animal model of Parkinson's

Stem cell clinical trial for Parkinson's begins

Summit for Stem Cell

bradley.fikes@sduniontribune.com

(619) 293-1020

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Brain cell replacement for Parkinson's boosted by monkey study - The San Diego Union-Tribune

Spinal Cord Stem Cells Comments Off on Brain cell replacement for Parkinson’s boosted by monkey study – The San Diego Union-Tribune | August 31st, 2017

B. Bick, . Poindexter, UT Med. School/SPL

A depletion of brain cells that produce dopamine is responsible for the mobility problems seen in people with Parkinsons disease.

Japanese researchers report promising results from an experimental therapy for Parkinsons disease that involves implanting neurons made from reprogrammed stem cells into the brain. A trial conducted in monkeys with a version of the disease showed that the treatment improved their symptoms and seemed to be safe, according to a report published on 30 August in Nature1.

The studys key finding that the implanted cells survived in the brain for at least two years without causing any dangerous effects in the body provides a major boost to researchers hopes of testing stem-cell treatments for Parkinsons in humans, say scientists.

Jun Takahashi, a stem-cell scientist at Kyoto University in Japan who led the study, says that his team plans to begin transplanting neurons made from induced pluripotent stem (iPS) cells into people with Parkinsons in clinical trials soon.

The research is also likely to inform several other groups worldwide that are testing different approaches to treating Parkinsons using stem cells, with trials also slated to begin soon.

Nature breaks down the latest research and what it means for the future of stem-cell treatments.

Parkinsons is a neurodegenerative condition caused by the death of cells called dopaminergic neurons, which make a neurotransmitter called dopamine in certain areas of the brain. Because dopamine-producing brain cells are involved in movement, people with the condition experience characteristic tremors and stiff muscles. Current treatments address symptoms of the disease but not the underlying cause.

Researchers have pursued the idea that pluripotent stem cells, which can form any cell type in the body, could replace dead dopamine-making neurons in people with Parkinsons, and thus potentially halt or even reverse disease progression. Embryonic stem cells, derived from human embryos, have this capacity, but they have been the subject of ethical debates. Induced pluripotent stem (iPS) cells, which are made by coaxing adult cells into an emybronic-like state, have the same versatility without the associated ethical concerns.

Takahashis team transformed iPS cells derived from both healthy people and those with Parkinsons into dopamine-producing neurons. They then transplanted these cells into macaque monkeys with a form of the disease induced by a neuron-killing toxin.

The transplanted brain cells survived for at least two years and formed connections with the monkeys brain cells, potentially explaining why the monkeys treated with cells began moving around their cages more frequently.

Crucially, Takahashis team found no sign that the transplanted cells had developed into tumours a key concern with treatments that involve pluripotent cells or that they evoked an immune response that couldnt be controlled with immune-suppressing drugs.

Its addressing a set of critical issues that need to be investigated before one can, with confidence, move to using the cells in humans, says Anders Bjorklund, a neuroscientist at Lund University in Sweden.

I hope we can begin a clinical trial by the end of next year, says Takahashi. Such a trial would be the first iPS cell trial for Parkinson's. In 2014, a Japanese woman in her 70s became the first person to receive cells derived from iPS cells, to treat her macular degeneration.

In theory, iPS cells could be tailor-made for individual patients, which would eliminate the need to use drugs that suppress a possible immune response to foreign tissues.

But customized iPS cells are expensive to make and can take a couple months to derive and grow, Takahashi notes. So his team instead plans to establish iPS cell lines from healthy people and then use immune cell biomarkers to match them to people with Parkinsons in the hope of minimizing the immune response (and therefore the need for drugs to blunt the attack).

In a study described in an accompanying paper in Nature Communications2, Takahashis team implanted into monkeys iPS-cell-derived neurons from different macaques. They found that transplants between monkeys carrying similar white blood cell markers triggered a muted immune reaction.

Earlier this year, Chinese researchers began a Parkinsons trial that used a different approach: giving patients neural-precursor cells made from embryonic stem cells, which are intended to develop into mature dopamine-producing neurons. A year earlier, in a separate trial, patients in Australia received similar cells. But some researchers have expressed concerns that the immature transplanted cells could develop tumour-causing mutations.

Meanwhile, researchers who are part of a Parkinsons stem-cell therapy consortium called GForce-PD, of which Takahashis team is a member, are set to bring still other approaches to the clinic. Teams in the United States, Sweden and the United Kingdom are all planning trials to transplant dopamine-producing neurons made from embryonic stem cells into humans. Previously established lines of embryonic stem cells have the benefit that they are well studied and can be grown in large quantities, and so all trial participants can receive a standardized treatment, notes Bjorklund, also a consortium member.

Jeanne Loring, a stem-cell scientist at the Scripps Research Institute in La Jolla, California, favours transplanting iPS-derived neurons made from a patients own cells. Although expensive, this approach avoids dangerous immunosuppressive drugs, she says. And because iPS cells are established anew for each patient, the lines go through relatively few cell divisions, minimizing the risk that they will develop tumour-causing mutations. Loring hopes to begin her teams trial in 2019. This shouldnt be a race and were cheering for success by all, she says.

Lorenz Studer, a stem-cell scientist at the Memorial Sloan Kettering Cancer Center in New York City who is working on a trial that will use neurons made from embryonic stem cells, says that there are still issues to work out, such as the number of cells needed in each transplant procedure. But he says that the latest study is a sign that we are ready to move forward.

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Reprogrammed cells relieve Parkinson's symptoms in trials - Nature.com

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Biol Res 45: 279-287, 2012

RESEARCH ARTICLES

In Osteoporosis, differentiation of mesenchymal stem cells (MSCs) improves bone marrow adipogenesis

Ana Mara Pino1, Clifford J. Rosen2 and J. Pablo Rodrguez1*

1Laboratorio de Biologa Celular y Molecular, INTA, Universidad de Chile, 2Maine Medical Center Research Institute, Scarborough, Maine, USA.

ABSTRACT

The formation, maintenance, and repair of bone tissue involve close interlinks between two stem cell types housed in the bone marrow: the hematologic stem cell originating osteoclasts and mesenchymal stromal cells (MSCs) generating osteoblasts. In this review, we consider malfunctioning of MSCs as essential for osteoporosis. In osteoporosis, increased bone fragility and susceptibility to fractures result from increased osteoclastogenesis and insufficient osteoblastogenesis.

MSCs are the common precursors for both osteoblasts and adipocytes, among other cell types. MSCs' commitment towards either the osteoblast or adipocyte lineages depends on suitable regulatory factors activating lineage-specific transcriptional regulators. In osteoporosis, the reciprocal balance between the two differentiation pathways is altered, facilitating adipose accretion in bone marrow at the expense of osteoblast formation; suggesting that under this condition MSCs activity and their microenvironment may be disturbed. We summarize research on the properties of MSCs isolated from the bone marrow of control and osteoporotic post-menopausal women. Our observations indicate that intrinsic properties of MSCs are disturbed in osteoporosis. Moreover, we found that the regulatory conditions in the bone marrow fluid of control and osteoporotic patients are significantly different. These conclusions should be relevant for the use of MSCs in therapeutic applications.

Key words: MSCs, osteoporosis, adipogenesis, bone marrow microenvironment

BACKGROUND

The formation, maintenance, and repair of bone tissue depend on fine-tuned interlinks in the activities of cells derived from two stem cell types housed in the bone marrow interstice. A hematologic stem cell originates osteoclasts, whereas osteoblasts derive from mesenchymal stem cells (MSCs). Bone tissue is engaged in an unceasing process of remodelling through the turnover and replacement of the matrix: while osteoblasts deposit new bone matrix, osteoclasts degrade the old one.

Bone marrow provides an environment for maintaining bone homeostasis. The functional relationship among the different cells found in bone marrow generates a distinctive microenvironment via locally produced soluble factors, the extracellular matrix components, and systemic factors (Raisz, 2005; Sambrook and Cooper, 2006), allowing for autocrine, paracrine and endocrine activities. If only the main cellular components of the marrow stroma are considered, the activity of adipocytes, macrophages, fibroblasts, hematopoietic, endothelial and mesenchymal stem cells and their progeny bring about a complex range of signals.

Osteoporosis is a bone disease characterized by both decreased bone quality and mineral density. In postmenopausal osteoporosis, increased bone fragility and susceptibility to fractures result from increased osteoclastogenesis, inadequate osteoblastogenesis and altered bone microarchitecture.

The pathogenesis of the disease is hitherto unknown, hence the interest in basic and clinical research on the mechanisms involved (Raisz, 2005; Sambrook and Cooper, 2006). Cell studies on the origin of postmenopausal osteoporosis initially focused on osteoclastic activity and bone resorption processes; then on osteoblastogenesis, and more recently on the differentiation potential of mesenchymal stem cells (MSCs) (Shoback, 2007). Moreover, distinctive environmental bone marrow conditions appear to provide support for the development and maintenance of unbalanced bone formation and resorption (Nuttall and Gimble, 2004; Tontonoz et al., 1994). In this review, we consider the participation of the differentiation potential of MSCs, the activity of bone marrow adipocytes and the generation of a distinctive bone marrow microenvironment.

MESENCHYMAL STEM CELLS (MSCs)

Bone marrow contains stem-like cells that are precursors of nonhematopoietic tissues. These cells were initially referred to as plastic-adherent cells or colony forming-unit fibroblasts and subsequently as either mesenchymal stem cells or marrow stromal cells (MSCs) (Minguell et al., 2001; Lindnera et al., 2010; Kolf et al., 2007). There is much interest in these cells because of their ability to serve as a feeder layer for the growth of hematopoietic stem cells, their multipotentiality for differentiation, and their possible use for both cell and gene therapy (Minguell et al., 2001; Kolf et al., 2007). Friedenstein et al. (1970) initially isolated MSCs by their adherence to tissue culture surfaces, and essentially the same protocol has been used by other investigators. The isolated cells were shown to be multipotential in their ability to differentiate in culture or after implantation in vivo, giving rise to osteoblasts, chondrocytes, adipocytes, and/or myocytes.

MSCs populations in the bone marrow or those that are isolated and maintained in culture are not homogenous, but rather consist of a mixture of uncommitted, partially committed and committed progenitors exhibiting divergent stemness (Baksh et al., 2004). These heterogeneous precursor cells are morphologically similar to the multipotent mesenchymal stem cells, but differ in their gene transcription range (Baksh et al., 2004). It has been proposed that in such populations, cell proliferation, differentiation and maturation are in principle independent; stem cells divide without maturation, while cells close to functional competence may mature, but do not divide (Song et al., 2006).

Several molecular markers identify committed progenitors and the end-stage phenotypes, but at present there are no reliable cell markers to identify the uncommitted mesenchymal stem cells. Given the difficulty to identify a single marker to evaluate the population of stem cells, various combinations of these markers may be used (Seo et al., 2004; Lin et al., 2008; Xu et al., 2009). Therefore, MSCs are mainly defined in terms of their functional capabilities: self-renewal, multipotential differentiation and transdifferentiation (Baksh et al., 2004).

Hypothetically, the fate of MSCs appears to be determined during very early stages of cell differentiation ("commitment"). During this mostly unknown period, both intrinsic (genetic) and environmental (local and/or systemic) conditions interplay to outline the cell's fate towards one of the possible lineages. Based on microarray assays comparing gene expression at the stem state and throughout differentiation, it has been proposed that MSCs multilineage differentiation involves a selective mode of gene expression (Baksh et al., 2004; Song et al., 2006). It appears that "stemness" is characterized by promiscuous gene expression, where pluripotential differentiation results from the maintenance of thousands of genes at their intermediate expression levels. Upon commitment to one fate, only the few genes that are needed for differentiation towards the target tissue are selected for continuous expression, while the rest are downregulated (Zipori, 2005; Zipori, 2006).

The gene expression profile of undifferentiated human MSCs (h-MSCs) show high expression of several genes (Song et al., 2006; Tremain et al., 2001), but the contribution of such genes in preserving h-MSC properties, such as self-renewal and multilineage differentiation potential, or in regulating essential signalling pathways is largely unknown (Song et al., 2006). Several factors like age (Zhou et al., 2008), culture condition (Kultere et al., 2007), microenvironment (Kuhn and Tuan, 2010), mechanical strain (McBride et al., 2008) and some pathologies (Seebach et al., 2007; Hofer et al., 2010) appear to affect MSCs' intrinsic activity.

MSCs' commitment towards either the osteoblast or adipocyte lineage is determined by a combination of regulatory factors in the cells' microenvironment. The adequate combination leads to the activation of lineage-specific transcriptional regulators, including Runx2, Dlx5, and osterix for osteoblasts, and PPARy2 and a family of CAAT enhancer binding proteins for adipocytes (Murunganandan et al., 2009). Although the appropriate collection of regulatory factors required for suitable differentiation of MSCs is largely unknown, the TGF/BMPs, Wnt and IGF-I signals are briefly considered.

Several components of the BMP family are secreted in the MSCs' microenvironment (Lou et al., 1999, Gori et al., 1999; Gimble et al., 1995); BMP-2/4/6/7 have been identified as mediators for MSCs differentiation into osteoblasts or adipocytes (Muruganadan et al., 2009). The intracellular effects of BMPs are mediated by an interaction with cell surface BMP receptors (BMPRs type I and type II) (Gimble et al., 1995). It seems that differentiation into adipocytes or osteoblasts is highly dependent on the type of receptor I expressed by the cells, so that adipogenic differentiation requires signaling through BMPR IA, while osteogenic differentiation is dependent on BMPR IB activation (Gimble et al., 1995). The active receptors trigger the activation of Smad proteins, which induce specific genes. Under osteogenic differentiation, BMP action promotes osterix formation through Runx2-dependent and Runx2-independent pathways, thereby triggering osteogenic differentiation (Gori et al., 1999; Shapiro, 1999).

In addition to the role of BMPs in bone formation, BMPs also positively mediate the adipogenic differentiation pathways (Haiyan et al., 2009). It has been demonstrated that there is a binding site for Smad proteins in the promoter region of PPARy2 (Lecka-Czernik et al., 1999), and over-expression of Smad2 protein suppresses the expression of Runx2 (Li et al., 1998). These observations suggest that adequate content of osteoblasts and adipocytes in the bone marrow is dependent on balanced signaling through this pathway. Moreover, considering the distinct role assigned to BMPRIA and BMPRIB, the temporal gain or loss of a subtype of BMP receptors by MSCs could be critical for commitment and subsequent differentiation (Gimble et al., 1995144).

Wnt signaling in MSCs is also decisive for the reciprocal relationship among the osteo/adipogenic pathways. Activation of the Wnt/p-catenin pathway directs MSCs differentiation towards osteoblasts instead of adipocytes (Bennett et al., 2005; Ross et al., 2000; Moldes et al., 2003). Animal studies have shown that activation of the Wnt signaling pathway increases bone mass, preventing both hormone-dependent and age-induced bone loss (Bennett et al., 2005). Furthermore, Wnt activation may control cell commitment towards osteoblasts by blocking adipogenesis through the inhibition of the expression of both C/EBP and PPARy adipogenic transcription factors, as demonstrated in vivo in humans (Qiu et al., 2007), in transgenic mice expressing Wnt 10b (Bennett et al., 2005) and in vitro (Rawadi et al., 2003). MSCs' self-renewing and maintenance of the undifferentiated state appear to be dependent on appropriate canonical Wnt signaling, promoting increased proliferation and decreased apoptosis (Boland et al., 2004; Cho et al., 2006). The overexpression of LRP5, an essential co-receptor specifically involved in canonical Wnt signaling, has been reported to increase proliferation of MSCs (Krishnan et al., 2006). In addition, disruption in vivo or in vitro of -catenin signaling promoted spontaneous conversion of various cell types into adipocytes (Bennett et al., 2002). Moreover, the importance of this pathway for bone mineral density has been highlighted by the observation that genetic variations at either the LRP5 or Wnt10b gene locus are associated with osteoporosis (Brixen et al., 2007; Usui et al., 2007).

Also, insulin-like growth factor-I (IGF-I) signalling is clearly an important factor in skeletal development. The IGF regulatory system consists of IGFs (IGF-I and IGF-II), Type I and Type II IGF receptors, and regulatory proteins including IGF-binding proteins (IGFBP-1-6) and the acid-labile subunit (ALS) (Rosen et al., 1994). The ligands in this system (i.e. IGFs) are potent mitogens, and in some circumstances differentiation factors, that are bound in the circulation and interstitial fluid as binary (to IGFBPs) or ternary complexes (IGF-ALS-IGFBP-3 or -5) with little free IGF-I or -II. IGF bio-availability is regulated by the interaction of these molecules at the receptor level; hence changes in any component of the system will have profound effects on the biologic activity of the ligand. The IGFBPs have a particularly important role in regulating IGF-I access to its receptor, since their binding affinity exceeds that of the IGF receptors. The IGF system is unique because the IGFBPs are regulated in a cell-specific manner at the pericellular microenvironment, such that small changes in their concentrations could strongly influence the mitogenic activity of IGF-I (Jones and Clemmons, 1995; Hwa and Rosenfeld, 1999; Firth and Baxter, 2002). IGFs are expressed virtually by all tissues, and circulate in high concentrations. Although nearly 80% of the circulating IGF-I comes from hepatic sources, both bone and fat synthesize IGF-I and these tissues contribute to the total circulating pool. Locally produced IGF-I predominates over circulating IGF-I in maintaining skeletal integrity (Rosen et al., 1994; Kawai and Rosen, 2010), and both ALS and IGFBP-3 participate in regulating bone function. However, the possible autocrine/paracrine roles of IGF-I and IGFBPs in marrow (Liu et al., 1993; Peng et al., 2003) or in osteoblast (Zhao et al., 2000; Zhang et al., 2002; Wang et al., 2007) are practically unknown.

RELATIONSHIP BETWEEN THE OSTEO- / ADIPOGENESIS PROCESSES - THE FAT THEORY FOR OSTEOPOROSIS

Since in the bone marrow MSCs are the common precursor cells for osteoblast and adipocytes, adequate osteoblast formation requires diminished adipogenesis. As pointed out above, MSCs commitment and differentiation into a specific phenotype depends on hormonal and local factors (paracrine/autocrine) regulating the expression and/or activity of master differentiation genes (Nuttall and Gimble, 2004; Muruganadan et al., 2009) (Figure 1). A reciprocal relationship has been postulated to exist between the two differentiation pathways whose alteration would facilitate adipose accretion in the bone marrow, at the expense of osteoblast formation, thus decreasing bone mass (Reviewed in Rosen et, al 2009; Rodrguez et al.. 2008; Rosen and Bouxtein, 2006). Such unbalanced conditions prevail in the bone marrow of osteoporosis patients, upsetting MSC activity and the microenvironment (Nuttall and Gimble, 2004; Moerman et al., 2004; Rosen and Bouxtein, 2006). This proposition is known as the fat theory for osteoporosis. Moreover, this alteration of osteo-/adipogenic processes is also observed in other conditions characterized by bone loss, such as aging, immobilization, microgravity, ovariectomy, diabetes, and glucocorticoid or tiazolidindione treatments, highlighting the harmful consequence of marrow adipogenesis in osteogenic disorders (Wronski et al., 1986; Moerman et al., 2004; Zayzafon et al., 2004; Forsen et al., 1999).

Cell studies comparing the differentiation potential of MSCs derived from osteoporotic patients (o-MSCs) with that of control MSCs (c-MSCs) have shown unbalanced osteogenic/adipogenic processes, including increased adipose cell formation, counterbalanced by reduced production of osteogenic cells (Nuttall and Gimble, 2004; Rodrguez et al., 2008; Rosen and Bouxtein, 2006). Further research on MSC differentiation has shown that activation of PPARy2, a master transcription factor of adipogenic differentiation, positively regulates adipocyte differentiation while acting as a dominant negative regulator of osteogenic differentiation (Lecka-Czernik et al., 1999; Jeon et al., 2003; Khan and Abu-Amer, 2003). In contrast, an increase in bone mass density was observed in a PPARy deficient mice model; even the heterozygous deficient animals showed high bone mass and increased osteoblastogenesis (Cock et al., 2004). On the other hand, Runx2 expression by MSCs inhibits their differentiation into adipocytes, as may be concluded from experiments in Runx2-/- calvarial cells, which spontaneously differentiate into adipocytes (Kobayashi et al., 2000).

In vivo observations further support the fat theory. Early studies observed that osteoporosis was strongly associated with bone marrow adipogenesis. Iliac crest biopsies showed that bone marrow from osteoporotic patients had a considerable accumulation of adipocytes in relation to that of healthy elderly women (Moerman et al., 2004; Meunier et al., 1971). More recently, increased bone marrow adiposity measured by in vivo proton magnetic resonance (1H-MRS) has been associated with decreased bone mineral density in patients with low bone density (Griffith et al., 2005; Yeung et al., 2005; Blake et al., 2008).

In newborn mammals there is no marrow fat; however the number of adipocytes increases with age such that in humans over 30 years of age, most of the femoral cavity is occupied by adipose tissue (Moore and Dawson, 1990). The function of marrow fat is largely unknown; in humans it was first considered to be 'filler' for the void left by trabecular bone during aging or after radiation. Later, these cells have been proposed to have a role as an energy source, or as modulators of adjacent tissue by the production of paracrine, and autocrine factors (reviewed in Rosen et al., 2009). In fact, adipokines, steroids, and cytokines (Lee et al., 2002; Pino et al., 2010; Rosen et al., 2009;) can exert profound effects on neighboring marrow cells, sustaining or suppressing hematopoietic and osteogenic processes (Omatsu et al., 2010; Krings et al., 2012; Rosen et al., 2009; Rodrguez et al., 2008).

Thus, the function of bone marrow adipose tissue may be similar to that of extra medullary fat. As such, it has been well established that unbalanced production of signaling products from subcutaneous or visceral fat modulates several human conditions including obesity, lipodystrophy, atherogenesis, diabetes and inflammation. Recent studies in mice, suggest a complex fat phenotype in the bone marrow, presenting mixed brown and white adipose properties (Lecka-Czernik, 2012). Further work is needed to find out whether differences in the quality or quantity of marrow fat, take part in deregulated bone remodelling in some bone diseases.

STUDIES ON THE ACTIVITY OF OSTEOPOROTIC MSCs

Because of their ability to self-renew, human MSCs can be expanded and differentiated in vitro, offering many perspectives for tissue engineering and regenerative medicine approaches. However, there is scarce information on whether specific diseases affect the properties of MSCs, because of the difficult accessibility to human bone marrow in health and disease (Cipriani et al., 2011; Corey et al., 2007).

Our research has focused on the properties of MSCs isolated from bone marrow of control and osteoporotic post-menopausal women. We grouped our observations on functional characteristics of o-MSCs and c- MSCs in three categories, which are summarized in Table I, as follows:

General activities: h-MSCs isolated from osteoporotic and control donors have similar CFU-F, but different proliferation rates. O-MSCs showed significantly diminished proliferation rate and decreased mitogenic response to IGF-I. The pERK/ERK ratio is increased in o-MSCs, compared with control c-MSCs. In other cell types, activation of the MEK/ERK signalling pathway enhances the activity of adipogenic transcription factors (Prusty et al., 2002). We also observed decreased TGF- production by o-MSCs, as well as decreased capacity to generate and maintain a type I collagen-rich extracellular matrix, both conditions supporting cell differentiation into the adipocyte phenotype. Then, considering that the lineage fate of MSCs is dependent on early activation by specific BMPs, PPARy and Wnt signaling (Ross et al., 2000; Rawadi et al., 2003; Westendorf et al., 2004; Baron and Rawadi, 2007), we compared the expression level of some genes related to these pathways in c- and o- MSCs. Results obtained by RT-PCR showed that in c- and o-MSCs the expression level of mRNA for -catenin, Dkk-1, and BMPRIB was similar; while the level of mRNA for Wnt 3a was undetectable in both types of samples. The expression level of mRNA for GSK-3p, LRP6 and Osx was lower in o-MSCs than in c-MSCs, while the mRNA level for Ror2, Wnt 5a, BMPRIA showed doubtful. To further quantify the expression level of GSK-3P, LRP6, Osx, Ror2, Wnt 5a, BMPRIA real time RT-PCR was performed. As shown in Table I, statistically significant decreased mRNA levels for GSK-3p, LRP6 and Osx (0.64, 0.26 and 0.18 fold, respectively) were observed in o-MSCs, as compared to c-MSCs. In addition, mRNA levels for Ror2, Wnt 5a, and BMPRIA were similar in both types of cell samples.

These data suggest impaired regulation by the BMPs and Wnt pathways in o-MSCs, representing some intrinsic deviation from control cells that might underlie the impaired self-renewal, and adipogenic/osteogenic differentiation potential observed in o-MSCs. mRNA levels for Ror2, Wnt 5a, and BMPRIA were similar in both types of cell samples.

STUDIES ON THE ACTIVITY OF BONE MARROW FLUID OF POST-MENOPAUSAL WOMEN

Distinctive environmental bone marrow conditions appear to support the development and maintenance of the balance between bone resorption and bone formation. Knowledge is scarce about the intramedullar concentration of compounds with recognized regulatory effects on bone formation or resorption and is limited to some pathologic conditions or estimated from measurements in plasma (Wiig et al., 2004; Iversen and Wiig, 2005; Lee et al., 2002; Khosla et al., 1994).

Measurement of soluble molecules found in human bone marrow has been particularly difficult, not only because of tissue seclusion, but also because of the complicated anatomy and blood perfusion of bone. Since it may be expected that concentrations measured in the bone marrow fluid (BMF) more reliably reflect the physiologically relevant levels in the interstitial compartment surrounding the bone cells than values found in blood, we isolated the extracellular bone marrow fluid by directly spinning bone marrow samples for 20 min at 900xg. Considering the complex organization in such a regulatory milieu, we opted for evaluating some molecules recognized as markers of adipocyte, proinflammatory or osteoclastic/osteoblastic activity (Pino et al., 2010).

The concentrations of cytokines or receptors measured in the bone marrow extracellular fluid from control and osteoporotic human donors are indicated in Table II. In addition, the concentrations of IGF-I and its IGFBPs were analyzed, as well as the C-terminal telopeptide cross-links of type I collagen (CTX). Results summarized in Table II indicate significantly different concentrations of regulatory molecules in the extracellular fluid of control versus osteoporotic women; this last group was characterized by higher content of proinflammatory and adipogenic cytokines. Also, osteoporotic samples showed decreased leptin bioavailability, suggesting that insufficient leptin action may characterize the osteoporotic bone marrow (Pino et al., 2010). In addition, bioavailability of IGF-I appears diminished in o-BMF, as shown by the increased IGFBP3/IGF-I ratio.

TABLE II

Regulatory activity in bone marrow fluid of post-menopausal women

Taken together our results and those of other researchers identify significant differences between functional properties of control and osteoporotic MSCs, displayed in vitro, in cells under basal or differentiating conditions. Moreover, it can be concluded that such divergence prevails also in vivo, because the bone marrow fluid of osteoporotic patients characterizes by unfavourable content of several regulatory molecules. Therefore, the properties of both MSCs and bone marrow microenvironment are significantly impaired in osteoporotic patients, negatively affecting bone formation.

CONCLUSIONS

In the pathogenesis of osteoporosis, impairment of both MSCs functionality and microenvironment add to the known detrimental effect of increased osteoclast activity, resulting in decreased bone formation.

O-MSCs are characterized by intrinsic functional alteration leading to poor osteogenic capability and increased adipogenesis. Osteoporotic bone marrow microenvironment differs from the control microenvironment by increased concentration of pro-adipogenic and pro-inflammatory regulatory factors.

The content and/or quality of adipocytes in the bone marrow appear critical to delineate impairing of MSCs; in this sense osteoporosis could be homologated to other age-related diseases such as obesity, atherogenesis and diabetes, which are characterized by extramedullar unbalanced adipocyte formation and signaling.

Currently it is not known how damaged o-MSCs emerge, further work is needed to ascertain the role of the microenvironment, and genetic and epigenetic factors, as proposed for other stem cells-related pathologies.

The conclusion that intrinsic properties of MSCs are altered in osteoporosis should be relevant for the therapeutic use of MSCs, which represent an interesting promise for regenerative medicine for several severe human diseases.

The possibility of reversing o-MSCs impairment opens new perspectives for osteoporosis therapy.

ACKNOWLEDGEMENTS

We thank Dr. Mariana Cifuentes for her critical review of the manuscript and valuable comments. This work was supported by a grant from the Fondo Nacional de Ciencia y Tecnologa (FONDECYT # 1090093)

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In Osteoporosis, differentiation of mesenchymal stem cells ...

Bone Marrow Stem Cells Comments Off on In Osteoporosis, differentiation of mesenchymal stem cells … | August 30th, 2017

On Monday, the U.S. Food and Drug Administration (FDA) announced that the agency is targeting clinics that offer unproven stem cell therapies, calling such offices "unscrupulous clinics" selling "so-called cures." The FDA seized materials from one clinic in California, and sent a warning letter to another in Florida.

The FDA will not allow deceitful actors to take advantage of vulnerable patients by purporting to have treatments or cures for serious diseases without any proof that they actually work," said FDA Commissioner Dr. Scott Gottlieb in a statement.

The agency announced that on Friday, Aug. 25th, U.S. Marshals seized five vials of a vaccine that is intended for people at a high risk for smallpox (for example, people in the military) from StemImmune Inc. in San Diego, California. The FDA says it learned that StemImmune was using the vaccines as well as stem cells from body fat to create an unapproved stem cell therapy. On its website, StemImmune says "The patients own (autologous, adult) stem cells, armed with potent anti-cancer payloads, function like a Trojan Horse, homing to tumors and cancer cells, undetected by the immune system." The stem cell treatment was injected into the tumors of cancer patients at the California Stem Cell Treatment Centers in Rancho Mirage and Beverly Hills, California.

MORE: Three People Are Nearly Blind After Getting a Stem Cell Treatment

The FDA also sent a warning later to U.S. Stem Cell Clinic in Sunrise, Florida. The company recently came under public scrutiny when a March report revealed that three people had severe damage to their vision one woman went blindafter they were given shots of what the company said were stem cells into their eyes during a study sponsored by the clinic. The FDA says that an inspection of U.S. Stem Cell Clinic revealed that the clinic was using stem cells to treat diseases like Parkinson's, amyotrophic lateral sclerosis (ALS), chronic obstructive pulmonary disease (COPD), heart disease and pulmonary fibrosis. According to the FDA, there are currently only a limited number of stem cell therapies approved by the agencyincluding ones involving bone marrow, for bone marrow transplants in cancer care, and cord blood for specific blood-related disorders. There are no approved stem cell treatments for other diseases.

The FDA says U.S. Stem Cell Clinic also attempted to interfere with the FDA's most recent inspection by refusing to allow FDA investigators to enter without an appointment, and denied the agency access to its employees. "Refusing to permit entry or FDA inspection is a violation of federal law," the FDA says.

Action by the FDA on clinics promoting unproven stem cell therapies is "a long time coming," says Sean Morrison, former president of the International Society for Stem Cell Research (ISSCR) and d irector of the Childrens Research Institute at UT Southwestern. "C linics are preying on the hopes of desperate patients claiming they can cure all manner of diseases with stem cells that have not been tested in clinical trials, and in some cases, are flat out impossible."

In the past, medical experts were concerned over Americans traveling to countries with less medical regulation for stem cell therapies, but Morrison says such clinics have been popping up stateside over the last five years. "It's not a few companies in the U.S. making claims about therapies with stem cells," says Morrison. "It's scores of companies. The problem has exploded in the U.S."

Morrison blames the lack of FDA crackdown in the past for the growing problem. "At some point people made the calculation that the FDA didnt seem to be enforcing these laws," he says. "The margins are huge. They charge people tens of thousands of dollars."

Since stem cell therapy is still an active and legitimate area of scientific research, it can be hard for Americans to figure out what is safe and effective and what is not. Even when it comes to clinical trials, the scientific soundness is murky. A July 2017 paper reported that 18 U.S. companies have registered "patient-sponsored" stem cell studies on ClinicalTrials.gov. That means that the patients receiving the treatment paid for them, which isn't the case in more legitimate studies. None of these were gold standard studies: meaning the people were not randomly assigned to receive the treatment or not, so the participants knew they were receiving the therapy that could bias the results. Only seven of the studies disclosed upfront that patients had to pay to join the study, and none revealed that the costs ranged from $5,000 to $15,000 a treatment, Wired reports.

While Morrison says he's glad the FDA has taken action, he says it's not enoughat least not yet. "The FDA has to show that there is really a sustained commitment to enforcement," he says. "When the FDA wasnt bringing actions against these companies, I think people thought this meant that it was a gray area and that they could get away with it."

Undoing that damage could be a long process, and one that Morrison says needs consistent attention by the agency. In a letter released on Monday, FDA commissioner Gottlieb said the agency is stepping up enforcement of stem cell therapies and regenerative medicine. "Ive directed the FDA to launch a new working group to pursue unscrupulous clinics through whatever legally enforceable means are necessary to protect the public health," said Gottlieb. Whether those efforts have an impact remains to be seen.

Excerpt from:
FDA Cracks Down on Stem Cell Clinics But Patients Are Still at Risk - TIME

Bone Marrow Stem Cells Comments Off on FDA Cracks Down on Stem Cell Clinics But Patients Are Still at Risk – TIME | August 30th, 2017

A new review looks at the potential of fetal membranes, which make up the amniotic sac surrounding the fetus during pregnancy, for regenerative medicine.

Fetal membranes have been used as biological bandages for skin grafts as well as for serious burns. They may also have numerous other applications because they contain a variety of stem cells, which might be used to treat cardiovascular and neurological diseases, diabetes, and other medical conditions.

"The fetal membranes have been used successfully in medical applications for over a century, but we continue to discover new properties of these membranes," said Dr. Rebecca Lim, author of the STEM CELLS Translational Medicine review. "The stem cell populations arising from the fetal membranes are plentiful and diverse, while the membrane itself serves as a unique biocompatible scaffold for bioengineering applications."

Explore further: Stem cell research could prevent premature births

More information: Rebecca Lim. Concise Review: Fetal Membranes in Regenerative Medicine: New Tricks from an Old Dog?, STEM CELLS Translational Medicine (2017). DOI: 10.1002/sctm.16-0447

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Fetal membranes may help transform regenerative medicine - Medical Xpress

Bone Marrow Stem Cells Comments Off on Fetal membranes may help transform regenerative medicine – Medical Xpress | August 30th, 2017

A diagram of a scaffold loaded with CAR T cells and microspheres containing nutrients to help the cells multiply and then leave the scaffold to go attack cancer cells. Credit: Cognition Studio, courtesy of Fred Hutchinson Cancer Research Center.

A new biomedical tool using nanoparticles that deliver transient gene changes to targeted cells could make therapies for a variety of diseasesincluding cancer, diabetes and HIVfaster and cheaper to develop, and more customizable.

The tool, developed by researchers at Fred Hutchinson Cancer Research Center and tested in preclinical models, is described in a paper published August 30 in Nature Communications.

"Our goal is to streamline the manufacture of cell-based therapies," said lead author Dr. Matthias Stephan, a faculty member in the Fred Hutch Clinical Research Division and an expert in developing biomaterials. "In this study, we created a product where you just add it to cultured cells and that's itno additional manufacturing steps."

Stephan and his colleagues developed a nanoparticle delivery system to extend the therapeutic potential of messenger RNA, which delivers molecular instructions from DNA to cells in the body, directing them to make proteins to prevent or fight disease.

The researchers' approach was designed to zero in on specific cell typesT cells of the immune system and blood stem cellsand deliver mRNA directly to the cells, triggering short-term gene expression. It's called "hit-and-run" genetic programming because the transient effect of mRNA does not change the DNA, but it is enough to make a permanent impact on the cells' therapeutic potential.

Stephan and colleagues used three examples to demonstrate their technology:

Other attempts to engineer mRNA into disease-fighting cells have been tricky. The large messenger molecule degrades quickly before it can have an effect, and the body's immune system recognizes it as foreignnot coming from DNA in the nucleus of the celland destroys it.

Stephan and his Fred Hutch collaborators devised a workaround to those hurdles.

"We developed a nanocarrier that binds and condenses synthetic mRNA and protects it from degradation," Stephan said. The researchers surrounded the nanoparticle with a negatively charged envelope with a targeting ligand attached to the surface so that the particle selectively homes in and binds to a particular cell type.

The cells swallow up the tiny carrier, which can be loaded with different types of manmade mRNA. "If you know from the scientific literature that a signaling pathway works in synergy, you could co-deliver mRNA in a single nanoparticle," Stephan said. "Every cell that takes up the nanoparticle can express both."

The approach involves mixing the freeze-dried nanoparticles with water and a sample of cells. Within four hours, cells start showing signs that the editing has taken effect. Boosters can be given if needed. Made from a dissolving biomaterial, the nanoparticles are removed from the body like other cell waste.

"Just add water to our freeze-dried product," Stephan said. Since it's built on existing technologies and doesn't require knowledge of nanotechnology, he intends for it to be an off-the-shelf way for cell-therapy engineers to develop new approaches to treating a variety of diseases.

The approach could replace labor-intensive electroporation, a multistep cell-manufacturing technique that requires specialized equipment and clean rooms. All the handling ends up destroying many of the cells, which limits the amount that can be used in treatments for patients.

Gentler to cells, the nanoparticle system developed by the Fred Hutch team showed that up to 60 times more cells survive the process compared with electroporation. This is a critical feature for ensuring enough cells are viable when transferred to patients.

"You can imagine taking the nanoparticles, injecting them into a patient and then you don't have to culture cells at all anymore," he said.

Stephan has tested the technology is cultured cells in the lab, and it's not yet available as a treatment. Stephan is looking for commercial partners to move the technology toward additional applications and into clinical trials where it could be developed into a therapy.

Explore further: Implanted scaffold with T cells rapidly shrinks tumors

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Nanoparticles loaded with mRNA give disease-fighting properties to cells - Medical Xpress

Bone Marrow Stem Cells Comments Off on Nanoparticles loaded with mRNA give disease-fighting properties to cells – Medical Xpress | August 30th, 2017

Essentially, nanoparticles carried a gene-editing tool to T cells of the immune system that snipped out their natural T-cell receptors, and then was paired with genes encoding a chimeric antigen receptor, or CAR, a synthetic molecule designed to attack cancer.

Next, nanoparticles were targeted to blood stem cells and equipped with mRNA that enabled the stem cells to multiply and replace blood cancer cells with healthy cells when used in bone marrow transplants.

Finally, nanoparticles were targeted to CAR T cells and equipped with Foxo1 mRNA, which signals the anticancer T cells to develop into a type of "memory" cell that is more aggressive and destroys tumor cells more effectively and maintains antitumor activity longer.

"Our goal is to streamline the manufacture of cell-based therapies," said lead author Matthias Stephan, M.D., Ph.D., a faculty member in the Fred Hutch Clinical Research Division and an expert in developing biomaterials. "In this study, we created a product where you just add it to cultured cells and that's itno additional manufacturing steps."

Dr. Stephan and his colleagues developed a nanoparticle delivery system to extend the therapeutic potential of mRNA, which delivers molecular instructions from DNA to cells in the body, directing them to make proteins to prevent or fight disease.

The researchers' approach was designed to zero in on specific cell typesT cells of the immune system and blood stem cellsand deliver mRNA directly to the cells, triggering short-term gene expression. It's called "hit-and-run" genetic programming because the transient effect of mRNA does not change the DNA, but it is enough to make a permanent impact on the cells' therapeutic potential.

Other attempts to engineer mRNA into disease-fighting cells have been tricky. The large messenger molecule degrades quickly before it can have an effect, and the body's immune system recognizes it as foreignnot coming from DNA in the nucleus of the celland destroys it.

Stephan and his Fred Hutch collaborators devised a workaround to those hurdles.

"We developed a nanocarrier that binds and condenses synthetic mRNA and protects it from degradation," Dr. Stephan explained. The researchers surrounded the nanoparticle with a negatively charged envelope with a targeting ligand attached to the surface so that the particle selectively homes in and binds to a particular cell type.

The cells swallow up the tiny carrier, which can be loaded with different types of man-made mRNA. "If you know from the scientific literature that a signaling pathway works in synergy, you could co-deliver mRNA in a single nanoparticle," Dr. Stephan elaborated. "Every cell that takes up the nanoparticle can express both."

The approach involves mixing the freeze-dried nanoparticles with water and a sample of cells. Within four hours, cells start showing signs that the editing has taken effect. Boosters can be given if needed. Made from a dissolving biomaterial, the nanoparticles are removed from the body like other cell waste.

"Just add water to our freeze-dried product," Dr. Stephan emphasized. Since it's built on existing technologies and doesn't require knowledge of nanotechnology, he intends for it to be an off-the-shelf way for cell-therapy engineers to develop new approaches to treating a variety of diseases.

The approach could replace labor-intensive electroporation, a multistep cell-manufacturing technique that requires specialized equipment and clean rooms. All the handling ends up destroying many of the cells, which limits the amount that can be used in treatments for patients.

Gentler to cells, the nanoparticle system developed by the Fred Hutch team showed that up to 60 times more cells survive the process compared with electroporation. This is a critical feature for ensuring enough cells are viable when transferred to patients.

"You can imagine taking the nanoparticles and injecting them into a patient; then you don't have to culture cells at all anymore," he asserted.

Dr. Stephan has tested the technology in cultured cells in the lab, but it's not yet available as a treatment. He is looking for commercial partners to move the technology toward additional applications and into clinical trials where it could be developed into a therapy.

More here:
Cell Therapy Can Be Fast and Easy: Just Add mRNA Nanocarriers - Genetic Engineering & Biotechnology News

Bone Marrow Stem Cells Comments Off on Cell Therapy Can Be Fast and Easy: Just Add mRNA Nanocarriers – Genetic Engineering & Biotechnology News | August 30th, 2017

Resident Asma Mursleen, MD (center) with Roseanne C. Berger, MD (left), and Michael E. Cain, MD was honored for her research at the 20th annual Scholarly Exchange Day.

Published August 30, 2017

Trainees and a student in the departments of Medicine, BiomedicalEngineering and Pediatrics havereceived awards for their research.

Hem-Onc, Medicine Trainees Receive Frawley

The two trainees to receive support from theThomasF. Frawley, MD, Residency Research FellowshipFundare:

Asma Mursleen, MDResident in theDepartment ofMedicineProject Title: Defining the Role of CDC-derived Exosomes onMacrophage Polarization and Modulation of CardioprotectionFollowing Myocardial Infarction

Amanda Przespolewski, DOA 2017 alumna of the hematology/oncologyfellowshipProject title: Dual Enhancement of Immune Responses andInhibition of Marrow Vasculature in Acute MyeloidLeukemia

The awardsupports medical or surgical residents, fellowsand new graduates for whom research represents a primary interestand passion.

Frawley, a 1944 graduate of the medical school, was a nationallyrecognized endocrinology researcher, president of the AmericanCollege of Physicians and chair of medicine at Saint LouisUniversity School of Medicine.

Student and Faculty Member Win Mindell/Brody

The 2017 recipients of the EugeneR. Mindell, MD, and Harold Brody, MD 61, PhD, ClinicalTranslational Research Awardare:

YonghoBae, PhD Assistant professor in theDepartment ofPathology and Anatomical Sciences Project Title: Effect of Arterial Stiffening onVascular Smooth Muscle Cell Mechanotransduction

Kyle Indiana MentkowskiMasters candidate in the Departmentof Biomedical EngineeringProject Title: Development of a Targeted CardiomyocyteDelivery System Utilizing Cardiosphere-Derived CellExosomes

The award recognizes junior research scientists for the bestbasic science research that seeks to solve a clinical problem.

Mindell chairedUBs Department ofOrthopaedics from 1964 to 1988. A past president of theAmerican Board of Orthopaedic Surgery, he is creditedwithinitiating the boards certifying process fororthopaedic surgeons.

Brody was the chair of anatomy and cell biology from 1971 to1992. He founded UBs BrainMuseum, a world-class collection of brain specimens andslides.

Pediatrics, Medicine Residents Receive Calkins

The 2017 honorees for the EvanCalkins, MD, Fellowship for Community-BasedResearchare:

Raed Al Yacoub, MD Resident in the Department ofMedicineProject Title: Enhancing the Prevention of MicrovascularComplications of Diabetes Type 2: A Resident-Led QIProject

Prerana Baranwal, MDResident in the Department ofPediatricsProject Title: Addressing Childhood Obesity ThroughDyslipidemia Screening: Measuring Frequency of DyslipidemiaScreening with Substitution of Random Lipid Panel for Fasting LipidPanel

The award supports residents, fellows and junior faculty whoconduct community-based research or quality improvementprojects.

Calkins was chair of the UB Department of Internal Medicine,division chief of geriatrics and founder of the geriatricsfellowship. He served as director of medicine at Meyer MemorialHospital (now Erie County Medical Center) for 12 years.

The award is a product of his conviction that medicalinstitutions have an obligation to improve the quality of, andaccess to, health care throughout the community.

Fellow Receives Honorable Mention

Amro Elshoury, MBBCh, a trainee in the hematology/oncologyfellowship, received an honorable mention for the Frawleyaward. Elshourys project was: The Effect ofExtra-Physiologic Oxygen Shock / Stress (EPHOSS) On Human BoneMarrow Stem Cell Viability And Multi-Potency.

Awards Presented at Scholarly Exchange Day

RoseanneC. Berger, MD, senior associate dean for graduate medicaleducation, presented the awards at this years ScholarlyExchange Day.

The keynote speaker,StevenD. Schwaitzberg, MD, professor and chair of surgery,presented a talk titled Preparing Students and Residents for21st Century Surgery.

MichaelE. Cain, MD, vice president for health sciences and dean, Jacobs School of Medicine andBiomedical Sciences, gave school updates and introductoryremarks at the event.

Excerpt from:
Frawley, Mindell/Brody, Calkins Awards Recognize 5 for Excellence - UB School of Medicine and Biomedical Sciences News

Bone Marrow Stem Cells Comments Off on Frawley, Mindell/Brody, Calkins Awards Recognize 5 for Excellence – UB School of Medicine and Biomedical Sciences News | August 30th, 2017