Help for a scarred heart: Scarring cells turned to beating …
By NEVAGiles23
Poets and physicians know that a scarred heart cannot beat the way it used to, but the science of reprogramming cells offers hope--for the physical heart, at least.
A team of University of Michigan biomedical engineers has turned cells common in scar tissue into colonies of beating heart cells. Their findings could advance the path toward regenerating tissue that's been damaged in a heart attack.
Previous work in direct reprogramming, jumping straight from a cell type involved in scarring to heart muscle cells, has a low success rate. But Andrew Putnam, an associate professor of biomedical engineering and head of the Cell Signaling in Engineered Tissues Lab, thinks he knows at least one of the missing factors for better reprogramming.
"Many reprogramming studies don't consider the environment that the cells are in -- they don't consider anything other than the genes," he said. "The environment can dictate the expression of those genes."
To explore how the cells' surroundings might improve the efficiency of reprogramming, Yen Peng Kong, a post-doctoral researcher in the lab, attempted to turn scarring cells, or fibroblasts, into heart muscle cells while growing them in gels of varying stiffness. He and his colleagues compared a soft commercial gel with medium-stiffness fibrin, made of the proteins that link with platelets to form blood clots, and with high-stiffness collagen, made of structural proteins.
The fibroblasts came from mouse embryos. To begin the conversion to heart muscle cells, Kong infected the fibroblasts with a specially designed virus that carried mouse transgenes -- genes expressed by stem cells.
Fooled into stem cell behavior, the fibroblasts transformed themselves into stem-cell-like progenitor cells. This transition, which would be skipped in direct reprogramming, encouraged the cells to divide and grow into colonies rather than remaining as lone rangers. The tighter community might have helped to ease the next transition, since naturally developing heart muscle cells are also close with their neighbors.
After seven days, Kong changed the mixture used to feed the cells, adding a protein that encourages the growth of heart tissue. This helped push the cells toward adopting the heart muscle identity. A few days later, some of the colonies were contracting spontaneously, marking themselves out as heart muscle colonies.
The transition was particularly successful in the fibrin and fibrin-collagen mixes, which saw as many as half of the colonies converting to heart muscle.
The team has yet to discover exactly what it is about fibrin that makes it better for supporting heart muscle cell. While most materials either stretch or weaken under strain, fibrin gets harder. Putnam wonders whether the fibrin was successful because heart muscles expect a material that toughens up when they contract.
Go here to read the rest:
Help for a scarred heart: Scarring cells turned to beating ...
Okyanos Heart Institute Hosts Networking Reception for the …
By NEVAGiles23
February 11, 2014 --
Freeport, Bahamas (PRWEB) February 11, 2014
Matt Feshbach, CEO of Okyanos Heart Institute whose mission it is to bring a new standard of care and better quality of life to patients with coronary artery disease using cardiac stem cell therapy, announces the company will host a hard hat reception for conference attendees at their new facility in Freeport. The conference, titled Bridging the Gap: Research to Point of Care, brings together medical scientists, clinicians, regulatory experts, and investors to discuss progress in the field of research and clinical protocols and the process of taking promising therapies to fight chronic disease to market in a responsible manner. Gold Sponsor Okyanos Heart Institute hosts a networking reception for conference attendees at their facility in Freeport on Friday, February 21st from 5:00 7:00 p.m. The company is calling the reception a hard hat reception metaphorically as the construction is not yet completed.
Chief Medical Officer Howard Walpole, M.D., M.B.A., F.A.C.C., F.S.C.A.I. and Chief Science Officer Leslie Miller, M.D., F.A.C.C. will host the reception, along with CEO Matthew Feshbach and offer tours of the commercial cath lab which will offer stem cell therapy to qualified patients with advanced coronary artery disease under the new laws and regulations in The Bahamas.
Douglas Hammond, president of STEMSO, states, STEMSO will continue to provide a proactive and positive voice for organizations and jurisdictions using adult stem cells for therapies and transplants. The Commonwealth of The Bahamas, and our Gold Sponsor Okyanos Heart Institute provide an excellent example of the results that can be brought about with realistic, modern and balanced regulations that serve the national economic interest, patient needs for life-saving medicine and the business advantages for commercialization and translation of adult stem cells.
The reception in our facility will showcase the capabilities in The Bahamas to deliver high quality healthcare to patients in need, says Walpole. It will also provide an informal forum for relevant discussion on bridging the gap between research and point of care between scientists, regulatory experts, clinicians and government officials, and help to address issues of paramount importance such as patient safety and effective tracking of progress once the patients return home. We are proud to host this reception at Okyanos Heart Institute.
Treating patients with adipose-derived stem and regenerative cells (ADRCs) is showing existing promise in clinical trials, states Leslie Miller, M.D., F.A.C.C. an investigator in more than eighty clinical trials for heart failure. The next step in delivering stem cells to patients outside of clinical trials is close. I am enormously excited about the opportunity with this conference to engage in meaningful discussion around what parameters must exist to treat heart failure patients safely and tracking the effectiveness of these new options, which previously were unavailable to patients who have had heart attacks and/or stents, and who continue to worsen after exhausting all other interventions available to them.
The complete agenda for the conference can be found on STEMSOs website at http://www.stemso.org. Other speakers include stem cell researchers, scientists and practitioners from around the world with leading discoveries in the field, and investors in the healthcare space.
Registration is open for attending and exhibiting on STEMSOs website.
About Okyanos Heart Institute: (Oh key AH nos) Based in Freeport, The Bahamas, Okyanos Heart Institutes mission is to bring a new standard of care and a better quality of life to patients with coronary artery disease using cardiac stem cell therapy. Okyanos adheres to U.S. surgical center standards and is led by Chief Medical Officer Howard T. Walpole Jr., M.D., M.B.A., F.A.C.C., F.S.C.A.I. Okyanos Treatment utilizes a unique blend of stem and regenerative cells derived from ones own adipose (fat) tissue. The cells, when placed into the heart via a minimally-invasive catheterization, stimulate the growth of new blood vessels, a process known as angiogenesis. The treatment facilitates blood flow in the heart and supports intake and use of oxygen (as demonstrated in rigorous clinical trials such as the PRECISE trial). The literary name Okyanos (Oceanos) symbolizes flow. For more information, go to http://www.okyanos.com.
Continued here:
Okyanos Heart Institute Hosts Networking Reception for the ...
Okyanos Heart Institute Hosts Networking Reception for the International Stem Cell Society (STEMSO) World Conference …
By daniellenierenberg
Freeport, Bahamas (PRWEB) February 11, 2014
Matt Feshbach, CEO of Okyanos Heart Institute whose mission it is to bring a new standard of care and better quality of life to patients with coronary artery disease using cardiac stem cell therapy, announces the company will host a hard hat reception for conference attendees at their new facility in Freeport. The conference, titled Bridging the Gap: Research to Point of Care, brings together medical scientists, clinicians, regulatory experts, and investors to discuss progress in the field of research and clinical protocols and the process of taking promising therapies to fight chronic disease to market in a responsible manner. Gold Sponsor Okyanos Heart Institute hosts a networking reception for conference attendees at their facility in Freeport on Friday, February 21st from 5:00 7:00 p.m. The company is calling the reception a hard hat reception metaphorically as the construction is not yet completed.
Chief Medical Officer Howard Walpole, M.D., M.B.A., F.A.C.C., F.S.C.A.I. and Chief Science Officer Leslie Miller, M.D., F.A.C.C. will host the reception, along with CEO Matthew Feshbach and offer tours of the commercial cath lab which will offer stem cell therapy to qualified patients with advanced coronary artery disease under the new laws and regulations in The Bahamas.
Douglas Hammond, president of STEMSO, states, STEMSO will continue to provide a proactive and positive voice for organizations and jurisdictions using adult stem cells for therapies and transplants. The Commonwealth of The Bahamas, and our Gold Sponsor Okyanos Heart Institute provide an excellent example of the results that can be brought about with realistic, modern and balanced regulations that serve the national economic interest, patient needs for life-saving medicine and the business advantages for commercialization and translation of adult stem cells.
The reception in our facility will showcase the capabilities in The Bahamas to deliver high quality healthcare to patients in need, says Walpole. It will also provide an informal forum for relevant discussion on bridging the gap between research and point of care between scientists, regulatory experts, clinicians and government officials, and help to address issues of paramount importance such as patient safety and effective tracking of progress once the patients return home. We are proud to host this reception at Okyanos Heart Institute.
Treating patients with adipose-derived stem and regenerative cells (ADRCs) is showing existing promise in clinical trials, states Leslie Miller, M.D., F.A.C.C. an investigator in more than eighty clinical trials for heart failure. The next step in delivering stem cells to patients outside of clinical trials is close. I am enormously excited about the opportunity with this conference to engage in meaningful discussion around what parameters must exist to treat heart failure patients safely and tracking the effectiveness of these new options, which previously were unavailable to patients who have had heart attacks and/or stents, and who continue to worsen after exhausting all other interventions available to them.
The complete agenda for the conference can be found on STEMSOs website at http://www.stemso.org. Other speakers include stem cell researchers, scientists and practitioners from around the world with leading discoveries in the field, and investors in the healthcare space.
Registration is open for attending and exhibiting on STEMSOs website.
About Okyanos Heart Institute: (Oh key AH nos) Based in Freeport, The Bahamas, Okyanos Heart Institutes mission is to bring a new standard of care and a better quality of life to patients with coronary artery disease using cardiac stem cell therapy. Okyanos adheres to U.S. surgical center standards and is led by Chief Medical Officer Howard T. Walpole Jr., M.D., M.B.A., F.A.C.C., F.S.C.A.I. Okyanos Treatment utilizes a unique blend of stem and regenerative cells derived from ones own adipose (fat) tissue. The cells, when placed into the heart via a minimally-invasive catheterization, stimulate the growth of new blood vessels, a process known as angiogenesis. The treatment facilitates blood flow in the heart and supports intake and use of oxygen (as demonstrated in rigorous clinical trials such as the PRECISE trial). The literary name Okyanos (Oceanos) symbolizes flow. For more information, go to http://www.okyanos.com.
Okyanos LinkedIn Page: http://www.linkedin.com/company/okyanos-heart-institute Okyanos Facebook Page: https://www.facebook.com/OKYANOS Okyanos Twitter Page: https://twitter.com/#!/OkyanosHeart Okyanos Google+ Page: https://plus.google.com/+Okyanos/posts Okyanos You Tube Physician Channel: http://www.youtube.com/user/okyanosforphysicians
Excerpt from:
Okyanos Heart Institute Hosts Networking Reception for the International Stem Cell Society (STEMSO) World Conference ...
Heart Stem Cells, LVAD May Avoid Transplants …
By JoanneRUSSELL25
MINNEAPOLIS, Minn. (Ivanhoe Newswire) - Statistics from the Department of Health and Human Services reveal that an average of 18 people dies waiting for organ transplants each day. There are about 2,500 hearts available and a waiting list of about 100,000 patients in need. Now, researchers at the University of Minnesota hope to bridge that gap.
"I couldn't walk, or breathe, or eat," congestive heart failure patient Allan Isaacs told Ivanhoe.
That was life with congestive heart failure for 71-year-old Isaacs, but after a left ventricular assist device was implanted into his chest, Allan's life got moving again.
"(I do)15 minutes on the elliptical and about 30 minutes on the treadmill," Allan said.
The LVAD helps pump oxygen rich blood throughout the body, but Allan's recovery may also have to do with the fact that his treatment may have included injections of his own bone marrow stem cells. Allan's taking part in a leading edge blind study at the University of Minnesota's Medical Center.
"We isolate the stem cells and when they go for surgery we inject those cells on the heart wall," Ganesh Raveendran, MD, MS, Director of the Cardiac Catheterization Laboratory at the University of Minnesota Medical Center, told Ivanhoe.
One-third of the patients receive a placebo, the rest get ten injections of stem cells into their hearts. Muscle tissue is then analyzed to, "see whether these cells have made any meaningful change, whether the cells have transformed into cardiac muscle," Dr. Raveendran explained.
In many cases an LVAD is a bridge to transplant, but researchers and Allan hope this stem cell therapy could eliminate that need.
"Now, I can do whatever I feel like doing," Allan said.
The research team at the University of Minnesota Medical Center hopes to wrap up the study by end of this year and collaborate on a multicenter study involving seven medical centers throughout the nation.
See the original post:
Heart Stem Cells, LVAD May Avoid Transplants ...
UT Arlington bioengineer to create new nanoparticle system to shore up arterial walls
By JoanneRUSSELL25
PUBLIC RELEASE DATE:
3-Feb-2014
Contact: Herb Booth hbooth@uta.edu 817-272-7075 University of Texas at Arlington
A UT Arlington bioengineer has received a four-year, $1.4 million National Institutes of Health grant to create a nanoparticle system to shore up arterial walls following angioplasty and stenting procedures to treat coronary arterial disease.
Kytai Nguyen, a UT Arlington associate professor of bioengineering, said the research looks to improve an established procedure like angioplasty, which opens arteries and blood vessels that are blocked.
"We have discovered a way to use nanoparticles to help the arteries heal themselves more effectively following one of the most common surgical procedures," said Nguyen, who joined UT Arlington in 2005. "This process promises to reduce complications that can occur in the arteries following surgery and may extend opportunities for patients to live longer, healthier lives."
The Centers for Disease Control and Prevention reported that nearly 1 million people in the United States have angioplasty or stent procedures done annually.
Khosrow Behbehani, dean of the College of Engineering, said Dr. Nguyen is specializing in developing innovative techniques for drug delivery which critical to advancing health care.
"Earning a National Institutes of Health grant puts Dr. Nguyen in very exclusive company," Behbehani said. The NIH reported that only 16.8 percent of its nearly 50,000 applications in 2013 were awarded grants. "Receiving this grant reflects the cutting-edge research that Dr. Nguyen is conducting. Her investigation will help improve the efficacy of stents in treating cardiovascular anomalies."
Following the angioplasty or stent, surgeons would insert the nanoparticles at the affected site, and the nanoparticles would attach themselves to the arterial wall. The nanoparticles would be programmed to recruit stem cells, which would regenerate the arterial wall's weakened cells naturally, Nguyen said.
Visit link:
UT Arlington bioengineer to create new nanoparticle system to shore up arterial walls
Engineered Cardiac Tissue Developed to Study the Human Heart
By Dr. Matthew Watson
Contact Information
Available for logged-in reporters only
Newswise When it comes to finding cures for heart disease, scientists at Icahn School of Medicine at Mount Sinai are working to their own beat. They may have developed a tissue model for the human heart that can bridge the gap between animal models and human clinical trial patients.
Mount Sinai researchers generated their engineered cardiac tissue from human embryonic stem cells with the resulting muscle having remarkable similarities to native heart muscle, including the ability to beat and contract like the human heart. This research breakthrough study was highlighted as the cover story of the February 2014 issue of The FASEB Journal.
"We hope that our human engineered cardiac tissues will serve as a platform for developing reliable models of the human heart for routine laboratory use," said lead researcher Kevin D. Costa, PhD, Associate Professor of Cardiology and Director of the Cardiovascular Cell and Tissue Engineering Laboratory at the Cardiovascular Research Center of Icahn School of Medicine at Mount Sinai.
"This could help accelerate and revolutionize cardiology research by improving the ability to efficiently discover, design, develop, and deliver new therapies for the treatment of heart disease, and by providing more efficient screening tools to identify and prevent cardiac side effects, ultimately leading to safer and more effective treatments for patients suffering from heart disease," says Dr. Costa.
The international team of researchers led by Mount Sinai created human engineered cardiac tissue, known as hECTs, within a custom bioreactor device designed to exercise the tissue and measure its contractile force throughout the culture process. Within 7-10 days, the human cardiac cells self-assembled into a three-dimensional tissue strip that beats spontaneously like natural heart muscle, and can survive a month or more for long-term experimental testing. These hECTs displayed contractile activity in a rhythmic pattern of 70 beats per minute on average, similar to the human heart.
In addition, research results show the heart tissue model responds to electrical stimulation and is able to incorporate new genetic information delivered by adenovirus gene therapy. During functional analysis, some of the responses known to occur in the natural adult human heart were also elicited in hECTs through electrical, mechanical, and pharmacological interventions, while some responses of hECTs more closely mimicked the immature or newborn human heart.
"We've come a long way in our understanding of the human heart," said Gerald Weissmann, MD, Editor-in-Chief of The FASEB Journal, "but we still lack an adequate tissue model which can be used to test promising therapies and model deadly diseases. This advance, if it proves successful over time, will beat anything that's currently available."
About the Mount Sinai Health System The Mount Sinai Health System is an integrated health system committed to providing distinguished care, conducting transformative research, and advancing biomedical education. Structured around seven member hospital campuses and a single medical school, the Health System has an extensive ambulatory network and a range of inpatient and outpatient servicesfrom community-based facilities to tertiary and quaternary care.
Read the original here:
Engineered Cardiac Tissue Developed to Study the Human Heart
Chemical stem cell signature predicts treatment response for acute myeloid leukemia
By Sykes24Tracey
PUBLIC RELEASE DATE:
3-Feb-2014
Contact: Kim Newman sciencenews@einstein.yu.edu 718-430-3101 Albert Einstein College of Medicine
February 3, 2014 (Bronx, NY) Researchers at Albert Einstein College of Medicine of Yeshiva University and Montefiore Medical Center have found a chemical "signature" in blood-forming stem cells that predicts whether patients with acute myeloid leukemia (AML) will respond to chemotherapy.
The findings are based on data from nearly 700 AML patients. If validated in clinical trials, the signature would help physicians better identify which AML patients would benefit from chemotherapy and which patients have a prognosis so grave that they may be candidates for more aggressive treatments such as bone-marrow transplantation. The paper was published today in the online edition of the Journal of Clinical Investigation.
Sparing Patients from Debilitating Side Effects
According to the American Cancer Society, AML accounts for nearly one-third of all new leukemia cases each year. In 2013, more than 10,000 patients died of AML.
"AML is a disease in which fewer than 30 percent of patients are cured," said co-senior author Ulrich Steidl, M.D., Ph.D., associate professor of cell biology and of medicine and the Diane and Arthur B. Belfer Faculty Scholar in Cancer Research at Einstein and associate chair for translational research in oncology at Montefiore. "Ideally, we would like to increase that cure rate. But in the meantime, it would help if we could identify who won't benefit from standard treatment, so we can spare them the debilitating effects of chemotherapy and get them into clinical trials for experimental therapies that might be more effective."
Analyzing Methylation Patterns
The Einstein study focused on so-called epigenetic "marks" chemical changes in DNA that turn genes on or off. The researchers focused on one common epigenetic process known as methylation, in which methyl (CH3) groups attach in various patterns to the genes of human cells. Researchers have known that aberrations in the methylation of hematopoietic, or blood-forming, stem cells (HSCs) can prevent them from differentiating into mature blood cells, leading to AML.
See original here:
Chemical stem cell signature predicts treatment response for acute myeloid leukemia
A Little Acid Turns Mouse Blood Into Brain, Heart And Stem …
By Sykes24Tracey
The heart beats in a mouse embryo grown with stems cells made from blood.
Back in 1958, a young biologist at Cornell University made a stunning discovery.
He took a single cell from a carrot and then mixed it with some coconut milk. Days went by and the cell started dividing. Little roots formed. Stems started growing. Eventually, a whole new carrot plant rose up from the single cell.
Imagine if you could perform a similar feat with animal cells, even human cells.
A team of Japanese biologists say they've taken a big step toward doing just that, at least in mice. Instead of using coconut milk, though, the magic ingredient is something akin to lemon juice.
Biologist Haruko Obokata and her colleagues at the RIKEN Center for Developmental Biology say they've figured out a fast, easy way to make the most powerful cells in the world embryonic stem cells from just one blood cell.
The trick? Put white blood cells from a baby mouse in a mild acid solution, Obokata and her team report Wednesday in the journal Nature. Eventually a few stem cells emerge that can turn into any other cell in the body skin, heart, liver or neurons, you name it.
For decades, scientists have been searching for easy ways to make human embryonic stem cells. These cells hold great potential for treating diseases such as Alzheimer's, Parkinson's, heart disease and diabetes.
But for a long time, human stem cells were essentially off limits for researchers because the only way to get them was by destroying human embryos.
Then in 2007, another team of scientists at the RIKEN center figured out a way to make human stem cells from skin and blood by manipulating the cell's genes.
Follow this link:
A Little Acid Turns Mouse Blood Into Brain, Heart And Stem ...
Stem cell breakthrough: Scientists create embryonic-type …
By NEVAGiles23
MAURICIO LIMA/AFP/Getty Images
Scientists were able to reprogram mature stem cells to revert back to an embryonic state, a breakthrough that could make stem cell research easier and less expensive.
In experiments that could open a new era in stem cell biology, scientists have found a cheap and easy way to reprogram mature cells from mice back into an embryonic-like state that allowed them to generate many types of tissue.
The research, described as game-changing by experts in the field, suggests human cells could in future be reprogrammed by the same technique, offering a simpler way to replace damaged cells or grow new organs for sick and injured people.
Chris Mason, chair of regenerative medicine bioprocessing at University College London, who was not involved in the work, said its approach was "the most simple, lowest-cost and quickest method" to generate so-called pluripotent cells - able to develop into many different cell types - from mature cells.
RELATED: NEW YORK DOCS' 3D-PRINTED WINDPIPE REPRESENTS FUTURE OF TRANSPLANTS
"If it works in man, this could be the game changer that ultimately makes a wide range of cell therapies available using the patient's own cells as starting material - the age of personalized medicine would have finally arrived," he said.
The experiments, reported in two papers in the journal Nature on Wednesday, involved scientists from the RIKEN Center for Developmental Biology in Japan and Brigham and Women's Hospital and Harvard Medical School in the United States.
Beginning with mature, adult cells, researchers let them multiply and then subjected them to stress "almost to the point of death", they explained, by exposing them to various events including trauma, low oxygen levels and acidic environments.
RELATED: SCIENTISTS GROW TEETH USING STEM CELLS FROM URINE
See the rest here:
Stem cell breakthrough: Scientists create embryonic-type ...
Engineered cardiac tissue model developed to study human heart
By Sykes24Tracey
When it comes to finding cures for heart disease scientists are working to their own beat. That's because they may have finally developed a tissue model for the human heart that can bridge the gap between animal models and human patients. These models exist for other organs, but for the heart, this has been elusive. Specifically, the researchers generated the tissue from human embryonic stem cells with the resulting muscle having significant similarities to human heart muscle. This research was published in the February 2014 issue of The FASEB Journal.
"We hope that our human engineered cardiac tissues will serve as a platform for developing reliable models of the human heart for routine laboratory use," said Kevin D. Costa, Ph.D., a researcher involved in the work from the Cardiovascular Cell and Tissue Engineering Laboratory, Cardiovascular Research Center, Icahn School of Medicine at Mt. Sinai, in New York, NY. "This could help revolutionize cardiology research by improving the ability to efficiently discover, design, develop and deliver new therapies for the treatment of heart disease, and by providing more efficient screening tools to identify and prevent cardiac side effects, ultimately leading to safer and more effective treatments for patients suffering from heart disease."
To make this advance, Costa and colleagues cultured human engineered cardiac tissue, or hECTs, for 7-10 days and they self-assembled into a long thin heart muscle strip that pulled on the end-posts and caused them to bend with each heart beat, effectively exercising the tissue throughout the culture process. These hECTs displayed spontaneous contractile activity in a rhythmic pattern of 70 beats per minute on average, similar to the human heart. They also responded to electrical stimulation. During functional analysis, some of the responses known to occur in the natural adult human heart were also elicited in hECTs through electrical and pharmacological interventions, while some paradoxical responses of hECTs more closely mimicked the immature or newborn human heart. They also found that these human engineered heart tissues were able to incorporate new genetic information carried by adenovirus.
"We've come a long way in our understanding of the human heart," said Gerald Weissmann, M.D., Editor-in-Chief of The FASEB Journal, "but we still lack an adequate tissue model which can be used to test promising therapies and model deadly diseases. This advance, if it proves successful over time, will beat anything that's currently available."
Story Source:
The above story is based on materials provided by Federation of American Societies for Experimental Biology. Note: Materials may be edited for content and length.
Go here to see the original:
Engineered cardiac tissue model developed to study human heart
Scientists develop an engineered cardiac tissue model to study the human heart
By Dr. Matthew Watson
PUBLIC RELEASE DATE:
30-Jan-2014
Contact: Cody Mooneyhan cmooneyhan@faseb.org 301-634-7104 Federation of American Societies for Experimental Biology
When it comes to finding cures for heart disease scientists are working to their own beat. That's because they may have finally developed a tissue model for the human heart that can bridge the gap between animal models and human patients. These models exist for other organs, but for the heart, this has been elusive. Specifically, the researchers generated the tissue from human embryonic stem cells with the resulting muscle having significant similarities to human heart muscle. This research was published in the February 2014 issue of The FASEB Journal.
"We hope that our human engineered cardiac tissues will serve as a platform for developing reliable models of the human heart for routine laboratory use," said Kevin D. Costa, Ph.D., a researcher involved in the work from the Cardiovascular Cell and Tissue Engineering Laboratory, Cardiovascular Research Center, Icahn School of Medicine at Mt. Sinai, in New York, NY. "This could help revolutionize cardiology research by improving the ability to efficiently discover, design, develop and deliver new therapies for the treatment of heart disease, and by providing more efficient screening tools to identify and prevent cardiac side effects, ultimately leading to safer and more effective treatments for patients suffering from heart disease."
To make this advance, Costa and colleagues cultured human engineered cardiac tissue, or hECTs, for 7-10 days and they self-assembled into a long thin heart muscle strip that pulled on the end-posts and caused them to bend with each heart beat, effectively exercising the tissue throughout the culture process. These hECTs displayed spontaneous contractile activity in a rhythmic pattern of 70 beats per minute on average, similar to the human heart. They also responded to electrical stimulation. During functional analysis, some of the responses known to occur in the natural adult human heart were also elicited in hECTs through electrical and pharmacological interventions, while some paradoxical responses of hECTs more closely mimicked the immature or newborn human heart. They also found that these human engineered heart tissues were able to incorporate new genetic information carried by adenovirus.
"We've come a long way in our understanding of the human heart," said Gerald Weissmann, M.D., Editor-in-Chief of The FASEB Journal, "but we still lack an adequate tissue model which can be used to test promising therapies and model deadly diseases. This advance, if it proves successful over time, will beat anything that's currently available."
###
Receive monthly highlights from The FASEB Journal by e-mail. Sign up at http://www.faseb.org/fjupdate.aspx. The FASEB Journal is published by the Federation of the American Societies for Experimental Biology (FASEB). It is among the most cited biology journals worldwide according to the Institute for Scientific Information and has been recognized by the Special Libraries Association as one of the top 100 most influential biomedical journals of the past century.
FASEB is composed of 26 societies with more than 115,000 members, making it the largest coalition of biomedical research associations in the United States. Our mission is to advance health and welfare by promoting progress and education in biological and biomedical sciences through service to our member societies and collaborative advocacy.
Follow this link:
Scientists develop an engineered cardiac tissue model to study the human heart
Tiny machines that swim using heart muscle cells
By JoanneRUSSELL25
Scientists at the University of Illinois have created a minuscule swimming machine, just under eight-one-hundredth of an inch (1.95 mm), thats powered by beating heart muscle cells. Details of their invention, which might someday have medical applications for precision-targeting medication and micro-surgery inside the body, was published in the January 17, 2014 issue of the journal Nature Communications.
Professor Taher Saif, of the University of Illinois, leads the team that created what they call a tiny bio-hybrid machine or bio-bot. He said, in a press release:
Micro-organisms have a whole world that we only glimpse through the microscope. This is the first time that an engineered system has reached this underworld.
The bio-bot has a flagella-shaped body, that is, a cell with a long tail, like a sperm cell. The machine body is made from a flexible polymer thats coated with a substance called fibronectin, which provides an attachment surface for cardiac cells cultured on the bots head and tail. In a yet-to-be understood phenomenon, the heart cells communicate, align with each other, and synchronize their contraction-relaxation beat to move the machines tail. This motion creates waves in the fluid that propels the bot forward.
The scientists also created a faster-swimming bio-bot model with two tails. They think that a bio-bot with several tails could even be used to steer towards specific locations. This could give rise to tiny machine deployed to work on a microscopic scale. Saif commented:
The long-term vision is simple. Could we make elementary structures and seed them with stem cells that would differentiate into smart structures to deliver drugs, perform minimally invasive surgery or target cancer?
Bottom-line: University of Illinois scientists have created a microscopic swimming bio-bot thats powered by beating cardiac muscle cells. The tiny machine, measuring just under eight-one-hundredth of an inch (1.95 mm), may someday be adapted for medical applications inside the body. The journal Nature Communications published details of this research on January 17, 2014.
Follow this link:
Tiny machines that swim using heart muscle cells
Mayo wins FDA approval to test stem-cell technique for heart patients
By JoanneRUSSELL25
The Mayo Clinic in Rochester announced Friday that a decade-long research project on using stem cells to repair damaged heart tissue has won federal approval for human testing, a step that could have implications for millions of Americans with heart disease.
The U.S. Food and Drug Administration has approved a multistate clinical trial of 240 patients with chronic advanced symptomatic heart failure to determine if the procedure produces a significant improvement in heart function.
Safety testing in humans, completed earlier in Europe, showed a preliminary 25 percent improvement in cardiac outflow, according to Dr. Andre Terzic, director of the Mayo Clinic's Center for Regenerative Medicine.
The procedure could be a "paradigm shift" in the treatment of heart disease, Terzic said.
Treatments going forward won't just focus on easing the symptoms of the disease, Terzic said, but rather, on curing it.
The process, developed in collaborations with Cardio3 BioSciences of Belgium, involves harvesting stem cells from a heart patient's bone marrow in the hip, directing the cells to become "cardiopoietic" repair cells, then injecting them back into the heart to do their work.
Mayo researcher Dr. Atta Behfar and other members of Terzic's team isolated hundreds of proteins involved in the transcription process that takes place when stem cells are converted to heart cells. They identified eight proteins that were crucial in the development of heart cells and used them to convert stem cells into heart cells.
"This is unique in the world," Terzic said.
Forty hospitals in Europe and Israel are enrolling heart patients in human trials to test Mayo's new treatment regimen for heart failure. Enrollments are expected to be completed by the end of the year, and early results should be available in 2015, according to Dr. Christian Homsy, CEO of Cardio3 BioSciences.
If things go well, patients could start being treated with the new technology by the end of 2016 in Europe, and perhaps a year later in the United States.
See the original post here:
Mayo wins FDA approval to test stem-cell technique for heart patients
Stem Cells Might Reverse Heart Damage From Chemo – Cancer …
By LizaAVILA
By Jennifer Thomas HealthDay Reporter
WEDNESDAY, Dec. 30 (HealthDay News) -- Certain types of chemotherapy can damage the heart while thwarting cancer, a dilemma that has vexed scientists for years. But a new study in rats finds that injecting the heart with stem cells can reverse the damage caused by a potent anti-cancer drug.
The findings could one day mean that cancer patients could safely take higher doses of a powerful class of chemotherapy drugs and have any resulting damage to their hearts repaired later on using their own cardiac stem cells, the researchers said.
The study was published online Dec. 28 in advance of print publication in the journal Circulation.
Doxorubicin is a common chemotherapy drug used to treat many types of cancer, including breast, ovarian, lung, thyroid, neuroblastoma, lymphoma and leukemia.
But the drug can have serious side effects, including heart damage that can lead to congestive failure years after cancer treatment ends.
In the study, researchers removed cardiac stem cells from rodents before chemotherapy. The stem cells were isolated and expanded in the lab.
Rats were then given the chemo drug doxorubicin, inducing heart failure. Afterward, the rats' stem cells were re-injected into their hearts, and the damage was reversed.
"Theoretically, patients could be rescued using their own stem cells," said study author Dr. Piero Anversa, director of the Center for Regenerative Medicine at Brigham and Women's Hospital in Boston.
A Phase 1 clinical trial using a similar procedure in people is already under way, said Dr. Roberto Bolli, chief of cardiology and director of the Institute of Molecular Cardiology at the University of Louisville in Kentucky, who is heading the trial.
More:
Stem Cells Might Reverse Heart Damage From Chemo - Cancer ...
Stem cells tested to repair dead heart muscle
By Dr. Matthew Watson
(U-T San Diego) -- A new stem cell treatment may help heart attack patients do something once thought medically impossible regenerate dead heart muscle.
Scripps Health in La Jolla is one of three centers testing the therapy from Capricor, a Los Angeles biotech company. The cardiac stem cells are meant to boost the heart's natural ability to perform minor repairs. If it works, scars should shrink and functional heart muscle should grow.
Capricor gets the cells from donor hearts, grows them into the amount needed for treatment, then sends them to doctors taking part in what is called the Allstar trial. Doctors inject the cells into the coronary artery, where they are expected to migrate to the heart and encourage muscle regrowth.
The trial has successfully completed Phase 1, which mainly evaluates safety. On Dec. 17, Capricor said it had received permission to begin Phase 2, which will examine efficacy in about 300 patients who will get the treatment or a placebo. More information can be found at clinicaltrials.gov under the identifier NCT01458405.
The Allstar trial is funded with a $19.7 million "disease team" grant from the California Institute for Regenerative Medicine, or CIRM, the state's stem cell agency.
"This is a highly significant announcement for us at CIRM as it's the first time we've funded a therapy into a Phase 2 clinical trial, Chairman Jonathan Thomas said in a Dec. 23 statement.
About 600,000 Americans die of heart disease annually, making it the leading cause of death, according to the Centers for Disease Control and Prevention in Atlanta. Even those surviving may be left permanently impaired, if the heart is severely damaged. These are the patients Capricor seeks to help.
Mark Athens received Capricor's treatment on Sept. 25, about a month after having a moderate heart attack. The Encinitas resident was the last treated under Phase 1, said Scripps cardiologist Richard Schatz, who performed the procedure. It will take about six months to know whether the treatment worked, Schatz said.
Unlike many trials, Phase 1 was not placebo-controlled, so Athens knows he got the therapy. He appeared cheerful, smiling and bantering with his examining doctor during a Dec. 17 checkup at Scripps Green Hospital.
There's good reason to be optimistic about the treatment, Schatz said, because an earlier Capricor trial with a slightly different approach showed evidence of working.
Follow this link:
Stem cells tested to repair dead heart muscle
Stem Cell Therapy for Heart Disease Webchat – Dr. Ellis
By LizaAVILA
Monday, October 11, 2010 - Noon
Stephen Ellis, MD Section Head of Invasive/Interventional Cardiology, Robert and Suzanne Tomsich Department of Cardiovascular Medicine
Stem cells are natures own transformers. When the body is injured, stem cells travel to the scene of the accident and help heal damaged tissue. The cells do this by transforming into whatever type of cell has been injured- bone, skin and even heart tissue. Researchers at Cleveland Clinic believe that the efficiency of stem cells for treating heart tissue can be boosted and help the body recover faster and better from heart attacks. Join us in a free online chat with cardiologist Stephen Ellis, MD. Dr. Ellis is leading one of the clinical trials and will be answering your questions about stem cell therapy for heart disease.
Cleveland_Clinic_Host: Welcome to our "Stem Cell Therapy for Heart Disease" online health chat with Stephen Ellis, MD. Dr. Ellis is leading one of the research studies for stem cell therapy and heart disease so he will be answering a variety of questions on the topic. We are very excited to have him here today!
Thank for joining us Dr. Ellis, let's begin with the questions.
Dr__Ellis: Thank you for having me today.
Robert_B: I have a question on Stem Cell and stabilizing a two chamber heart condition.. Could donor adult stem cells help stabilize the heart and repair some of the damage? Patient also suffers from cardiac sclerosis of the liver.
Dr__Ellis: Stem cells are currently being evaluated to see if they may or may not strengthen hearts previously damaged by heart attacks or other conditions. They are considered experimental for this purpose. There are several ongoing clinical trials available in the U.S.
cabbagepatch: I have been going through other tests for heart transplant consideration, & with everything I have been going through would I be a candidate for heart stem cell repair? How would I find out? My cardiologist is Dr. Hsich in Cleveland.
Dr__Ellis: You may be a candidate for the NIH FOCUS trial at the Cleveland Clinic. Please ask Dr. Hsich - she would be able to help you.
Read more:
Stem Cell Therapy for Heart Disease Webchat - Dr. Ellis
Heart Stem Cell Therapy – – – University of Utah Health Care …
By JoanneRUSSELL25
Keeping in tradition with the Us commitment to advance the fields of medicine and surgery, our physicians are focusing on regenerative medicine as the next frontier in treating cardiovascular disease. Researchers within the Cardiovascular Center estimate cell therapy will be FDA-approved within three years. The goal of this therapy is to give cells back to the heart in order for it to grow stronger, work harder, and function more like a younger heart. Currently, studies include the potentiality of injecting cardiac repair cells into patients hearts to improve function.
This is the first trial of its kind in the United States, providing heart patients who have limited or no other options with a viable treatment. Using some of the best imaging technology, researchers have been able to see improvements in patients within six months after injecting their own cells directly into the left ventricle of the heart during minimally invasive surgery.
To contact us, please use the contact number provided.
The rest is here:
Heart Stem Cell Therapy - - - University of Utah Health Care ...
Groundbreaking Stem Cell Clinical Trial
By Sykes24Tracey
Florida Hospital Pepin Heart Institute is First in West & Central Florida to Perform a Groundbreaking Stem Cell Clinical Trial for Heart Failure Patients
The first patient has been treated as part of The ATHENA Trial, which derives stem cells from the patientsown adipose (fat) tissue and injects extracted cells into damaged parts of the heart.
TAMPA, Florida (December 20, 2013) Florida Hospital Pepin Heart Institute and Dr. Kiran C. Patel Research Institute announced the first patient, a 59 year old Clearwater man, has been treated as part of the ATHENA clinical trial. The trial, sponsored by San Diego-based Cytori Therapeutics, derives stem cells from the patients own fat tissue and injects extracted cells into damaged parts of the heart. The ATHENA trial is a treatment for chronic heart failure due to coronary heart disease. Dr. Charles Lambert, Medical Director of Florida Hospital Pepin Heart Institute, is leading the way for the first U.S. FDA approved clinical trial using adipose-derived regenerative cells, known as ADRCs, in chronic heart failure patients. I am pleased to report that all procedures went well. The patient is doing well, he was released and is recovering at home. We look forward to following his progress over the coming months, said Dr. Charles Lambert. Heart failure (HF) can occur when the muscles of the heart become weakened and cannot pump blood sufficiently throughout the body. The injury is most often caused by inadequate blood flow to the heart resulting from chronic or acute cardiovascular disease, including heart attacks. The ATHENA clinical trial procedure is a three step process. First, the trial involves the collection of fat from the patients body by liposuction. Then the fat sample is filtered through a machine that extracts out the stem cells. Finally, the stem cells are injected into the damaged part of the patients heart. During this first case at Florida Hospital Pepin Heart Institute, Dr. Paul Smith performed the liposuction to obtain the fat sample, a team at the Dr. Kiran C. Patel Research Institute isolated stem cells from the fat sample and then Dr. Charles Lambert performed the cell therapy by direct injection into the patients heart. Pepin Heart and Dr. Kiran C. Patel Research Institute is exploring and conducting leading-edge research to develop break-through treatments long before they are even available in other facilities. Stem cells have the unique ability to develop into many different cell types, and in many tissues serve as an internal repair system, dividing essentially without limit to replenish other cells, said Dr. Lambert.
The Pepin Heart Institute has a history of cardiovascular stem cell research as part of the NIH sponsored Cardiac Cell Therapy Research Network (CCTRN) as well as other active cell therapy trials. The trial is a double blind, randomized, placebo controlled study designed to study the use of a patients own Adipose-Derived Regenerative Cells (ADRCs) to treat chronic heart failure from coronary heart disease in patients who are on maximal therapy and still have heart failure symptoms. All trial participants undergo a minor liposuction procedure to remove fat (adipose) tissue. Following the liposuction, trial participants may have their tissue processed with Cytoris proprietary Celution System to separate and concentrate cells, and prepare them for therapeutic use. Trial participants will then have either their own cells or a placebo injected back into their damaged heart tissue. To test whether ADRCs will improve heart function, several measurements will be made, including peak oxygen consumption (VO2max), which measures how much physical exercise (gentle walking on a treadmill) a patient can perform, blood flow to the heart (perfusion), the amount of blood in the left ventricle at the end of contraction and relaxation (end-systolic and end-diastolic volumes), and the fraction of blood that is pumped during each contraction (ejection fraction). After the injection procedure, patients are seen in the clinic for follow-up visits over the first 12 months; they are then contacted by phone once a year for up to five years after the procedure.
There are approximately 5.1 million Americans currently living with heart failure, according to the American Heart Association. Chronic heart failure due to coronary heart disease is a severe, debilitating condition caused by restriction of blood flow to the heart muscle, reducing the hearts oxygen supply and limiting its pumping function. Individuals interested in participating in the ATHENA clinical research trial or learning more can visit http://www.theathenatrial.com or call Brian Nordgren, Florida Hospital Pepin Heart Institute Physician Assistant & Stem Cell Program Lead at (813) 615-7527.
About Florida Hospital Tampa Florida Hospital Tampa is a not-for-profit 475-bed tertiary hospital specializing in cardiovascular medicine, neuroscience, orthopaedics, womens services, pediatrics, oncology, endocrinology, bariatrics, wound healing, sleep medicine and general surgery including minimally invasive and robotic-assisted procedures. Also located at Florida Hospital Tampa is the renowned Florida Hospital Pepin Heart Institute, a recognized leader in cardiovascular disease prevention, diagnosis, treatment and leading-edge research. Part of the Adventist Health System, Florida Hospital is a leading health network comprised of 22 hospitals throughout the state. For more information, visit http://www.FHTampa.org.
About Florida Hospital Pepin Heart Institute and Dr. Kiran C. Patel Research Institute Florida Hospital Pepin Heart Institute is a free-standing cardiovascular institute providing comprehensive cardiovascular care with over 76,000 angioplasty procedures and 11,000 open-heart surgeries in the Tampa Bay region. Leading the way with the first accredited chest pain emergency room in Tampa Bay, the institute is among an elite few in the state of Florida chosen to perform the ground breaking Transcatheter Aortic Valve Replacement (TAVR) procedure. It is also a HeartCaring designated provider and a Larry King Cardiac Foundation Hospital. Florida Hospital Pepin Heart Institute and the Dr. Kiran C. Patel Research Institute, affiliated with the University of South Florida (USF), are exploring and conducting leading-edge research to develop break-through treatments long before they are available in most other hospitals. To learn more, visit http://www.FHPepin.org.
ends
Scoop Media
More here:
Groundbreaking Stem Cell Clinical Trial
Florida Hospital Pepin Heart Institute is First in West & Central Florida to Perform a Groundbreaking Stem Cell …
By raymumme
(PRWEB) December 20, 2013
Florida Hospital Pepin Heart Institute and Dr. Kiran C. Patel Research Institute announced the first patient, a 59 year old Clearwater man, has been treated as part of the ATHENA clinical trial. The trial, sponsored by San Diego-based Cytori Therapeutics, derives stem cells from the patients own fat tissue and injects extracted cells into damaged parts of the heart. The ATHENA trial is a treatment for chronic heart failure due to coronary heart disease. Dr. Charles Lambert, Medical Director of Florida Hospital Pepin Heart Institute, is leading the way for the first U.S. FDA approved clinical trial using adipose-derived regenerative cells, known as ADRCs, in chronic heart failure patients. I am pleased to report that all procedures went well. The patient is doing well, he was released and is recovering at home. We look forward to following his progress over the coming months, said Dr. Charles Lambert.
Heart failure (HF) can occur when the muscles of the heart become weakened and cannot pump blood sufficiently throughout the body. The injury is most often caused by inadequate blood flow to the heart resulting from chronic or acute cardiovascular disease, including heart attacks. The ATHENA clinical trial procedure is a three step process. First, the trial involves the collection of fat from the patients body by liposuction. Then the fat sample is filtered through a machine that extracts out the stem cells. Finally, the stem cells are injected into the damaged part of the patients heart. During this first case at Florida Hospital Pepin Heart Institute, Dr. Paul Smith performed the liposuction to obtain the fat sample, a team at the Dr. Kiran C. Patel Research Institute isolated stem cells from the fat sample and then Dr. Charles Lambert performed the cell therapy by direct injection into the patients heart. Pepin Heart and Dr. Kiran C. Patel Research Institute is exploring and conducting leading-edge research to develop break-through treatments long before they are even available in other facilities. Stem cells have the unique ability to develop into many different cell types, and in many tissues serve as an internal repair system, dividing essentially without limit to replenish other cells, said Dr. Lambert. The Pepin Heart Institute has a history of cardiovascular stem cell research as part of the NIH sponsored Cardiac Cell Therapy Research Network (CCTRN) as well as other active cell therapy trials. The trial is a double blind, randomized, placebo controlled study designed to study the use of a patients own Adipose-Derived Regenerative Cells (ADRCs) to treat chronic heart failure from coronary heart disease in patients who are on maximal therapy and still have heart failure symptoms. All trial participants undergo a minor liposuction procedure to remove fat (adipose) tissue. Following the liposuction, trial participants may have their tissue processed with Cytoris proprietary Celution System to separate and concentrate cells, and prepare them for therapeutic use. Trial participants will then have either their own cells or a placebo injected back into their damaged heart tissue. To test whether ADRCs will improve heart function, several measurements will be made, including peak oxygen consumption (VO2max), which measures how much physical exercise (gentle walking on a treadmill) a patient can perform, blood flow to the heart (perfusion), the amount of blood in the left ventricle at the end of contraction and relaxation (end-systolic and end-diastolic volumes), and the fraction of blood that is pumped during each contraction (ejection fraction). After the injection procedure, patients are seen in the clinic for follow-up visits over the first 12 months; they are then contacted by phone once a year for up to five years after the procedure. There are approximately 5.1 million Americans currently living with heart failure, according to the American Heart Association. Chronic heart failure due to coronary heart disease is a severe, debilitating condition caused by restriction of blood flow to the heart muscle, reducing the hearts oxygen supply and limiting its pumping function. Individuals interested in participating in the ATHENA clinical research trial or learning more can visit http://www.theathenatrial.com or call Brian Nordgren, Florida Hospital Pepin Heart Institute Physician Assistant & Stem Cell Program Lead at (813) 615-7527.
About Florida Hospital Pepin Heart Institute and Dr. Kiran C. Patel Research Institute Florida Hospital Pepin Heart Institute, located at Florida Hospital Tampa, is a free-standing cardiovascular institute providing comprehensive cardiovascular care with over 76,000 angioplasty procedures and 11,000 open-heart surgeries in the Tampa Bay region. Leading the way with the first accredited chest pain emergency room in Tampa Bay, the institute is among an elite few in the state of Florida chosen to perform the ground breaking Transcatheter Aortic Valve Replacement (TAVR) procedure. It is also a HeartCaring designated provider and a Larry King Cardiac Foundation Hospital. Florida Hospital Pepin Heart Institute and the Dr. Kiran C. Patel Research Institute, affiliated with the University of South Florida (USF), are exploring and conducting leading-edge research to develop break-through treatments long before they are available in most other hospitals. To learn more, visit http://www.FHPepin.org
About Cytori Therapeutics Cytori Therapeutics, Inc. is developing cell therapies based on autologous adipose-derived regenerative cells (ADRCs) to treat cardiovascular disease and repair soft tissue defects. Our scientific data suggest ADRCs improve blood flow, moderate the immune response and keep tissue at risk of dying alive. As a result, we believe these cells can be applied across multiple "ischemic" conditions. These therapies are made available to the physician and patient at the point-of-care by Cytori's proprietary technologies and products, including the Celution system product family. http://www.cytori.com
Original post:
Florida Hospital Pepin Heart Institute is First in West & Central Florida to Perform a Groundbreaking Stem Cell ...
Induced stem cells – Wikipedia, the free encyclopedia
By LizaAVILA
Induced stem cells (iSC) are stem cells artificially derived from some other (somatic, reproductive, pluripotent etc.) cell types by induced (i.e. initiated, forced) epigenetic reprogramming. In accordance to the developmental potentiality and the degree of cell dedifferentiation caused by induced reprogramming they are distinguished and subdivided as: induced totipotent, induced pluripotent stem cells (iPSc) and, obtained by so-called direct reprogramming or directed forced differentiation, induced progenitor (multipotent or unipotent) stem cells, also called induced somatic stem cells. Currently, there are three ways to reprogram somatic cells into stem cells[1] These are:
The reversible transformation of one differentiated cell type to another type of mature differentiated cells is called metaplasia.[22] This transition from one cell type to another can be a part of the normal maturation process, or caused by some of its inducing stimulus. For example: transformation of cells of the iris to the lens in the process of maturation and transformation of the retinal pigment epithelium cells into the neural retina during regeneration in adult newt eyes. This process allows the body to replace the original cells not suitable to new conditions, into new cells which are more suited to new conditions. In experiments on cells in Drosophila imaginal discs, it was found that there are a limited number of standard discrete states of differentiation and the cells have to choose one of them. The fact that transdetermination (change of the path of differentiation) often take place not in one, but in a group of cells shows that it is not caused by a mutation but is induced.[23][24]
Some types of mature, specialized adult cells can naturally revert to stem cells. For example, differentiated cells, which are called chief cells and express the stem cell marker Troy, normally produce digestive fluids for the stomach, yet they can change back into stem cells to make temporary repairs in significant stomach injuries, such as a cut or damage from infection. Moreover theyre making this transition even in the absence of noticeable injuries and are capable of replenishing entire gastric units, essentially serving as quiescent reserve stem cells.[25] Differentiated airway epithelial cells can revert into stable and functional stem cells in vivo.[26] After injury, mature terminally differentiated kidney cells dedifferentiate into more primordial versions of themselves, and then differentiate into the cell types needing replacement in the damaged tissue[27] Macrophages can self-renew by local proliferation of mature differentiated cells.[28] In Newts, muscle tissue is regenerated from specialized muscle cells that dedifferentiate and forget what type of cell they've been. This capacity to regenerate tissue does not decline with age, which may be linked to their ability to make new stem cells from muscle cells on demand.[29]
It should be noted that there are also a variety of nontumorigenic stem cells with the ability to generate the multiple cell types. For instance, multilineage-differentiating stress-enduring (Muse) cells are the stress-tolerant adult human stem cells that can self-renew; form characteristic cell clusters in suspension culture that express a set of genes associated with pluripotency; and can differentiate into endodermal, ectodermal, and mesodermal cells both in vitro and in vivo.[30][31][32][33]
Detailed description of some other well-documented examples of transdifferentiation, and their significance in development and regeneration are reviewed in.[34]
Induced totipotent cells usually can be obtained by reprogramming somatic cells by somatic-cell nuclear transfer (SCNT) to the recipient eggs or oocytes.[3][5][35][36][37] Sometimes may be used the oocytes of other species, such as sheep.[38] New possibilities for creating genetically modified animals opens method of induced androgenetic haploid embryonic stem cells, which can be used instead of sperm. These cells, synchronized in M phase and injected into the oocyte allow to get viable offspring.[39] These developments, together with data on the possibility to obtain unlimited number of oocytes from mitotically active reproductive stem cells[40] offer the possibility of industrial production of transgenic farm animals. Repeated recloning of viable mice through a somatic cell nuclear transfer method that includes a histone deacetylase inhibitor trichostatin, added to the cell culture medium,[41] show that it may be possible to reclone animals indefinitely without any visible accumulation of reprogramming or genomic errors [42] However, research into technologies to develop sperm and egg cells from stem cells bring up bioethical issues.
Such technologies may also have far-reaching clinical applications for overcoming cytoplasmic defects in human oocytes.[43][44][45] For example, the technology have been developed that could prevent inherited mitochondrial disease being passed on to the next generation. Mitochondria, often described as the powerhouse of the cell, contain genetic material, which is passed from mother to child. Mutations on mitochondrial DNA can cause diabetes, deafness, eye disorders, gastrointestinal disorders, heart disease, dementia and several other neurological diseases. The nucleus from one human egg cell have been transferred to another egg, effectively swapping the cell cytoplasm, which includes the mitochondria (and their DNA), creating a cell that could be regarded as having two mothers. The eggs were then fertilised, and the resulting embryonic stem cells carried the swapped mitochondrial DNA.[46]
Read more about the latest achievements of the cloning techniques and the generation of totipotent cells, in:[47]
See also main article: induced pluripotent stem cells (iPSc)
First iPSc were obtained in the form of transplantable teratocarcinoma induced by the graft taken from mouse embryos.[48] It was shown that teratocarcinoma formed from somatic cells.[49] The fact that normal genetically mosaic mice can be obtained from malignant teratocarcinoma cells confirmed their pluripotency.[50][51][52] It turned out that teratocarcinoma cells are able to maintain a culture of pluripotent embryonic stem cells in an undifferentiated state, by supplying the culture medium with various factors.[53] Thus, as early as in the 1980s, it became clear that the transplantation of pluripotent or embryonic stem cells into the body of adult mammals, usually leads to the formation of teratomas, which can then turn into a malignant tumor teratocarcinoma.[54] If, however, to put the teratocarcinoma cells into the early mammal embryo (at the blastocyst stage), they became incorporated in the cell mass of blastocysts and from such a chimeric (i.e. composed of cells from different organisms) blastocyst often develops normal chimeric animal.[55][56][57] This indicated that the cause of the teratoma is a dissonance - mutual misunderstanding of "speech" of young donor cells and surrounding adult cells (so-called niche) of the recipient.
Here is the original post:
Induced stem cells - Wikipedia, the free encyclopedia