Public release date: 26-Feb-2012
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Contact: Sue McGreevey
smcgreevey@partners.org
617-724-2764
Massachusetts General Hospital

For the first time, Massachusetts General Hospital (MGH) researchers have isolated egg-producing stem cells from the ovaries of reproductive age women and shown these cells can produce what appear to be normal egg cells or oocytes. In the March issue of Nature Medicine, the team from the Vincent Center for Reproductive Biology at MGH reports the latest follow-up study to their now-landmark 2004 Nature paper that first suggested female mammals continue producing egg cells into adulthood.

"The primary objective of the current study was to prove that oocyte-producing stem cells do in fact exist in the ovaries of women during reproductive life, which we feel this study demonstrates very clearly," says Jonathan Tilly, PhD, director of the Vincent Center for Reproductive Biology in the MGH Vincent Department of Obstetrics and Gynecology, who led the study. "The discovery of oocyte precursor cells in adult human ovaries, coupled with the fact that these cells share the same characteristic features of their mouse counterparts that produce fully functional eggs, opens the door for development of unprecedented technologies to overcome infertility in women and perhaps even delay the timing of ovarian failure."

The 2004 report from Tilly's team challenged the fundamental belief, held since the 1950s, that female mammals are born with a finite supply of eggs that is depleted throughout life and exhausted at menopause. That paper and a 2005 follow-up published in Cell showing that bone marrow or blood cell transplants could restore oocyte production in adult female mice after fertility-destroying chemotherapy were controversial; but in the intervening years, several studies from the MGH-Vincent group and other researchers around the world have supported Tilly's work and conclusions.

These supporting studies include a 2007 Journal of Clinical Oncology report from the MGH-Vincent team that showed female mice receiving bone marrow transplants after oocyte-destroying chemotherapy were able to have successful pregnancies, delivering pups that were their genetic offspring and not of the marrow donors. A 2009 study from a team at Shanghai Jiao Tong University in China, published in Nature Cell Biology, not only isolated and cultured oocyte-producing stem cells (OSCs) from adult mice but also showed that those OSCs, after transplantation into the ovaries of chemotherapy-treated female mice, gave rise to mature oocytes that were ovulated, fertilized and developed into healthy offspring.

"That study singlehandedly deflated many of the arguments from critics of our earlier Nature paper by showing that oocyte-producing stem cells exist in mice and could develop into fully functional eggs," says Tilly. Another paper from a west-coast biotechnology company, published in Differentiation in 2010, provided further independent confirmation of Tilly's earlier conclusions regarding the presence of oocyte-producing stem cells in ovaries of adult mice.

Tilly is quick to point out, however, "These follow-up studies, while providing definitive evidence that oocyte-producing stem cells exist in ovaries of adult female mammals, were not without their limitations, leaving the question open in some scientific circles of whether the adult oocyte pool can be renewed. For example, the protocol used to isolate OSCs in the 2009 Nature Cell Biology study is a relatively crude approach that often results in the contamination of desired cells by other cell types." To address this, the MGH-Vincent team developed and validated a much more precise cell-sorting technique to isolate OSCs without contamination from other cells.

The 2009 study from China also had isolated OSCs based on cell-surface expression of a marker protein called Ddx4 or Mvh, which previously had been found only in the cytoplasm of oocytes. This apparent contradiction with earlier studies raised concerns over the validity of the protocol. Using their state-of-the-art fluorescence-activated cell sorting techniques, the MGH-Vincent team verified that, while the marker protein Ddx4 was indeed located inside oocytes, it was expressed on the surface of a rare and distinct population of ovarian cells identified by numerous genetic markers and functional tests as OSCs.

To examine the functional capabilities of the cells isolated with their new protocol, the investigators injected green fluorescent protein (GFP)-labeled mouse OSCs into the ovaries of normal adult mice. Several months later, examination of the recipient mouse ovaries revealed follicles containing oocytes with and without the marker protein. GFP-labeled and unlabeled oocytes also were found in cell clusters flushed from the animals' oviducts after induced ovulation. The GFP-labeled mouse eggs retrieved from the oviducts were successfully fertilized in vitro and produced embryos that progressed to the hatching blastocyst stage, a sign of normal developmental potential. Additionally, although the Chinese team had transplanted OSCs into ovaries of mice previously treated with chemotherapy, the MGH-Vincent team showed that it was not necessary to damage the recipient mouse ovaries with toxic drugs before introducing OSCs.

In their last two experiments, which Tilly considers to be the most groundbreaking, the MGH-Vincent team used their new cell-sorting techniques to isolate potential OSCs from adult human ovaries. The cells obtained shared all of the genetic and growth properties of the equivalent cells isolated from adult mouse ovaries, and like mouse OSCs, were able to spontaneously form cells with characteristic features of oocytes. Not only did these oocytes formed in culture dishes have the physical appearance and gene expression patterns of oocytes seen in human ovaries ? as was the case in parallel mouse experiments ? but some of these in-vitro-formed cells had only half of the genetic material normally found in all other cells of the body. That observation indicates that these oocytes had progressed through meiosis, a cell-division process unique to the formation of mature eggs and sperm.

The researchers next injected GFP-labeled human OSCs into biopsied human ovarian tissue that was then grafted beneath the skin of immune-system-deficient mice. Examination of the human tissue grafts 7 to 14 days later revealed immature human follicles with GFP-negative oocytes, probably present in the human tissue before OSC injection and grafting, as well as numerous immature human follicles with GFP-positive oocytes that would have originated from the injected human OSCs.

"These experiments provide pivotal proof-of-concept that human OSCs reintroduced into adult human ovarian tissue performed their expected function of generating new oocytes that become enclosed by host cells to form new follicles," says Tilly, a professor of Obstetrics, Gynecology and Reproductive Biology at Harvard Medical School and chief of Research at the MGH Vincent Department of Obstetrics and Gynecology. "These outcomes are exactly what we see if we perform the same experiments using GFP-expressing mouse OSCs, and GFP-expressing mouse oocytes formed that way go on to develop into fully functional eggs.

"In this paper we provide the three key pieces of evidence requested by those who have been skeptical of our previous work," he adds. "We developed and extensively validated a cell-sorting protocol to reliably purify OSCs from adult mammalian ovaries, proving once again that these very special cells exist. We tested the function of mouse oocytes produced by these OSCs and showed that they can be fertilized to produce healthy embryos. And we identified and characterized an equivalent population of oocyte-producing stem cells isolated from adult human ovaries."

Among the many potential clinical applications for these findings that Tilly's team is currently exploring are the establishment of human OSC banks ? since these cells, unlike human oocytes, can be frozen and thawed without damage ? the identification of hormones and factors that accelerate the formation of oocytes from human OSCs, the development of mature human oocytes from OSCs for in vitro fertilization, and other approaches to improve the outcomes of IVF and other infertility treatments.

###

Tilly notes that an essential part of his group's accomplishment was collaboration with study co-author Yasushi Takai, MD, PhD, a former MGH research fellow on Tilly's team and now a faculty member at Saitama Medical University in Japan. Working with his clinical colleagues at Saitama, Takai was able to provide healthy ovarian tissue from consenting patients undergoing sex reassignment surgery, many in their 20s and early 30s. Co-lead authors of the Nature Medicine report are Yvonne White, PhD, and Dori Woods, PhD, of the Vincent Center for Reproductive Biology at MGH. Additional co-authors are Osamu Ishihara, MD, PhD, and Hiroyuki Seki, MD, PhD, of Saitama Medical University.

The study was supported by a 10-year MERIT Award to Tilly from the National Institute on Aging, a Ruth L. Kirschstein National Research Service Award from the National Institutes of Health, the Henry and Vivian Rosenberg Philanthropic Fund, the Sea Breeze Foundation, and Vincent Memorial Hospital Research Funds. Tilly is a co-founder of OvaScience, Inc. (www.ovascience.com), which has licensed the commercial potential of these and other patent-protected findings of the MGH-Vincent team for development of new fertility-enhancing procedures.

Massachusetts General Hospital (www.massgeneral.org), founded in 1811, is the original and largest teaching hospital of Harvard Medical School. The MGH conducts the largest hospital-based research program in the United States, with an annual research budget of more than $750 million and major research centers in AIDS, cardiovascular research, cancer, computational and integrative biology, cutaneous biology, human genetics, medical imaging, neurodegenerative disorders, regenerative medicine, reproductive biology, systems biology, transplantation biology and photomedicine.

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Continue reading here:
Mass. General researchers isolate egg-producing stem cells from adult human ovaries

27 February 2012 Last updated at 00:06 ET

Hydrogen sulphide, the gas famed for generating the stench in stink bombs, flatulence and bad breath, has been harnessed by stem cell researchers in Japan.

Their study, in the Journal of Breath Research, investigated using it to help convert stem cells from human teeth into liver cells.

The scientists claimed the gas increased the purity of the stem cells.

Small amounts of hydrogen sulphide are made by the body.

It is also produced by bacteria and is toxic in large quantities.

Therapy

A group in China has already reported using the gas to enhance the survival of mesenchymal stem cells taken from the bone marrow of rats.

Researchers at the Nippon Dental University were investigating stem cells from dental pulp - the bit in the middle of the tooth.

They said using the gas increased the proportion of stem cells which were converted to liver cells when used alongside other chemicals. The idea is that liver cells produced from stem cells could be used to repair the organ if it was damaged.

Dr Ken Yaegaki, from Nippon Dental University in Japan, said: "High purity means there are less 'wrong cells' that are being differentiated to other tissues, or remaining as stem cells."

One of the concerns with dental pulp as a source of stem cells is the number that can be harvested.

However, the study did not say how many cells were actually produced.

Prof Chris Mason, a specialist in regenerative medicine at University College London, said: "It would be interesting to see how hydrogen sulphide works with other cells types."

See more here:
Bad breath used as stem cell tool

Public release date: 26-Feb-2012
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Contact: Joe Winters
joseph.winters@iop.org
44-794-632-1473
Institute of Physics

Japanese scientists have found that the odorous compound responsible for halitosis ? otherwise known as bad breath ? is ideal for harvesting stem cells taken from human dental pulp.

In a study published today, Monday 27 February, in IOP Publishing's Journal of Breath Research, researchers showed that hydrogen sulphide (H2S) increased the ability of adult stem cells to differentiate into hepatic (liver) cells, furthering their reputation as a reliable source for future liver-cell therapy.

This is the first time that liver cells have been produced from human dental pulp and, even more impressively, have been produced in high numbers of high purity.

"High purity means there are less 'wrong cells' that are being differentiated to other tissues, or remaining as stem cells. Moreover, these facts suggest that patients undergoing transplantation with the hepatic cells may have almost no possibility of developing teratomas or cancers, as can be the case when using bone marrow stem cells," said lead author of the study Dr. Ken Yaegaki.

The remarkable transforming ability of stem cells has led to significant focus from research groups around the world and given rise to expectations of cures for numerable diseases, including Parkinson's and Alzheimer's.

In this study, Dr. Ken Yaegaki and his group, from Nippon Dental University, Japan, used stem cells from dental pulp ? the central part of the tooth made up of connective tissue and cells ? which were obtained from the teeth of dental patients who were undergoing routine tooth extractions.

Once the cells were sufficiently prepared, they were separated into two batches (a test and a control) and the test cells incubated in a H2S chamber. They were harvested and analysed after 3, 6 and 9 days to see if the cells had successfully transformed into liver cells.

To test if the cells successfully differentiated under the influence of H2S, the researchers carried out a series of tests looking at features that were characteristic of liver cells. In addition to physical observations under the microscope, the researchers investigated the cell's ability to store glycogen and then recorded the amount of urea contained in the cell.

"Until now, nobody has produced the protocol to regenerate such a huge number of hepatic cells for human transplantation. Compared to the traditional method of using fetal bovine serum to produce the cells, our method is productive and, most importantly, safe" continued Dr. Yaegaki.

Hydrogen sulphide (H2S) has the characteristic smell of rotten eggs and is produced throughout the body in the tissues. Although its exact function is unknown, researchers have been led to believe that it plays a key role in many physiological processes and disease states.

###

From Monday 27 February, this paper can be downloaded from http://iopscience.org/1752-7163/6/1/017103

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Go here to read the rest:
Dental pulp stem cells transformed by 'bad breath' chemical

Washington, Feb 27 (ANI): The odorous compound responsible for halitosis - otherwise known as bad breath - may play a key role in harvesting stem cells taken from human dental pulp, a new study has suggested.

In the study, Japanese scientists showed that hydrogen sulphide (H2S) increased the ability of adult stem cells to differentiate into hepatic (liver) cells, furthering their reputation as a reliable source for future liver-cell therapy.

This is the first time that liver cells have been produced from human dental pulp and, even more impressively, have been produced in high numbers of high purity.

"High purity means there are less 'wrong cells' that are being differentiated to other tissues, or remaining as stem cells. Moreover, these facts suggest that patients undergoing transplantation with the hepatic cells may have almost no possibility of developing teratomas or cancers, as can be the case when using bone marrow stem cells," said lead author of the study Dr. Ken Yaegaki.

The remarkable transforming ability of stem cells has led to significant focus from research groups around the world and given rise to expectations of cures for numerable diseases, including Parkinson's and Alzheimer's.

In this study, Dr. Yaegaki and his group, from Nippon Dental University, Japan, used stem cells from dental pulp - the central part of the tooth made up of connective tissue and cells - which were obtained from the teeth of dental patients who were undergoing routine tooth extractions.

Once the cells were sufficiently prepared, they were separated into two batches (a test and a control) and the test cells incubated in a H2S chamber.

They were harvested and analysed after 3, 6 and 9 days to see if the cells had successfully transformed into liver cells.

To test if the cells successfully differentiated under the influence of H2S, the researchers carried out a series of tests looking at features that were characteristic of liver cells.

In addition to physical observations under the microscope, the researchers investigated the cell's ability to store glycogen and then recorded the amount of urea contained in the cell.

"Until now, nobody has produced the protocol to regenerate such a huge number of hepatic cells for human transplantation. Compared to the traditional method of using fetal bovine serum to produce the cells, our method is productive and, most importantly, safe," Dr. Yaegaki added.

Hydrogen sulphide (H2S) has the characteristic smell of rotten eggs and is produced throughout the body in the tissues.

Although its exact function is unknown, researchers have been led to believe that it plays a key role in many physiological processes and disease states.

The study has been published in IOP Publishing's Journal of Breath Research. (ANI)

Originally posted here:
'Bad breath' chemical may fuel development of dental pulp stem cells

For 60 years, doctors have thought women were born with all the eggs they’ll ever have. Now Harvard scientists are challenging that belief, saying they’ve discovered the ovaries of young women harbor very rare stem cells capable of producing new eggs.

If Sunday’s report is confirmed, harnessing those stem cells might one day lead to better treatments for women left infertile because of disease - or simply because they’re getting older.

“Our current views of ovarian aging are incomplete. There’s much more to the story than simply the trickling away of a fixed pool of eggs,” said lead researcher Jonathan Tilly of Harvard’s Massachusetts General Hospital, who has long hunted these cells in a series of controversial studies.

Mr. Tilly’s previous work drew fierce skepticism, and independent experts urged caution about the latest findings.

A key next step is to see whether other laboratories can verify the work. If so, then it would take years of additional research to learn how to use the cells, said Teresa Woodruff, fertility preservation chief at Northwestern University’s Feinberg School of Medicine.

Still, even a leading critic said such research may help dispel some of the enduring mystery surrounding how human eggs are born and mature.

“This is going to spark renewed interest, and more than anything else it’s giving us some new directions to work in,” said David Albertini, director of the University of Kansas' Center for Reproductive Sciences. While he has plenty of questions about the latest work, “I’m less skeptical,” he said.

Scientists have long taught that all female mammals are born with a finite supply of egg cells, called ooctyes, that runs out in middle age. Mr. Tilly, Mass General’s reproductive biology director, first challenged that notion in 2004, reporting that the ovaries of adult mice harbor some egg-producing stem cells. Recently, Mr. Tilly noted, a lab in China and another in the U.S. also have reported finding those rare cells in mice.

But do they exist in women? Enter the new work, reported Sunday in the journal Nature Medicine.

Mr. Tilly collaborated with scientists at Japan’s Saitama Medical University who were freezing ovaries donated for research by healthy 20-somethings who underwent a sex-change operation.

Mr. Tilly also had to address a criticism: how to tell if he was finding true stem cells or just very immature eggs. His team latched onto a protein believed to sit on the surface of only those purported stem cells and fished them out. To track what happened next, the researchers inserted a gene that makes some jellyfish glow green into those cells. If the cells made eggs, those would glow, too.

“Bang, it worked - cells popped right out” of the human tissue, Mr. Tilly said.

Researchers watched through a microscope as new eggs grew in a lab dish. Then came the pivotal experiment: They injected the stem cells into pieces of human ovary and transplanted the human tissue under the skin of mice. Within two weeks, they reported telltale green-tinged egg cells forming.

More work also is needed to tell exactly what these cells are and whether they’ll mature in usable eggs, cautioned reproductive biologist Kyle Orwig of the University of Pittsburgh Medical Center, who has watched Mr. Tilly’s work with great interest.

But if they’re really competent stem cells, Mr. Orwig asked, then why would women undergo menopause? Indeed, something so rare wouldn’t contribute much to a woman’s natural reproductive capacity, added Northwestern’s Ms. Woodruff.

Copyright 2012 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

Excerpt from:
Report says women have egg-producing stem cells

1:00 AM
If confirmed, harnessing such cells may lead to better treatments for women left infertile by disease or age.

The Associated Press

WASHINGTON - For 60 years, doctors have believed that women were born with all the eggs they'll ever have. Now Harvard scientists say they've found that the ovaries of young women harbor rare stem cells capable of producing new eggs.

FOR MORE

READ A SUMMARY of the report on how women's stem cells can be turned into eggs: tinyurl.com/6w6kass

If Sunday's report is confirmed, harnessing those stem cells might one day lead to better treatments for women left infertile because of disease -- or simply because they're getting older.

"Our current views of ovarian aging are incomplete. There's much more to the story than simply the trickling away of a fixed pool of eggs," said lead researcher Jonathan Tilly of Harvard's Massachusetts General Hospital, who has long hunted these cells in a series of controversial studies.

A next step is to see whether other laboratories can verify the work. If so, then it would take years of further study to learn how to use the cells, said Teresa Woodruff, fertility preservation chief at Northwestern University's Feinberg School of Medicine.

Still, even a leading critic said such research may help dispel some of the enduring mystery surrounding how human eggs are born and mature.

"More than anything else, it's giving us some new directions to work in," said David Albertini, director of the University of Kansas' Center for Reproductive Sciences.

Scientists have long taught that all female mammals are born with a finite supply of egg cells, called ooctyes, that runs out in middle age. Tilly first challenged that notion in 2004, reporting that the ovaries of adult mice harbor some egg-producing stem cells.

But do they exist in women? Enter the new work, reported Sunday in the journal Nature Medicine.

Tilly collaborated with scientists at Japan's Saitama Medical University, who were freezing ovaries donated for study by healthy 20-somethings who underwent sex-change operations.

He had to figure out how to tell if he was finding true stem cells or just very immature eggs.

His team latched on to a protein believed to sit on the surface of only those purported stem cells and fished them out. To track what happened next, the researchers inserted a gene that makes some jellyfish glow green into those cells. If the cells made eggs, those would glow, too.

"Bang, it worked -- cells popped right out" of the human tissue, Tilly said.

Researchers watched through a microscope as new eggs grew in a lab dish. Then came the pivotal experiment: They injected the stem cells into pieces of human ovary. They transplanted the human tissue under the skin of mice, to provide it a nourishing blood supply. Within two weeks, they reported telltale green-tinged egg cells forming.

Read more:
Rare stem cells may produce new eggs, scientists say

In research that could have far-reaching implications for female fertility, U.S. scientists have isolated stem cells from human ovarian tissue that give rise to what appear to be normal egg cells.

The finding, published Sunday in the journal Nature Medicine, builds on earlier landmark papers by the Boston researchers, which suggest that female mammals continue producing egg cells, known as oocytes, into adulthood.

Since 2004, the scientists at Massachusetts General Hospital have produced a series of papers based on work in laboratory mice, which challenge the long-held belief that female mammals are born with a finite number of eggs that run out at a certain point in the life cycle.

The team was able to isolate stem cells from ovarian tissue taken from mice, from which they grew fully functional egg cells in the lab, which could then be fertilized and even produce healthy offspring.

"The primary objective of the current study was to prove that oocyte-producing stem cells do, in fact, exist in the ovaries of women during reproductive life, which we feel this study demonstrates very clearly," said lead author Jonathan Tilly, director of the Vincent Center for Reproductive Biology at Massachusetts General.

In their experiments, the team isolated the stem cells from ovarian tissue that had been removed from women in their 20s and early 30s.

When put in culture dishes in the lab, these stem cells gave rise to cells with the characteristic features of oocytes, including the physical appearance and gene expression patterns of those seen inside human ovaries.

"They spontaneously generate eggs in the dish," Tilly said in a phone interview, noting that they proliferate so well that a small number of stem cells could easily spawn a million egg cells in the lab.

The researchers next took stem cells they had genetically manipulated to glow green and injected them into snippets of human ovarian tissue. These prepared tissue bits were then grafted beneath the skin of specially bred mice, which have no immune system that can cause rejection of human tissue.

Within two weeks, researchers discovered the implanted ovarian tissue in the mice contained numerous immature human follicles with egg cells that originated from the injected stem cells. Follicles are small sacs within the ovary which contain maturing eggs.

Tilly said they knew the eggs cells had arisen from the injected stem cells "because they were all green."

Among the many potential clinical applications the researchers are exploring is whether these stem cells could produce oocytes that could play a role in in-vitro fertilization, as well as other applications to improve the outcomes of IVF and other infertility treatments.

"Can we use these cells for fertility reasons to maximize the opportunity for patients who are experiencing infertility to have different options available to them to have a genetically matched child?" asked Tilly.

"I think it's a fairly good possibility that at some point in the not-too-distant future there will be clinical protocols developed using some aspect of these cells or their properties that will have a significant impact on human reproduction."

Among them is the idea of extracting structures responsible for energy production in cells — called mitochondria — from the stem cells and injecting them into a woman's eggs at the time of in-vitro fertilization, with the hope of boosting the chances of conception and a successful birth.

But Tilly said another idea is to see whether these ovarian stem cells could be used to delay menopause — and the myriad health effects that can develop as women age.

"I've always been intrigued by the prospects of what if you could slow the rate at which the egg cell pool goes away and end up keeping an ovary functioning long past its normal time of failure," he said.

"With these egg stem cells, it raises the prospect that by harnessing the power of those cells, perhaps we can control the rate at which that precious reserve of egg cells is depleted and maybe even delay it ... And if you could achieve that, what would happen? Would we truly see a benefit or would there be unforeseen bad effects?"

More than a decade ago, Tilly's lab created a mouse through genetic manipulation that did not experience ovarian failure with age and was able to maintain an adequate reservoir of eggs.

"So it didn't undergo the equivalent of menopause," he said, or "mouseopause" as the scientists have dubbed it.

While normal mice as they reach old age experience health problems similar to those of postmenopausal women — including declining eyesight and hearing, hair loss, osteoporosis, diminished cognitive function and reduced muscle mass — these genetically modified mice did not. Nor did they have an increased risk of cancer.

So could these stem cells one day be used as the basis for an anti-aging treatment?

"There would be some pretty significant health benefits that would come out of it," said Tilly, if that were the case.

Even though every aspect of the human oocyte-producing stem cells have so far matched what the researchers have found in their mouse equivalents, Tilly conceded that "mouse is mouse — and perhaps human will be different."

"We don't know" if eggs generated from human ovarian stem cells will be normal and healthy, he said. "We will have to be very careful if and when we get to that stage."

Go here to read the rest:
Human ovarian stem cells may hold promise for treating infertility: study

Researchers have found that it is possible for stem cells in adult women to produce human eggs in the laboratory, according to the BBC.

The study, published in the journal Nature Medicine, said further experiments on mice showed that eggs derived in such a manner can be fertilized, potentially opening the door for creating an unlimited supply of eggs in order to treat infertility.

Bloomberg reported that the research was conducted by a team led by Jonathan Tilly, the director of Massachusetts General Hospital’s Vincent Center for Reproductive Biology, which is affiliated with Harvard University.

The research builds on a discovery in 2004, in which Tilly found that ovarian stem cells in mice could create new eggs, said Bloomberg. The study’s findings challenge the belief that a woman’s ovaries can’t make any more eggs after menopause.

More on GlobalPost: Stem cells used to heal heart attack damage

The New York Times said the research used a cell-sorting machine to target a special protein that marks the surface of reproductive cells. Using those cells, the team was able to generate eggs that could potentially be fertilized and then produce embryos.

Dr. Tilly said, "The discovery of oocyte precursor cells in adult human ovaries, coupled with the fact that these cells share the same characteristic features of their mouse counterparts that produce fully functional eggs, opens the door for development of unprecedented technologies to overcome infertility in women and perhaps even delay the timing of ovarian failure."

More on GlobalPost: Scientists create brain cells from human skin in possible breakthrough for autism, Alzheimer's research

Below is the video from Nature Medicine explaining more about the procedure:

http://www.globalpost.com/dispatch/news/health/120226/researchers-used-stem-cells-produce-human-eggs

Originally posted here:
Researchers used stem cells to produce human eggs

WASHINGTON (AP) — For 60 years, doctors have believed women were born with all the eggs they'll ever have. Now Harvard scientists are challenging that dogma, saying they've discovered the ovaries of young women harbor very rare stem cells capable of producing new eggs.

If Sunday's report is confirmed, harnessing those stem cells might one day lead to better treatments for women left infertile because of disease — or simply because they're getting older.

"Our current views of ovarian aging are incomplete. There's much more to the story than simply the trickling away of a fixed pool of eggs," said lead researcher Jonathan Tilly of Harvard's Massachusetts General Hospital, who has long hunted these cells in a series of controversial studies.

Tilly's previous work drew fierce skepticism, and independent experts urged caution about the latest findings.

A key next step is to see whether other laboratories can verify the work. If so, then it would take years of additional research to learn how to use the cells, said Teresa Woodruff, fertility preservation chief at Northwestern University's Feinberg School of Medicine.

Still, even a leading critic said such research may help dispel some of the enduring mystery surrounding how human eggs are born and mature.

"This is going to spark renewed interest, and more than anything else it's giving us some new directions to work in," said David Albertini, director of the University of Kansas' Center for Reproductive Sciences. While he has plenty of questions about the latest work, "I'm less skeptical," he said.

Scientists have long taught that all female mammals are born with a finite supply of egg cells, called ooctyes, that runs out in middle age. Tilly, Mass General's reproductive biology director, first challenged that notion in 2004, reporting that the ovaries of adult mice harbor some egg-producing stem cells. Recently, Tilly noted, a lab in China and another in the U.S. also have reported finding those rare cells in mice.

But do they exist in women? Enter the new work, reported Sunday in the journal Nature Medicine.

First Tilly had to find healthy human ovaries to study. He collaborated with scientists at Japan's Saitama Medical University, who were freezing ovaries donated for research by healthy 20-somethings who underwent a sex-change operation.

Tilly also had to address a criticism: How to tell if he was finding true stem cells or just very immature eggs. His team latched onto a protein believed to sit on the surface of only those purported stem cells and fished them out. To track what happened next, the researchers inserted a gene that makes some jellyfish glow green into those cells. If the cells made eggs, those would glow, too.

"Bang, it worked — cells popped right out" of the human tissue, Tilly said.

Researchers watched through a microscope as new eggs grew in a lab dish. Then came the pivotal experiment: They injected the stem cells into pieces of human ovary. They transplanted the human tissue under the skin of mice, to provide it a nourishing blood supply. Within two weeks, they reported telltale green-tinged egg cells forming.

That's still a long way from showing they'll mature into usable, quality eggs, Albertini said.

And more work is needed to tell exactly what these cells are, cautioned reproductive biologist Kyle Orwig of the University of Pittsburgh Medical Center, who has watched Tilly's work with great interest.

But if they're really competent stem cells, Orwig asked, then why would women undergo menopause? Indeed, something so rare wouldn't contribute much to a woman's natural reproductive capacity, added Northwestern's Woodruff.

Tilly argues that using stem cells to grow eggs in lab dishes might one day help preserve cancer patients' fertility. Today, Woodruff's lab and others freeze pieces of girls' ovaries before they undergo fertility-destroying chemotherapy or radiation. They're studying how to coax the immature eggs inside to mature so they could be used for in vitro fertilization years later when the girls are grown. If that eventually works, Tilly says stem cells might offer a better egg supply.

Further down the road, he wonders if it also might be possible to recharge an aging woman's ovaries.

The new research was funded largely by the National Institutes of Health. Tilly co-founded a company, OvaScience Inc., to try to develop the findings into fertility treatments.

Read this article:
Report: Women have rare egg-producing stem cells

By The Associated Press

WASHINGTON — For 60 years, doctors have believed women were born with all the eggs they’ll ever have. Now Harvard scientists are challenging that dogma, saying they’ve discovered the ovaries of young women harbor very rare stem cells capable of producing new eggs.

If Sunday’s report is confirmed, harnessing those stem cells might one day lead to better treatments for women left infertile because of disease — or simply because they’re getting older.

“Our current views of ovarian aging are incomplete. There’s much more to the story than simply the trickling away of a fixed pool of eggs,” said lead researcher Jonathan Tilly of Harvard’s Massachusetts General Hospital, who has long hunted these cells in a series of controversial studies.

Tilly’s previous work drew fierce skepticism, and independent experts urged caution about the latest findings.

A key next step is to see whether other laboratories can verify the work. If so, then it would take years of additional research to learn how to use the cells, said Teresa Woodruff, fertility preservation chief at Northwestern University’s Feinberg School of Medicine.

Still, even a leading critic said such research may help dispel some of the enduring mystery surrounding how human eggs are born and mature.

“This is going to spark renewed interest, and more than anything else it’s giving us some new directions to work in,” said David Albertini, director of the University of Kansas’ Center for Reproductive Sciences. While he has plenty of questions about the latest work, “I’m less skeptical,” he said.

Scientists have long taught that all female mammals are born with a finite supply of egg cells, called ooctyes, that runs out in middle age. Tilly, Mass General’s reproductive biology director, first challenged that notion in 2004, reporting that the ovaries of adult mice harbor some egg-producing stem cells. Recently, Tilly noted, a lab in China and another in the U.S. also have reported finding those rare cells in mice.

But do they exist in women? Enter the new work, reported Sunday in the journal Nature Medicine.

First, Tilly had to find healthy human ovaries to study. He collaborated with scientists at Japan’s Saitama Medical University, who were freezing ovaries donated for research by healthy 20-somethings who underwent a sex-change operation. Continued...

Tilly also had to address a criticism: How to tell if he was finding true stem cells or just very immature eggs. His team latched onto a protein believed to sit on the surface of only those purported stem cells and fished them out. To track what happened next, the researchers inserted a gene that makes some jellyfish glow green into those cells. If the cells made eggs, those would glow, too.

“Bang, it worked — cells popped right out” of the human tissue, Tilly said.

Researchers watched through a microscope as new eggs grew in a lab dish. Then came the pivotal experiment: They injected the stem cells into pieces of human ovary. They transplanted the human tissue under the skin of mice, to provide it a nourishing blood supply. Within two weeks, they reported telltale green-tinged egg cells forming.

That’s still a long way from showing they’ll mature into usable, quality eggs, Albertini said.

And more work is needed to tell exactly what these cells are, cautioned reproductive biologist Kyle Orwig of the University of Pittsburgh Medical Center, who has watched Tilly’s work with great interest.

But if they’re really competent stem cells, Orwig asked, then why would women undergo menopause? Indeed, something so rare wouldn’t contribute much to a woman’s natural reproductive capacity, added Northwestern’s Woodruff.

Tilly argues that using stem cells to grow eggs in lab dishes might one day help preserve cancer patients’ fertility. Today, Woodruff’s lab and others freeze pieces of girls’ ovaries before they undergo fertility-destroying chemotherapy or radiation. They’re studying how to coax the immature eggs inside to mature so they could be used for in vitro fertilization years later when the girls are grown. If that eventually works, Tilly says stem cells might offer a better egg supply.

Further down the road, he wonders if it also might be possible to recharge an aging woman’s ovaries.

The new research was funded largely by the National Institutes of Health. Tilly co-founded a company, OvaScience Inc., to try to develop the findings into fertility treatments.

More here:
Report: Stem cells may create new eggs

WASHINGTON -- For 60 years, doctors have believed women were born with all the eggs they'll ever have. Now Harvard scientists are challenging that dogma, saying they've discovered the ovaries of young women harbor very rare stem cells capable of producing new eggs.

If Sunday's report is confirmed, harnessing those stem cells might one day lead to better treatments for women left infertile because of disease -- or simply because they're getting older.

"Our current views of ovarian aging are incomplete. There's much more to the story than simply the trickling away of a fixed pool of eggs," said lead researcher Jonathan Tilly of Harvard's Massachusetts General Hospital, who has long hunted these cells in a series of controversial studies.

Tilly's previous work drew fierce skepticism, and independent experts urged caution about the latest findings.

A key next step is to see whether other laboratories can verify the work. If so, then it would take years of additional research to learn how to use the cells, said Teresa Woodruff, fertility preservation chief at Northwestern University's Feinberg School of Medicine.

Still, even a leading critic said such research may help dispel some of the enduring mystery surrounding how human eggs are born and mature.

"This is going to spark renewed interest, and more than anything else it's giving us some new directions to work in," said David Albertini, director of the University of Kansas' Center for Reproductive Sciences. While he has plenty of questions about the latest work, "I'm less skeptical," he said.

Scientists have long taught that all female mammals are born with a finite supply of egg cells, called ooctyes, that runs out in middle age. Tilly, Mass General's reproductive biology director, first challenged that notion in 2004, reporting that the ovaries of adult mice harbor some egg-producing stem cells. Recently, Tilly noted, a lab in China and another in the U.S. also have reported finding those rare cells in mice.

But do they exist in women? Enter the new work, reported Sunday in the journal Nature Medicine.

First Tilly had to find healthy human ovaries to study. He collaborated with scientists at Japan's Saitama Medical University, who were freezing ovaries donated for research by healthy 20-somethings who underwent a sex-change operation.

Tilly also had to address a criticism: How to tell if he was finding true stem cells or just very immature eggs. His team latched onto a protein believed to sit on the surface of only those purported stem cells and fished them out. To track what happened next, the researchers inserted a gene that makes some jellyfish glow green into those cells. If the cells made eggs, those would glow, too.

"Bang, it worked -- cells popped right out" of the human tissue, Tilly said.

Researchers watched through a microscope as new eggs grew in a lab dish. Then came the pivotal experiment: They injected the stem cells into pieces of human ovary. They transplanted the human tissue under the skin of mice, to provide it a nourishing blood supply. Within two weeks, they reported telltale green-tinged egg cells forming.

That's still a long way from showing they'll mature into usable, quality eggs, Albertini said.

And more work is needed to tell exactly what these cells are, cautioned reproductive biologist Kyle Orwig of the University of Pittsburgh Medical Center, who has watched Tilly's work with great interest.

But if they're really competent stem cells, Orwig asked, then why would women undergo menopause? Indeed, something so rare wouldn't contribute much to a woman's natural reproductive capacity, added Northwestern's Woodruff.

Tilly argues that using stem cells to grow eggs in lab dishes might one day help preserve cancer patients' fertility. Today, Woodruff's lab and others freeze pieces of girls' ovaries before they undergo fertility-destroying chemotherapy or radiation. They're studying how to coax the immature eggs inside to mature so they could be used for in vitro fertilization years later when the girls are grown. If that eventually works, Tilly says stem cells might offer a better egg supply.

Further down the road, he wonders if it also might be possible to recharge an aging woman's ovaries.

The new research was funded largely by the National Institutes of Health. Tilly co-founded a company, OvaScience Inc., to try to develop the findings into fertility treatments.

See the rest here:
Ovary stem cells can produce new eggs, researchers say

February 27, 2012, 12:41 AM EST

By Ryan Flinn

Feb. 27 (Bloomberg) -- Stem cells taken from human ovaries were used to produce early-stage eggs by scientists in Boston who may have created a new method to help infertile women.

Females have a fixed number of eggs from birth that are depleted by the time of menopause. The finding, published today in the journal Nature Medicine, challenges the belief that their ovaries can’t make more. The research was led by Jonathan Tilly, the director of Massachusetts General Hospital’s Vincent Center for Reproductive Biology.

Tilly reported in 2004 that ovarian stem cells in mice create new eggs, or oocytes, in a way similar to how stem cells in male testes produce sperm throughout a man’s life. His latest work, if reproduced, would suggest the same is true for human ovaries, potentially pointing at new ways to aid fertility by delaying when the ovaries stop functioning.

“The 50-year-old belief in our field wasn’t actually based on data proving it was impossible, or not ongoing,” Tilly said in a telephone interview. “It was simply an assumption made because there was no evidence indicating otherwise. We have human cells that can produce new oocytes.”

In the study, healthy ovaries were obtained from consenting patients undergoing sex reassignment surgery. The researchers were able to identify ovarian stem cells because they express a rare protein that’s only seen in reproductive cells.

The stem cells from the ovaries were injected into human ovarian tissue that was then grafted under the skin of mice, which provided the blood supply that enabled growth. Within two weeks, early stage human follicles with oocytes had formed.

7-Million Eggs

A female is most endowed with oocytes, or eggs, as a fetus, when she has about 7 million. That number that drops to 1 million by birth, and around 300,000 by puberty. By menopause, the number is zero. Since the 1950’s, scientists thought that ovarian stem cells capable of producing new eggs are only active during fetal development.

“This paper essentially opens the door to the ability to control oocyte development in human ovaries,” Tilly said.

About 10 percent of women of child-bearing age in the U.S., or 6.1 million, have difficulty getting pregnant or staying pregnant, according to the Centers for Disease Control and Prevention. Most cases of female infertility are caused by problems with ovulation, hormone imbalance or age.

The study by Tilley and his colleagues offers “a new model system for understanding the human egg cell,” said David F. Albertini, director of the Center for Reproductive Services and professor in the department of molecular and integrative physiology at Kansas University, in a telephone interview.

‘Practical Applications”

Still, “there’s a long way to go before this has real practical applications. I’ve spent 35 years of my life studying egg cells and this is a cell that is at least as complicated as a neuron in the brain, if not more,” Albertini said.

The work needs to be reproduced and expanded by other scientists “to make it into something that will make us confident the cells are safe to use and we could actually use them to repopulate an egg-depleted ovary,” he said.

Tilly’s team is exploring the development of an ovarian stem-cell bank that can be cryogenically frozen and thawed without damage, unlike human eggs, he said. The researchers are also working to identify hormones and other growth factors for accelerating production of eggs from human ovarian stem cells and ways to improve in-vitro fertilization.

“The problem we face with IVF is we don’t have many eggs to work with,” he said. “These cells are renewable. If we are successful -- and it’s a big if -- in generating functioning eggs from these cells, we can generate as many eggs as we need to on a per patient basis.”

Tilly is also collaborating with researchers at the University of Edinburgh in the U.K. to determine whether the oocytes can be developed into fully mature human eggs for fertilizing. The U.S bans creating or fertilizing embryos for experimental purposes, he said.

A company Tilly co-founded, Boston-based OvaScience Inc., has licensed the technology for potential commercial applications.

--With assistance from Sarah Frier in New York. Editors: Angela Zimm, Andrew Pollack

To contact the reporter on this story: Ryan Flinn in San Francisco at rflinn@bloomberg.net

To contact the editor responsible for this story: Reg Gale at rgale5@bloomberg.net

See the article here:
Ovarian Stem Cells Produce Eggs in Method That May Aid Fertility

By Ryan Flinn - Mon Feb 27 05:00:01 GMT 2012

Stem cells taken from human ovaries were used to produce early-stage eggs by scientists in Boston who may have created a new method to help infertile women.

Females have a fixed number of eggs from birth that are depleted by the time of menopause. The finding, published today in the journal Nature Medicine, challenges the belief that their ovaries can’t make more. The research was led by Jonathan Tilly, the director of Massachusetts General Hospital’s Vincent Center for Reproductive Biology.

Tilly reported in 2004 that ovarian stem cells in mice create new eggs, or oocytes, in a way similar to how stem cells in male testes produce sperm throughout a man’s life. His latest work, if reproduced, would suggest the same is true for human ovaries, potentially pointing at new ways to aid fertility by delaying when the ovaries stop functioning.

“The 50-year-old belief in our field wasn’t actually based on data proving it was impossible, or not ongoing,” Tilly said in a telephone interview. “It was simply an assumption made because there was no evidence indicating otherwise. We have human cells that can produce new oocytes.”

In the study, healthy ovaries were obtained from consenting patients undergoing sex reassignment surgery. The researchers were able to identify ovarian stem cells because they express a rare protein that’s only seen in reproductive cells.

The stem cells from the ovaries were injected into human ovarian tissue that was then grafted under the skin of mice, which provided the blood supply that enabled growth. Within two weeks, early stage human follicles with oocytes had formed.

7-Million Eggs

A female is most endowed with oocytes, or eggs, as a fetus, when she has about 7 million. That number that drops to 1 million by birth, and around 300,000 by puberty. By menopause, the number is zero. Since the 1950’s, scientists thought that ovarian stem cells capable of producing new eggs are only active during fetal development.

“This paper essentially opens the door to the ability to control oocyte development in human ovaries,” Tilly said.

About 10 percent of women of child-bearing age in the U.S., or 6.1 million, have difficulty getting pregnant or staying pregnant, according to the Centers for Disease Control and Prevention. Most cases of female infertility are caused by problems with ovulation, hormone imbalance or age.

The study by Tilley and his colleagues offers “a new model system for understanding the human egg cell,” said David F. Albertini, director of the Center for Reproductive Services and professor in the department of molecular and integrative physiology at Kansas University, in a telephone interview.

‘Practical Applications”

Still, “there’s a long way to go before this has real practical applications. I’ve spent 35 years of my life studying egg cells and this is a cell that is at least as complicated as a neuron in the brain, if not more,” Albertini said.

The work needs to be reproduced and expanded by other scientists “to make it into something that will make us confident the cells are safe to use and we could actually use them to repopulate an egg-depleted ovary,” he said.

Tilly’s team is exploring the development of an ovarian stem-cell bank that can be cryogenically frozen and thawed without damage, unlike human eggs, he said. The researchers are also working to identify hormones and other growth factors for accelerating production of eggs from human ovarian stem cells and ways to improve in-vitro fertilization.

“The problem we face with IVF is we don’t have many eggs to work with,” he said. “These cells are renewable. If we are successful -- and it’s a big if -- in generating functioning eggs from these cells, we can generate as many eggs as we need to on a per patient basis.”

Tilly is also collaborating with researchers at the University of Edinburgh in the U.K. to determine whether the oocytes can be developed into fully mature human eggs for fertilizing. The U.S bans creating or fertilizing embryos for experimental purposes, he said.

A company Tilly co-founded, Boston-based OvaScience Inc., has licensed the technology for potential commercial applications.

To contact the reporter on this story: Ryan Flinn in San Francisco at rflinn@bloomberg.net

To contact the editor responsible for this story: Reg Gale at rgale5@bloomberg.net

Read this article:
Ovarian Stem Cells Produce Eggs in Method That May Aid Fertility Therapy

February 27, 2012, 12:41 AM EST

By Ryan Flinn

Feb. 27 (Bloomberg) -- Stem cells taken from human ovaries were used to produce early-stage eggs by scientists in Boston who may have created a new method to help infertile women.

Females have a fixed number of eggs from birth that are depleted by the time of menopause. The finding, published today in the journal Nature Medicine, challenges the belief that their ovaries can’t make more. The research was led by Jonathan Tilly, the director of Massachusetts General Hospital’s Vincent Center for Reproductive Biology.

Tilly reported in 2004 that ovarian stem cells in mice create new eggs, or oocytes, in a way similar to how stem cells in male testes produce sperm throughout a man’s life. His latest work, if reproduced, would suggest the same is true for human ovaries, potentially pointing at new ways to aid fertility by delaying when the ovaries stop functioning.

“The 50-year-old belief in our field wasn’t actually based on data proving it was impossible, or not ongoing,” Tilly said in a telephone interview. “It was simply an assumption made because there was no evidence indicating otherwise. We have human cells that can produce new oocytes.”

In the study, healthy ovaries were obtained from consenting patients undergoing sex reassignment surgery. The researchers were able to identify ovarian stem cells because they express a rare protein that’s only seen in reproductive cells.

The stem cells from the ovaries were injected into human ovarian tissue that was then grafted under the skin of mice, which provided the blood supply that enabled growth. Within two weeks, early stage human follicles with oocytes had formed.

7-Million Eggs

A female is most endowed with oocytes, or eggs, as a fetus, when she has about 7 million. That number that drops to 1 million by birth, and around 300,000 by puberty. By menopause, the number is zero. Since the 1950’s, scientists thought that ovarian stem cells capable of producing new eggs are only active during fetal development.

“This paper essentially opens the door to the ability to control oocyte development in human ovaries,” Tilly said.

About 10 percent of women of child-bearing age in the U.S., or 6.1 million, have difficulty getting pregnant or staying pregnant, according to the Centers for Disease Control and Prevention. Most cases of female infertility are caused by problems with ovulation, hormone imbalance or age.

The study by Tilley and his colleagues offers “a new model system for understanding the human egg cell,” said David F. Albertini, director of the Center for Reproductive Services and professor in the department of molecular and integrative physiology at Kansas University, in a telephone interview.

‘Practical Applications”

Still, “there’s a long way to go before this has real practical applications. I’ve spent 35 years of my life studying egg cells and this is a cell that is at least as complicated as a neuron in the brain, if not more,” Albertini said.

The work needs to be reproduced and expanded by other scientists “to make it into something that will make us confident the cells are safe to use and we could actually use them to repopulate an egg-depleted ovary,” he said.

Tilly’s team is exploring the development of an ovarian stem-cell bank that can be cryogenically frozen and thawed without damage, unlike human eggs, he said. The researchers are also working to identify hormones and other growth factors for accelerating production of eggs from human ovarian stem cells and ways to improve in-vitro fertilization.

“The problem we face with IVF is we don’t have many eggs to work with,” he said. “These cells are renewable. If we are successful -- and it’s a big if -- in generating functioning eggs from these cells, we can generate as many eggs as we need to on a per patient basis.”

Tilly is also collaborating with researchers at the University of Edinburgh in the U.K. to determine whether the oocytes can be developed into fully mature human eggs for fertilizing. The U.S bans creating or fertilizing embryos for experimental purposes, he said.

A company Tilly co-founded, Boston-based OvaScience Inc., has licensed the technology for potential commercial applications.

--With assistance from Sarah Frier in New York. Editors: Angela Zimm, Andrew Pollack

To contact the reporter on this story: Ryan Flinn in San Francisco at rflinn@bloomberg.net

To contact the editor responsible for this story: Reg Gale at rgale5@bloomberg.net

See the original post here:
Ovarian Stem Cells Make Human Eggs in Possible Aid to Fertility

The latest discoveries and promises of stem cell research and the development of new therapeutic approaches for a variety of diseases will be in focus at the Qatar International Conference on Stem Cell Science and Policy 2012 which begins today.
The four-day event, being held at Qatar National Convention Centre, is a milestone in Qatar Foundation’s ongoing collaboration with the James A Baker III Institute for Public Policy at Rice University, Houston, Texas, US.
The aim of QF’s joint initiative with the Baker Institute’s International Programme on Stem Cell Science Policy is to develop stem cell research in Qatar as well as to find ways to address the shared challenges of community support for stem cell research in Doha and Houston.
To accomplish this goal, the programme has supported several events since its inception, including meetings, workshops, and training programmes in both cities.
The conference, which brings together eminent international as well as regional scientists, ethicists and policymakers, will also present the developed policy options that account for cultural, ethical and religious factors.
The event will draw attention to Qatar’s position in the development of stem cell research in the region and the world, given that research on stem cell as a national priority has already been initiated in the country’s best research institutions.
The conference objectives are to raise the awareness about Qatar’s initiative in promoting stem cell research, present the latest developments, and highlight the different religious views regarding stem cell research specifically the Islamic view.
The pros and cons of various options for regulating stem cell research and how scientists should address conflicting and confusing national policies and assess the different models of international collaboration will be discussed.
The conference also intends to interface with other institutions outside Qatar and contribute to the exchange of scientific knowledge to enhance the promotion of a scientific culture in the region and globally.
The keynote speakers are ambassador Edward P Djerejian (Baker Institute), Irving Weissman (Stanford University), Alan Trounson (president, California Institute for Regenerative Medicine), David Baltimore (president emeritus, Robert Andrews Millikan Professor of Biology, California Institute of Technology), Roger Pedersen (Department of Surgery, University of Cambridge) and Lawrence Corey (president and director, Fred Hutchinson Cancer Research Centre).
The conference, supported by Qatar Biomedical Research Institute, will also feature a number of invited speakers from across the world.

Link:
Seminar to focus on stem cell research development

Researchers have isolated egg-producing stem cells from the ovaries of reproductive age women and shown these can produce what appear to be normal egg cells or oocytes, according to a new study.

The discovery "opens the door for development of unprecedented technologies to overcome infertility in women" according to the scientist who led the study.

Jonathan Tilly, of Massachusetts General Hospital in the United States, said: "The primary objective of the current study was to prove that oocyte-producing stem cells do in fact exist in the ovaries of women during reproductive life, which we feel this study demonstrates very clearly."

The researchers developed a precise cell-sorting technique to isolate oocyte producing stem cells (OSCs) without contamination from other cells, according to an article in the March issue of Nature Medicine.

The cells were able, in the laboratory, to form cells spontaneously with characteristic features of oocytes. Further experiments on mice showed such eggs could be fertilised.

Dr Tilly's team is exploring potential clinical applications from its findings which include the establishment of human OSC banks - since these cells, unlike human oocytes, can be frozen and thawed without damage - and the development of mature human oocytes from OSCs for in vitro fertilisation, plus other approaches to improve the outcomes of IVF and other infertility treatments.

In 2004 a report from Dr Tilly's team challenged the fundamental belief, held since the 1950s, that female mammals are born with a finite supply of eggs that is depleted throughout life and exhausted at menopause.

Dr Tilly said: "The discovery of oocyte precursor cells in adult human ovaries, coupled with the fact that these cells share the same characteristic features of their mouse counterparts that produce fully functional eggs, opens the door for development of unprecedented technologies to overcome infertility in women and perhaps even delay the timing of ovarian failure."

Dr Allan Pacey, a fertility expert at the University of Sheffield, told the BBC: "This is a nice study which shows quite convincingly that women's ovaries contain stem cells that can divide and make eggs.

"Not only does this re-write the rule book, it opens up a number of exciting possibilities for preserving the fertility of women undergoing treatment for cancer, or just maybe for women who are suffering infertility by extracting these cells and making her new eggs in the lab."

Read the original:
Stem cell boost in fertility study

By Carolyn Y. Johnson, Globe Staff

Massachusetts General Hospital researchers reported today they have discovered a rare stem cell in women’s ovaries that they hope one day might be used to make eggs, a claim already generating vigorous debate among scientists familiar with the research.

For decades, it has been thought that women are born with a finite supply of eggs, limiting their reproductive years. Doctors have sought ways of extending the fertility of women, especially as many wait later in life to begin having children.

The research, led by Jonathan Tilly of Mass. General and appearing in the journal Nature Medicine, opens the door to the possibility of taking tissue from a woman’s ovaries, harvesting stem cells from that tissue, and then creating eggs.

But scientists not involved with the Mass. General research said such an approach -- if it is even possible -- sits far in the future and will require considerably more work. Several scientists said Tilly, who co-founded a company focused on developing novel infertility treatments, had not yet made a convincing case that the stem cells he discovered can yield viable eggs, a critical first step.

Tilly has been a lightning rod in the field of fertility medicine since 2004, when he challenged the orthodoxy that women do not produce new eggs. In a research paper published that year, Tilly laid the foundation for the findings reported yesterday.

“There was a lot of backlash. It wasn’t surprising, given the magnitude of the paradigm shift that was being proposed -- this was one of the fundamental beliefs in our field,” Tilly said. “The subsequent eight years have been a long haul.”

In his new study, Tilly extended research by Chinese scientists published in 2009. He developed a technique that allowed scientists to sift out rare stem cells within the ovaries of mice that were tagged and implanted into the ovaries of normal mice. In the mouse ovaries, the stem cells produced eggs, which were removed and fertilized in a laboratory dish. They developed into embryos, although scientists did not use the embryos to produce mice.

Tilly and his team then wanted to know if such cells existed in humans, too.

The research team obtained ovarian tissue removed from young women undergoing sex change operations in Japan and performed the same experiment they’d done with the mouse ovaries. Much to their excitement, they discovered the rare, egg-producing cells in humans.

In later experiments, the human stem cells were used to produce cells that appeared to be eggs. In part because of ethical limitations, researchers were not able to show that the eggs could be used to create human embryos.

Tilly said that he has patented the stem cells and licensed the technology to OvaScience, the startup he co-founded.

Outside researchers described the findings as intriguing and provocative but also raised many questions. Scientists said it was still far from certain that the eggs created in the experiments could be used to produce babies. And they expressed concern that the findings could falsely inflate the hopes of women struggling with infertility.

Dr. David Keefe, chairman of obstetrics and gynecology at New York University Langone Medical Center, said he and other clinicians who see patients would like more than anything to have greater options for women to overcome infertility. But he said the Mass. General researcher had a history of leaping ahead from basic research findings to suggest clinical possibilities.

“Those of us who take care of patients are extremely protective of their hopes,” Keefe said. He noted that a few years ago, he saw half-a-dozen patients who wanted to delay their fertility decisions because of earlier research at Mass. General.

Even if the new findings are immediately replicated in labs around the world, Keefe said, “it’s so far from being clinical that it’s predatory to not be circumspect about it. Humility is an absolute requirement in this field. You’re dealing with people’s hopes and dreams.”

A 2005 study led by Tilly and done in mice suggested bone marrow transplants might offer a way to restore fertility. A year later, a separate group of Harvard researchers showed that this was unlikely to be true. Tilly himself no longer believes this is a way to restore fertility.

“The big difference in that work, now in retrospect, is these non-ovarian sources [of stem cells] don’t appear to do the job,” he said.

Tilly’s work in the past has divided researchers and failed to persuade many in the field that his interpretations are correct.

Teresa Woodruff, a professor of obstetrics and gynecology at the Feinberg School of Medicine at Northwestern University said she had already drawn up a chart of the claims made in the paper, the evidence to support those claims, and the questions they raise. Still, she said, “I do think he’s pushing the envelope in a way that does push all of us to think more broadly.”

Evelyn Telfer, a cell biologist at the University of Edinburgh, who criticized some of Tilly’s earlier work, said she is excited about the new findings. Tilly said that next month, he will fly to Scotland to begin a collaboration with Telfer.

“What he’s saying is we can get these cells,” Telfer said, “and I think it’s pretty convincing.”

The new paper doesn’t offer evidence that such stem cells are active in the ovary, supplying eggs during a woman’s lifetime. But the powerful cells could provide new insights into the important and poorly understood process in biology of egg-formation and allow scientists to look for drugs that might increase the activities of these stem cells, in order to overcome fertility problems.

Skeptics and supporters agreed on one thing: much work lies ahead.

“That’s science,” said Hugh Clarke, a professor in the department of obstetrics and gynecology at McGill University. “Of course, dogma should be challenged, but we shouldn’t assume dogma has been overturned based on a single report.”

Carolyn Y. Johnson can be reached at cjohnson@globe.com. Follow her on Twitter @carolynyjohnson.

Visit link:
Massachusetts General researchers discover stem cell that makes eggs

by: John Phillip

Researchers publishing in the Canadian Journal of Physiology and Pharmacology (CJPP) have found that a diet enhanced with vitamin and mineral supplementation can lower the risk of developing precancerous colon cancer lesions by up to 84%. Colon cancer is the second most common form of the disease affecting men and women in the US, with nearly 150,000 new diagnoses each year.

Nutrition experts and alternative practitioners understand that cancer is largely a disease caused by poor lifestyle behaviors including a diet lacking an optimal intake of vitamins and minerals. Chronic illnesses including colon cancer are the result of many years and decades of low nutritional status, as support for a healthy immune response is suppressed. Scientists now provide compelling evidence in support of whole-food based vitamin and mineral supplementation to dramatically lower the risk of colorectal cancer. Read more...

AyurGold for Healthy Blood

Source:
http://feeds.feedburner.com/integratedmedicine

Hindu Business Line

My decision on Bt brinjal was not influenced by NGOs: Jairam Expressindia.com New Delhi Days after Prime Minister Manmohan Singh spoke of the role of foreign-funded NGOs in instigating protests against genetic engineering in agriculture, Rural Development Minister Jairam Ramesh has asserted that his controversial decision to put ... Decision on Bt. Brinjal not influenced by NGOs: JairamTwoCircles.net No NGO pressure in Bt Brinjal moratorium: JairamDaily Bhaskar Jairam differs with PM, says no NGO forced Bt Brinjal banHindustan Times all 31 news articles »

Source:
http://news.google.com/news?q=genetic-engineering&output=rss

DigitalJournal.com

The GMO Debate, Food For Thought Part 1 KITV Honolulu Genetic Engineering has entered our food chain in a big way. In 2012, more than half of the crops grown in the United States are GMOs. According to the USDA, 88% of all corn crops, 90% of cotton crops, and 94% of soybean crops are GMO crops. GMO LabelingManila Bulletin all 13 news articles »

Source:
http://news.google.com/news?q=genetic-engineering&output=rss