Adult Stem Cells Growing Strong

Wise Young · 08-04-2001, 06:07 AM

Because we don't have access to the previous forums, I am posting some older news articles that are relevant to our discussion. Wise.

-------------------------------------------------------------
From Wired News, available online at:
http://www.wired.com/news/print/0,1294,42761,00.html
http://www.wired.com/news/print/0,1294,42761,00.html

Adult Stem Cells Growing Strong
by Kristen Philipkoski

1:00 p.m. Mar. 30, 2001 PST

Two studies are poised to quell one of the most controversial issues in medical research today: the use of embryonic or fetal stem cells to regenerate damaged organs.

The research shows promise in using stem cells taken from adults to grow new heart muscle and blood vessels.

The investigators have seen success only in mice so far, but some of the researchers believe they'll get approval from the Food and Drug Administration to perform human trials as soon as one year from now.

The studies add to a growing body of research suggesting that stem cells taken from adult bone marrow could be as effective at regenerating damaged organs as those taken from an embryo or fetus. If so, the huge controversy over the ethical implications of using fetal or embryonic cells could be moot.

"There are obviously no ethical issues with human adult autologous stem cell therapy," said Dr. Silviu Itescu, director of transplantation immunology at the Columbia-Presbyterian Medical Center in New York City.

Itescu's study is published in today's issue of Nature Medicine. Another study will be published in the April 4 issue of Nature.

Itescu induced mouse hearts to grow healthy blood vessels in the heart after stem cells were injected into their tails. The Nature paper will show mice growth of not only blood vessels, but also new muscle.

"It gives me tremendous hope for the future of adult stem cell research. They are so much more plastic (malleable) than anyone had ever imagined," said Dr. Donald Orlic of the National Human Genome Research Institute.

Embryonic and fetal stem cells are like a clean slate. They have the ability to grow into any type of cell in the human body, a process called differentiation. Most stem cell researchers have believed that embryonic and fetal stem cells have a superior ability to regenerate and differentiate.

Researchers take adult stem cells from bone marrow, and then have to "de-differentiate" the cells to get a clean slate.

The treatment has implications for any disease or injury that results in damaged organs: Parkinson's, Alzheimer's, spinal cord injuries, just to name a few.

Last year, the Clinton administration utilized a loophole in a ban against using federal funds for research on human embryos. He declared that research on stem cells obtained from private researchers was OK, but embryonic cells could not be created or destroyed using government money.

President Bush has promised to reexamine this regulation, and most expect that in June he will announce that studies on human fetal or embryonic stem cells will no longer receive federal funding. Health and Human Services director Tommy Thompson is anti-abortion. But he has praised the University of Wisconsin biologist who isolated the first embryonic stem cells in 1998 and even threw a party to celebrate it. Researchers hope he will influence the president. But he made comments in recent Senate committee meetings indicating that his stance is unclear.

Critics have speculated that if Bush were to direct money to adult stem cell research, it would be a political move to pacify both sides of the controversy.

Itescu said his research could be tested in humans in as little as a year.

The study will lead to the "establishment of a clinical trial evaluating the use of human adult endothelial stem cells to prevent heart failure after myocardial infarction (heart attack) within 12 months," he said.

Orlic and his colleague Dr. Piero Anversa of the New York Medical College in Valhalla, New York, believe it could take closer to three years for their technique to be tested on humans.

"We must... show that the same thing can occur in the heart of a non-human primate," Orlic said. "If we can do that, then I think we can get permission from the FDA for a clinical trial in three years."

A recent human study on Parkinson's patients at Johns Hopkins University was a blow to fetal stem cell research. Stem cells from aborted fetuses were injected into the patient's brains. The stem cells reproduced and grew into neural cells but also over-produced dopamine, causing severe involuntary jerking and twitching.

Orlic said fetal and embryonic stem cell researchers have not been able to show the regeneration of heart cells, even in animals.

"This study alone gives us tremendous hope that adult stem cells can do more than what embryonic stem cells can do," he said.

Related Wired Links:

Cell Switch Stems Stem Cell Snit?
Mar. 1, 2001

All the World's a Stage of DNA
Feb. 10, 2001

Bioethics in the Hot Seat
Jan. 18, 2001

When God and Genes Mixed Well
Jan. 8, 2001

Gore, Bush Proxies Irk Bio Crowd
Nov. 2, 2000

Adult Approach to Stem Cells
Sep. 19, 2000

Stem-Cell Researchers Skirt Regs
Sep. 8, 2000

Copyright (C) 1994-2001 Wired Digital Inc. All rights reserved.

rdf · 08-04-2001, 09:05 PM

If all cells are originally stem cells until differentiation, how far are we away from turning every type of adult cell back to being a stem cell, via de-differentiation? Is this even possible?

How are adult stem cells different from esc's? Have they differentiated into an adult stem cell? Or have they turned into an adult cell, then differentiated on their own back to an adult stem cell?
Or are they "tramp" cells, moving from one cell line to another as needed, not continuing always to be one specific cell. Could you explain Wise? Thank

Wise Young · 08-05-2001, 10:55 AM

Great questions. Scientists would like to know the answers to these questions, too. Some clues exist and you can come to your own conclusions.

1. Can cells de-differentiate back to stem cells. There is as yet no convincing data that any fully differentiated cell can turn back into a stem cell. However, the line between so-called precursor (or progenitor) cells and stem cells are less clear. Precursor cells are more restricted than stem cells in that they cannot produce all kinds of cells. For example, there are neural-restricted precursors (NRPs) and glia-restricted precursors (GRPs) that apparently can only produce neurons and glia respectively. Of course, as you know, there are many kinds of neurons and glial cells. In the bone marrow, there are stem cells but these are different from the precursor cells that produce blood cells. Bone marrow stem cells apparently have the ability to form neurons and glia.

2. Migratory ability of adult and embryonic stem cells. This is only a recently discovered trait of stem cells. Last year, when Mezey, et al. and Brazelton, et al. reported that they were able to inject bone marrow stem cells systemically and the cells migrated into the brain and formed neurons, this came as a shocker to the whole scientific community. It raised the possibility that stem cells are like the itinerant gunslinger ("have gun, will travel") and go around from town to town to do good deeds. Nobody knows whether all stem cells or some stem cells have this ability, what factors controls the migration of stem cells. Common sense tells us that there are some restrictions on the migration of stem cells and also controls on the numbers of stem cells in the body. They also pose a danger because they might be the source of natural cancers.

Wise.

08-04-2001, 06:07 AM	#1
Wise Young Administrator Join Date: Jul 2001 Location: New Brunswick, NJ, USA Posts: 37,975	Adult Stem Cells Growing Strong Because we don't have access to the previous forums, I am posting some older news articles that are relevant to our discussion. Wise. ------------------------------------------------------------- From Wired News, available online at: http://www.wired.com/news/print/0,1294,42761,00.html http://www.wired.com/news/print/0,1294,42761,00.html Adult Stem Cells Growing Strong by Kristen Philipkoski 1:00 p.m. Mar. 30, 2001 PST Two studies are poised to quell one of the most controversial issues in medical research today: the use of embryonic or fetal stem cells to regenerate damaged organs. The research shows promise in using stem cells taken from adults to grow new heart muscle and blood vessels. The investigators have seen success only in mice so far, but some of the researchers believe they'll get approval from the Food and Drug Administration to perform human trials as soon as one year from now. The studies add to a growing body of research suggesting that stem cells taken from adult bone marrow could be as effective at regenerating damaged organs as those taken from an embryo or fetus. If so, the huge controversy over the ethical implications of using fetal or embryonic cells could be moot. "There are obviously no ethical issues with human adult autologous stem cell therapy," said Dr. Silviu Itescu, director of transplantation immunology at the Columbia-Presbyterian Medical Center in New York City. Itescu's study is published in today's issue of Nature Medicine. Another study will be published in the April 4 issue of Nature. Itescu induced mouse hearts to grow healthy blood vessels in the heart after stem cells were injected into their tails. The Nature paper will show mice growth of not only blood vessels, but also new muscle. "It gives me tremendous hope for the future of adult stem cell research. They are so much more plastic (malleable) than anyone had ever imagined," said Dr. Donald Orlic of the National Human Genome Research Institute. Embryonic and fetal stem cells are like a clean slate. They have the ability to grow into any type of cell in the human body, a process called differentiation. Most stem cell researchers have believed that embryonic and fetal stem cells have a superior ability to regenerate and differentiate. Researchers take adult stem cells from bone marrow, and then have to "de-differentiate" the cells to get a clean slate. The treatment has implications for any disease or injury that results in damaged organs: Parkinson's, Alzheimer's, spinal cord injuries, just to name a few. Last year, the Clinton administration utilized a loophole in a ban against using federal funds for research on human embryos. He declared that research on stem cells obtained from private researchers was OK, but embryonic cells could not be created or destroyed using government money. President Bush has promised to reexamine this regulation, and most expect that in June he will announce that studies on human fetal or embryonic stem cells will no longer receive federal funding. Health and Human Services director Tommy Thompson is anti-abortion. But he has praised the University of Wisconsin biologist who isolated the first embryonic stem cells in 1998 and even threw a party to celebrate it. Researchers hope he will influence the president. But he made comments in recent Senate committee meetings indicating that his stance is unclear. Critics have speculated that if Bush were to direct money to adult stem cell research, it would be a political move to pacify both sides of the controversy. Itescu said his research could be tested in humans in as little as a year. The study will lead to the "establishment of a clinical trial evaluating the use of human adult endothelial stem cells to prevent heart failure after myocardial infarction (heart attack) within 12 months," he said. Orlic and his colleague Dr. Piero Anversa of the New York Medical College in Valhalla, New York, believe it could take closer to three years for their technique to be tested on humans. "We must... show that the same thing can occur in the heart of a non-human primate," Orlic said. "If we can do that, then I think we can get permission from the FDA for a clinical trial in three years." A recent human study on Parkinson's patients at Johns Hopkins University was a blow to fetal stem cell research. Stem cells from aborted fetuses were injected into the patient's brains. The stem cells reproduced and grew into neural cells but also over-produced dopamine, causing severe involuntary jerking and twitching. Orlic said fetal and embryonic stem cell researchers have not been able to show the regeneration of heart cells, even in animals. "This study alone gives us tremendous hope that adult stem cells can do more than what embryonic stem cells can do," he said. Related Wired Links: Cell Switch Stems Stem Cell Snit? Mar. 1, 2001 All the World's a Stage of DNA Feb. 10, 2001 Bioethics in the Hot Seat Jan. 18, 2001 When God and Genes Mixed Well Jan. 8, 2001 Gore, Bush Proxies Irk Bio Crowd Nov. 2, 2000 Adult Approach to Stem Cells Sep. 19, 2000 Stem-Cell Researchers Skirt Regs Sep. 8, 2000 Copyright (C) 1994-2001 Wired Digital Inc. All rights reserved.

08-04-2001, 09:05 PM	#2
rdf Senior Member Join Date: Jul 2001 Location: Someplace between Nowhere and Goodbye Posts: 12,611	adult stem cells If all cells are originally stem cells until differentiation, how far are we away from turning every type of adult cell back to being a stem cell, via de-differentiation? Is this even possible? How are adult stem cells different from esc's? Have they differentiated into an adult stem cell? Or have they turned into an adult cell, then differentiated on their own back to an adult stem cell? Or are they "tramp" cells, moving from one cell line to another as needed, not continuing always to be one specific cell. Could you explain Wise? Thank

08-05-2001, 10:55 AM	#3
Wise Young Administrator Join Date: Jul 2001 Location: New Brunswick, NJ, USA Posts: 37,975	rdf Great questions. Scientists would like to know the answers to these questions, too. Some clues exist and you can come to your own conclusions. 1. Can cells de-differentiate back to stem cells. There is as yet no convincing data that any fully differentiated cell can turn back into a stem cell. However, the line between so-called precursor (or progenitor) cells and stem cells are less clear. Precursor cells are more restricted than stem cells in that they cannot produce all kinds of cells. For example, there are neural-restricted precursors (NRPs) and glia-restricted precursors (GRPs) that apparently can only produce neurons and glia respectively. Of course, as you know, there are many kinds of neurons and glial cells. In the bone marrow, there are stem cells but these are different from the precursor cells that produce blood cells. Bone marrow stem cells apparently have the ability to form neurons and glia. 2. Migratory ability of adult and embryonic stem cells. This is only a recently discovered trait of stem cells. Last year, when Mezey, et al. and Brazelton, et al. reported that they were able to inject bone marrow stem cells systemically and the cells migrated into the brain and formed neurons, this came as a shocker to the whole scientific community. It raised the possibility that stem cells are like the itinerant gunslinger ("have gun, will travel") and go around from town to town to do good deeds. Nobody knows whether all stem cells or some stem cells have this ability, what factors controls the migration of stem cells. Common sense tells us that there are some restrictions on the migration of stem cells and also controls on the numbers of stem cells in the body. They also pose a danger because they might be the source of natural cancers. Wise.

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