The disgraced South Korean researcher whose breakthrough cloning research was exposed as a fraud in 2005 now faces up to four years in prison. Prosecutors asked for the four-year sentence in court today, where the researcher, Hwang Woo-suk, is standing trial for fraud, misusing $2.25 million in state funds, and violating bioethics laws by illegally buying human eggs for his research. “The people’s disappointment was very serious because their expectation for his stem cell research had been high,” an unidentified prosecutor told the courtroom. He said Hwang tarnished South Korea’s image abroad…. Hwang pleaded for leniency, saying if the court forgives him he is ready to “pour the last of my passion” into research [AP].
Hwang became a national hero to South Korea in 2004, when he claimed to have cloned human embryonic stem cells, a feat that was thought to be impossible because of the complexities of human cells. Embryonic stem cells are of great interest to medical researchers because they can develop into any kind of adult cell, and could theoretically be used to replace malfunctioning cells that cause disease. A year later, Hwang said the team created human embryonic stem cells genetically matched to specific patients — a purported breakthrough that promised a way to withstand rejection by a patient’s immune system [AP].
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From reprogrammed skin cells, scientists have made live mice.
The accomplishment is the latest step forward in the exciting new field of reprogrammed cells, which may offer an alternative to embryonic stem cells…. [It's] the most definitive evidence yet that the technique could help sidestep many of the explosive ethical issues engulfing the controversial field [Washington Post]. Two new studies describe the process, and one team of researchers reports producing 27 live mice. While there were abnormalities and unusual deaths with some of the first generation of mice, [the] team produced enough normal mice this way to create hundreds of second and third generation mice [AP].
It was only three years ago that Japanese stem cell researchers found a way to reprogram ordinary skin cells to behave like embryonic stem cells, which are thought to hold vast potential for medical research because they can develop into any kind of body tissue–from heart cells to toenail cells. But researchers didn’t know if the reprogrammed adult cells, known as induced pluripotent stem cells or iPS cells, were capable of differentiating into every type of tissue, the way embryonic stem cells do.
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To obtain a steady supply of unfertilized human eggs for medical research, New York’s Empire State Stem Cell Board recently authorized paying women to donate their eggs. The decision has set off a new round of discussion about whether paying for eggs is ethical. The board agreed that women can receive up to $10,000 for donating eggs, a painful and sometimes risky process…. Proponents say compensating women for their eggs is necessary for research, and point out that women who give their eggs for fertility purposes are already paid. Others worry that the practice will commodify the human body and lead to the exploitation of women in financial need [The New York Times].
At the annual meeting of the International Society for Stem Cell Research this week, British researcher Alison Murdoch described a less controversial “egg sharing” program that has met with success. Women struggling to conceive can obtain IVF at a discounted rate, in exchange for donating some of their eggs for research…. In 2008, Murdoch’s team had 191 enquiries from interested women and ended up obtaining 199 eggs from 32 couples. “We are getting donors and we are getting eggs,” says Murdoch. The team is using the eggs in experiments into “therapeutic cloning”, which could ultimately produce stem cells matched to individual patients [New Scientist].
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British researcher Karim Nayernia says he has produced human sperm from embryonic stem cells for the first time, but his claims have been met with some skepticism. Embryonic stem cells can develop into any kind of cell in the body, but researchers have struggled for years to produce reproductive cells from stem cells. The task is particularly difficult because it requires a complex form of cell division called meiosis, which reduces the number of chromosomes per cell by half [Nature News]. In the new study, published in the journal Stem Cells and Development, Nayernia says his team used a special cocktail of growth factors to transform stem cells into sperm.
But male fertility expert Allan Pacey says the lab’s creations are too abnormal to be called sperm. “I am unconvinced from the data presented in this paper that the cells produced by Professor Nayernia’s group from embryonic stem cells can be accurately called ‘spermatazoa.” … Pacey said in a statement that the sperm created by Nayernia did not have the specific shape, movement and function of real sperm [AP].
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Although ethical debates about the use of embryonic stem cells continue to rage, stem cell technology is beginning to make its way into the medical marketplace. Yesterday, General Electric division GE Healthcare announced that it’s teaming up with the biotechnology company Geron in a venture that will use embryonic stem cells to develop products that could give drug developers an early warning of whether new medicines are toxic [Reuters].
The agreement marks the first time that a company of GE’s stature and size has announced a business venture involving the controversial field of embryonic stem cells. That could reflect a more tolerant climate for the technology in the wake of the Obama administration’s recent relaxation of restrictions on embryonic stem-cell research [The Wall Street Journal]. Supporters of embryonic stem cell research say the work will lead to a host of treatments for cancer and other diseases, while opponents believe that the destruction of any human embryo is unacceptable.
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The beating of the heart inside an embryo doesn’t just circulate blood through the developing creature, it also triggers the formation of blood stem cells, the cells that give rise to all other forms of blood cells, according to two new studies. The surprising findings show that the physical force of the heartbeat and blood flowing through the aorta cause embryonic stem cells to differentiate–although researchers don’t yet understand quite how this is accomplished.
The findings could eventually have practical applications for people with blood cancers and other diseases that are treated with transplants of bone marrow, the site of blood stem cell production. Scientists can make red and white blood cells easily in the laboratory, but bone marrow patients need blood stem cells to constantly replenish their blood supply. Producing these cells, also called hematopoietic stem cells, is much more difficult…. Only about a third of patients who require bone marrow transplants have matching donors. “Basically we cannot offer optimal therapy to two-thirds of patients” [Science News], says Leonard Zon, coauthor of one of the new studies. If researchers can learn how the body stimulates blood stem cell production, they may be able to duplicate the process in the lab, says Zon.
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The Obama administration’s new guidelines for research using human embryonic stem cells have staked out a compromise position, avoiding some controversial areas while still encouraging a large expansion of federally-funded research. The proposed regulations would allow research on stem cells taken from surplus embryos at fertility clinics, where in vitro fertilization generally creates more embryos than will be implanted, and embryos not used are destroyed or kept frozen. The guidelines would allow couples to donate embryos for research, as long as they are not paid and are fully informed of their options [Washington Post].
However, the guidelines do not sanction the use of embryos created specifically for research purposes, an extra step that officials say does not yet have public or political support. The draft guidelines also forbid funding for lines derived through parthenogenesis, a form of asexual reproduction in which an unfertilized egg is developed into an embryo. The International Stem Cell Corporation, a California company, has reported deriving stem cells from parthenotes [Nature News]. Finally, the guidelines prohibit the use of stem cells from human embryos created by cloning, although no such embryos are known to exist.
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A high-powered consortium in the United Kingdom has declared a push to create synthetic blood from embryonic stem cells over the next decade. “In principle, we could provide an unlimited supply of blood in this way” [BBC News], says researcher Marc Turner. Synthetic blood would be guaranteed to be free of viruses like HIV, and could also prevent shortages at blood banks, emergency rooms, and battlefield operations.
While the American biotech company Advanced Cell Technology (ACT) announced last August that they had developed a technique of creating blood from embryonic stem cells, the new UK effort has more significant institutional backing. The multimillion-pound deal involving NHS [National Health Service] Blood and Transplant, the Scottish National Blood Transfusion Service and the Wellcome Trust, the world’s biggest medical research charity, means Britain will take centre stage in the global race to develop blood made from embryonic stem cells [The Independent].
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The controversy surrounding stem cell research might soon be moot, with new research showing that ordinary skin cells can be transformed into an equivalent of embryonic stem cells, which have been the focus of research because of their ability to become any kind of cell in the human body. This is known as a pluripotent state, and the new research, published in two articles in Nature, marks the first time that scientists have turned skin cells into induced pluripotent stem cells or iPS cells—which look and act like embryonic stem cells—without having to use viruses in the process [Reuters].
Scientists have been able to make stem cells from adult cells for more than a year, but relied on the injection of a virus to trigger the transformation of the cell into the embryonic state. These cells could not be used on patients, however, because of the risk they presented of developing cancer. Now, researchers in Britain and Canada have produced the cells by using strands of genetic material, instead of potentially dangerous genetically engineered viruses, to coax skin cells into a state that appears biologically identical to embryonic stem cells [Washington Post].
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The first clinical trial of a therapy based on human embryonic stem cells has received the green light from the FDA, marking a scientific and political milestone for embryonic stem (ES) cell research. The biotech company, Geron Corporation, received approval today for a study that would inject neural stem cells into patients suffering from spinal cord injuries. The study will be mainly a test for safety, but functional improvements, which have been observed in animals trials, may be possible. “For us, it marks the dawn of a new era in medical therapeutics. This approach is one that reaches beyond pills and scalpels to achieve a new level of healing,” Geron Chief Executive Dr. Thomas Okarma said [Reuters].
ES cells are taken from embryos a few days after fertilization and have the potential to differentiate into any type of cell in the body. The undifferentiated cells can’t be used directly, because they can form cancers called teratomas. But they can be used in the lab to generate potentially inexhaustible supplies of all other types of cell[s] that might be needed for repair. The type to be used in the trial are neural stem cells called oligodendrocyte progenitor cells. These support other neurons in the brain and nerves by supplying growth factors and by producing the myelin sheaths that protect neurons from damage [New Scientist]. The FDA will allow Geron to implant these neural stem cells directly into the spinal cords of eight to ten paraplegics. The trials are expected to begin this summer, and may be carried out in multiple medical centers. The patients have not yet been recruited because the injections must take place within two weeks of the spinal cord injury, before scar tissue forms.
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For the first time, scientists have derived and cultured embryonic stem (ES) cells from rats, paving the way for genetically engineered rats that would more accurately model some human diseases than the currently available genetically engineered mice. Two collaborating teams developed a new approach to derive the ES cells, using a new cocktail of molecules to protect their precious pluripotency, the ability to differentiate into any type of cell. “This is a major development in stem cell research because we know that rats are much more closely related to humans than mice in many aspects of biology. The research direction of many labs around the world will change because of the availability of rat ES cells,” says Qilong Ying [Xinhua], who led one of the teams.
ES cells from mice have been available since 1981, and different researchers have created hundreds of different strains of “knock-out” mice—ones raised from ES cells in which certain genes are silenced to make apparent the genes’ functions. With mice, ES cells were grown with a mixture of growth signals to make them divide without differentiating. But transferring the same technique to rats and other mammals proved surprisingly difficult. To the great frustration of researchers, stem cells isolated from rat embryos and cultured with growth signals would quickly lose their pluripotency. The new strategy, reported in two studies in Cell [subscription required], involves growing the ES cells in a mixture of three key molecules that block the signals that normally induce differentiation. “Our discovery was that if you want to maintain cells in the undifferentiated state, you must block signals, not activate them,” says Ying… By repressing differentiation, the researchers could hold the cells in what they call a “ground state,” a blank slate ready to turn into any tissue in the body [Science News].
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The Vatican has issued new ethical guidelines in response to the biomedical advances of the last 20 years, and has come down hard on assisted reproduction technologies and genetic engineering. The document, Dignitas Personae (which translates as “human dignity”), reaffirm the church’s opposition to in vitro fertilization. It also tells Catholics that the church also doesn’t condone “adopting” leftover fertilized embryos from fertility clinics, and frowns upon the genetic testing of embryos before implantation, which could lead to the embryo being discarded. The Vatican says these techniques violate the principles that every human life — even an embryo — is sacred, and that babies should be conceived only through intercourse by a married couple [The New York Times].
These instructions stem from two fundamental theological principles: that life begins at conception and that the origin of human life is the “fruit of marriage.” … The document now makes clear that the morning-after pill, RU-486, and intrauterine devices (IUDs), which either intercept the embryo before implantation or eliminate it after implantation, “fall within the sin of abortion” [Scientific American]. The guidelines may come as a surprise to many Catholics who don’t realize that the church takes such a strict stance on medical technologies like in vitro fertilization that are often seen as routine and beneficial.
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Researchers have found a way to turn cells from human testes into adult stem cells, raising the possibility that men could eventually have spare cells from their own testicles converted into other kinds of tissue for medical treatments and bodily “repairs.” Lead researcher Thomas Skutella harvested spermatogonial cells, which normally mature into sperm, from men and used a series of chemicals to turn them into various cell types…. “We made them into skin, structures of the gut, cartilage, bone, muscle and neurons,” says Skutella [New Scientist].
The achievement is of particular interest because it avoids the ethical quandaries involved in using embryonic stem cells, which require destroying a human embryo. Using testicular cells isn’t the only promising method that avoids embryos; there have been impressive experiments in reprogramming ordinary body cells into stem cells by slipping certain genes into them. The new findings and the reprogrammed cells — which still have technical hurdles — “take some pressure off the stem cell issue,” said White House science adviser Jack Marburger [AP].
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Researchers have found a way to create stem cells from adult liver cells without triggering DNA changes that have caused mutations and tumors in previous studies. Though demonstrated only in mice so far, the result marks another key achievement in the fledgling science of cellular reprogramming. The hope is to create human, embryonic-like stem cells — which can be turned into all the other tissue types of the body — without using eggs or destroying embryos. That freshly derived tissue could then be transplanted into patients to treat various diseases [The Wall Street Journal].
A method of using adult cells to create stem cells was debuted by Japanese researchers in 2006. By using viruses to insert key developmental genes, researchers coaxed human skin cells into an embryonic state, capable of growing into almost any other type of tissue…. But there was a catch: Viruses used to reset the cells tended to fuse with their DNA, leading to unpredictable mutations and cancer. The cells were promising in principle, but couldn’t be used medically [Wired News]. In the new breakthrough, researchers used a different kind of virus to introduce the genes, and found that it didn’t leave behind any damaging genetic code.
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Using embryonic stem cells, researchers have created enough red blood cells to fill several test tubes, in a development that could eventually allow for the mass-production of blood and the end of blood donation drives. “We literally generated whole tubes in the lab, from scratch,” said Robert Lanza, chief science officer at Advanced Cell Technologies [Wired News].
The breakthrough raises the prospect of mass-producing supplies of the “universal donor” blood type O-negative, which is prized because it can be safely transfused into any patient, whatever their blood group. This type of blood is in short supply – around 8% of Caucasians have it, and just 0.3% of Asians [New Scientist]. Experts say the method would also help keep pathogens like HIV out of the blood supply, as blood banks would no longer have to screen the blood from thousands of donors.
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