Harvard Joins New U.S. Push In Stem Cells [WSJ]
By SYLVIA PAGÁN WESTPHAL
June 7, 2006; Page B1
Researchers at Harvard University said they are beginning experiments to clone human embryos for making stem cells, a move that lends clout to renewed U.S. efforts to master the technology.
The announcement marked the culmination of lengthy preparations designed to keep the effort within the ethical and legal boundaries of what is considered to be one of the most controversial areas of medical research.
It is illegal to use federal money for research in which human embryos are harmed. Harvard says its effort will be privately funded.
Harvard's effort mirrors that of other U.S.-based researchers who have also announced recent cloning initiatives in the wake of a major scientific scandal in South Korea, where researchers falsely claimed they had created stem cells from cloned embryos. The Korean debacle has renewed U.S. hopes that the country will regain prominence in world-wide efforts to master the difficult technology.
Douglas Melton, of the Harvard Stem Cell Institute, hopes to make stem cells from cloned human embryos.
In cloning, a person's cell is introduced into an egg whose own DNA has been stripped. Inside the egg, the cell starts to divide and form an embryo that is genetically identical to the person who donated the cell. At its earliest stages -- when it's only a few dozen cells in size -- the embryo contains special cells known as "stem cells," which have the unique ability to become all the tissues in the body.
The Harvard experiments aim to take cells from patients with diseases such as diabetes and neurodegenerative disorders to create genetically identical embryos. Because stem cells from those embryos carry the genetic defects of people with the diseases, the scientists hope to study the cells to understand how to repair the problems.
Harvard's announcement comes after scientists at the University of California in San Francisco and closely held Advanced Cell Technology in Worcester, Mass., said in May they would also be resuming efforts to clone human embryos for research purposes.
"The science is moving forward in the face of significant hardship," said Arnold Kriegstein, director of the UCSF Institute for Regeneration Medicine, which has started to work on the technology. Scientists in the United Kingdom and Sweden are also working on creating stem cells from cloned embryos.
Richard Doerflinger, deputy director of pro-life activities at the U.S. Conference of Catholic Bishops, said the Harvard effort "will likely be a waste of money and a waste of lives....People think this is some kind of miracle cure around the corner, but for now they'll be exploiting women and killing embryos."
In the type of research planned at Harvard, the embryos created via cloning would be destroyed at an early stage and their stem cells would be extracted. In the laboratory, the scientists would hope to coax the cells into becoming specialized tissue cells, such as insulin-producing pancreatic cells.
One of the Harvard researchers, George Daley, wants to make cloned embryos from patients with blood diseases and derive stem cells from the embryos so he can repair the defect in the laboratory. The cells could then be placed back -- without fear of rejection -- in those people. In similar experiments done in mice, Dr. Daley's team has been able to treat a blood disease using this approach.
But any medical applications of the technology are still many years away. After yesterday's announcement, the Harvard researchers will attempt to take the very first step of the process: getting a human cloned embryo to develop to the stage where stem cells can be extracted from it. It's a goal that has so far proved elusive for several teams around the world.
Harvard said millions of dollars were being devoted to the cloning effort, but declined to be specific. The school said its funding sources include the Howard Hughes Medical Institute, of Chevy Chase, Md.; Boston's Children's Hospital; the New York Stem Cell Foundation, and private individuals.
Douglas Melton, co-director of the Harvard Stem Cell Institute, whose team will be working with cells donated by diabetic patients, maintains a separate facility at Harvard for work he has been doing with human embryonic stem cells derived from IVF embryos. This is where some of the new cloning experiments will take place as well.
Dr. Daley said his laboratory has a separate room where "every single pipette, Petri dish and reagent bottle" has been bought with private money and is marked with a sticker. "We have careful administrative and financial accounting methods in place to insure that none of the experiments that involve [cloning] use any materials purchased with federal funds." At UCSF, the cloning work is also conducted in facilities that receive no federal funds, a spokeswoman said.
The Harvard experiments were approved after a lengthy review by eight different boards and committees at five different institutions involved in the work. These included two Boston area hospitals, a local IVF clinic and Columbia University, where cells from diabetic patients will be grown for the Harvard experiments.
According to Leonard Zon, director of the stem-cell program at Children's Hospital, the two-year process not only involved an extensive ethics review but also consideration of legal and intellectual-property issues. One of the issues was the risk to women from the hormone treatments used in the process of egg donation. According to Harvard researcher Kevin Eggan, it was decided that women would be given hormone doses tailored toward not producing too many eggs, in order to minimize their risk of side effects.
Massachusetts, where Harvard is located, passed a law last year making it illegal to pay for eggs for stem-cell research. For the Harvard experiments, two of the three teams will procure eggs donated by women. At Dr. Daley's laboratory, as well as the UCSF facility, scientists will instead use leftover eggs from failed in vitro fertilization treatments.
Either strategy has pitfalls. Robert Lanza, vice president of research at Advanced Cell Technology, says the company has, since December 2005, placed "over 100 ads" looking for egg donors. Initially there were many replies, but as women realized the discomfort and risks involved in hormone treatments, the numbers have dwindled to two or three potential candidates. "We don't have a single egg at this point," he says.
On the other hand, eggs from failed IVF treatments are plentiful but their ability to form embryos might be compromised. "It might not even be possible" to use them, says Dr. Lanza. He says the company's experience as well as published research suggests that eggs for cloning should be used within hours of obtaining them. Eggs from failed IVF treatments tend to be one to two days old, he says.
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