By Lisa Seachrist
BETHESDA, Md. ¿ The process for implementing federal funding of research using pluripotent embryonic stem (ES) cells continued to move forward, as a National Institutes of Health (NIH) panel began drafting guidelines and oversight mechanisms for regulating the research.
NIH Director Harold Varmus set the process in motion in January, when he announced that the Department of Health and Human Services¿ (HHS) general counsel, Harriet Rabb, had determined that there were no prohibitions to such funding. In light of the terrific therapeutic potential of these cells, Varmus said, he intended to pursue federal support of the research.
The working group to advise the Advisory Committee to the Director (ACD) created the framework under which NIH would fund the research. Varmus intends publish the draft guidelines for public comment, and then present them to the full ACD.
¿By the end of the day, we would like to have guidelines that could be published in the Federal Register,¿ Varmus said. ¿I¿d like there to be consideration of those criteria, under which NIH can fund this research. I feel very strongly about the matter of oversight.¿
Panel Opts To Follow 1995 Ban
The dilemma surrounding ES cells comes not from the cells themselves, which are capable of becoming any differentiated cell in the body, but are incapable of creating a human being when implanted into a woman¿s womb. Instead the problem comes from the source of the cells: either aborted fetuses, or ¿spare¿ embryos left over from in vitro fertilization procedures.
There are federal laws on the books permitting the research on cells derived from aborted fetuses. However, ever since 1995, the NIH has been banned from funding research that creates a human embryo or embryos for its purposes, or research in which a human embryo or embryos are destroyed, discarded or knowingly subjected to risk of injury or death.
The ban has been accomplished by way of an appropriations rider that is annually voted into effect by Congress.
Because of the opposition in Congress to human embryo research, Varmus needed to establish that ES cells are not embryos per se, and that the NIH wouldn¿t fund such research. Varmus, instead, wants to support research that could lead to new tissue therapies for diseases ranging from spinal cord injuries to diabetes to Alzheimer¿s disease.
Shirley Tilghman, professor of molecular biology at Princeton University and co-chair of the working group, said goals of the day were to provide the framework for ethically administering such research, not to determine whether the research should be funded.
¿Our charge is clearly to [determine how], if this research is going to be conducted with federal funds, we can ensure that it is done in an ethical manner,¿ Tilghman said.
The working group chose to follow the appropriations rider and ban the derivation of ES cells from human pre-implantation embryos. In addition, the panel agreed that federal funds shouldn¿t fund research which transfers ES cells into human or non-human blastocysts to create human or human-animal chimeric embryos.
NIH won¿t fund research using ES cells to create a cloned human being, nor will it fund research using such cells, if local laws governing the researchers prohibit such research. The group also established that buying and selling of gametes, embryos, fetal tissue or the ES cells shouldn¿t be permitted with federal funds.
For research that is not specifically ineligible for federal funds, the working group established that very clear informed-consent measures are necessary. The committee referred to the informed-consent requirements for fetal tissue transplants, and called for any decision to donate embryos for research that would create ES cells to be made separately from the decision to undergo in vitro fertilization procedures.
¿Because most of these donations are going to occur once a couple has had successful pregnancy and the embryos are truly left over, the decision will necessarily be temporally separated,¿ said panel member Arthur Haney, professor of reproductive endocrinology and infertility at Duke University in Durham, N.C.
That informed consent for tissue donors will need to identify what makes pluripotent stem cells unique ¿ for example, the fact that the cells will survive for a very long time in culture, and are self-renewing. The informed consent must explicitly state the extent to which privacy and confidentiality will be maintained, as well as assuring donors that the cells will never be implanted into a woman¿s womb.
Many Members Of Congress Still Opposed
Haney argued that all parties involved in the creation of the embryos, including gametes donors, should give consent. The panel, however, did not reach consensus on that point.
All research that will use federal monies to conduct research on these types of cells will be subject to review by a stem-cell research committee. The panel recommends the NIH build in a sunset clause, calling for a three-year limit to the committee¿s operations.
Despite the work on these guidelines, it is quite possible that Congress will attempt to prevent federal funding of this research. More than 70 members of Congress have objected to Varmus¿ plan, saying it is in violation of both the letter and the spirit of the law.
Maggie Wynne, a representative of the ¿pro-life¿ caucus in the House of Representatives, told the panel that the caucus considers Varmus¿ definition of a human embryo as a ¿carefully worded effort to transgress the law.¿ Under the HHS opinion, ES cells are not embryos, because they can¿t be implanted into a womb and do not result in a human being.
Wynne, however, said there is ¿no need to require that [ES cells] develop into a human being, because it already is a human being.¿
Richard Doerflinger, with the National Council of Catholic Bishops, agreed, saying that such a definition encourages researchers to engineer defective embryos in order to conduct research.