ASH Endorses Ethical Guidelines for Human Embryonic Stem Cell Research

Human embryonic stem (ES) cells are derived from early embryos and are capable of differentiating into all tissues. Although they are excellent tools for research and have broad therapeutic promise, their procurement, manipulation, and use raise major ethical issues.

The International Society of Stem Cell Research (ISSCR) accepted the challenge of analyzing these concerns and of writing guidelines for the conduct of human ES cell research. Their thoughtful document was reviewed by ASH’s Scientific Committee on Stem Cells and its Committee on Government Affairs, and has been formally endorsed by the Executive Committee.

Human ES cell research may lead to novel therapies for genetic, malignant, and degenerative disorders. Theoretically, one could construct replacement cells for blood, skin, pancreas, or other tissues. Also, studies of ES cell lines derived from diseased embryos could provide new insights into the pathophysiology of Fanconi anemia, thalassemia, sickle cell disease, and other genetic disorders, or be used to test drug therapies. This promise has led to both excitement and unrealistic expectations since many scientific obstacles remain. For example, we need methods to ensure that the mature cells generated in vitro have normal function and retain genetic integrity before these applications are feasible.

Furthermore, there are major ethical obstacles to human ES cell research since ES cells derive from the inner cell mass of blastocysts (an early embryo). If left in situ, adjacent to the trophoectoderm, these cells could implant in the uterus and develop into a fetus and child. However, when removed at this early stage, they lose this fate and if transplanted can only give rise to teratomas (a disorganized differentiating cell body). For an investigator, it is often difficult to navigate the hype, scientific reality, political reality, and ethical issues implicit in human ES cell research. The goal of the ISSCR guidelines was to clearly articulate principles and rules of behavior and thus to facilitate the ethical conduct of this research.

The guidelines specifically state that scientific trainees and technical staff with conscientious objection to human ES cell research should not be required to participate in the research or cell procurement. They prohibit human reproductive cloning (defined as seeking to establish a pregnancy and birth by the transfer into the uterus of human embryos derived from nuclear transfer or nuclear reprogramming). In addition, they prohibit the culture of human embryos beyond 14 days or the time of formation of the primitive embryonic streak, the step that triggers organogenesis.

One important strength of the guidelines is the authors’ insistence that all terms are precise and accurate. Because of this, the position and intent of the document are clear. The accompanying glossary of terms is written in simple, accurate language. This and the answers to frequently asked questions may also be helpful to ASH members.

The ISSCR guidelines are comprehensive. They cover aspects of human ES cell research ranging from establishment of human ES cell lines, the distribution and sharing of materials among scientists, the need for informed consent at the time of donation and not afterwards, and the understanding that consent must be voluntary, explicit, and free of financial inducement or other coercion to suggested processes for the institutional oversight of this research.

Sample consent forms for the donation of oocytes, embryos, somatic cells, and sperm are provided. To facilitate the exchange of research materials among scientists, sample material transfer agreements are also provided.

The ISSCR guidelines were written by scientists, lawyers, and ethicists from 14 countries. It is not surprising that ASH members had prominent roles. George Daley, MD, PhD (Children’s Hospital, Boston), chaired the ISSCR guidelines committee and authored the accompanying manuscript in Science¹  that discusses the differences between these guidelines and recent documents by the U.S. National Academy of Sciences and the California Institute for Regenerative Medicine. The current president, immediate past president, and vice president of the ISSCR are ASH members.

It is likely that the ISSCR guidelines will be an excellent resource for ASH members. It should be a useful document for investigators and for institutions involved in the oversight of human ES cell research as it is comprehensive and pragmatic. It is also excellent reading for a concerned practitioner who wants a clear, conceptual understanding of the ethical challenges of human ES cell research to share with family, friends, or patients.