The National Institutes of Health on Thursday announced that it will fund human-animal chimera research – but with restrictions.
Last year the NIH released notice NOT-OD-15-158, which effectively stalled all new NIH-funded research in which human stem cells were being introduced into nonhuman vertebrate embryos. While human cells have been routinely inserted into animals (such as mice) to study tumor development, the use of human stem cells in the early development of nonhuman vertebrate embryos is relatively new and raises a number of concerns. The dispute centers on the ethics of generating these animals and the extent to which these engineered creatures would be human.
In response to the criticisms raised by opponents, the NIH now is proposing to amend sections IV and V of its guidelines for human stem-cell research. Additionally, the NIH is proposing the creation of a steering committee to provide programmatic oversight and to review all human-animal chimera research projects.
Outlined in notice NOT-OD-16-128, released Thursday, the new committee will conduct an internal review on new human-chimera research proposals and provide input on:
(1) the characteristics of the human cells to be introduced (including potency and any modifications of those cells);
(2) characteristics of the recipient animal (e.g., species, stage of development, and any modifications that affect location or function of human cells);
(3) other data relevant to the likely effects on the animal (e.g., changes in cognition, behavior, or physical appearance);
(4) planned monitoring (including animal welfare assessments); and
(5) any staging of proposed research (e.g., assessing the outcome of a particular experiment before conducting a further experiment).
This review will occur in addition to the normal peer-review conducted on all NIH grant proposals.
While the proposed policy reopens the possibilities of human–animal chimera research on most nonhuman vertebrates, certain conditions and animals would remain prohibited. The policy would ban the introduction of human stem cells into nonhuman primate embryos as well as prohibit the breeding of animals that may produce human gametes.
The NIH has taken a huge step in ensuring the continued innovation of stem-cell research. While some may argue that halting chimera research a year ago was not in the interest of the research community, providing a thoughtful and methodical response to this emerging and controversial research area is what should be expected of an agency committed to pushing the frontiers of biomedical research.
The proposed changes are open for comment until Sept. 4.