Illustrative image for Actionable Ethics Oversight of Human Animal Chimera Research

Actionable Ethics Oversight of Human-Animal Chimera Research

Principal Investigators: Josephine Johnston, Karen Maschke, Insoo Hyun (Case Western Reserve University)

Co-Investigator: Carolyn Neuhaus

Funder: National Institutes of Health

With recent scientific advances, investigators are better equipped than ever to insert human cells into animals for research purposes. Research animals that contain human cells are called human-animal chimeras. Many people hope that research with chimeras will yield enormous benefits, including more accurate models of human disease, inexpensive sources of human eggs and embryos for research, and sources of tissues and organs suitable for transplantation into humans.

But there are several ethical concerns about this type of research. A core concern is whether inserting large amounts of human neurons and other cells in the brains of nonhuman animals will “humanize” those animals. What does “humanization” mean, and how is it measured or detected? And when is it and when is it not ethically problematic?

This project aims to understand what is motivating so-called humanization concerns and to find a reasonable path forward that can be applied in research oversight. Other goals include identifying the significance of these humanization concerns with respect to animal welfare and use, identifying the strengths and challenges of existing oversight approaches to  chimera research, and developing actionable recommendations and educational materials for enhancing oversight of human-animal chimera research.