Human-animal chimeras for autologous organ transplantation: technological advances and future perspectives

Organ transplantation is the most promising curation for end-stage organ disease. However, the donor organ shortage has become a global problem that has limited the development of organ transplantation. Human-animal chimeras provide the ability to produce human organs in other species using autologous stem cells [e.g., induced pluripotent stem cells (iPSCs) or adult stem cells], which would be patient-specific and immune-matched for transplantation. Due to the potential application prospect of interspecies chimeras in basic and translational research, this technology has attracted much interest. This review focuses primarily on technological advances, including options of donor stem cell types and gene editing in donor cells and host animals, in addition to perspectives on human-animal chimeras in clinical and basic research.