xenogeneic

Xenogeneic is an adjective describing tissues, cells, or organs obtained from a species different from the one into which they are used. The term comes from Greek xenos, meaning stranger, and genes or origin, and it is used in biology and medicine to describe cross-species relationships or applications.

In biology and medicine, xenogeneic materials or xenografts originate in one species and are used in another. This includes animal tissues or organs used as implants, as well as decellularized or synthetic scaffolds derived from animal sources. Xenotransplantation specifically denotes the transplantation of organs, tissues, or cells across species boundaries and is distinct from autologous, allogeneic, or syngeneic transplantation.

A central challenge of xenogeneic approaches is immune rejection. Hyperacute, acute vascular, and cellular rejection can limit graft survival. Strategies to mitigate rejection include genetic modification of donor animals to remove or alter antigenic epitopes, improved immunosuppression, and tolerance-induction approaches. A major safety concern is xenozoonosis, the transmission of animal pathogens to humans, which drives rigorous screening, containment, and regulatory oversight.

Xenogeneic materials are widely used as scaffolds and biologics in regenerative medicine, dentistry, and orthopedics. Xenotransplantation has progressed from theory and preclinical work toward clinical research, with advances in gene-edited donor animals and improved immunosuppression expanding feasibility. Ethical, regulatory, and public-health considerations continue to shape development and implementation.