Xenogen

Xenogen is a term used in biology and biotechnology with several related but distinct uses. In a broad sense, it describes biological material or processes of foreign origin relative to a given host species, particularly materials derived from different species. In practice, more precise terminology—such as xenogeneic, xenograft, or xenogenesis—is often used to specify cross-species transplantation or genetic exchange. The element xeno- comes from Greek for "foreign" and -gen from Greek for "origin" or "produced by."

Historically, Xenogen also referred to a biotechnology company known for in vivo imaging technologies for small animals. Xenogen Corporation produced imaging systems that enabled visualization of biological processes in living animals using bioluminescence and fluorescence, often in conjunction with software such as Living Image. The company was acquired by Caliper Life Sciences in 2006, and Caliper Life Sciences itself was acquired by PerkinElmer in 2011. In current practice, the Xenogen name is largely historical, with the imaging technologies continuing under PerkinElmer’s portfolio and integrated with related products such as IVIS systems.

Xenogen-related terms are generally avoided in formal modern usage in favor of more specific descriptors like xenogeneic, xenograft, or xenogenesis, to reduce ambiguity about cross-species origin or genetic material. See also xenogeneic, xenograft, and xenogenesis for related concepts.