Xenograft

Xenograft refers to transplantation of cells, tissues, or organs from one species into another, most commonly involving implantation of human tumour cells or tissues into immunocompromised mice to create preclinical cancer models. These models enable evaluation of tumour growth behaviour and therapeutic responses in vivo, supporting translational research bridging laboratory findings and clinical application. Xenograft models require immunodeficient recipients lacking functional immune systems that would otherwise reject foreign tissues.

The biopharmaceutical industry relies heavily on xenograft models throughout oncology drug development. Cell line-derived xenografts use established cancer cell lines providing reproducible tumour growth enabling efficacy testing, though limited tumour heterogeneity and altered biology from prolonged culture reduce clinical predictivity. Patient-derived xenografts implant fresh tumour samples maintaining heterogeneity and molecular characteristics more closely resembling patient disease, offering improved predictive value. Humanised xenograft models combine human tumours with human immune systems enabling immunotherapy evaluation. Applications include efficacy assessment, pharmacokinetic-pharmacodynamic studies, biomarker validation, and combination therapy testing. Limitations include artificial microenvironment lacking human stroma and vasculature, and species differences affecting drug metabolism. As patient-derived models improve and alternative models including organoids emerge, xenograft technology continues providing a valuable preclinical platform.