Used in immunological research to study cell adhesion and signaling mechanisms in non-human primate models. Serves as a critical reagent in developing and testing monoclonal antibodies targeting CEACAM5, which is overexpressed in certain cancers like colorectal carcinoma. Enables cross-reactivity studies with human therapeutics due to high homology between primate and human CEACAM5. Facilitates preclinical evaluation of drug candidates, particularly in oncology and inflammation, using cynomolgus or rhesus macaque models. The His tag allows for easy detection and purification in experimental assays.