Anti-CEACAM3 antibodies are used in the immunodetection of the protein CEA cell adhesion molecule 3. In humans, the canonical protein has a reported length of 252 amino acid residues and a mass of 27.1 kDa. Its subcellular localization is in the membrane. Up to 3 different isoforms have been reported for this protein. It is notably expressed in the rectum, lymph node, colon, bone marrow, and appendix. A member of the CEA protein family, CEACAM3 is known to be involved with signal transduction pathways. Post-translational modifications have been described, including phosphorylation and glycosylation. Synonyms for this target antigen include CEA, W264, W282, carcinoembryonic antigen-related cell adhesion molecule 3, and CD66D. CEACAM3 gene orthologs have been reported in the mouse and chimpanzee species. Over 100 citations in the literature describe the use of CEACAM3 antibodies in research. Immunohistochemistry is a widely used application for these antibodies. ELISA and Western Blot are also common applications.