Anti-CD66d antibodies enable researchers to detect and measure the CD66d antigen in biological samples. This target is a reported synonym of the CEACAM3 gene, which encodes CEA cell adhesion molecule 3. This protein is known to function in signal transduction pathways, among other biological roles. The human version of CD66d has a canonical amino acid length of 252 residues and a protein mass of 27.1 kilodaltons, although 3 isoforms have been identified. It is reported to be localized in the membrane of cells and notably expressed in the rectum, lymph node, colon, bone marrow, and appendix. This target antigen may also be known as CEA. ELISA, Western Blot, and Immunohistochemistry are common applications for CD66d antibodies.