Anti-BIRC4 antibodies are protein reagents that detect specific antigens. The BIRC4 antigen is another term for the human protein X-linked inhibitor of apoptosis, encoded by the XIAP gene. The protein is reported to be a multi-functional protein, which regulates not only caspases and apoptosis, but also modulates inflammatory signaling and immunity, copper homeostasis, mitogenic kinase signaling, cell proliferation, as well as cell invasion and metastasis. Canonically, it has an amino acid length of 497 residues and a mass of 56.7 kilodaltons. Its subcellular localization is in the nucleus and cytoplasm and it is reported to be expressed in colonic crypts. The BIRC4 protein is a member of the IAP protein family. Other alias names for BIRC4 include API3 and IAP-3. Some BIRC4 antibodies may have been used in research and have associated citations. Western Blot is a widely used application for these antibodies. ELISA and Immunohistochemistry are also common applications.