Anti-B(p51B) antibodies enable researchers to detect and measure the B(p51B) antigen in biological samples. This target is a reported synonym of the TP63 gene, which encodes tumor protein p63. This protein is known to function in the apoptotic pathway and chromatin remodeling, among other biological roles. The human version of B(p51B) has a canonical amino acid length of 680 residues and a protein mass of 76.8 kilodaltons, although 12 isoforms have been identified. It is reported to be localized in the nucleus of cells and notably expressed in many tissues, such as the breast and bronchus. Other names for this target antigen include AIS, B(p51A), and B(p51B).