Anti-pERp1 antibodies enable researchers to detect and measure the pERp1 antigen in biological samples. This target is a reported synonym of the MZB1 gene, which encodes marginal zone B and B1 cell specific protein. This protein is known to function in the apoptotic pathway and the regulation of cell proliferation, among other biological roles. The human version of pERp1 has a canonical amino acid length of 189 residues and a protein mass of 20.7 kilodaltons, although 5 isoforms have been identified. It is reported to be localized in the ER, cytoplasm, and is secreted of cells and notably expressed in many tissues, such as the bone marrow, tonsil, and appendix. Other names for this target antigen include MEDA-7 and PACAP.