Anti-MRXSF antibodies enable researchers to detect and measure the MRXSF antigen in biological samples. This target is a reported synonym of the AP1S2 gene, which encodes adaptor related protein complex 1 subunit sigma 2. This protein is known to function in intracellular protein transport and vesicle-mediated transport, among other biological roles. The human version of MRXSF has a canonical amino acid length of 157 residues and a protein mass of 18.6 kilodaltons, although 2 isoforms have been identified. It is reported to be localized in the cytoplasmic vesicles, Golgi, and membrane of cells and notably expressed in many tissues, such as the fallopian tube and testis. Other names for this target antigen include DC22, MRX59, and MRXS21.