Anti-NXPE4 antibodies are used in the immunodetection of the protein neurexophilin and PC-esterase domain family member 4. In humans, the canonical protein has a reported length of 544 amino acid residues and a mass of 62.3 kDa. It has been described to be a secreted protein. Up to 2 different isoforms have been reported for this protein. It is notably expressed in the testis, salivary gland, rectum, and colon. It is a member of the NXPE protein family. Post-translational modifications have been described, including glycosylation. Synonyms for this target antigen include FAM55D, NXPE family member 4, family with sequence similarity 55, member D, protein FAM55D, and C11orf33. NXPE4 gene orthologs have been reported in the mouse, rat and chimpanzee species. Western Blot, Immunofluorescence, and Immunohistochemistry are common applications for NXPE4 antibodies.