Anti-SPAM1 antibodies are used in the immunodetection of the protein sperm adhesion molecule 1. In humans, the canonical protein has a reported length of 509 amino acid residues and a mass of 57.8 kDa. Its subcellular localization is in the cell membrane. Up to 2 different isoforms have been reported for this protein. It is notably expressed in the testis. A member of the Glycosyl hydrolase 56 protein family, SPAM1 is known to be involved in sperm-egg adhesion. Post-translational modifications have been described, including N-glycosylation. Synonyms for this target antigen include HYA1, HYAL1, HYAL3, HYAL5, PH-20, PH20, SPAG15, and HEL-S-96n.