Anti-SPESP1 antibodies are used in the immunodetection of the protein sperm equatorial segment protein 1. In humans, the canonical protein has a reported length of 350 amino acid residues and a mass of 38.9 kDa. Its subcellular localization is in the cytoplasmic vesicles. It is reported to be highly expressed in the testis, where it is localized in the acrosome of postmeiotic stages of spermiogenesis (round and elongating spermatids and in ejaculated spermatozoa). A member of the SPESP1 protein family, SPESP1 is known to be involved in fertilization ability of sperm. Post-translational modifications have been described, including N-glycosylation. Synonyms for this target antigen include equatorial segment protein and glycosylated 38 kDa sperm protein C-7/8. SPESP1 gene orthologs have been reported in the mouse, rat, bovine and chimpanzee species. Western Blot is a widely used application for the SPESP1 antibodies listed below. In addition, ELISA is also a common application.