Anti-Sg II antibodies enable researchers to detect and measure the Sg II antigen in biological samples. This target is a reported synonym of the SEMG2 gene, which encodes semenogelin 2. This protein is known to participate in the formation of a gel matrix (sperm coagulum) entrapping the accessory gland secretions and ejaculated spermatozoa. The human version of Sg II has a canonical amino acid length of 582 residues and a protein mass of 65.4 kilodaltons. It is reported to be a secreted protein that is notably expressed in the seminal vesicle. This target antigen may also be known as semenogelin II.