Provided below are ELISA kits targeting tissue specific transplantation antigen P35B, a human protein encoded by TSTA3. This protein is 321 amino acids long, with a mass of 35.9 kDa, and is a member of the NAD(P)-dependent epimerase/dehydratase family, Fucose synthase subfamily. Other alias names for this protein include: 3-5 epimerase/4-reductase, GDP-4-keto-6-deoxy-D-mannose epimerase-reductase, GDP-4-keto-6-deoxy-D-mannose-3,5-epimerase-4-reductase, short chain dehydrogenase/reductase family 4E member 1, and testis tissue sperm-binding protein Li 45a.