Anti-CDP138 antibodies enable researchers to detect and measure the CDP138 antigen in biological samples. This target is a reported synonym of the C2CD5 gene, which encodes C2 calcium dependent domain containing 5. This protein is known to function in insulin signaling pathways and carbohydrate metabolism and homeostasis, among other biological roles. The human version of CDP138 has a canonical amino acid length of 1000 residues and a protein mass of 110.4 kilodaltons, although 5 isoforms have been identified. It is reported to be localized in the cell membrane, cytoplasmic vesicles, and cytoplasm of cells and widely expressed in many tissue types.