Anti-IGKV2-40 antibodies are used in the immunodetection of the protein immunoglobulin kappa variable 2-40. In humans, the canonical protein has a reported length of 121 amino acid residues and a mass of 13.3 kDa. Its subcellular localization is in the cell membrane and is secreted. IGKV2-40 is known to be involved with adaptive immune responses.