Anti-TRBV9 antibodies are used in the immunodetection of the protein T cell receptor beta variable 9. In humans, the canonical protein has a reported length of 114 amino acid residues and a mass of 12.6 kDa. Its subcellular localization is in the cell membrane. TRBV9 is known to be involved with adaptive immune responses and receptor-mediated signaling pathways. Post-translational modifications have been described, including glycosylation.