The Vbeta13.2 TCR is a variant of the TCR beta chain. It belongs to Ig superfamily and is expressed by a subset of peripheral blood T cells and some T cell clones. Vbeta expression in humans and mice has been used to study the effects of superantigens and also to examine the repertoires of T cells involved in inflammatory and autoimmune disease. It is reported that Vbeta13.2 TCRs possess very unusually long beta-chain CDR3 regions and are expressed on CTL specific for the immunodominant human HLA-B8–restricted HIV-1 nef epitope, FLKEKGGL (FL8). CTL expressing V beta13.2 TCRs tolerate naturally arising viral variants in the FL8 epitope that escape recognition by other CTL. The clone H132 recognizes the Vbeta13.2 allele product but does not react with the Vbeta13.1, 13.3, 13.5 and 13.6 allele products of the Vbeta13 subfamily.