Coordinated Vγand Vδgene segment rearrangements in human T cell receptor γ/δ+lymphocytes

摘要

AbstractMonoclonal antibodies (mAb) were used to characterize a panel (n= 46) of T cell receptor (TcR) γ/δ+T cell clones. Three of these antibodies have been described to react with specific variable region‐encoded protein products and can therefore be used to detect functional gene rearrangements. The majority of peripheral blood‐derived clones (43 out of 45) expressed the epitopes recognized by mAb BB3, encoded by the Vδ2 gene segment and mAb TiγA, encoded by the Vγ9 gene segment. These clones lacked the antigenic determinant recognized by mAb δ‐TCS‐1, encoded by the Vδ1 gene segment. The other two peripheral blood‐derived clones and an ascites‐derived clone were TiγA‐, BB3‐and δ‐TCS‐1+. Biochemical analysis revealed that all TiγA+, BB3+T cell clones expressed the disulfide‐linked form of the receptor. The two peripheral blood‐derived δ‐TCS‐1+T cell clones expressed the nondisulfide‐linked form whereas the ascites‐derived δ‐TCS‐1+clone, AK119 expressed the disulfide‐linked form of the TcRγ/δ heterodimer. This indicates that Vδ1‐encoded δ chains can be associated either with a Cγ1‐ or a Cγ2‐encoded γ chain. The preferential use of certain Vγand Vδgene segments suggests the existence of a limited combinatorial diversity in TcRγ/δ heterodimers,i.e.TiγA+(Vγ9), BB3+(Vδ2) and δ‐TCS‐1‐disulfide‐linked heterodi