A Subset of Vδ1+ T Cells Proliferates in Response to Epstein-Barr Virus-Transformed B Cell Lines In Vitro

It has previously been shown that murine tissue derived T-cells expressing the γδ T-cell receptor can respond to autologous (stressed) cells implying the recognition of an autoantigen. Here we report that a large proportion of human synovial tissue and peripheral blood derived Vδ1+γδ T-cell clones proliferate in response to stimulation with autologous and allogeneic EBV-transformed B-lymphobiastoid cell lines (LCL). In contrast, Vδ1-γ/δ and α/β TCR+ T-cell clones isolated from the same tissue samples did not display proliferation towards the LCL. The proliferative response of these Vδ1+ clones was dependent on contact between responder and stimulator cells and could be blocked by a MoAb to LFA-1 and by antibodies to the γδ TCR/CD3 complex. Because the responses of these clones to LCL cells appear to be independent of the γ-chain co-expressed with the Vδ1-chain these resemble a superantigen response. The capacity of this subset of Vδ1+ T-cell clones to proliferate after stimulation with LCL may imply the recognition of an endogenous epitope. Moreover, since so far we have been able to isolate only LCL reactive γδ T-cell clones from synovial tissue and peripheral blood of reactive arthritis patients and not from peripheral blood of healthy individuals, tbe frequency of such ‘autoreactive’γδ cells may be higher in these patients.