RECOGNITION BY HUMAN V-GAMMA-9/V-DELTA-2 T-CELLS OF A GROEL HOMOLOG ON DAUDI-BURKITT LYMPHOMA-CELLS

All human γδ T cells coexpressing the products of the variable (V) region T cell receptor (TCR) gene segments Vγ9 and V δ2 recognize antigens from some mycobacterial extracts and Daudi cells. Exogenous and endogenous ligands on the cell surface, homologous to the groEL heat shock family, induced reactivities that resembled superantigen responses in this major subset of human peripheral blood γδ T cells. Stimulation of human Vγ9/Vδ2 T cells is not restricted by human leukocyte antigens (HLA), including nonpolymorphic β2-microglobulin (β2M)-associated class Ib molecules. These data may be important for understanding the role of γδ T cells in autoimmunity and in responses to microorganisms and tumors.