A MYCOBACTERIAL HEAT-SHOCK PROTEIN-RESPONSIVE GAMMA-DELTA T-CELL CLONE ALSO RESPONDS TO THE HOMOLOGOUS HUMAN HEAT-SHOCK PROTEIN - A POSSIBLE LINK BETWEEN INFECTION AND AUTOIMMUNITY

Prokaryotic and eukaryotic cells respond to a variety of stress conditions by increasing the synthesis of a family of proteins collectively known as heat-shock proteins (HSP). One of these, a 65-kDa HSP that is highly conserved in many bacteria, is a major target of the immune response to mycobacteria. A gamma-delta-T cell clone from a healthy donor that recognizes not only the 65-kDa mycobacterial HSP but also the recombinant human homologue of this HSP protein was raised. Like alpha-beta-T cell clones, which recognize mycobacterial HSP, the clone requires antigen-presenting cells for antigen-induced proliferation and can also be directly activated via receptor cross-linking through CD3 or the delta-chain of the gamma-delta-T cell receptor. These data suggest that the induction of a gamma-delta-T cell response by bacterial antigens could lead to the expansion of cells that respond to autologous proteins and, therefore, may result in the development of autoimmunity.