title: The recombinant 65-kD heat shock protein of Mycobacterium bovis Bacillus Calmette-Guerin/M. tuberculosis is a target molecule for CD4+ cytotoxic T lymphocytes that lyse human monocytes.
abstract: Since little is known about Tc cells in the human immune response to intracellular parasites, we have studied the role of Tc cells in response to M. bovis Bacillus Calmette-Guerin (BCG). Donors whose PBMC responded to BCG, purified protein derivative (PPD), and the recombinant 65-kD heat shock protein (HSP) of BCG generated BCG/PPD-specific CD4+ effector T lymphocytes that lysed PPD as well as recombinant 65-kD-pulsed monocytes. Nonpulsed or irrelevant antigen-pulsed target cells were lysed to a much lower but still significant extent. PPD-stimulated effector lymphocytes of a recombinant 65-kD nonresponder lysed PPD but not recombinant 65-kD-pulsed monocytes. Recombinant 65-kD-educated effector lymphocytes lysed both recombinant 65-kD- and PPD-pulsed monocytes. In addition, these effector cells efficiently lysed nonpulsed target cells. These results demonstrate that in recombinant 65-kD responders, the recombinant 65-kD HSP of BCG is an immunodominant target as well as a triggering molecule for BCG/PPD-specific CD4+ cytotoxic T cells that lyse autologous monocytes. The implications of these findings with respect to the role of the 65-kD HSP in autoimmunity are discussed.
mesh_terms: D001327:Autoimmune Diseases / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D003602:Cytotoxicity, Immunologic; D006360:Heat-Shock Proteins / Q000276:immunology*; D006801:Humans; D066298:In Vitro Techniques; D008213:Lymphocyte Activation; D009000:Monocytes / Q000276:immunology*; D009163:Mycobacterium bovis / Q000276:immunology*; D009166:Mycobacterium leprae / Q000276:immunology; D009169:Mycobacterium tuberculosis / Q000276:immunology*; D011994:Recombinant Proteins / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*
chemical_list: D006360:Heat-Shock Proteins; D011994:Recombinant Proteins