T-CELL IMMUNITY AFTER A VIRAL-INFECTION VERSUS T-CELL TOLERANCE INDUCED BY SOLUBLE VIRAL PEPTIDES

The fate of in vivo activated CD8+ cytotoxic T cells was studied in tr ansgenic mice expressing a T cell receptor (TCR) specific for the lymp hocytic choriomeningitis virus (LCMV) glycoprotein peptide 33-41 prese nted by major histocompatibility complex (MHC) class I molecules. LCMV infection of TCR transgenic mice induced LCMV-specific effector and m emory T cells whereas injection of soluble LCMV glycoprotein peptide 3 3-41 resulted in tolerance by peripheral deletion and anergy of LCMV-s pecific T cells after an initial expansion phase. Similarly, LCMV pept ide 33-41-specific tolerance could be achieved in normal C57BL/6 mice and was not abrogated by an LCMV infection. These results obtained wit h a classically MHC-restricted peptide antigen parallel previous findi ngs with retroviral or bacterial superantigens and indicate a possibil ity to modulate specifically mature peripheral cytotoxic T lymphocytes in vivo.