Apoptosis as a cause of T-cell unresponsiveness in experimental Chagas' disease.
A murine model of Chagas' disease induced by metacyclic forms of T. cruzi was used to evaluate T-cell function during infection. T-cell unresponsiveness to TcR;CD3 stimulation in vitro and lymphocyte activation in vivo occurred simultaneously. These paradoxical findings are discussed in the light of recent evidence that mature activated T cells become susceptible to TcR-mediated apoptosis. Activation-induced death in T cells from T. cruzi-infected mice has recently been demonstrated in this model. Evidence that TcR-induced death of activated T cells could be a cause for T-cell unresponsiveness in vitro and in vivo, as well as the possible molecular mechanisms involved, are discussed.
Lopes
M F
MF
Departamento de Imunologia, Universidade Federal do Rio de Janeiro, Brasil.
DosReis
G A
GA
D000818:Animals; D017209:Apoptosis / Q000276:immunology*; D014355:Chagas Disease / Q000276:immunology*; D008213:Lymphocyte Activation; D051379:Mice; D011948:Receptors, Antigen, T-Cell; D013601:T-Lymphocytes / Q000276:immunology* / Q000502:physiology; D014349:Trypanosoma cruzi / Q000276:immunology
D011948:Receptors, Antigen, T-Cell