Reduced CD3-mediated protein tyrosine phosphorylation in anergic CD4+ and CD8+ T cells.
J Immunol
; 151(5): 2355-67, 1993 Sep 01.
Article
em En
| MEDLINE
| ID: mdl-8103063
ABSTRACT
Mice inoculated i.v. with superantigens exhibit long lived Ag-specific T cell tolerance. An in vitro model for this phenomenon is the ensuing unresponsiveness of Th1 T cell clones activated via the TCR/CD3 complex in the absence of co-stimulation. We have previously demonstrated alterations in TCR-mediated early protein tyrosine phosphorylation events in Th1 clones anergic for IL-2 production. In this study, we demonstrate unresponsiveness in CD4+ and CD8+ T cells from V beta 8.1 transgenic mice inoculated i.v. with the superantigen Mls-1a. The unresponsiveness of both CD4+ and CD8+ T cells involves defective IL-2 production upon restimulation, with CD4+ T cells exhibiting an additional defect in IL-2 utilization. The transgenic model allowed study of T cell signaling in a relatively homogeneous population of unresponsive cells without elaborate purification of Ag-reactive populations. Both CD4+ and CD8+ T cells exhibit altered tyrosine phosphorylation of two protein substrates upon CD3-mediated restimulation. The substrates involved, p38 and p75, are of identical size to substrates similarly affected in anergic Th1 clones. Altered tyrosine phosphorylation is therefore closely associated with defective IL-2 production in these three anergic T cell types, and may play a role in the maintenance of anergy.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Tirosina
/
Linfócitos T
/
Proteínas
/
Complexo CD3
/
Tolerância Imunológica
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
J Immunol
Ano de publicação:
1993
Tipo de documento:
Article