Induction of T cell adhesion by antigen stimulation and modulation by the coreceptor CD4.
T cell adhesion induced after physiological stimulation by antigen was investigated using murine T cell hybridomas specific for a tetanus toxin peptide. By employing a novel assay, the T cell hybridomas were shown to strongly adhere to peptide-pulsed APC in a dose-dependent fashion. Adhesion peaked at 30-60 min and declined thereafter. This assay allowed us to study the relationship between T cell adhesion and later activation responses using tetanus toxin peptide and alanine monosubstituted analogs. We show that the degree of peptide-induced T cell adhesion correlated with the magnitude of late functional responses. CD4, LFA-1 (CD11a/CD18), and CD28 were critical in the adhesion response. The enhancing role of CD4 was further demonstrated by reduced levels of T cell adhesion and late responses of CD4- T cell hybridomas. Reexpression of CD4 reversed these defects. Our data suggest a link between antigen-induced T cell adhesion and late responses and also suggest that signals mediated by TCR and CD4 coengagement may induce a greater activation and/or recruitment of molecules involved in T cell adhesion.
Michel
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F
Molecular Immunology Unit, Department of Immunology, Pasteur Institute, Paris, France.
Acuto
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O
D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology; D000941:Antigens / Q000276:immunology*; D015704:CD4 Antigens / Q000276:immunology*; D002448:Cell Adhesion; D015815:Cell Adhesion Molecules / Q000378:metabolism; D006801:Humans; D006825:Hybridomas; D007739:L Cells; D008213:Lymphocyte Activation; D051379:Mice; D013601:T-Lymphocytes / Q000276:immunology*; D013744:Tetanus Toxin / Q000276:immunology
D000941:Antigens; D015704:CD4 Antigens; D015815:Cell Adhesion Molecules; D013744:Tetanus Toxin