T cell activation through TCR/-CD3 complex. IL-2 production of T cell clones stimulated with anti-CD3 without cross-linkage.
To elucidate the Th cell activation mechanism through the TCR/CD3 complex, we examined the reactivity of T cell clones to soluble monovalent and divalent anti-CD3 without accessory cells or costimulatory factor. All T cell clones tested produced IL-2 in response to monovalent anti-CD3, although reactivity to divalent anti-CD3 was variable depending upon clones. IL-2 production of T cell clones induced by monovalent anti-CD3 was suppressed by cross-linking of the antibody with anti-hamster IgG. IL-2 mRNA expression and the increment of intracellular Ca2+ concentration were consistent with the IL-2 production. When T cell clones were stimulated with monovalent anti-CD3, they increased in size, although divalent anti-CD3 stimulation did not affect their size irrespective of their IL-2 production. These results indicate that monovalent anti-CD3 is more efficient than divalent anti-CD3 in induction of IL-2 production and that the cross-linkage of the TCR/CD3 complex is not necessarily required for the T cell clone activation.
Tamura
T
T
Department of Allergology, University of Tokyo, Japan.
Nariuchi
H
H
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000945:Antigens, Differentiation, T-Lymphocyte / Q000276:immunology / Q000502:physiology*; D017252:CD3 Complex; D015704:CD4 Antigens / Q000502:physiology; D002118:Calcium / Q000378:metabolism; D002999:Clone Cells; D007376:Interleukin-2 / Q000096:biosynthesis* / Q000235:genetics; D008213:Lymphocyte Activation; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D012333:RNA, Messenger / Q000032:analysis; D011948:Receptors, Antigen, T-Cell / Q000276:immunology / Q000502:physiology*; D013601:T-Lymphocytes / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte; D017252:CD3 Complex; D015704:CD4 Antigens; D007376:Interleukin-2; D012333:RNA, Messenger; D011948:Receptors, Antigen, T-Cell; D002118:Calcium