title: The effect of anti-CD4 on helper function of CD4,45RA+ versus CD4,45RO+ T cells.
abstract: Here we have investigated and compared the effects of anti-CD4 on helper function of CD4,45RA+ versus CD4,45RO+ T cells. Only CD4,45RO+ cells, but not CD4,45RA+ cells were able to promote B cell differentiation resulting in immunoglobulin production in vitro (IgM as well as IgG) which could be inhibited by anti-CD4 MoAbs (MAX.16H5 and T151). In pokeweed mitogen (PWM)-induced B cell proliferation a similar pattern of responsiveness was obtained. When we studied the anti-CD4 effects on cytokine production in T cells stimulated in mixed lymphocyte reaction (MLR) or by mitogens, we found that neither IL-2 nor IL-4 production was dramatically influenced by anti-CD4 in CD4,45RO+ cells. This led us to the conclusion that the inhibitory effect of anti-CD4 on B cell proliferation and immunoglobulin secretion was not due to inhibition of cytokine production. To clarify this point, we investigated the ability of anti-CD4 to inhibit conjugate formation between B and T cells. It was found that CD4,45RO+ T cells formed more conjugates than CD4,45RA+ cells, and that only the conjugate formation by CD4,45RO+ T cells was inhibited by anti-CD4. These results suggest that (i) anti-CD4 inhibits T helper functions primarily by affecting CD4,45RO+ cells, and (ii) this effect is probably mediated by contact inhibition in the early phase of T-B collaboration.
authors.affiliation: Max-Planck-Gesellschaft, Klinische Arbeitsgruppe für Rheumatologie/Immunologie Universität Erlangen-Nürnberg, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Wang
authors.forename: T
authors.initials: T
authors.lastname: Yan
authors.forename: B
authors.initials: B
authors.lastname: Simmer
authors.forename: F
authors.initials: F
authors.lastname: Emmrich
mesh_terms: D000911:Antibodies, Monoclonal / Q000276:immunology*; D001402:B-Lymphocytes / Q000502:physiology; D015704:CD4 Antigens / Q000032:analysis / Q000276:immunology*; D002450:Cell Communication; D002454:Cell Differentiation; D002460:Cell Line; D006801:Humans; D007136:Immunoglobulins / Q000096:biosynthesis; D017493:Leukocyte Common Antigens / Q000032:analysis*; D008222:Lymphokines / Q000096:biosynthesis / Q000494:pharmacology; D016176:T-Lymphocyte Subsets / Q000502:physiology*; D006377:T-Lymphocytes, Helper-Inducer / Q000502:physiology*
chemical_list: D000911:Antibodies, Monoclonal; D015704:CD4 Antigens; D007136:Immunoglobulins; D008222:Lymphokines; D017493:Leukocyte Common Antigens