Cognate interactions between helper T cells and B cells. VI. TGF-beta inhibits B cell activation and antigen-specific, physical interactions between Th and B cells.
TGF-beta is a 25-kDa homodimeric protein that has been shown to have multiple roles in the regulation of lymphocyte activation. Previous studies have shown that TGF-beta is an inhibitor of numerous T and B lymphocyte activities. This study shows that TGF-beta is able to inhibit Th- and mitogen-induced murine B cell proliferation, as well as mitogen-induced B cell cycle entry and immunoglobulin secretion. Acridine orange analysis established that TGF-beta inhibits the LPS-induced B cell transition from G0 to G1A phase of the cell cycle. Evaluation of the effects of TGF-beta on the interactions between Th and B cells showed that TGF-beta inhibited antigen-specific Th-B cell physical interactions. Flow cytometric data showed that the ability of TGF-beta to interfere with the formation of Th-B cell conjugates was not due to decreased expression of IgD, IgM, class I, class II, LFA-1, or ICAM1 by the B cell. Taken together, these data establish that TGF-beta is able to act at multiple sites within the immune system.
Bartlett
W C
WC
Department of Microbiology, Dartmouth Medical School, Hanover, NH 03755.
Purchio
A
A
Fell
H P
HP
Noelle
R J
RJ
D000818:Animals; D000911:Antibodies, Monoclonal; D000938:Antigen-Presenting Cells / Q000276:immunology; D000954:Antigens, Surface / Q000032:analysis; D001402:B-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D002450:Cell Communication / Q000187:drug effects*; D002453:Cell Cycle / Q000187:drug effects; D002478:Cells, Cultured; D002999:Clone Cells; D004261:DNA Replication / Q000187:drug effects; D005260:Female; D015395:Histocompatibility Antigens Class I / Q000276:immunology; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D007075:Immunoglobulin M / Q000096:biosynthesis; D007700:Kinetics; D008213:Lymphocyte Activation / Q000187:drug effects; D051379:Mice; D008811:Mice, Inbred DBA; D008934:Mitogens; D011994:Recombinant Proteins / Q000494:pharmacology; D006377:T-Lymphocytes, Helper-Inducer / Q000187:drug effects / Q000276:immunology*; D016212:Transforming Growth Factor beta / Q000494:pharmacology*
D000911:Antibodies, Monoclonal; D000954:Antigens, Surface; D015395:Histocompatibility Antigens Class I; D000949:Histocompatibility Antigens Class II; D007075:Immunoglobulin M; D008934:Mitogens; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta