IL-10 inhibits T cell-independent but not T cell-dependent responses in vitro.
Lymphokines play a key role in T cell-independent (TI) Ag-induced responses. We recently showed that IL-10 potently inhibits Ig production stimulated by TI-2 Ag + IL-5. In view of our recent findings that the B cell activator can determine the effect lymphokines will have on Ig production and on isotype selection, we analyzed the effect of IL-10 on Ig production induced by other TI antigens and T cell-dependent Ag. These data demonstrate that IL-10 inhibited IL-5-induced Ig production stimulated by TI-1 and by TI-2 Ag, but had no effect on an in vitro T cell-dependent Ag-specific anti-SRBC-induced response or on a T cell-induced polyclonal response mediated by anti-CD3-activated T cell clones. IL-10 inhibited IgM, IgG1, IgG2a, and IgG3 secretion by B cells costimulated by LPS or anti-delta-dextran. IL-10 did not interfere with induction of class II MHC Ag expression or cell enlargement that was stimulated by LPS or anti-delta-dextran and had no detrimental effect on cell viability. IL-4 reversed the IL-10-mediated inhibition of IgG1 and IgM secretion stimulated by anti-delta-dextran or LPS-activated cells in the presence of IL-5. A 72 h, but not 24 h, exposure to IL-4 at initiation of culture with anti-delta-dextran + IL-5 + IL-10 was necessary to reverse the IL-10-mediated inhibition of IgM secretion. Our data suggest that IL-10 can selectively inhibit TI Ag-induced responses when other T cell-derived stimulatory lymphokines are not present and further emphasize the specific role of the B cell activator in influencing the responsiveness of B cells to lymphokines.
Peçanha
L M
LM
Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4799.
Snapper
C M
CM
Lees
A
A
Yamaguchi
H
H
Mond
J J
JJ
D000818:Animals; D000917:Antibody Formation / Q000187:drug effects*; D000955:Antigens, T-Independent / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology; D002478:Cells, Cultured; D005260:Female; D007132:Immunoglobulin Isotypes / Q000096:biosynthesis; D016753:Interleukin-10 / Q000494:pharmacology*; D007376:Interleukin-2 / Q000494:pharmacology; D015847:Interleukin-4 / Q000494:pharmacology; D015848:Interleukin-5 / Q000494:pharmacology; D008213:Lymphocyte Activation; D051379:Mice; D008811:Mice, Inbred DBA; D013601:T-Lymphocytes / Q000276:immunology*
D000955:Antigens, T-Independent; D007132:Immunoglobulin Isotypes; D007376:Interleukin-2; D015848:Interleukin-5; D016753:Interleukin-10; D015847:Interleukin-4