Immunoregulatory characteristics of the in vitro anti-ssDNA response.
Continuous blockade of B-cell antigen receptors (BCRs) with Fab alpha sIg prevents the anti-ssDNA response of high, but not low, density B cells. Signaling via the BCRs, by prior exposure to crosslinking F(ab')2 alpha sIg, had no effect on the spontaneous anti-DNA response, but prevented a lipopolysaccharide-induced anti-DNA response. Pretreatment with intact alpha sIg, which provides exogenously derived Fc signals, reduced the response. An Fc-signal-blocking agent, F(ab')2 anti-IgG-Fc antibody, increased the number of anti-DNA antibody-forming cells produced in the absence of exogenous IgG anti-ssDNA antibody. Thus, activation is dependent on the availability of the BCRs, prior BCR crosslinking does not interfere with activation, and endogenous IgG anti-ssDNA antibody limits the activation of anti-ssDNA-specific B cells most of which are T-cell independent. These results indicate that the anti-ssDNA response is driven through the BCR.
Anderson
C C
CC
Department of Microbiology and Immunology, University of Western Ontario, London, Canada.
Panoskaltsis
A
A
Sinclair
N R
NR
D000818:Animals; D000974:Antibodies, Antinuclear / Q000096:biosynthesis*; D002478:Cells, Cultured; D004277:DNA, Single-Stranded / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D004912:Erythrocytes / Q000276:immunology; D007140:Immunoglobulin Fab Fragments; D008070:Lipopolysaccharides / Q000276:immunology; D008213:Lymphocyte Activation; D051379:Mice; D008808:Mice, Inbred CBA; D008811:Mice, Inbred DBA; D011947:Receptors, Antigen, B-Cell / Q000276:immunology*; D011961:Receptors, Fc; D012756:Sheep / Q000276:immunology; D015398:Signal Transduction
D000974:Antibodies, Antinuclear; D004277:DNA, Single-Stranded; D007140:Immunoglobulin Fab Fragments; D008070:Lipopolysaccharides; D011947:Receptors, Antigen, B-Cell; D011961:Receptors, Fc