Can peritoneal B cells be rendered unresponsive?
Ly-1+ B cells have been reported to produce a number of autoantibodies, and to be involved in the selection and regulation of the conventional B cell repertoire. It is not known if these B cells, which are found in high numbers in the peritoneum of normal adult mice, themselves can be regulated. In this study, we evaluated the sensitivity of peritoneal B cells (PBCs) versus conventional splenic B cells to regulation in a model system for tolerance. Normal splenic (conventional) or PBCs (containing both CD5+ and CD5– sister cells) were cultured overnight with either F(ab )2 or intact IgG anti-mouse Ig, washed, and then challenged with fluorescein(FL)-coupled to Brucella abortus (BA), trlmethylammonium (TMA)-BA or lipopolysaccharide (LPS), and the IgM responses to the FL and TMA haptens measured. In contrast to spleen cells, which exhibited up to a 90% reduction in anti-FL responsiveness, pretreated PBCs were mostly resistant to this form of tolerance regardless of challenge. The anti-TM
