Induction of idiotype-specific suppressor T cells with antigen/antibody complexes.
The effects of immune complexes on the antibody response of BALB/c mice to Streptococcus pneumoniae R36a (Pn) were investigated. The cell wall polysaccharide (PnC) extracted from Pn was used to form complexes with TEPC-15, a myeloma protein that binds to phosphorylcholine determinants on the PnC. Complexes formed at equivalence were cultured with splenic T cells from BALB/c mice for 2 d, and then the cells were added to fresh BALB/c spleen cell cultures to test their effect on the antibody response to Pn, a response dominated by the T15 idiotype family. The results indicate that TEPC-15/PnC complexes induced potent suppressor T cells (Ts) whereas cells cultured with free antigen or free antibody alone had no effect on the plaque-forming cell response to Pn. The suppression was specific since the response to control antigens such as sheep erythrocytes was unaffected. The suppression appears to be idiotype-specific since the Ts had a relatively weak (and in some cases no) effect on the anti-Pn response of BALB/c mice that had been suppressed for T15 idiotopes by neonatal injection of a monoclonal anti-T15 antibody, MaId 5-4. Furthermore, cells cultured with TEPC-15/PnC complexes were shown to express specific receptors for TEPC-15 idiotopes. The results indicate that antigen/antibody complexes may have important immunoregulatory effects because they are potent inducers of idiotype-specific Ts.
D000818:Animals; D000936:Antigen-Antibody Complex / Q000276:immunology*; D002478:Cells, Cultured; D005455:Fluorescent Antibody Technique; D007070:Immunoglobulin A / Q000276:immunology; D007130:Immunoglobulin Idiotypes / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D009194:Myeloma Proteins / Q000276:immunology; D011135:Polysaccharides, Bacterial / Q000276:immunology; D013296:Streptococcus pneumoniae; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
D000936:Antigen-Antibody Complex; D007070:Immunoglobulin A; D007130:Immunoglobulin Idiotypes; D009194:Myeloma Proteins; D011135:Polysaccharides, Bacterial