title: Phosphorylcholine on isologous red blood cells induces polyclonal but not anti-phosphorylcholine plaque-forming cells in mice.
abstract: It has been demonstrated in the preceding report (Bach, M. A., Beckmann, E. and Levitt, D., Eur. J. Immunol. 1984. 14: 589) that phosphorylcholine (PC) on the bacterium Streptococcus pneumoniae R36a stimulated polyclonal as well as anti-PC plaque-forming cells (PFC) in mouse spleen in vivo. In this study, red blood cells from BALB/c mice (MRBC) were either conjugated with PC, 2,4,6-trinitrophenyl (TNP) or treated with phospholipase A2 (PLA2) to expose PC on the cell membrane (determined by hemagglutination with the anti-PC myeloma HOPC8). When BALB/c mice were immunized i.v. with the conjugated or enzyme-treated MRBC, a significant polyclonal antibody response occurred (p less than 0.05) using PC-MRBC or PLA2-treated MRBC, but not with TNP-MRBC or sham-treated MRBC. No anti-PC or anti-MRBC immunoglobulin-secreting cells developed after immunization. Repeated immunization with PC-MRBC resulted in similar levels of protein A PFC after each immunization but no anti-PC, anti-MRBC or anti-PC-MRBC PFC. Thus, PC on R36a or isologous RBC stimulated increased numbers of splenic plaque-forming cells. In the case of R36a, 10-25% of these PFC produced antibodies directed towards PC. In contrast, PC-MRBC or PLA2-treated MRBC, failed to evoke any anti-PC antibody responses.
mesh_terms: D000818:Animals; D000917:Antibody Formation; D000921:Antibody-Producing Cells / Q000276:immunology; D002794:Choline / Q000031:analogs & derivatives*; D004912:Erythrocytes / Q000276:immunology*; D005260:Female; D006241:Haptens; D006462:Hemolytic Plaque Technique; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D010767:Phosphorylcholine / Q000276:immunology*; D013045:Species Specificity; D013291:Streptococcus / Q000276:immunology
chemical_list: D006241:Haptens; D010767:Phosphorylcholine; D002794:Choline