title: Plaque-forming cell response in BALB/c mice to two preparations of LPS extracted from Salmonella enteritidis.
abstract: The pattern of development of antibody-forming cells in BALB/c mice after immunization with PW-LPS or TCA-LPS was shown to be different. On days 10 and 20, the primary response to PW-LPS was characterized by a low level of IgM synthesis. The plaque-forming cell (PFC) response to TCA-LPS, however, increased from day 10 to day 20. Initially, IgM was the only detectable antibody synthesized but by day 20 a significant number of IgG-producing spleen cells had developed. After a secondary immunization with the appropriate lipopolysaccharide (LPS) preparation, IgG-producing spleen cells were detected in mice immunized with either PW-or TCA-LPS. Partial removal of the LAP or TCA-LPS with phenol or trypsin and pronase significantly reduced the PFC response, suggesting that the protein moiety played an influential role in the immunogenicity of TCA-LPS. The TCA-LPS contained the same antigenic dterminants as PW-LPS, so any difference observed between PFC response was not due to any associated immunogenic moiety.
mesh_terms: D000818:Animals; D004306:Dose-Response Relationship, Immunologic; D000939:Epitopes; D005260:Female; D006462:Hemolytic Plaque Technique; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D008070:Lipopolysaccharides / Q000032:analysis / Q000494:pharmacology*; D051379:Mice; D008807:Mice, Inbred BALB C; D010636:Phenols; D012477:Salmonella enteritidis / Q000276:immunology*; D013997:Time Factors; D014238:Trichloroacetic Acid; D014357:Trypsin / Q000494:pharmacology
chemical_list: D000939:Epitopes; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D008070:Lipopolysaccharides; D010636:Phenols; D014238:Trichloroacetic Acid; D014357:Trypsin