title: Qualitative and quantitative changes in the antibody producing cell response to lipopolysaccharide induced after incorporation of the antigen into bacterial membrane phospholipid vesicles.
abstract: Lipopolysaccharide (LPS) isolated from Proteus mirabilis and administered to mice i.p. induced a primary immune response that consisted of the proliferation of only IgM antibody-producing cells. The response to a second stimulus 14 days later was also predominantly IgM, although a smaller number of IgG-producing cells was detected. The strength of the responses depended upon the dosage of LPS administered. When mice received a primary injection of the same amount of LPS incorporated into P. mirabilis phospholipid vesicles, the number of IgM-producing cells was significantly increased over that induced by LPS alone. In addition, IgG-producing cells appeared on day 5 and increased during the time course measured up to day 14. After a booster injection of the same amount of LPS-phospholipid vesicles on day 14, the numbers of IgM-producing cells increased approximately 3-fold and the numbers of IgG-producing cells approximately 16-fold over those of mice given LPS alone. These results demonstrate a pronounced adjuvant effect of bacterial membrane phospholipids that are able to alter not only the strength but also the type of response to LPS.
mesh_terms: D000818:Animals; D000921:Antibody-Producing Cells / Q000276:immunology*; D000942:Antigens, Bacterial / Q000008:administration & dosage*; D002450:Cell Communication; D002462:Cell Membrane / Q000276:immunology; D005260:Female; D007074:Immunoglobulin G / Q000096:biosynthesis; D007075:Immunoglobulin M / Q000096:biosynthesis; D008070:Lipopolysaccharides / Q000494:pharmacology*; D051379:Mice; D010743:Phospholipids / Q000276:immunology*; D011513:Proteus mirabilis / Q000276:immunology; D011817:Rabbits
chemical_list: D000942:Antigens, Bacterial; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D008070:Lipopolysaccharides; D010743:Phospholipids