title: Impaired stimulation of anti-bovine serum albumin IgG antibodies by vaccine adjuvants in murine acquired immunodeficiency syndrome.
abstract: The effect of three adjuvants - alum, N-acetylmuramyl-L-alanyl-D-isoglutamine (MDP), and liposomes - on the IgG antibody isotype response to bovine serum albumin (BSA), was determined in normal and LP-BM5 retrovirus infected C57BL/6 mice. Alum and MDP induced comparable levels of IgG antibodies in normal mice (predominantly IgG1 (greater than 90%)), whereas liposomes induced IgG1 (60%), IgG2a/b (30%) and IgG3 (10%) antibodies. IgG antibody levels using liposomes as adjuvant were five-fold higher than those observed with alum or MDP. Immunization after LP-BM5 infection significantly reduced the effectiveness of alum and MDP, IgG antibody levels being reduced by 80 and 90% at 3 or 7 weeks respectively. The adjuvant activity of liposomes was reduced by 55 and 65% when immunization was started 3 or 7 weeks post LP-BM5 infection. Boosting of pre-immune mice with BSA and alum, MDP or liposomes 3 weeks after LP-BM5 infection showed that, while the magnitude of the antibody response and isotype distribution was not affected, the persistence of the response was severely diminished compared to control, non-infected mice. The reduced immunoadjuvant activity correlated with a reduction in the frequency of splenic Thy1.2+/CD4+ T cells. These results demonstrated that liposomes were more effective than alum or MDP in inducing IgG antibodies, and that immunoadjuvant activity for prophylactic or therapeutic immunization for all 3 adjuvants was significantly impaired by retroviral infections.
authors.affiliation: Montreal General Hospital Research Institute, Quebec, Canada.
authors.forename: N C
authors.initials: NC
authors.lastname: Phillips
mesh_terms: D000119:Acetylmuramyl-Alanyl-Isoglutamine / Q000276:immunology / Q000494:pharmacology; D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000534:Alum Compounds / Q000494:pharmacology; D000818:Animals; D005260:Female; D007074:Immunoglobulin G / Q000096:biosynthesis*; D007132:Immunoglobulin Isotypes / Q000096:biosynthesis; D007156:Immunologic Memory; D008081:Liposomes / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D016183:Murine Acquired Immunodeficiency Syndrome / Q000276:immunology*; D012710:Serum Albumin, Bovine / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000276:immunology
chemical_list: D000276:Adjuvants, Immunologic; D000534:Alum Compounds; D007074:Immunoglobulin G; D007132:Immunoglobulin Isotypes; D008081:Liposomes; D012710:Serum Albumin, Bovine; C041524:aluminum sulfate; D000119:Acetylmuramyl-Alanyl-Isoglutamine