title: Exposure to mycobacteria primes the immune system for evolutionarily diverse heat shock proteins.
abstract: During stress conditions, such as infection, the synthesis of heat shock proteins (HSPs) in microorganisms is upregulated. Since a high degree of homology exists within each HSP family, we postulated that exposure to microorganisms could prime the immune system for evolutionarily diverse HSPs. We tested this hypothesis by priming mice with three microorganisms, namely, Mycobacterium bovis BCG, Mycobacterium vaccae, and Chlamydia pneumoniae. After this, mice received a dose of the various HSPs. We found that BCG and M. vaccae but not C. pneumoniae primed the immune system for the induction of secondary immunoglobulin G (IgG) responses to most of the HSPs tested. Analysis of the IgG1 and IgG2a profile and gamma interferon production induced against the HSPs revealed the induction of a mixture of responses. We also observed that sera from mice treated with M. vaccae and HSP70 were cross-reactive, but no antibody complexes were observed in their kidneys, which frequently are targets for autoantibody reactions. Our findings add further support for the use of HSPs as effective vaccine adjuvants.
authors.affiliation: Department of Immunology, Wenner-Gren Institute, Stockholm University, SE-106 91 Stockholm, Sweden.
authors.forename: Khaleda Rahman
authors.initials: KR
authors.lastname: Qazi
authors.forename: Mousumi Rahman
authors.initials: MR
authors.lastname: Qazi
authors.forename: Esther
authors.initials: E
authors.lastname: Julián
authors.forename: Mahavir
authors.initials: M
authors.lastname: Singh
authors.forename: Manuchehr
authors.initials: M
authors.lastname: Abedi-Valugerdi
authors.forename: Carmen
authors.initials: C
authors.lastname: Fernández
mesh_terms: D000818:Animals; D000906:Antibodies / Q000276:immunology; D000953:Antigens, Protozoan / Q000276:immunology; D016993:Chlamydophila pneumoniae / Q000276:immunology / Q000378:metabolism; D003429:Cross Reactions / Q000276:immunology; D005260:Female; D006360:Heat-Shock Proteins / Q000737:chemistry* / Q000276:immunology* / Q000378:metabolism; D007109:Immunity / Q000276:immunology*; D007074:Immunoglobulin G / Q000097:blood; D007371:Interferon-gamma / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D009161:Mycobacterium / Q000276:immunology* / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D000906:Antibodies; D000953:Antigens, Protozoan; D006360:Heat-Shock Proteins; D007074:Immunoglobulin G; D007371:Interferon-gamma