Comparison of different delivery systems of vaccination for the induction of protection against tuberculosis in mice

The way to deliver antigens and cellular requirements for long-lasting protection against tuberculosis are not known. Immunizations with mycobacterial 65 kDa heat shock protein (hsp65) expressed from J774-hsp65 cells (antigen-presenting cells that endogenously produce hsp65 antigen) or from plasmid DNA, or with the protein entrapped in cationic liposomes. can each give protective immunity similar to that obtained from live Bacillus Calmette Guerin (BCG), whereas injecting the protein in Freund's incomplete adjuvant (FIA) has minimal effect. Protective procedures elicited high frequencies of antigen-reactive rp T cells with CD4(+)/CD8(-) and CD8(+)/CD4(-) phenotypes. Protection correlated with the abundance of hsp65-dependent cytotoxic CD8(+)/CD4(-)/CD44(hi) cells. the frequency of these cells and the level of protection declined during 8 months after J774-hsp65 or liposome-mediated immunization with hsp65 protein but were sustained or steadily increased over this period after hsp65-DNA or BCG immunizations. IFN-gamma predominated over IL-4 among the hsp65-reactive CD8(+)/CD4(-) and CD4+/CD8(-) populations after J774-hsp65-, hsp65-liposome-, and hsp65-DNA-mediated immunizations, but similar levels of these cytokines prevailed after BCG vaccination. (C) 2001 Elsevier B.V. All rights reserved.Univ São Paulo, Sch Med Ribeirao Preto, Dept Biochem & Immunol, BR-14049900 Ribeirao Preto, SP, BrazilUniv São Paulo, Sch Pharmaceut Sci Ribeirao Preto, Dept Clin Anal Bromatol & Toxocol, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Microbiol & Immunol, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Microbiol & Immunol, São Paulo, BrazilWeb of Scienc