title: Prime-boost with Mycobacterium smegmatis recombinant vaccine improves protection in mice infected with Mycobacterium tuberculosis.
abstract: The development of a new vaccine as a substitute for Bacillus Calmette-Guerin or to improve its efficacy is one of the many World Health Organization goals to control tuberculosis. Mycobacterial vectors have been used successfully in the development of vaccines against tuberculosis. To enhance the potential utility of Mycobacterium smegmatis as a vaccine, it was transformed with a recombinant plasmid containing the partial sequences of the genes Ag85c, MPT51, and HspX (CMX) from M. tuberculosis. The newly generated recombinant strain mc(2)-CMX was tested in a murine model of infection. The recombinant vaccine induced specific IgG1 or IgG2a responses to CMX. CD4(+) and CD8(+) T cells from the lungs and spleen responded ex vivo to CMX, producing IFN-γ, IL17, TNF-α, and IL2. The vaccine thus induced a significant immune response in mice. Mice vaccinated with mc(2)-CMX and challenged with M. tuberculosis showed better protection than mice immunized with wild-type M. smegmatis or BCG. To increase the safety and immunogenicity of the CMX antigens, we used a recombinant strain of M. smegmatis, IKE (immune killing evasion), to express CMX. The recombinant vaccine IKE-CMX induced a better protective response than mc(2)-CMX. The data presented here suggest that the expression of CMX antigens improves the immune response and the protection induced in mice when M. smegmatis is used as vaccine against tuberculosis.
authors.affiliation: Instituto de Patologia Tropical e Saúde Pública. Universidade Federal de Goiás, Goiânia, Goiás, Brazil.
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Junqueira-Kipnis
authors.forename: Fábio Muniz
authors.initials: FM
authors.lastname: de Oliveira
authors.forename: Monalisa Martins
authors.initials: MM
authors.lastname: Trentini
authors.forename: Sangeeta
authors.initials: S
authors.lastname: Tiwari
authors.forename: Bing
authors.initials: B
authors.lastname: Chen
authors.forename: Danilo Pires
authors.initials: DP
authors.lastname: Resende
authors.forename: Bruna D S
authors.initials: BD
authors.lastname: Silva
authors.forename: Mei
authors.initials: M
authors.lastname: Chen
authors.forename: Lydia
authors.initials: L
authors.lastname: Tesfa
authors.forename: William R
authors.initials: WR
authors.lastname: Jacobs
authors.forename: André
authors.initials: A
authors.lastname: Kipnis
mesh_terms: D000818:Animals; D001500:BCG Vaccine / Q000008:administration & dosage; D001426:Bacterial Proteins / Q000235:genetics; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D006801:Humans; D051379:Mice; D020102:Mycobacterium smegmatis / Q000235:genetics / Q000276:immunology*; D009169:Mycobacterium tuberculosis / Q000187:drug effects / Q000472:pathogenicity; D014376:Tuberculosis / Q000382:microbiology / Q000517:prevention & control*; D032581:Tuberculosis Vaccines / Q000008:administration & dosage* / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis; D014614:Vaccines, Synthetic / Q000008:administration & dosage* / Q000276:immunology
chemical_list: D001500:BCG Vaccine; D001426:Bacterial Proteins; D032581:Tuberculosis Vaccines; D014409:Tumor Necrosis Factor-alpha; D014614:Vaccines, Synthetic