title: Limited role of the Toll-like receptor-2 in resistance to Mycobacterium avium.
abstract: The role of the Toll-like receptor (TLR)-2 in the generation of protective immunity to Mycobacterium avium was evaluated using gene-disrupted mice. TLR-2-/- mice were more susceptible than wild-type C57Bl/6 mice to M. avium strains that were able to proliferate in vivo before the development of protective immunity and mycobacteriostasis. In contrast, the elimination of non-virulent strains was not affected by the mutation. The generation of interferon-gamma (IFN-gamma)-producing T cells and the expression of the interleukin-12 p40 gene were reduced in TLR-2-deficient mice as compared to C57Bl/6 mice early during infection with M. avium strain 2447. The generation of protective CD4+ T cells was also compromised in the mutated mice as compared with the controls. Our data show that TLR-2 is required for optimal immunity against certain virulent M. avium strains.
authors.affiliation: Laboratory of Microbiology and Immunology of Infection, Institute for Molecular and Cell Biology, University of Porto, Porto, Portugal. sgomes@ibmc.up.pt
authors.forename: M Salomé
authors.initials: MS
authors.lastname: Gomes
authors.forename: Manuela
authors.initials: M
authors.lastname: Flórido
authors.forename: João V
authors.initials: JV
authors.lastname: Cordeiro
authors.forename: C Miguel
authors.initials: CM
authors.lastname: Teixeira
authors.forename: Osamu
authors.initials: O
authors.lastname: Takeuchi
authors.forename: Shizuo
authors.initials: S
authors.lastname: Akira
authors.forename: Rui
authors.initials: R
authors.lastname: Appelberg
mesh_terms: D019264:Adoptive Transfer; D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D020022:Genetic Predisposition to Disease; D007111:Immunity, Cellular / Q000235:genetics; D007371:Interferon-gamma / Q000096:biosynthesis; D018664:Interleukin-12 / Q000096:biosynthesis; D008264:Macrophages / Q000276:immunology / Q000382:microbiology; D008562:Membrane Glycoproteins / Q000235:genetics / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008817:Mice, Mutant Strains; D009162:Mycobacterium avium / Q000254:growth & development; D011956:Receptors, Cell Surface / Q000235:genetics / Q000276:immunology*; D013154:Spleen / Q000276:immunology; D051195:Toll-Like Receptor 2; D051193:Toll-Like Receptors; D014376:Tuberculosis / Q000276:immunology* / Q000517:prevention & control
chemical_list: D008562:Membrane Glycoproteins; D011956:Receptors, Cell Surface; D051195:Toll-Like Receptor 2; D051193:Toll-Like Receptors; D018664:Interleukin-12; D007371:Interferon-gamma