title: Cytokines, signaling pathways, and effector molecules required for the control of Leishmania (Viannia) braziliensis in mice.
abstract: Cutaneous leishmaniasis is caused by protozoan parasites of the genus Leishmania. The mechanisms of pathogen control have been established primarily in the mouse model of Leishmania major infection, but they might not hold true for other Leishmania species associated with cutaneous disease. Here, we analyzed the role of cytokines, signaling components, and effector molecules in the control of New World cutaneous leishmaniasis due to L. braziliensis. Unlike L. major, L. braziliensis caused small, nonulcerative, and self-healing skin swelling in C57BL/6 mice, as well as BALB/c mice. In contrast to the results obtained for L. mexicana, mice deficient for interleukin-12 or its key signaling molecule, signal transducer and activator of transcription 4, rapidly succumbed to severe visceral leishmaniasis. Infection of tumor necrosis factor knockout mice with L. braziliensis led to progressive, nonhealing skin lesions with erosions and hemorrhagic ulcerations, but in contrast to the results with L. major, only 20 to 30% of the mice developed fatal visceral disease. As seen with L. major, mice with a deleted inducible nitric oxide synthase gene (iNOS(-/-)) were unable to contain L. braziliensis in the skin, whereas the control of the parasite in the spleen remained unimpaired. Unlike what happens in L. major infections, NADPH oxidase had no impact on the course of disease in L. braziliensis-infected mice. These results not only define essential components of a protective immune response to L. braziliensis but also illustrate that the requirements for the control of cutaneous leishmaniasis vary between different parasite species.
authors.affiliation: Mikrobiologisches Institut-Klinische Mikrobiologie, Immunologie und Hygiene, Universitätsklinikum Erlangen, Wasserturmstrasse 3-5, D-91054 Erlangen, Germany.
authors.forename: F Janaina Soares
authors.initials: FJ
authors.lastname: Rocha
authors.forename: Ulrike
authors.initials: U
authors.lastname: Schleicher
authors.forename: Jochen
authors.initials: J
authors.lastname: Mattner
authors.forename: Gottfried
authors.initials: G
authors.lastname: Alber
authors.forename: Christian
authors.initials: C
authors.lastname: Bogdan
mesh_terms: D000818:Animals; D004268:DNA-Binding Proteins / Q000276:immunology; D004195:Disease Models, Animal; D005260:Female; D018664:Interleukin-12 / Q000276:immunology*; D007892:Leishmania braziliensis / Q000276:immunology*; D018320:Leishmania major / Q000276:immunology; D016773:Leishmaniasis, Cutaneous / Q000276:immunology* / Q000473:pathology; D007898:Leishmaniasis, Visceral; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D019255:NADPH Oxidases / Q000276:immunology; D052247:Nitric Oxide Synthase Type II / Q000276:immunology*; D050797:STAT4 Transcription Factor / Q000276:immunology*; D015398:Signal Transduction; D012867:Skin / Q000473:pathology; D013154:Spleen / Q000469:parasitology; D014157:Transcription Factors / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology*
chemical_list: D004268:DNA-Binding Proteins; D050797:STAT4 Transcription Factor; C494091:Stat4 protein, mouse; D014157:Transcription Factors; D014409:Tumor Necrosis Factor-alpha; C055473:enhancer-binding protein AP-4; D018664:Interleukin-12; D052247:Nitric Oxide Synthase Type II; D019255:NADPH Oxidases