Leishmania braziliensis: partial control of experimental infection by interleukin-12 p40 deficient mice.
Resistance to infection by Leishmania major has been associated with the development of a Th1 type response that is dependent on the presence of interleukin 12 (IL-12). In this work the involvement of this cytokine in the response to infection by L. braziliensis, a less virulent species in the mouse model, was evaluated. Our results show that while interferon (IFN-gamma) deficient (-/-) mice inoculated L. braziliensis develop severe uncontrolled lesions, chronic lesions that remained under control up to 12 weeks of infection were observed in IL-12p40 -/- mice. IL 12p40 -/- mice had fewer parasites in their lesions than IFN-gamma (-/-) mice. Lymph node cells from IL-12p40 -/- were capable of producing low but consistent levels of IFN-gamma suggestive of its involvement in parasite control. Furthermore, as opposed to previous reports on L. major-infected animals, no switch to a Th2 response was observed in IL-12p40 -/- infected with L. braziliensis.
Departamento de Ciências Biológicas, Instituto de Ciências Exatas e Biológicas, Brasil.
Sebastião Martins
SM
de Souza-Neto
Cláudia Martins
CM
Carneiro
Leda Quercia
LQ
Vieira
Luís Carlos Crocco
LC
Afonso
D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D007371:Interferon-gamma / Q000096:biosynthesis / Q000276:immunology*; D018664:Interleukin-12 / Q000096:biosynthesis / Q000172:deficiency* / Q000276:immunology; D053762:Interleukin-12 Subunit p40; D007892:Leishmania braziliensis / Q000276:immunology*; D016773:Leishmaniasis, Cutaneous / Q000276:immunology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D021122:Protein Subunits / Q000096:biosynthesis / Q000172:deficiency* / Q000276:immunology; D013997:Time Factors
D053762:Interleukin-12 Subunit p40; D021122:Protein Subunits; D018664:Interleukin-12; D007371:Interferon-gamma