Leishmania braziliensis: partial control of experimental infection by interleukin-12 p40 deficient mice

• Autor(a) principal: Souza-Neto,Sebastião Martins de
• Data de Publicação: 2004
• Outros Autores: Carneiro,Cláudia Martins, Vieira,Leda Quercia, Afonso,Luís Carlos Crocco
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Memórias do Instituto Oswaldo Cruz
• Texto Completo: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0074-02762004000300009
• topic: cutaneous leishmaniasis; Leishmania braziliensis; interleukin 12

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<FONT FACE=Symbol>-g</FONT>) 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<FONT FACE=Symbol>-g</FONT>-/- mice. Lymph node cells from IL-12p40 -/- were capable of producing low but consistent levels of IFN<FONT FACE=Symbol>-g</FONT> 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.