Chemokine gene expression in toll-like receptor-competent and -deficient mice infected with Leishmania major.

We studied the expression of a subset of chemokines, including RANTES/CCL5, MIP-1alpha/CCL3, IP-10/CXCL10, and MCP-1/CCL2, in Toll-like receptor (TLR)-competent and -deficient mice after infection with Leishmania major. Chemokine expression at the site of infection (the footpad), in the draining lymph nodes and in the spleens of infected animals was determined by using two different methods of analysis. The results indicate that L. major infection causes overall upregulation of RANTES/CCL5, MIP-1alpha/CCL3, IP-10/CXCL10, and MCP-1/CCL2 in the footpads and lymph nodes, while expression of these chemokines is constitutive in the spleens of TLR4-competent mice (C57BL/10ScSn) and TLR4-deficient mice (C57BL10/ScN). Different patterns of expression were detected depending on the time postinfection, but there was little variation in the expression of these four chemokines in the presence or absence of TLR4.