Expression of Pro-inflammatory Genes in Lesions and Neutrophils during Leishmania major Infection in BALB/c Mice

BACKGROUND Leishmaniasis is a worldwide disease prevalent in tropical and sub-tropical countries in the world. Characterization of inflammatory responses produced in cutaneous leishmaniasis has not yet been completed. METHODS The specific primers were designed for ten pro-inflammatory genes including CCL4, CCL3, TNF-α, IL-1α, IL-12P35, IL-12P40, CCL5, CCR5, IL-1β and IFN- γ and their expression were assessed and compared using RT-PCR in the lesion and peripheral blood neutrophils in Leishmania infected BALB/c mice. RESULTS None of the pro-inflammatory genes was expressed in the healthy tissue and except IFN-γ others were down-regulated by the parasite in the lesion in untreated mice. In mice treated with anti-Leishmanial drugs, the expression of the pro-inflammatory genes restarted. The figure of pro-inflammatory gene expression in neutrophils was different was from the lesions in treated and untreated mice. CONCLUSION Leishmania is capable to suppress the expression of pro-inflammatory genes in the lesions but not in neutrophils. The expression of TNF-α in the lesions and down-regulation of IL-1β in neutrophils could be accounted as an indication for healing of cutaneous leishmaniasis. The results open a new window on characterization of Leishmania lesions and clarifying the role of neutrophils in Leishmania infections.