L eishmania donovani influenced cytokines and T oll‐like receptors expression among S udanese visceral leishmaniasis patients

Summary Leishmaniasis remains a serious health problem. The outcome of L eishmania infection depends on the early innate response. In this study, whole blood samples of 40 patients with visceral leishmaniasis ( VL ), 10 leishmanin skin test‐negative ( LST −ve) controls and 10 leishmanin skin test‐positive ( LST +ve) controls were stimulated by live L . donovani promastigotes. Also, THP 1 human cell line was infected with L . donovani . The production of interleukin 10 ( IL ‐10), tumour necrosis factor alpha ( TNF ) and interferon gamma ( IFNG ) cytokines was measured, and the expression of Toll‐like receptors ( TLR 2, TLR 4 and TLR 9) was done in the blood samples and also in the THP 1 cell line. IL ‐10 was found to be higher in LST +ve controls compared with VL patients. TNF was moderately produced with no variation between patients, controls and THP 1 cells. IFNG was higher in LST +ve controls also in THP 1 cells. TLR 4 and TLR 9 were found to be highly expressed in patients with VL . L . donovani increases the expression of TLR 4 and TLR 9 in patients with VL and TLR 2 in THP 1 cells, suggesting a TLR s relation in induction of a mixed cytokine response. TLR 9 was markedly recognized by L . donovani DNA .