Comparision of the effects of Leishmania Soluble Antigen (LSA) and Lipopolysaccharide (LPS) on C57BL/6 Mice Macrophage Function

Background: Macrophages activation is the important anti-leishmania immune response. Different signals could affect macrophages development and functional activation. Objectives: In the present study, we compared the effect of Leishmania Soluble Antigen (LSA)and Lipopolysaccharide (LPS) on peritoneal macrophage responses. Appropriate activation of macrophages depends on thesignals they receive from pathogens and their different functional differentiation is crucial for anti-leishmania effects ofmacrophages. Methods and materials: In order to assay C57BL/6 mice macrophage function after LPS or LSA treatment, we measured phagocyticactivity, cytokine pattern, and Nitric Oxide (NO) production by macrophages. Results: Phase contrast microscopy showed thatLPS-treated macrophages became more granular and spindle-shaped and similar to untreated macrophages, LSA-treatedcells displayed round and spindle-shaped morphology. In addition, Nitric oxide assay and cytokine analysis showed thatIL-6, IL-10, and TNF-α production was significantly reduced in LSA-treated macrophages in comparison with LPS-stimulatedcells. It was also found that LSA-treated macrophages represented an anti-inflammatory phenotype compared with LPStreatedmacrophages. Conclusion: This anti-inflammatory phenotype was related to increase in IL-10 / TNF- α production of LSA-treatedmacrophages and there was no difference in the amount of TGF-β between LSA- and LPS-treated groups.