IL-17 Induced The Recruitment and Functional Activity of Granulocytes Isolated from Patients Coinfected with Schistosoma mansoni and Hepatitis C Virus.

The aim of this study was to investigate the role of Th17 cytokines on granulocytes recruitment and functional activity in Schistosoma mansoni/hepatitis C virus (HCV) co-infected patients. Granulocytes were isolated from the co-infected blood and stimulated overnight with Schistosoma soluble egg antigen (SEA) in the presence of IL-17, IL-22, or both cytokines. In parallel, granuloma was induced in vitro using the isolated granulocytes and SEA-coated polyacrylamide beads in the presence of IL-17 and/or IL-22 then the sizes of granulomas were measured after one week. Overnight culture and granuloma supernatants levels of tumor necrosis factor-alpha (TNF-?, hydrogen peroxide (H2O2) and nitric oxide (NO) were measured using ELISA. Results revealed that Schistosoma/HCV derived granulocytes produced significant (P < 0.0001) higher levels of TNF-? and H2O2 after overnight activation with SEA in the presence of IL-17 as compared to that produced by Schistosoma alone infected granulocytes. Presence of IL-17 increased significantly (P=0.0017) the granuloma index of coinfected patients' granulocytes as compared to that of Schistosoma alone infected granulocytes after one week of granuloma induction. Additionally, TNF-? and H2O2 levels in the granuloma supernatant were increased significantly (P = 0.0009 and P=0.0074 respectively) as compared to that of Schistosoma alone infected granulocytes. However, IL-22 alone or when combined with IL-17 decreased significantly the TNF-? levels (P=0.0112 and P=0.0007 respectively), and H2O2 levels (P=0.002 and P=0.053 respectively) but increased NO levels (P < 0.0001 and P=0.002 respectively) in the granuloma supernatant. In conclusion, IL-17 induces recruitment and functional activity of granulocytes in coinfected with schistosomiasis and hepatitis C virus which may contribute to the progress of fibrosis. Neutralization of this cytokine is suggested as a therapeutic strategy against fibrosis for such category of patients.