The Role And Significance Of Th17 Cells And IL-17 In Severe Fever With Thrombocytopenia Syndrome

Objective:To investigate the levels and the roles of Thl7 cell and IL-17 in Severe fever with thrombocytopenia Syndrome(SFTS),and provide a novel theoretical evidence and strategy for the treatment of SFTS.Methods:According to the diagnostic criteria of SFTS prevention guide(2010 edition)issued by the Ministry of Health of the People's Republic of China,45 SFTS hospitalized patients were observed From April 2015 to August 2016,Yantai Infectious Diseases Hospital.At the same time,20 healthy control subjects were also collected.According to the clinical outcomes,the patients were divided into two groups: 38 in the survivor group and 7 in the death group.The percentage of Th17 cells was detected in the healthy control group,the survivor group and in the death group by flow cytometry.In addition,the serum levels of the IL-17 were also tested by enzymelinked immunosorbent assay(ELISA)in the three groups.The correlation between Th17 and IL-17 and clinical indicators were analyzed.Results:1.Compared with the healthy control group,the percentage of Thl7 cells and the serum levels of the IL-17 in the survivor group and the death group were obviously higher(P<0.05).Compared with the survivor group,the percentage of Thl7 cells and the serum levels of the IL-17 in the death group were higher(P<0.05).2.The percentage of Thl7 cells were positively correlated with the serum levels of the IL-17.(r=0.927,P<0.05).3.The percentage of Thl7 cells were negatively correlated with PLT,WBC(r=—0.743,P<0.05;r=—0.784,P<0.05),and positively correlated with ALT?AST?CK?LDH(r=0.851,P<0.05;r=0.838,P<0.05;r=0.776,P<0.05,r=0.901,P<0.05).4.The serum levels of IL-17 were negatively correlated with PLT,WBC(r=—0.689,P<0.05;r=—0.725,P<0.05),and positively correlated with ALT?AST?CK? LDH(r=0.778,P<0.05;r=0.766,P<0.05;r=0.692,P<0.05;r=0.863,P<0.05).Conclusion:Compared with the healthy control group,the percentage of Th17 cells and their related cytokines IL-17 are highly expressed in the serums of SFTS patients in the survivor group and the death group.Compared with the survivor group,the serum level of Th17 cells and their related cytokines IL-17 with SFTS patients in the death group wereobviously higher.The percentage of Thl7 cells were positively correlated with the serum levels of the IL-17.The percentage of Thl7 cells and the serum levels of IL-17 were negatively correlated with PLT,WBC and correlated with positively ALT?AST?CK?LDH.Detecting the percentage of Th17 cells and expression of IL-17 would contribute to prediction of the disease progression and prognosis.