Expression and significance of myocardial interleukin-17A in mice with viral myocarditis

Abstract

Objective To explore the expression of interleukin-17A(IL-17A) in the myocardium of mice with experimental viral myocarditis(VM) and its clinical significance. Methods Fifty-five mice were randomly divided into myocarditis group(n=45) and control group(n=10). Mice in the myocarditis group were inoculated intraperitoneally with 0.1 mL Eagle's solution containing coxsackievirus B3(CVB3) to establish VM models.However, mice in the control mice were treated with 0.1 mL Eagle's solution.Ten infected mice were sacrificed on day 7, 14 and 28 after inoculation, and the control mice were killed on day 28 postinoculation.Myocardial histopathology was determined with hematoxylin and eosin stain.The levels of myocardial IL-17A mRNA and protein expressions were detected by real time quantitative polymerase chain reaction(RQ-PCR) and immunohistochemistry.Serum IL-17A concentration was examined using enzyme linked immunosorbent assay(ELISA). In addition, the relationship between myocardial IL-17A protein levels as well as serum IL-17A concentration and myocardial histopathological scores were analyzed statistically in myocarditis group. Results The levels of myocardial IL-17A mRNA and protein and serum IL-17A concentration on day 7 and 14 after inoculation in myocarditis group increased significantly compared with those in control group(all P<0.01). Myocardial IL-17A protein levels and serum IL-17A concentration showed significantly positive correlation with the myocardial histopathologic scores in VM group, respectively(r=0.67, 0.74, all P<0.05). Conclusions IL-17A may play a pivotal role in the pathogenesis of VM and is associated with the severity of VM.It can serve as a novel indicator for VM. Key words: Interleukin-17A; Viral myocarditis; Coxsackievirus B3