Effect of intravenous injecting plasmid encoding interleukin-19-IgG on experimental autoimmune myocarditis in rats

AIM: To evaluate the effect of intravenous injecting plasmid encoding interleukin-19-IgG on experimental autoimmune myocarditis (EAM) in rats.METHODS: Cardiac myosin was emulsified with equal volume of complete Freund's adjuvant. The animal model of EAM was established by injecting with the preparation in both footpads of the Lewis rats. The rats were intravenously injected with the plasmid encoding IL-19-IgG on day 6. Echocardiography was performed before the rats were sacrificed on day 17. The effect of IL-19-IgG plasmid injection was evaluated by measuring the heart weight/body weight, myocarditis area, relative expression levels of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) in the hearts. The mRNA expression levels of related cytokines including IL-18, IL-1β, IL-12p35 and IFN-γ were detected.RESULTS: The rats in model group showed significant myocardial damage and a decrease in the left ventricular functions. The rats in the treatment group injected with IL-19-IgG plasmid showed an improvement of the cardiac functions. The ratio of heart weight/body weight, the area of myocarditis and the mRNA levels of ANP and BNP were significantly lower in IL-19-IgG treatment group than those in model group. The mRNA levels of IL-18, IL-1β, IL-12p35 and IFN-γ were also significantly decreased in IL-19-IgG treatment group.CONCLUSION: Intravenous injection of plasmid encoding IL-19-IgG effectively prevents the development of the left ventricular remodeling and myocardial damage in EAM rats.