The optimization of viral infection dose in Coxsackievirus-induced murine model of viral myocarditis

To optimize the viral dose to establish Coxsackievirus B3(CVB3)-induced myocarditis murine model in different strains of mice,100TCID50 to 10 000TCID50 doses of CVB3 were intraperitoneally injected into sensitive BALB/c male mice and the non-sensitive C57BL/6mice.The severity of viral myocarditis was assessed by evaluation of weight loss,mortality,myocardial CK-MB level and cardiac pathology.1500TCID50 of CVB3was confirmed to be the best dosage to induce viral myocarditis in sensitive BALB/c male mice;and this virus dose also induced a much weaker but visible myocarditis in C57BL/6mice.Taken together,1500TCID50 dosage of CVB3 was demonstrated to be the best model-establishing dosage in BALB/c mice.Although C57BL/6mice is not a recommended strain for CVB3,1500TCID50 of CVB3still could induce myocarditis in these mice which may facilitate the research of viral myocarditis in most gene-knockout mice.Our data provide a very fundamental and key standard for the establishment of CVB3-viral myocarditis and facilitate the future study of this disease.