Effect of prophylactically applied CpG ODN on the development of myocarditis in mice infected with Coxsackievirus B3

► CpG ODN at 10 μg/mouse inhibited the CVB3 replication in the hearts of mice. ► CpG ODN at 10 μg/mouse increased the production of CVB3 neutralizing antibody. ► CpG ODN at 20 μg/mouse reduced the level of CVB3 neutralizing antibody. ► CpG ODN at 20 μg/mouse increased the TLR9 expression in the hearts of mice.