 TLR9 shows specific activity in post-heart attack fibroblasts, inducing them to differentiate into myofibroblasts and speed repair of left ventricle tissue.In contrast to pre-myocardial infarction, cardiomyocytes in recovering hearts do not induce an inflammation response via TLR9/NF-κB pathway.Instead, the pathway leads to proliferation and differentiation of fibroblasts.