MYH14 and rheumatic heart disease: Davies (33) and Fourneau et al. (35) pointed out that antigens such as myosin and actin that dominate the late immune response in RHD/AM need not be the antigens that initiate autoimmunity; epitope spreading may occur in which one host protein is the initial target of an autoimmune response, the result of which is release of hidden host antigens that then come to dominate subsequent autoimmunity.