CTLA4 and idiopathic dilated cardiomyopathy: As expected, acute cases of giant cell myocarditis (Figure 7C) also showed intense CTLA4 expression (average percentage of CTLA-4+ cells/total infiltrating cells counted = 11,5±8; range = 1–24% in 10 representative fields per patient), whereas CTLA-4+ cells were not detected in idiopathic dilated cardiomyopathy where inflammation was not apparent (Figure 7D), confirming the association between the presence of inflammation and CTLA-4 expression.