Expression and regulation of ST2, an interleukin-1 receptor family member, in cardiomyocytes and myocardial infarction

Background-We identified an interleukin-1 receptor family member, ST2, as a gene markedly induced by mechanical strain in cardiac myocytes and hypothesized that ST2 participates in the acute myocardial response to stress and injury. Methods and Results-ST2 mRNA was induced in cardiac myocytes by mechanical strain (4.7 +/- 0.9-fold) and interleukin-1beta (2.0 +/- 0.2-fold). Promoter analysis revealed that the proximal and not the distal promoter of ST2 is responsible for transcriptional activation in cardiac myocytes by strain and interleukin-1beta. In mice subjected to coronary artery ligation, serum ST2 was transiently increased compared with unoperated controls (20.8 +/- 4.4 versus 0.8 +/- 0.8 ng/mL, P < 0.05). Soluble ST2 levels were increased in the serum of human patients (N = 69) 1 day after myocardial infarction and correlated positively with creatine kinase (r = 0.41, P < 0.001) and negatively with ejection fraction (P = 0.02). Conclusions-These data identify ST2 release in response to myocardial infarction and suggest a role for this innate immune receptor in myocardial injury.