Journal Article

STAT3 activity is necessary and sufficient for the development of immune‐mediated myocarditis in mice and promotes progression to dilated cardiomyopathy

Jensen, Ole, Heymans, Stephane, Fletcher, Steven, Gunning, Patrick, Poli, Valeria, Chiarle, Roberto, Levi, Renzo, Carai, Paolo, Fornero, Sara, Papageorgiou, Anna, Marino, Francesca, Page, Brent D. G., Camporeale, Annalisa, Forni, Marco, Morello, Mara

2013

Overview

Myocarditis, often triggered by viral infection, may lead to heart auto‐immunity and dilated cardiomyopathy. What determines the switch between disease resolution and progression is however incompletely understood. We show that pharmacological inhibition of STAT3, the main mediator of IL‐6 signalling and of Th17‐cell differentiation, protects mice from the development of Experimental Auto‐immune Myocarditis reducing liver production of the complement component C3, and can act therapeutically when administered at disease peak. Further, we demonstrate that STAT3 is sufficient when constitutively active for triggering the onset of immune‐mediated myocarditis, involving enhanced complement C3 production and IL‐6 signalling amplification in the liver. Disease development can be prevented by C3 depletion and IL‐6 receptor neutralization. This appears to be relevant to disease pathogenesis in humans, since acute myocarditis patients display significantly elevated circulating IL‐6 and C3 levels and activated heart STAT3. Thus, aberrant IL‐6/STAT3‐mediated induction of liver acute phase response genes including C3, which occurs as a consequence of pre‐existing inflammatory conditions, might represent an important factor determining the degree of myocarditis and its clinical outcome. Graphical Abstract Aberrant IL‐6/STAT3‐mediated induction of liver acute phase response genes including C3, a consequence of pre‐existing inflammatory conditions, is involved in determining the degree of myocarditis and its clinical outcome.

• Publisher: Nature Publishing Group UK,WILEY‐VCH Verlag,EMBO Press,WILEY-VCH Verlag,Springer Nature
• Subject: Animals / Cardiomyopathy / Cardiomyopathy, Dilated - genetics / Cardiomyopathy, Dilated - immunology / CD4-Positive T-Lymphocytes - microbiology / Cell differentiation / complement C3 / Complement C3 - immunology / Complement component C3 / Dilated cardiomyopathy / Disease / Disease Progression / experimental autoimmune myocarditis / Experiments / Female / Heart attacks / Heart diseases / Heart failure / Helper cells / Humans / immune‐mediated myocarditis / Inflammation / Interleukin-6 - genetics / Interleukin-6 - immunology / interleukin‐6 / Liver / Liver - immunology / Liver diseases / Lymphocytes / Lymphocytes T / Male / Mass spectrometry / Medical research / Mice / Mice, Inbred BALB C / Myocarditis / Myocarditis - genetics / Myocarditis - immunology / Pathogenesis / Proteins / Research Article / Scientific imaging / STAT3 / Stat3 protein / STAT3 Transcription Factor - genetics / STAT3 Transcription Factor - immunology / Th17 Cells - immunology / Transcription factors / Variance analysis