DNMT3A clonal hematopoiesis-driver mutations induce cardiac fibrosis by paracrine activation of fibroblasts

Hematopoietic mutations in epigenetic regulators like DNA methyltransferase 3 alpha (DNMT3A) drive clonal hematopoiesis of indeterminate potential (CHIP) and are associated with adverse prognosis in patients with heart failure (HF). The interactions between CHIP-mutated cells and other cardiac cell types remain unknown. Here, we identify fibroblasts as potential interaction partners of CHIP-mutated monocytes using combined transcriptomic data from peripheral blood mononuclear cells of HF patients with and without CHIP and cardiac tissue. We demonstrate that DNMT3A inactivation augments macrophage-to-cardiac fibroblasts interactions and induces cardiac fibrosis in mice and humans. Mechanistically, DNMT3A inactivation increases the release of heparin-binding epidermal growth factor (EGF)-like growth factor (HB-EGF) to activate cardiac fibroblasts. These findings not only identify a novel pathway of DNMT3A CHIP-driver mutation-induced instigation and progression of HF, but may also provide a rationale for the development of new anti-fibrotic strategies.