Type I interferon responses to ischemic injury begin in the bone marrow of mice and humans and depend on Tet2, Nrf2, and Irf3

Abstract

Sterile tissue injury locally activates innate immune responses via interactions with damage associated molecular patterns (DAMPs). Here, by analyzing [~]120K single cell transcriptomes after myocardial infarction (MI) in mice and humans, we show neutrophil and monocyte subsets induce type I interferon (IFN) stimulated genes (ISGs) in myeloid progenitors of the bone marrow, far from the site of injury. In patients with acute MI, peripheral blood neutrophils and monocytes express ISGs at levels far beyond healthy individuals and comparable to patients with lupus. In the bone marrow of Tet2-/- mice, ISGs are spontaneously induced in myeloid progenitors and their progeny. In the heart, IFN responses are negatively regulated by Ccr2- resident macrophages in a Nrf2-dependent fashion. Our results show post-MI IFN signaling begins in the bone marrow, implicate multiple transcription factors in its regulation (Tet2, Irf3, Nrf2), and provide a clinical biomarker (ISG score) for studying post-MI IFN signaling in patients.