Suppression of IL-1ß promotes beneficial accumulation of fibroblast-like cells in atherosclerotic plaques in clonal hematopoiesis [scRNA-Seq]

Clonal hematopoiesis (CH) is an independent risk factor for atherosclerotic cardiovascular disease. Murine models of CH suggest a central role of inflammasomes and IL-1ß in accelerated atherosclerosis and plaque destabilization. Here we show using scRNAseq in human carotid plaques that inflammasome components are enriched in macrophages, while the receptor for IL-1ß is enriched in fibroblasts and smooth muscle cells (SMCs). To address the role of inflammatory crosstalk in features of plaque destabilization, we conducted SMC fate mapping in mice modeling Jak2VF or Tet2 CH treated with IL-1ß antibodies. Unexpectedly, this treatment minimally affected SMC differentiation, leading instead to a prominent expansion of fibroblast-like cells. Depletion of fibroblasts from mice treated with IL-1ß antibody resulted in thinner fibrous caps. Conversely, genetic inactivation of Jak2VF during plaque regression promoted fibroblasts accumulation and fibrous cap thickening. Our studies suggest that suppression of inflammasomes promotes plaque stabilization by recruiting fibroblast-like cells to the fibrous cap. Overall design: 20% Jak2VF or cx3cr1-Cre Tet2 fl/fl bone marrow mixed with 80% WT bone marrow was tranplanted into Ldlr-/- with a Myh11-Cre driven Zsgreen1 reporter. Mice were pulsed with tamoxifen, then put on a western diet for the last 6 weeks of diet mice were given IgG or IL-1b antibodies