Purification and Transcriptomic Characterization of Hypertrophied Hepatic Stellate Cells From CDAHFD Mouse Liver

Hepatic stellate cells (HSC) are known for their major role in hepatic fibrosis. It is well established that upon liver injury, they undergo a transition from a quiescent state to an activated state and transdifferentiate into proliferative, fibrogenic myofibroblasts. Recently, it has been shown that different subpopulations of HSC co-exist during fibrogenesis and play different roles in the establishment of fibrosis. We previously highlighted, in murine model and human biopsies, a specific subpopulation of hypertrophied HSC (hypHSC) which exhibits exacerbated retinoid droplets and were closely associated with collagen fibers. The present study focuses on the molecular characterization of hypHSCs isolated from a murine model of metabolic liver fibrosis thanks to an experimental strategy we developed and described here. Liver dissociation followed by density gradient and fluorescence assisted cell sorting allowed us to obtain highly pure hypHSC preparations. Then, a transcriptomic analysis (bulk RNAseq) of hypHSCs versus quiescent HSCs purified from healthy mouse liver was performed. This showed that hypHSCs' molecular signature differs from HSC subtypes already described in the literature, with a "hybrid" profile involved in the regulation of the immune system, the remodeling of extracellular matrix and exhibiting a deregulation of lipid metabolism. Our study highlights that a phenotype-to-molecular approach can provide complementary elements to single-cell molecular approaches and provides additional insights into the plasticity of hepatic stellate cells in a context of hepatic fibrosis.