CRISPR/Cas9-induced chemR23 knock-out improves arterial inflammation in atherosclerotic mice

Emerging evidence implicates chemerin, a chemoattractant protein, in the pathogenesis of atherosclerosis (AS). Yet, the role of its receptor, Chemokine-Like Receptor 1 (ChemR23), in AS remains enigmatic. Leveraging CRISPR/Cas9 genome editing, this study delineates the impact of ChemR23 ablation in an AS murine model, aiming to unravel its mechanistic involvement in AS pathophysiology.

Employing CRISPR/Cas9, we orchestrated a targeted knockout of the ChemR23 gene in C57BL/6J wild-type (WT) mice, followed by an eight-month high-fat dietary regimen. High-fat diet-fed WT mice and their standard diet counterparts constituted the experimental and baseline cohorts, respectively. We deployed commercial assay kits to quantify lipid metabolism markers and inflammatory mediators. Histopathological changes in arterial plaques and lipid deposition were appraised using Hematoxylin & Eosin and Oil Red O staining. Western blotting, Immunohistochemistry, and Immunofluorescence staining were harnessed to interrogate plaque inflammatory signaling and autophagy-related protein expression. Macrophage polarization dynamics were dissected via flow cytometry, and foam cell gene expression profiles were ascertained through quantitative real-time PCR.

ChemR23 knockout conferred ameliorative effects on lipid metabolic aberrations and plaque stability in AS mice, evidenced by diminished lipid accrual in plaques. It attenuated the activation of the NF-κB inflammatory cascade, fostered an M2 macrophage polarization bias, and impeded the macrophage-to-foam cell transition. Notably, ChemR23 ablation suppressed autophagic activities within the plaques.

Targeted ChemR23 gene disruption in mice manifests as a modulator of inflammatory and autophagic pathways, thereby mitigating AS exacerbation. This positions ChemR23 as a promising molecular candidate for strategic AS therapeutics.