Multimodal CRISPR perturbations of GWAS loci associated with coronary artery disease in vascular endothelial cells.

Genome-wide association studies have identified >250 genetic variants associated with coronary artery disease (CAD), but the causal variants, genes and molecular mechanisms remain unknown at most loci. We performed pooled CRISPR screens to test the impact of sequences at or near CAD-associated genetic variants on vascular endothelial cell functions. Using CRISPR knockout, inhibition and activation, we targeted 1998 variants at 83 CAD loci to assess their effect on three adhesion proteins (E-selectin, ICAM1, VCAM1) and three key endothelial functions (nitric oxide and reactive oxygen species production, calcium signalling). At a false discovery rate ≤10%, we identified significant CRISPR perturbations near 42 variants located within 26 CAD loci. We used base editing to validate a putative causal variant in the promoter of the FES gene. Although a few of the loci include genes previously characterized in endothelial cells (e.g. AIDA, ARHGEF26, ADAMTS7), most are implicated in endothelial dysfunction for the first time. Detailed characterization of one of these new loci implicated the RNA helicase DHX38 in vascular endothelial cell senescence. While promising, our results also highlighted several limitations in using CRISPR perturbations to functionally dissect GWAS loci, including an unknown false negative rate and potential off-target effects.

Metabolic dysfunction-associated steatohepatitis exhibits sex differences in people with HIV.

OBJECTIVES: People with HIV are at increased risk for metabolic dysfunction-associated steatohepatitis (MASH). Although sex differences are documented in the general population, their role in the context of HIV is less understood. METHODS: This was a multicentre cohort study including people with HIV without viral hepatitis coinfection. A FibroScan-AST (FAST) score >0.35 was used to diagnose MASH with significant liver fibrosis (stage F2-F4). We investigated sex-based differences in MASH trends as a function of age using a segmented linear mixed-effects model. Random effects accounted for clustering by the four sites. Adjusted models included ethnicity, diabetes, hypertension, and detectable HIV viral load. RESULTS: We included 1472 people with HIV (25% women). At baseline, the prevalence of MASH with fibrosis by FAST score was lower in women than in men (4.8% vs. 9.2%, p = 0.008). Based on the adjusted model, male sex (+0.034; p = 0.04), age per year (+0.003; p = 0.05), detectable HIV viral load (+0.034; p = 0.02), and hypertension (+0.03; p = 0.01) were positively associated with MASH with fibrosis. Although men exhibited generally higher FAST scores, FAST scores increased in women during the critical biological age of presumed perimenopause to menopause (between 40 and 50 years), reaching levels similar to those in men by the age of 55 years. CONCLUSION: Despite women with HIV having a lower prevalence of MASH with fibrosis than men, they exhibit an acceleration in FAST score increase around the perimenopausal age. Future studies should target adequate consideration of sex differences in clinical investigation of metabolic dysfunction-associated steatotic liver disease to fill current gaps and implement precision medicine for people with HIV.