RARB and fatty liver disease: To elucidate whether AC261066, a selective RARβ2 agonist (13), limits liver steatosis via RARβ in hepatocytes, we examined AC261066’s effects on lipid accumulation in parental and RARβ knockout (RARβ KO) HepG2 cells generated using CRISPR/Cas9 technology (Fig. 5A).