NR1H3 and idiopathic pulmonary fibrosis: Normal and IPF fibroblasts constitutively expressed similar levels of ARG2 mRNA; however, only IPF fibroblasts showed higher expression of ARG2 after stimulation with LXR agonist GW3965 (Fig 5, F) and this increased ARG2 expression was attenuated by transfection with LXRα siRNA (Fig 5, G).