STAT3 and idiopathic pulmonary fibrosis: Here, we provide a model where the increased sensitivity of mutant gp130757F receptors mediates cytokine-dependent Stat3 activation in mice akin to a smouldering asymptomatic inflammation triggered by prolonged intranasal administration of Osm to wild-type mice or excessive abundance of IL-6 or OSM associated with the pathogenesis of fibrosis in IPF patients (Lesur et al, 1994; Mozaffarian et al, 2008; Xing et al, 1994).