Our data, together with data from other groups, strongly suggest that caveolin-1 is a key signaling molecule in the monocyte-fibrocyte-fibroblast lineage and is responsible for functional differences observed among cells isolated from SSc-ILD and idiopathic pulmonary fibrosis (IPF) patients compared to control subjects [14-16]. The gene discussed is CAV1; the disease is idiopathic pulmonary fibrosis.