['Fibroblast heterogeneity is recognized, and fibroblasts from diseased tissues, including those of asthmatic subjects, have functional phenotypes that differ from normal\xa0tissue. However, progenitor-progeny relationships and the factors that control fibroblast differentiation are poorly defined.', 'We sought to determine whether IL-4 could alter the functional phenotype of fibroblasts during their differentiation from stem/progenitor cells.', 'Using a 3-dimensional collagen gel system, we obtained embryoid bodies derived from human embryonic stem cells and recovered spindle-shaped cells consistent with fibroblasts that had differentiated in the presence or absence of IL-4.', 'IL-4-induced fibroblast-like cells were more active in contraction of collagen gels, migration, and production of fibronectin than control (without IL-4) cells. IL-4-induced cells demonstrated less expression of miR-155, which modulated contraction, migration, and fibronectin production. These differences persisted in culture without further addition of IL-4, suggesting the differentiated phenotype might be a permanent alteration.'] Does iL-4 induce differentiation of human embryonic stem cells into fibrogenic fibroblast-like cells?