TGFB1 and systemic sclerosis: Our data also revealed that restoring KLF4 levels prevented TGFβ1-induced fibrogenesis in normal lung fibroblasts, and reduced fibrosis in explanted human lungs in organ culture.<h4>Conclusions</h4>Our results in human primary SSc lung fibroblasts showed that restoring KLF4 levels initiated dedifferentiation of fibrotic and inflammatory fibroblasts towards the phenotype of alveolar fibroblasts, their lineage precursors, highlighting the potential of KLF4 as a therapy to stop and reverse fibrosis.