TGFB1 and pemphigus foliaceus: Gazdhar et al. (2014) collected iPSC-conditioned media (iPSC-cm) from cultured iPSCs derived from human foreskin fibroblasts. Their research showed iPSC-cm increased alveolar epithelial wound repair in vitro and attenuated bleomycin-induced fibrosis in vivo, which may be a promising novel, cell-free therapeutic option against lung injury and fibrosis. Further studies demonstrated that the improved function of iPSC-cm in PF may be achieved by blocking the role of the TGF-β1/drosophila mothers against the decapentaplegic (Smad) signal transduction pathway (Zhou et al., 2018).