TGFB1 and pemphigus foliaceus: TGF-β is the most potent pro-fibrotic mediator, inducing ECM, EMT, and pro-fibrotic mediators’ production by promoting the binding of Smad2/3 to Smad4, and driving myofibroblast differentiation to promote the PF process (Hu et al., 2018; Kramer and Clancy, 2018).