Tacrolimus Inhibits Human Tenon’s Fibroblast Migration, Proliferation, and Transdifferentiation

<b>Background/Objectives</b>: We aimed to investigate the effects of tacrolimus on human Tenon's fibroblast (HTF) migration, proliferation, and transdifferentiation in vitro. <b>Methods</b>: HTF cells were subcultured and serum-starved for 24 h before being treated with 10 ng/mL tacrolimus. After 1 h, 30 ng/mL platelet-derived growth factor (PDGF) or 10 ng/mL transforming growth factor beta-1 (TGF-β1) was administered to the HTFs. Migration, proliferation, and transdifferentiation were assessed using WST-1 assays, scratch-induced directional wounding, and western blot analysis. The involvement of the TGF-β signaling pathway was examined via western blotting to measure phosphorylated Smad2, Smad3, ERK, and Akt levels. <b>Results</b>: TGF-β1 and PDGF enhanced HTF migration, proliferation, and transdifferentiation, whereas tacrolimus inhibited these effects. Tacrolimus also inhibited the TGF-β1-induced upregulation of phosphorylated Smad2 and Smad3, suggesting its inhibitory effects occur through TGF-β1 signaling. <b>Conclusions</b>: Overall, tacrolimus can inhibit PDGF- and TGF-β1-induced HTF migration, proliferation, and transdifferentiation, primarily through the Smad-dependent TGF-β signaling pathway. To develop a new therapeutic modality, further longitudinal in vivo studies and human clinical trials are warranted.