Effects of TGFβ1, PDGF-BB, and bFGF, on human corneal fibroblasts proliferation and differentiation during stromal repair

In an effort to improve the regenerative nature of corneal repair, this study reports the use of an in vitro human corneal fibroblasts (HCFs) wound model after treatment with three of the main growth factors (GFs) involved in corneal healing: transforming growth factor beta 1 (TGF131), platelet-derived growth factor BB-isoform (PDGF-BB), and basic fibroblast growth factor (bFGF) in order to delve in cell proliferation and differentiation processes. HCFs were mechanically wounded. The individual effect of TGF beta 1., PDGF-BB, and bFGF on cell proliferation and differentiation during the repair process was studied at different time points until wound closure. Wound dimensions and morphological changes were evaluated by microscopy. Cell proliferation and myofibroblast differentiation were analyzed by immunofluorescence cytochemistry. Changes in cell morphology were apparent at Day 4. PDGF-BB- and bFGF-treated cells had fibroblast-like morphology. TGF beta 1 stimulated proliferation in the wound edge and surrounding area, induced myofibroblast differentiation and inhibited cellular migration. PDGF-BB induced rapid wound closure due to proliferation, high motility, and late myofibroblast differentiation. The time course of closure induced by bFGF was similar to that for PDGF-BB, but was mostly due to proliferation in the wound area, and inhibited myofibroblast differentiation. Each of the GFs induced increases in responses promoting stromal repair differently. This study provides insight regarding how to optimize the outcome of stromal repair following corneal injury.