Human corneal epithelial cell and fibroblast migration and growth factor secretion after rose bengal photodynamic therapy (RB-PDT) and the effect of conditioned medium

PurposeTo investigate human corneal epithelial cell and fibroblast migration and growth factor secretion after rose bengal photodynamic therapy (RB-PDT) and the effect of conditioned medium (CM).MethodsA human corneal epithelial cell line (HCE-T), human corneal fibroblasts (HCF) and keratoconus fibroblasts (KC-HCF) have been used. Twenty-four hours after RB-PDT (0.001% RB concentration, 565 nm wavelength illumination, 0.17 J/cm(2) fluence) cell migration rate using scratch assay and growth factor concentrations in the cell culture supernatant using ELISA have been determined. In addition, the effect of CM has been observed.ResultsRB-PDT significantly reduced migration rate in all cell types, compared to controls (p <= 0.02). Migration rate of HCE-T cultures without RB-PDT (untreated) was significantly higher using HCF CM after RB-PDT, than using HCF CM without RB-PDT (p<0.01). Similarly, untreated HCF displayed a significantly increased migration rate with HCE-T CM after RB-PDT, compared to HCE-T CM without treatment (p<0.01). Furthermore, illumination alone and RB-PDT significantly decreased keratinocyte growth factor (KGF) concentration in HCF and KC-HCF supernatant, and RB-PDT significantly decreased soluble N-Cadherin (SN-Cad) concentration in HCF supernatant, compared to controls (p<0.01 for all). In HCE-T CM, RB-PDT increased hepatocyte growth factor (HGF) and basic fibroblast growth factor (FGFb) concentration (p <= 0.02), while decreasing transforming growth factor beta (TGF-beta) concentration (p<0.01). FGFb concentration increased (p<0.0001) and TGF-beta concentration decreased (p<0.0001) in HCF CM, by RB-PDT. Epidermal growth factor (EGF), HGF, and TGF-beta concentration decreased (p <= 0.03) and FGFb concentration increased (p<0.01) in KC-HCF CM, using RB-PDT.ConclusionsHCE-T, HCF and KC-HCF migration rate is reduced 24 hours after RB-PDT. In contrast, HCE-T migration is enhanced using HCF CM after RB-PDT, and HCF migration rate is increased through HCE-T CM following RB-PDT. Modulation of EGF, KGF, HGF, FGFb, TGF-beta and N-Cadherin secretion through RB-PDT may play an important role in corneal wound healing.