Connective tissue growth factor expression in rabbit corneal fibroblast and its effect on fibroblast proliferationIn vitro

Abstract

The connective tissue growth factor (CTGF) expression in cultured corneal fibroblasts and its effect on corneal fibroblasts proliferationin vitro were examined. Total RNA was extracted from early passaged rabbit corneal fibroblasts by guanidine isothiocyanate one-step method and mRNA was reversely transcripted into complementary DNA (cDNA). Specific CTGF primers were used in the PCR reaction and the products were analyzed by electrophoresis to determine the expression of mRNA for CTGF against DNA marker. House-keeping gene GAPDH was used as control. Different concentrations of CTGF (0.5, 5, 50, 500, 5 000, 50 000 ng/ml) were added into the third passaged corneal fibroblast culture system, and its effect on corneal fibroblast proliferation was measured by MTT method. The results showed that compared with a GAPDH 450 bp band, CTGF RT-PCR product showed a specific 120 bp band as expected. CTGF produced a dose-dependent increase in the proliferation of corneal fibroblasts but it inhibited fibroblast proliferation at higher concentrations (5000 and 50 000 ng/ml). It was concluded that proliferating corneal fibroblasts produce CTGF and CTGF helps to promote corneal fibroblast proliferation. The results indicated that CTGF might be involved in the corneal wound healing after photorefractive keratectomy in which corneal fibroblasts are activated to proliferate and secrete growth factors that in turn promote corneal fibroblast proliferation.

Keywords

connective tissue growth factor / corneal fibroblasts / expression / proliferation / rabbit

References

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