Objective To investigate the modulating effect of transforming growth factor  beta;2 (TGF beta;2) and extracellular matrix (ECM) on the transdifferentiation of human fetal RPE (hfRPE) cells into myofibroblast-like cells , and to determine the mechanism of signal transduction. Methods hfRPE cells were cultured on ECM coated or uncoated petri dish with or witho ut TGF beta;2 in the medium. The expression of  alpha;-smooth muscle actin ( alpha;-SMA) were detected by immunocytochemistry examination, flow cytometry and Western blotting via calphostin C, genistein, PD98059, and Wortmannin. Results After cultured on ECM coated petri dish with TGF beta;2 in the medium,there were obvious morphological changes of hfRPE cells including cellular elongating and appearing of actin microfilaments. The results of flow cytometry and immunocytochemistry examination showed that expression of  alpha;-SMA obviously increased after TGF beta;2 was added in the medium in a dose-dependent manner. Compared with which of hfRPE cells cultured on the uncoated surface of culture plates, the total mean fluore scence intensity (TMFI) of hfRPE cells cultured on FN-coated surface increased (38.01 plusmn;1.14)% when the stimulation concentration of TGF beta;2 was 50ng/ml(P lt;0.05). Western blotting further confirmed the effects. The changes mentioned above could be inhibited mostly by protein kinase C (PKC) and calphostin C (10 nmol/L)(P lt;0.01). Conclusion TGF beta;2 may induce the transdifferentiation of hfRPE cells into myofibroblast-like cells in a dose dependent manner, which could be intensified by FN. These mediated effects of TGF beta;2 and ECM may act via the PKC signal transduction pathway.  (Chin J Ocul Fundus Dis, 2006, 22: 328-332)

Citation： CHEN Youxin,HE Shikun. Transdifferentiation of retinal pigment epithelial cells into myofibroblast-like cells induced by the conjunct action of extracellular matrix protein and transforming growth factor β2. Chinese Journal of Ocular Fundus Diseases, 2006, 22(5): 328-332. doi: Copy