The pathogenesis of polypoidal choroidal vasculopathy (PCV) is still controversial. More evidence of clinical and basic research is needed to distinguish PCV from an independent disease to a subtype of age-related macular degeneration. Not only that, there are also many puzzles in the diagnosis, treatment options and prognosis of PCV. In addition to these common problems, we also face a large population with risk factors, a large number of PCV patients with multiple and complex challenges in China. There is a long way to go to reduce the damage effects of PCV on visual function. To fulfil this goal, we need make full use of the huge resources of PCV patients and turn these challenges into opportunities, and contribute the improvement of diagnosis and better understanding of PCV pathogenesis.
Objective To investigate the modulating effect of transforming growth factor beta;2 (TGFbeta;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 TGFbeta;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 TGFbeta;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 TGFbeta;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 (38.01plusmn;1.14)% when the stimulation concentration of TGFbeta;2 was 50ng/ml(Plt;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)(Plt;0.01). Conclusion TGFbeta;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 TGFbeta;2 and ECM may act via the PKC signal transduction pathway. (Chin J Ocul Fundus Dis, 2006, 22: 328-332)
Autofluorescence is produced by lipofuscin in retinal pigment epithelium (RPE) cells which is induced by exciting light and enables the visualization of lipofuscin changes in the RPE cells, thus showing the function of RPE and photoreceptor cells. Fundus autofluorescence (FAF) imaging is a non-invasive imaging technique providing information of RPE and photoreceptor cells, which is not obtainable with other imaging modalities. The scope of applications includes identification of diseased RPE in retinal diseases, elucidating pathophysiological mechanisms, estimating disease progression and prognosis, guiding treatment protocols. Common fundus diseases have different pathological types, levels and causes, so they can cause various damages of RPE and photoreceptor cells which induce complicated FAF. It is worth to further observing and investigating the common retinal diseases' FAF characteristics and clinical applications.