| PurposeProliferative vitreoretinopathy (PVR) is an excessive repair in response to injury, which involves many kinds of inflammatory factors, inflammatory cells and intraocular cells. And there is imbalance between proliferation and death of cells in the development of PVR. Retinal pigment epithelium (RPE) cells are predominant proliferative cells in PVR. But the pathogenesis of PVR remains poorly understood. Consequently, study on the regulations of proliferation and apoptosis of RPE cells is important to the prevention and treatment of PVR and other related eye diseases. Syndecan-1 is a member of heparan sulfate proteoglycans (HSPG), and it binds to extracellular ligands bearing heparan sulfate. It has been proposed to h-ave roles in cellular and extracellular matrix adhesion, cell phenot-ype differentiation and migration. Survivin is a newly discovered inhibitor of apoptosis protein (IAP), highly expressed during development and in most human cancers, while almost silent in most n-ormal, terminally differentiated adult tissues. Till now, it is the strongest inhibitor of apoptosis. Its function includes promoting proliferation, inhibiting apoptosis, modulating mitosis and angiogenes-is. So far, no research paper has reported on the expression and ef-fects of syndecan-1 and survivin on RPE cells.This study aimed: (1) to investigate the expression of syndecan-1 in proliferative membranes obtained from eyes with retinal detachment and PVR, the expression of syndecan-1 in cultured human RPE cells after exposed to different stimulating factors and related signal pathway, and the influence of syndecan-1 expression changes to RPE cellular adhesion, (2) to study the expression of survivin in periretinal membranes of PVR, expression of survivin in culture-d RPE cells, and effects of survivin antisense oligonucleotide (AS-ON) on RPE cell proliferation and apoptosis. Methods1. (1) Periretinal membranes obtained from cases of PVR with retinal detachment undergoing vitrectomy were used to examine the expression of syndecan-1 by immunohistochemical staining, and t-he normal retina from the eyeball after cornea grafting were detected by immunohistochemical and immunofluorescence staining. (2) Immunofluorescence staining and reverse transcription polymerase chain reaction (RT-PCR) were used to test the expression of syndecan-1 protein and its mRNA in cultured unstimulated RPE cells. T-he expression of syndecan-1 was detected and quantitatively analyzed by image process of immunofluorescence. Several stimulants were involved, including tumor necrosis factor (TNF)- a with two concentrations (7, 35 ng/ml) for 24 h, lipopolysaccharide (LPS) with two concentrations (1, 6 ug/ml) for 11 h, TNF- a with the concentration of 7 ng/ml for distinct times (0~24 h, once per 2 h, 13 times in total), 30% supernatant of THP-1 cells for 3 h, 14 h and 43 h. The effect of 30% supernatant of THP-1 cells was assayed after 2 kinds of MAPK pathway inhibitors (PD098059, SB202474) were used for 2 h. (3) After exposed to 30% supernatant of THP-1 cells for 3 h, 0.25% trypsin was used for 5 min, and adhesion of RPEcells was evaluated by MTT assay.2. (1)Immunohistochemical staining was used to examine the expression of survivin in proliferative membranes of PVR. (2) The expression of survivin protein and its mRNA was detected in cultured RPE cells by immunohistochemical staining and RT-PCR. After cultured with different concentrations of survivin antisense oligon-ucleotide (ASON) for 6 h, the ASON-DMEM mixture was replaced with DMEM of 10% fetal calf serum, and RPE cells were cultured for additional 19 h. The morphologic changes of cells were observed by light microscopy and HE staining. Proliferation and apoptos-is in RPE cells were evaluated using MTT assay and flow cytomet-er. Results1. (1) In the normal retina, RPE layer, the inner and outer nuclear layers showed strong syndecan-1 staining, inner segments of photoreceptor, inner and outer plexiform layer, ganglion cell layer and retinal neural fibers showed medium staining. Syndecan-1 w...
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