98th Annual Meeting DOG 2000

P 11

Synthesis of extracellular matrix proteins in iris pigment epithelial cells and retinal pigment epithelial cells in vitro

A. Lappas, T. Berndt, A. M. H. Foerster, B. Kirchhof

Introduction: Iris pigment epithelial cells (IPE) have been proposed for transplantation into the subretinal space as alternative to retinal pigment epithelial calls (RPE). Some functional similarities between the two cell types concerning phagocytosis could be demonstrated. In our study we compared the expression of extracellular matrix proteins in vitro.

Methods: Porcine IPE and RPE cells were isolated and cultivated in chamber slides. After 4 weeks they were fixed in methanol and treated with anti fibronectin, anti laminin, anti collagen I and anti collagen IV antibodies. After incubation with a fluorescent secondary antibody the cells were examined under a fluoresence microscope.

Results: After four weeks cultivated IPE and RPE cells formed a confluent layer and displayed their differentiated pigmentation. Positive fluoresence could be observed after incubation with anti fibronectin, anti laminin and anti collagen I antibodies in both cell types. When treated with anti collagen IV only RPE cells showed positive fluoresence.

Conclusion: Fibronectin, laminin and collagen I could be detected in RPE and IPE cells in vitro. Collagen IV was only found in RPE cells. In vivo studies should be performed to examine the relevance of production of extracellular matrix proteins after cellular transplantation.

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