98th Annual Meeting DOG 2000

P 16

Thalidomide and prednisolone inhibit growth factor-induced human RPE cell proliferation in vitro

C. W. Spraul1, C. Kaven1, N. Zavazava2, G. K. Lang1, G. E Lang1

Purpose: Response to growth factors by the RPE may modulate the development and progression of age-related macular degeneration (AMD). The aim of the study was to examine the effect of thalidomide and prednisolone on growth factor-activated RPE cells.

Methods: Cultivated human RPE cells were stimulated with 10 ng/ml platelet-derived growth factor (PDGF), basic fibroblast growth factor (bFGF), or vascular endothelial growth factor (VEGF) for 24 hr. Afterwards, the cells were incubated for further 24 hr with either thalidomide (50 µg/ml) or prednisolone (100 ng/ml). RPE cell proliferation was determined by [³H]-thymidine incorporation.

Results: PDGF and bFGF significantly stimulated human RPE cell proliferation (p < 0.005), the value for VEGF-stimulation was not significant (p = 0.3). After addition of thalidomide to PDGF-stimulated cells no significant [³H]-thymidine incorporation was observed any more as compared to the control medium). bFGF-induced DNA synthesis was also decreased by thalidomide (p < 0.005), but significant [³H]-thymidine incorporation could still be observed as compared to the control medium. Prednisolone caused a stronger effects on the inhibition of growth factor-induced RPE cell proliferation with a reduction of [³H]-thymidine incorporation of PDGF-stimulated cells of about 90 % and of bFGF-stimulated cells of 77 % (p < 0.005).

Conclusion: The current study presents that the inhibitory properties of thalidomide and prednisolone remain even after growth factor-activation of the cells, which is a crucial event in the development and progression of AMD.

This study was supported by Herbert Funke Foundation in Berlin and a grant form the Deutsche Forschungsgemeinschaft (SP 494/3-1).
Department of Ophthalmology, University Eye Hospital and Clinic, University of Ulm, Prittwitzstrasse: 43, D-89075 Ulm, Germany;
Department of Immunology, University of Kiel, Olshausenstrasse: 40, D-24118 Kiel, Germany