Effect of cytokines and prostaglandins on the growth of chick retinal pigment epithelial cells.

Abstract

The effect of cytokines and prostaglandins on the growth of chick retinal pigment epithelial (RPE) cells was studied in vitro. The growth of RPE cells was evaluated by [3H]-thymidine uptake. Human recombinant interleukin-1 beta, interferon-beta and tumor necrosis factor-alpha stimulated the growth of RPE cells at 50-200 units/ml. Prostaglandins such as PGE1, PGE2 and PGF2 alpha suppressed RPE cell growth at 10(-5) approximately (-6)M. Indomethacin, an inhibitor of cyclooxygenase, did not affect the spontaneous RPE cell growth at 10(-7) approximately (-9) M. However, 10(-7) M indomethacin enhanced RPE cell growth stimulated by cytokines synergistically. The addition of 10(-6) M PGF2 alpha suppressed the enhanced growth of RPE cells which was induced with cytokines and indomethacin. Furthermore, RPE cells stimulated with cytokines produced PGE2. These results suggest that RPE cells produce prostaglandins which have a negative regulatory role in RPE cell growth.