EFFECT OF CYTOKINES AND PROSTAGLANDINS ON THE GROWTH OF CHICK RETINAL-PIGMENT EPITHELIAL-CELLS

The effect of cytokines and prostaglandins on the growth of chick reti nal pigment epithelial (RPE) cells was studied in vitro. The growth of RPE cells was evaluated by [H-3]-thymidine uptake. Human recombinant interleukin-1 beta, interferon-beta and tumor necrosis factor-alpha st imulated the growth of RPE cells at 50-200 units/ml. Prostaglandins su ch as PGE(1), PGE(2) and PGF(2 alpha) suppressed RPE cell. growth at 1 0(-5 similar to -6) M. Indomethacin, an inhibitor of cyclooxygenase, d id not affect the spontaneous RPE cell growth at 10(-7 similar to -9) M. However, 10(-7) M indomethacin enhanced RPE cell growth stimulated by cytokines synergistically. The addition of 10(-6) M PGF(2 alpha) su ppressed the enhanced growth of RPE cells which was induced with cytok ines and indomethacin. Furthermore, RPE cells stimulated with cytokine s produced PGE(2). These results suggest that RPE cells produce prosta glandins which have a negative regulatory role in RPE cell growth.