Growth factor responsiveness of human retinal pigment epithelial cells.
Growth factor effects on DNA synthesis in density-arrested human retinal pigment epithelial cells were assessed by [3H]-thymidine incorporation. Acidic and basic fibroblast growth factor and epidermal growth factor were potent stimulators, whereas platelet-derived growth factor, insulinlike growth factor-1, and insulin were weak or modest stimulators when used alone. When used in combination, each of the above growth factors caused a significant enhancement of [3H]-thymidine incorporation regardless of its effect when used alone. The combination of all four growth factors was significantly more effective than all other combinations, demonstrating synergism in their action. Similar results were found in cell proliferation assays. In contrast to this, transforming growth factor-beta inhibited the ability of each of the other growth factors and serum-containing media to stimulate [3H]-thymidine incorporation. These data suggest that DNA synthesis in human retinal pigment epithelial cells can be modulated by several growth factors, some in a stimulatory or synergistic manner and at least one in an inhibitory manner. A better understanding of these complex interactions may provide insights relevant to normal and abnormal ocular wound healing.
Department of Ophthalmology, University of Virginia Health Sciences Center, Charlottesville 22908.
K H
KH
Leschey
S F
SF
Hackett
J H
JH
Singer
P A
PA
Campochiaro
D002478:Cells, Cultured; D004247:DNA / Q000096:biosynthesis; D004357:Drug Synergism; D004815:Epidermal Growth Factor / Q000494:pharmacology; D005346:Fibroblast Growth Factors / Q000494:pharmacology; D006133:Growth Substances / Q000494:pharmacology*; D006801:Humans; D007328:Insulin / Q000494:pharmacology; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology; D010857:Pigment Epithelium of Eye / Q000187:drug effects* / Q000378:metabolism; D010982:Platelet-Derived Growth Factor / Q000494:pharmacology; D014168:Transferrin / Q000494:pharmacology; D015291:Transforming Growth Factors / Q000494:pharmacology
D006133:Growth Substances; D007328:Insulin; D010982:Platelet-Derived Growth Factor; D014168:Transferrin; D005346:Fibroblast Growth Factors; D004815:Epidermal Growth Factor; D007334:Insulin-Like Growth Factor I; D015291:Transforming Growth Factors; D004247:DNA