Retinal pigment epithelial cells produce interleukin-1 beta and granulocyte-macrophage colony-stimulating factor in response to interleukin-1 alpha.
The retinal pigment epithelium (RPE) is clinically involved in diverse ocular inflammatory diseases. Because perturbed RPE cells produce a variety of inflammatory substances, RPE cells may play an integral part in these diseases. Interleukin-1 (IL-1) and granulocyte-macrophage colony-stimulating factor (GM-CSF) are pleiotropic cytokines with the ability to trigger numerous inflammatory responses. This report shows that cultured human RPE cells synthesize interleukin-1 beta (IL-1 beta) and GM-CSF in response to the potentially inflammatory cytokine, IL-1 alpha, but not to E. coli endotoxin. Control RPE cells made little or no mRNA or protein for either IL-1 beta or GM-CSF. Upon stimulation of the cells by IL-1 alpha, both IL-1 beta and GM-CSF mRNAs were readily apparent by 3 hours, persisted for over 24 hours, and were translated into immunologically detectable proteins. GM-CSF protein was secreted into the culture medium, whereas IL-1 beta protein remained cell associated. The IL-1 alpha-induced mRNA and protein production were inhibited by dexamethasone. These observations provide additional evidence that RPE cells are capable of playing a pivotal role during ocular inflammation.
Planck
S R
SR
Department of Ophthalmology, Casey Eye Institute, Oregon Health Sciences University, Portland 97201-4197.
Huang
X N
XN
Robertson
J E
JE
Rosenbaum
J T
JT
D015152:Blotting, Northern; D002478:Cells, Cultured; D003470:Culture Media; D003907:Dexamethasone / Q000494:pharmacology; D004731:Endotoxins / Q000494:pharmacology; D004926:Escherichia coli; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000037:antagonists & inhibitors / Q000096:biosynthesis* / Q000235:genetics; D006801:Humans; D007375:Interleukin-1 / Q000037:antagonists & inhibitors / Q000096:biosynthesis* / Q000235:genetics / Q000494:pharmacology; D010857:Pigment Epithelium of Eye / Q000276:immunology*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000187:drug effects
D003470:Culture Media; D004731:Endotoxins; D007375:Interleukin-1; D012333:RNA, Messenger; C044101:endotoxin, Escherichia coli; D003907:Dexamethasone; D016178:Granulocyte-Macrophage Colony-Stimulating Factor