Endotoxin-induced production of inflammatory mediators by cultured ciliary epithelial cells

Systemic injection of bacterial endotoxin (Lipopolysaccharide, LPS) in experimental animals induces anterior uveitis without major pathological changes in other organs. The present study investigates the effect of LPS on production of inflammatory mediators in cultured bovine pigmented ciliary epithelial cells (CB-cells) by means of radioimmunoassays and bioassays. LPS was found to stimulate CB-cells to secrete prostaglandin E2 and prostacyclin (assayed as its stable metabolite 6-keto-prostaglandin F1a), but not leukotriene B4 or thromboxane A2 (assayed as its stable metabolite thromboxane B2). CB-cells produced membrane-associated interleukin 1-activity in response to LPS, but no tumor necrosis factor-activity was found after challenge of CB-cells with LPS. The direct effect of LPS on production of inflammatory mediators by cells from the anterior uvea could play a role in the pathophysiology of endotoxin-induced uveitis.