Age as a determinant factor for endotoxin induced uveitis

Purpose: To determine if susceptibility to systemic endotoxin-induced uveitis is an age-related phenomenon in the rabbit. Methods: Young and adult rabbits were injected intravenously with 2.5 μg/kg of E. coli endotoxin or saline. Thereafter, the number of exudating cells at 2, 6, 12, 24 and 48 hours were determined. The levels of lipopolysaccharide-binding protein, total protein, prostaglandin-E2, nitric oxide and interleukin-6 in aqueous humor were also determined 24 hours after the injections. Results: A significant increase in the number of exudating cells and the levels of lipopolysaccharide-binding protein, total protein, prostaglandin-E2 and nitric oxide in aqueous humor was observed only in adult rabbits 24 hours after endotoxin injection. No differences were observed in the increased IL-6 levels. Conclusions: Life stage seems to be a critical factor in developing an eye-inflammatory response induced by systemic endotoxin. This could be a consequence of a differential specific activation of the ocular immune response.