The Expression Of Interleukin-10 In Fungal Keratitis In Rats

Objective:To observe the expression of Interleukin-10 (IL-10) and Cycyclooxygenase (COX-2) in fungal keratitis and study the effect of COX-2 selective inhibitor NS-398 on the expression of IL-10 in fungal keratitis in rat, then analysis their effects on anti-fungus immunity.Materials and methods:85 Wistar rats were randomly divided into 3 groups, Group A was blank control group (5 eyes). Group B was fungal keratitis group (40 eyes). Group C was fungal keratitis group treated by NS-398 (40 eyes). After epithelium of central cornea were scraped, Fusarium solani-laden contact lenses were covered in right corneas of group B and C, the left cornea covered with contact lenses as the control eyes. The expression of IL-10 and COX-2 in corneas of group B and C (at 1d,3d,7d,14d) were detected by inmmunohistochemistry and semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR).Results:Histopathologic examination showed neutrophil and severe tissue necrosis in ulcered cornea. PAS staining confirmed the exsistence of hyhae and spores in the superficial and middle layer of stroma.2. Almost no expression of COX-2 were detected in the blank control group and the control eyes at any observing points. In the experimental group, the expression of COX-2 could be detected at the first day after infection, the level of COX-2 increased with the time-lapse, but to the 14d of infection COX-2 shows a particularly low expression. The expression of COX-2 showed the significant difference at any observing points (P<0.01). Compared with group B ,group C showed a significant decline of COX-2 expression in 3d,7d after infection, but showed no difference in 1d and 14d between them. 3. In the blank control group and the control group almost no expression of IL-10 were detected at any observing points. The expression of IL-10 showed a increasing at first and then decreased. The expression of IL-10 showed the significant difference at any observing points (P<0.01). Compared with group B, the expression of IL-10 in group C showed no difference at Id, decrease at 3d, but a significant increase at 7d and 14d.Conclusion:1. PAS stain,10% potassium hydroxide (KOH) smear and fungal culture confirmed the successful establish of fungal keratitis mode. 2. COX-2 were sensitive factors in fungal keratitis, NS-398 can inhibit the expression of COX-2.3. IL-10 takes part in the occurrence and development of fungal keratitis, NS-398 can up the expression of IL-10 in fungal keratitis. Even in the later period of the ulcer, expression of IL-10 still at a high level, meanwhile, pathologic observation showed a slightly corneal opacity, IL-10 may play an important role in the process of cornea anti-damage repair.