The Correlation Studies Between TLR2,TLR4 And Inflammatory Response Of Rat Corneal Alkali Burn

Purpose: To observe the expressions of TLR2、TLR4 and inflammatory cytokine IL-1 beta and TNF alpha, and analysis the correlation between TLR2、TLR4 and inflammatory response on rat cornea alkali burn.Methods: 32 SPF SD(Sprague Dawley) healthy rats excluding anterior segment disease, the right eye as burn experiment and the left eye as normal control, established III level corneal alkali burn model with concentration of 1 mol/l Na OH, then were randomly grouped into 3 days, 7 days, 14 days and 21 days group, 8 eyes of each group. The rats were observed and photographed anterior segment in 3 days, 7 days, 14 days and 21 days, evaluated the corneal inflammation index, then removed the eyeball of the rats in the corresponding time points. The eyeballs were made into pathological tissue section and stained with HE method, then observed the pathological changes of the cornea. The number of inflammatory cells in the cornea was calculated, and the expression of TLR2、TLR4、IL- 1 beta and TNF alpha was detected in the rat cornea with protein imprinting method at the same time. The differences of each group were analysised, and the correlation was assessed between TLRs and inflammatory factor.Results: 1. The inflammation index of 3 days, 7 days, 14 days and 21 days in the rat cornea was respectively(0.750 ±0.051),(0.820±0.057),(0.639 ± 0.078), and(0.264 ± 0.057), the difference was statistically significant(P < 0.05). The inflammatory cell numbers of each group in the rat cornea were(71.00 ±2.646),(90.33±1.528),(54.33±2.082), and(41.00±2.646), the difference was statistically significant(P < 0.05). There were the expressions of TLR2、TLR4、IL- 1 beta and TNF alpha in the normal rat cornea, and its expressions were gradually increasing after alkali burn, reaching the peak on the 7 days, then decreasing gradually, the difference of each group was statistically significant(P < 0.05). 2. The correlation:between inflammation index and inflammatory cells numbers was positive correlation(r = 0.907, P < 0.05). The correlation of inflammation index and the expressions of IL- 1 beta(r = 0.401, P = 0.197), TNF alpha(r = 0.490, P = 0.106) was not significant. The correlation of the numbers of inflammatory cells and the expression of IL- 1 beta(r = 0.439, P = 0.153), TNF alpha(r = 0.577, P = 0.050) was not significant. The correlation of the expressions of TLR2 and inflammation index level(r = 0.390, P = 0.210), the numbers of inflammatory cells(r=0.454,P=0.138)was not significant(r = 0.390, P = 0.210). The correlation of the expression of TLR4 and inflammation index level(r = 0.394, P = 0.206), the numbers of inflammatory cells(r=0.472,P=0.122)was not significant. The expression of TLR2 and IL-1 beta(r = 0.986, P < 0.05), TNF alpha(r = 0.986, P < 0.05) were positive correlation. The expression of TLR4 and IL-1 beta(r = 0.975, P < 0.05), TNF alpha(r = 0.990, P < 0.05) were positive correlation.Conclusion: TLRs participated and may start immune and inflammatory response after corneal alkali burn, mediated the production of inflammatory cytokine.