摘要目的 观察重组白细胞介素10(IL-10)对大肠杆菌内毒素(LPS)诱导的实验性葡萄膜炎(EIU)的治疗作用.方法 雄性Wistar大鼠56只随机分为3组,其中IL-10治疗组和阳性对照组各24只,正常对照组8只.治疗组和阳性对照组大鼠用LPS诱导EIU模型,治疗组24只大鼠在注射LPS前4.0、0.5 h分别按1μg/kg的剂量经尾静脉注射重组IL-10各1次,正常对照组大鼠同一部位注射等量生理盐水.阳性对照组和正常对照组大鼠用于对比观察.注射LPS后观察大鼠的发病开始时间和眼部表现,分别在注射LPS后4、24 h和3 d等3个时间点分批处理8只大鼠后取血和房水,检测血清和房水中肿瘤坏死因子(TNF)α、IL-6和IL-10水平,并进行病理检查和分级.结果 阳性对照组24只大鼠全部出现葡萄膜炎反应,平均发病开始时间为(3.81±1.05)h,平均炎症评分为3.67±1.97,平均组织病理学分级为3.08±1.77.治疗组24只大鼠也全部出现轻度葡萄膜炎反应,平均发病开始时间为(5.63±1.02)h,平均炎症评分为2.00±1.25,平均组织病理学分级为1.67±1.17.治疗组大鼠的发病开始时间明显迟于阳性对照组大鼠(t=4.95,P=0.00),炎症评分(t=3.50,P=0.00)和组织病理学分级(t=3.28,P=0.00)也显著低于阳性对照组.正常对照组8只大鼠始终无阳性体征及病理改变.阳性对照组大鼠血清、房水TNF-α和IL-6水平明显高于治疗组和正常对照组(F=15.34,57.65,67.59,8.42;P=0.00),治疗组大鼠血清和房水IL-10水平明显高于阳性对照组和正常对照组(F=17.84,7.76;P=0.00).房水TNF-α、房水和血清IL-6与眼部炎症程度呈正相关(眼部表现评分r=0.58,0.31,0.81;组织病理学分级r=0.56,0.31,0.74;P=0.00);血清IL-10与炎症程度呈负相关(眼部评分和组织病理学分级分别为r=-0.54,-0.55;P=0.00),与发病开始时间呈正相关(r=0.73,P=0.00);血清及房水TNF-α和IL-6水平与发病开始时间呈负相关(r=-0.47,-0.59,-0.77,-0.36;P＜0.05).结论 IL-10能显著抑制LPS诱导的EIU模型中前炎症因子TNF-α和IL-6产生,减轻EIU眼部表现和病理损害,具有治疗EIU的作用.

abstractsObjective To examine the role of recombinant interleukin-10 (IL-10) and the therapeutic effect of endotoxin-induced uveitis (EIU) in rats. Methods Fifty-six male Wistar rats were randomized into three groups. IL-10 treatment group and positive control group had 24 rats respectively, and the normal control group had eight rats. Endotoxin-induced uveitis (EIU) is an established animal model of acute ocular inflammation induced by LPS intravenous injection ( 1 μg/kg). The onset times and signs were observed and the clinical scores were recorded. The blood samples and the aqueous humor samples of right eye were collected separately before the rats were sacrificed at fourth hour, 24th hour and third day after LPS injection. The enzyme-linked immunosorbent assay was used to measure tumor necrosis factor (TNF) α,IL-6, and IL-10 levels in the serum and aqueous humor. The left eyes were used for pathological examination and pathological grading. Results The symptoms of uveitis were appeared in all 24 rats in the positive group. The average onset time was (3.81 ± 1.05) hours, the average clinical score was 3.67±l. 97. The mild manifestations of uveitis were also appeared in all of the rats in treatment group. The average onset time was (5. 63±1.02) hours, the average clinical score was 2.00± 1.25. The average onset time in treatment group was postponed compared with the rats of positive group (t=4.95, P=0. 000).The clinical scores (t= 3. 50, P= 0. 00) and the pathological grades (t= 3.28, P= 0. 00) in treatment group were lower than those of positive group. There were not signs or pathologic changes in all the eight rats in the negative control group. The serum and aqueous humor levels of TNF-α and IL-6 in the rats of positive group were higher than those of the treatment group and control group (F=15.34, 57.65, 67.59, 8.42;P=0. 00). The serum and aqueous humor levels of IL-10 in the rats of treatment group were higher than those of the positive group and the control group (F = 17.84, 7.76; P = 0.00). There were positive correlations between the level of aqueous humor TNF-α, serum and aqueous humor levels of IL-6 and the disease severity (reye=0. 58, 0. 31, 0. 81, rpath =0. 56, 0. 31, 0. 74; P＜0.05). The negative correlations were presented between the serum levels of IL-10 with the disease severity (r=- 0. 54,-0. 55; P= 0.00).There were negative correlations between the serum and aqueous humor levels of TNF-α and IL-6 and the onset timeof the disease (r=-0.47,-0.59,-0.77,-0.36; P＜0.05) as well. Conclusions These findings strongly suggest that suppressive IL-10 is a potent candidate for the prevention of TNF-α and IL-6 in uveitis and could be applied as a novel immunoregulatory agent to control EIU.