白细胞介素8在溃疡性结肠炎患者肠黏膜中的表达

Expression of Interleukin-8 in Colonic Mucosa of Patients with Ulcerative Colitis

目的探讨白细胞介素8(IL-8)在溃疡性结肠炎(UC)发病机制中的作用。方法 48例UC肠黏膜标本取自行结肠镜检查的患者,按病理组织学对炎症进行分级,Ⅲ、Ⅳ级30例,I、Ⅱ级18例;对照组为30名健康成人。应用半定量RT-PCR检测对照组和UC组肠黏膜IL-8 mRNA表达水平,免疫组织化学方法检测IL-8蛋白的表达。结果与对照组相比,UC肠黏膜IL-8 mRNA和其蛋白过度表达(P<0.05),IL-8 mRNA表达与疾病严重程度成正相关。IL-8蛋白表达位于UC肠黏膜固有层单核细胞,病理分级Ⅲ、Ⅳ级肠黏膜IL-8蛋白表达较病理分级I、Ⅱ级组明显增加(P<0.01)。结论 UC黏膜组织中IL-8表达水平明显上调,其表达水平与病情轻重和炎症严重程度呈正相关。

Objective To explore the expression of IL-8 in colonic mucosa of patients with ulcerative colitis（UC） and the effect of IL-8 in the pathogenesis of UC.Methods Biopsy specimens of colonic mucosa were obtained from 48 patients with UC who underwent colonoscopy.The patients were classified histologically as inflammation grades Ⅲ,Ⅳ（n=30） and inflammation gradesⅠ,Ⅱ（n=18）.30 healthy adults were served as control group.Semi-quantitative reverse transcription polymerase chain reaction（RT-PCR） was used to determine the expression of IL-8 mRNA,and immunohistochemistry technique was employed to detect the expression of IL-8.Results Both IL-8 mRNA expression and IL-8 protein level were significantly enhanced in colonic mucosa of patients with UC as compared with those of healthy controls（P〈0.05）.The level of IL-8 mRNA expression was positively correlated with the severity of UC.Immunohistochemistry results showed moderate and strong IL-8 immuno-reactivity which was localized in lamina propria mononuclear cells in UC.The patients with inflammation grades Ⅲ,Ⅳ exhibited significantly higher expression of IL-8 than those with inflammation grades I,Ⅱ（P〈0.01）.Conclusions IL-8 is over-expressed in colonic mucosa of patients with UC,and the intensity of IL-8 expression is positively correlated with the degrees of inflammation and the severity of disease.