TGF-β_1中和抗体对TNBS慢性结肠炎动物模型纤维化的影响

Effect of TGF-β_1 neutralizing antibody on intestinal fibrosis in a mouse model of chronic colitis induced with trinitrobenzene sulfonic acid

目的观察转化生长因子-(transforming growth factor β_1,T G F-β_1)中和抗体对2,4,6-三硝基苯磺酸(trinitrobenzene sulfonic acid,TNBS)慢性结肠炎动物模型中小鼠肠道纤维化的影响.方法将48只Balb/c小鼠分为正常对照组、TNBS模型组、治疗对照组和TGF-β_1抗体组,TNBS 6 wk灌肠造模,TGF-β_1抗体组于每次TNBS灌肠后24 h给予TGF-β_1抗体灌肠治疗,光镜下观察结肠组织学变化,RT-PCR检测各组小鼠肠道中Ⅰ、Ⅲ、Ⅴ型胶原蛋白及TGF-bmRNA水平,免疫组织化学、Western blot检测各组小鼠结肠中TGF-β_1水平并分析结果 .结果 (1)HE染色和VG胶原蛋白染色发现,TGF-β_1抗体组小鼠未见大量胶原蛋白聚集,固有肌层明显增厚,较TNBS模型组、治疗对照组改善;(2)TGF-β_1抗体组结肠Ⅰ、Ⅲ、Ⅴ型胶原蛋白及TGF-bmRNA较TNBS模型组及治疗对照组均降低(P<0.05);(3)免疫组织化学、Western blot发现TGF-β_1抗体组较TNBS模型组及治疗对照组结肠内TGF-β_1均降低(P<0.05).结论 TGF-β_1中和抗体拮抗TGF-β_1,下调小鼠结肠组织中胶原蛋白的表达,抑制TNBS慢性结肠炎动物模型纤维化.

AIM To evaluate the effect of transforming growth factor-β1（TGF-β1） neutralizing antibody on intestinal fibrosis in a mouse model of chronic colitisinduced with trinitrobenzene sulfonic acid（TNBS）.METHODS Forty-eight Balb/c mice were randomly divided into a normal control group,a model control group,a treatment control group,and a TGF-β1 antibody group.Chronic colitis and intestinal fibrosis were induced with TNBS/ethanol enema for 6 wk.Mice in the TGF-β1antibody group and treatment control group were administered with TGF-β1 neutralizing antibody and physiological saline,respectively,at 24 h after the administration of TNBS/ethanol enema.The pathological changes in intestine tissue were detected by HE and VG collage staining.Expression of TGF-β1 and collagen types Ⅰ,Ⅲ,and Ⅴ mRNAs in the colon was detected.RESULTS HE and VG collage staining showed that pathologic histology was improved in the TGF-β1 antibody group.The expression of collagen types Ⅰ,Ⅲ,and Ⅴ and TGF-β1mRNAs decreased significantly in the TGF-β1antibody group compared with the model control group and the treatment control group（P〈0.05）.The protein expression of TGF-β1also decreased significantly in the TGF-β1antibody group compared with the model control group and the treatment control group（P〈0.05）.CONCLUSION TGF-β1 neutralizing antibody can effectively down-regulate the expression of TGF-β1 and collagen in mice with chronic colitis,and intestinal fibrosis can be abrogated by targeting TGF-β1.