胆道闭锁肝纤维化病变中平滑肌肌动蛋白表达的研究

目的 本研究通过检测平滑肌肌动蛋白(α-SMA)在胆道闭锁(BA)肝组织和肝外胆系的表达,探讨肝纤维化过程与临床预后的关系.方法 采用免疫组化染色方法对2005年7月至2006年5月本院21例BA肝组织、肝门纤维块进行CD68和α-SMA染色;对照组为5例胆汁淤积和10例胆总管囊肿.选用LEICA-DM研究级生物显微镜,QWIN软件环境下测量抗体阳性细胞面积百分比和平均光密度,随访19例BA术后3个月直接胆红素下降比率.同时对21例BA肝组织纤维化分级,并与α-SMA表达量进行相关分析.结果 α-SMA在BA肝纤维块高度表达于胆管上皮、胆管周围的胶原纤维;α-SMA阳性表达量和表达强度明显高于对照组,其表达量与表达强度呈线性正相关(r=0.549,P=0.022);CD68在BA肝组织表达较对照组明显增强,但肝门纤维块鲜有表达.α-SMA表达量与肝脏纤维化分级呈正相关(P=0.02);α-SMA阳性表达面积百分比与术后3个月直接胆红素下降率呈负相关(r=-0.653,P=0.029),但肝组织CD68表达与α-SMA阳性表达相关性不明显(r=0.444,P=0.057).结论 α-SMA的表达可能是肝脏纤维化的早期标志,SMA的阳性表达量与术后3个月胆红素消退呈显著负相关,预示BA肝内外胆管系统纤维化,乃至肝硬化,提示可能临床预后不佳.

A study of α-SMA expresson in the fibrous cone in biliary atresia

Objective The aim of this study was to evaluate the α-SMA expression in liver andporta hepatis in biliary atresia patients.Methods From Sept 2005 to May 2006,21 patients with bili-ary atresia underwent Kasai procedure.Liver biopsy and the fibrous cone of porta hepatis were stud-ied.5 cases of cholestasis syndrome and 10 cases of choledochal cyst were used as the control group.Immunohistoehemistry of α-SMA and CD68 in BA's liver and porta hepatic was performed.Leica DM microscope was used to acquire the image of immunohistochemistry.Qwin software was used for mor-phometric study.Semi-quantitative 3 grade staging system was employed to estimate the liver fibrosis.The densities of CD68 in BA's liver and the level of direct bilirubin were assessed in relation tO the α-SMA expression.SPSS software was used for statistical analysis.Results (1)α-SMA was highly ex-pressed in the epithelial cells and periductular collagen fiber.The expression in BA was stronger than that of the control group(r=0.549,P=0.022).(2)The amount of α-SMA in BA positively correla-ted with the liver fibrosis score(P=0.02).(3)The proportions of α-SMA in liver of BA negatively related with the reduction rate of direct bilirubin 3 months postoperatively.(r=-0.653,P=0.029).(4)The correlation between the α-SMA and CD-68 expression was not significantly(r=0.444,P=0.057).Conclusions In this study,expression of α-SMA in liver of BA patient iS higher than that of the control group.This indicates that the liver fibrogenesis started early in BA.α-SMA expressing negatively correlated with the reduction of direct bilirubin 3 months postoperatively,suggesting fibro-sis,or cirrhosis,in the entire biliary system.