目的 探讨多房棘球蚴不同感染时间小鼠肝组织细胞外基质蛋白1（extracellular matrix protein 1,ECM1）的表达水平以及与肝纤维化过程的相关性。 方法 将40只雌性 C57BL/6小鼠随机分为多房棘球蚴感染组和对照组（20只/组）,感染组经肝门静脉接种2 000个原头节/鼠,对照组注射等量生理盐水。分别于感染后第1、6、12和24周,两组各取5只小鼠采集肝组织,切片后HE染色观察多房棘球蚴感染后小鼠肝组织病理学变化;天狼星红染色以及α-SMA染色检测小鼠肝纤维化程度;免疫组织化学染色检测肝组织中ECM1的表达水平与分布。采用Pearson相关系数法分析ECM1表达水平与肝纤维化水平的相关性。结果 HE染色结果显示,多房棘球蚴感染后6周,小鼠肝组织内可见具有明显生发层结构的病灶形成,周围炎性细胞浸润明显且伴有纤维组织增生。天狼星红染色结果显示,感染组小鼠肝组织内病灶周围胶原沉积面积占比在感染后1、6、12和24周分别为（6.97 ± 0.07）%、（10.39 ± 0.02）%、（17.31 ± 1.78）%和（22.24 ± 1.07）%,均高于对照组（ P < 0.05）;α-SMA染色结果显示,感染组肝组织病灶周围α-SMA阳性染色面积占比在感染后1、6、12和24周分别为（5.31 ± 0.39）%、（9.97 ± 1.3）%、（16.16 ± 0.17）%和（19.01 ± 0.49）%,均高于对照组（ P < 0.05）;且随着多房棘球蚴感染小鼠时间的延长病灶周围肝纤维化程度不断加重。免疫组化检测结果显示,ECM1主要表达在病灶周围的炎性细胞带中,少量表达在肝窦;感染组ECM1阳性染色面积占比在感染后1、6、12和24周分别为（8.60 ± 0.44）%、（13.90 ± 0.57）%、（16.37 ± 0.77）%和（19.50 ± 0.50）%,均高于对照组（ P < 0.05）。Pearson相关性分析显示,ECM1表达水平与天狼星红阳性染色区域面积（ r = 0.900,P < 0.01）及α-SMA阳性染色区域面积占比（ r = 0.941,P < 0.01）均呈正相关。 结论 ECM1在多房棘球蚴不同感染时间小鼠肝组织的表达均较对照组升高,并与肝纤维化程度呈正相关。

Objective To investigate the role of extracellular matrix protein 1 (ECM1) in the liver fibrosis of mice infected with Echinococcus multilocularis (Em) by detecting the expression of ECM1 and the relationship with the liver fibrosis process. Methods Forty female C57BL/6 mice were randomly divided into the Em infection group (n = 20) and the control group (n = 20). For the Em infection group, 2 000 Em protoscoleces were collected under aseptic condition and inoculated through hepatic portal vein to establish the Em infection mouse model. Mice in the control group were injected with the same volume of saline in the same way. Liver tissues were collected at 1, 6, 12 and 24 weeks after Em infection. Histopathological changes were observed through hematoxylin eosin (HE) staining. The degree of liver fibrosis was evaluated through Sirius red staining and α-SMA staining. Immunohistochemical assay was performed to detect ECM1 expression in the mouse liver. The correlation between ECM1 expression and the degree of liver fibrosis was analyzed by Pearson post analysis. Results HE staining showed that lesions with obvious germinal layer structure were formed at 6 weeks after Em infection, showing obvious infiltration of inflammatory cells in surrounding tissues, accompanied by proliferation of fibrous tissue. Sirius red staining showed that the percentages of collagen deposition area in the mice liver tissue around the metacestodes lesion at week 1, 6 weeks, 12, and 24 after infection were (6.97 ± 0.07)%, (10.39 ± 0.02)%, (17.31 ± 1.78)%, and (22.24 ± 1.07)%, respectively, which were significantly higher than those in the control group ( P < 0.05). The α-SMA staining showed that the percentages of α-SMA-positive area around the lesion in the Em infection group were (5.31 ± 0.39)%, (9.97 ± 1.3)%, (16.16 ± 0.17)%, and (19.01 ± 0.49)%, respectively, at week 1, 6, 12, and 24 after infection, which were also significantly higher than that in the control group ( P < 0.05). These results indicated that the degree of liver fibrosis around the lesion gradually increased with the duration of Em infection. Immunohistochemical staining of ECM1 showed that ECM1 was mainly expressed in the inflammatory cell band around the lesion The percentages of ECM1-positive area in the Em infection group were (8.60 ± 0.44)%, (13.90 ± 0.57)%, (16.37 ± 0.77)%, and (19.50 ± 0.50)%, respectively, at week 1, 6, 12, and 24 after infection, which were significantly higher than those in the control group ( P < 0.05). Pearson correlation analysis showed that the expression level of ECM1 was positively correlated with the positive area with Sirius red staining ( r = 0.900, P < 0.01) and the percentage of α-SMA-positive area ( r = 0.941,P < 0.01). Conclusion ECM1 expression in the Em infected mouse liver at different time points post-infection was significantly higher than that in control group, and was positively correlated with the degree of liver fibrosis.