利用人脐血单个核细胞重建急性肝损伤小鼠肝组织的实验研究

Human Umbilical Cord Blood-derived Mononuclear Cells Repopulate Injured Mouse Liver

摘要:

利用人脐血单个核细胞重建急性肝损伤小鼠肝组织，探索建立人-小鼠嵌合肝模型方法。15只SCID小鼠，以四氯化碳（CCL4）制备急性肝损伤模型，24h后行2/3肝切除，然后分为三个实验组：细胞移植组（7只）、阴性对照组（3只）及空白对照组（5只）；将人脐血单个核细胞悬液注入细胞移植组小鼠脾脏内，阴性对照组小鼠脾脏内注入等量磷酸盐缓冲液(PBS)，空白对照组不注射细胞悬液和PBS。术后7d、14d及21d取小鼠肝组织观察病理变化、检测人白蛋白（ALB）及细胞角蛋白19（CK19），同时检测小鼠血清及肝组织匀浆中人ALB含量。 全部小鼠表现出急性肝损伤组织学特征；细胞移植组小鼠术后7ｄ、14ｄ、21d肝组织内均见大量人ALB及CK19阳性表达细胞，血清及肝组织匀浆可检测出人ALB；阴性对照组小鼠肝组织未见人ALB及CK19阳性表达，血清及肝组织匀浆中未检测出人ALB。 人脐血单个核细胞在部分肝切除的急性肝损伤小鼠肝组织内可大量分化为人肝细胞及胆管细胞，在建立模型方面已取得关键突破。

Abstract:

AIM To repopulate the liver of mice with acute liver injury and to make mouse models with chimeric liver by using human umbilical cord blood (hUCB)-derived mononuclear cells. METHODS Fifteen acute liver injury mouse models were induced by carbon tetrachloride intraperitoneal injection followed by two-thirds hepatectomy and all mice were divided into three groups: cell transplantation group (n=7), negative control group (n=3) and blank control group(n=5). HUCB cell preparations were transplanted into mouse spleens of cell transplantation group and phosphate bufferd saline (PBS) was injected into spleens of negative controls. Neither cell suspension nor PBS was given to the blank controls. Pathological changes were observed 7, 14 and 21 days after cell transplantation. Human albumin (ALB) and cytokeratin 19 (CK19) were also detected in the mouse sera and liver tissues. RESULTS All mice showed histological features of acute liver injury. Positive expression of human ALB and CK19 were observed in liver tissues of cell transplantation group 7, 14 and 21 days after cell transplantation. Human ALB could be detected from the sera and liver homogenates of cell-transplanted mice. No positive expression of human ALB and CK19 were observed in liver tissues and no human ALB was detected in sera of negative control group. CONCLUSIONS HUCB-derived mononuclear cells can differentiate into functional human hepatocytes and biliary cells in large quantity in mouse models with acute liver injury, thus a great progress were made in establishing mouse models with chimeric liver.