骨髓间充质干细胞经心外膜移植到心肌梗死大鼠体内后在肝脾的分布及对肝脾功能影响的实验研究

目的心肌梗死后经心外膜注射骨髓间充质干细胞(bone marrow mesenchymal stem cells,MSCs)后移植细胞在心外脏器(肝脾)的分布及对肝脾功能的影响。方法体外培养扩增雄性Lewis大鼠的MSCs,并用5-溴脱氧尿苷(Bromodeoxyuridine,Brdu)标记,建立心肌梗死后3周的雌性大鼠模型,将MSCs(3×106,50μL)经心外膜注射到大鼠模型(n=22)的心肌梗死边缘区,对照组(n=21)注射同等量磷酸盐缓冲液(Phosphate Buffered Saline,PBS)。4周后,检查大鼠心功能改变情况,并分别取肝脾和外周血液,行免疫组化,HE染色,肝功能检测,血常规,IgM检测等。结果 MSCs移植后4周,MSCs移植组心功能较对照组改善,免疫双染示MSCs向肝样细胞分化,HE染色示肝脾淤血减轻,丙氨酸氨基转移酶(ALT)、直接胆红素(DBIL)显著低于对照组,白蛋白(ALB)高于对照组,脾指数低于对照组。结论经心外膜注射MSCs可以改善心脏功能,移植后少量细胞滞留于肝脾,但对肝脾的功能均无明显影响。

Distribution and Impact of Bone Marrow Mesenchymal Stem Cells in Liver and Spleen after Intramyocardial Injection in a Rat Chronic Myocardial Infarction Model

Objective To study the distribution and impact of bone marrow mesenchymal stem cells（MSCs） in liver and spleen after intramyocardial injection in a rat chronic myocardial infarction model. Methods MSCs were isolated from bone marrow aspirates of male Lewis rats and expanded ex vivo.MSCs were labeled with Bromodeoxyuridine （BrdU）. Three weeks after coronary ligation,female Lewis rats were randomized into 2 groups.Labeled MSCs （3×106,50μL） were injected into the border zone of infarcted area in group 1（n=22）. Phosphate Buffered Saline（PBS） of equal volume were injected into the border zone of infarcted area in group 2（n=21）.Four weeks after MSCs injection, the liver and spleen were harvested for immunohistochemistry examination, hematoxylin-eosin （HE）staining. The distribution of MSCs in liver and spleen was evaluated through Real-time PCR .The blood samples were obtained to analyze the concentration of markers of liver and spleen function. Liver index and Spleen index were also evaluated. Results We found the heart function of group 1 was significant improved than group 2. MSCs which injected into border zone of infarcted area immigrated to liver and spleen.The engrafted cells localized in livers were exhibited an hepatocyte/fi broblast-like morphology in group 1.The serum activities of alanine transarninase （ALT）,direct bilirubin（DBIL）,and spleen weight/body weight ratio of group 1 were significantly lower than group 2（P〈0.05）.Albumin（ALB） in group 1 was significantly higher than group 2（P〈0.05）. Conclusion After intramyocardial injection, MSCs migrated to the extra-cardiac organs including liver and spleen. There was no evidence that those immigrated cells had negative impact on liver and spleen function.