小鼠胎盘间充质干细胞移植对造血系统自然衰老的影响

Effects of mouse placenta-derived mesenchymal stem cells on the natural senescence of the mouse hematopoietic system

背景:造血系统作为人体重要组成部分,随着年龄的增长会出现功能不断衰退。目的:观察小鼠胎盘间充质干细胞对小鼠造血系统自然衰老的延缓作用。方法:取孕13.5dBalb/c小鼠胎盘,制备胎盘间充质干细胞。6月龄Balb/c小鼠48只随机分均为细胞移植组和对照组。细胞移植组尾静脉输注胎盘间充质干细胞,每月1次,共6次;对照组输注生理盐水。第3个月进行外周血象、骨髓有核细胞计数、成纤维细胞集落培养、造血祖细胞集落培养和外源性脾集落形成单位计数检测;第6个月时增加骨髓切片观察、骨髓细胞重建造血能力测定。结果与结论:细胞移植组小鼠一般情况优于对照组;干预第3个月,细胞移植组的骨髓有核细胞计数、巨噬系祖细胞、巨核系祖细胞多于对照组,其他指标无明显差别;干预第6个月,除外周血象仍无差别外,其他的上述指标均明显高于对照组;观察期内两组的上述指标均随时间延长呈下降趋势,但细胞移植组下降速度明显慢于对照组,差异有显著性意义(P<0.05)。组织学观察发现,细胞移植组骨髓造血组织较对照组丰富,而对照组骨髓脂肪化显著增加;实验还发现细胞移植组骨髓细胞的造血重建能力明显优于对照组。结果提示,小鼠胎盘间充质干细胞能够延缓小鼠造血系统的衰退。

BACKGROUND： Hematopoietic system,as an important part of human body,will appear continuously functional recession with age.OBJECTIVE： To explore the anti-aging role of mouse placenta-derived mesenchymal stem cells （mPMSCs） on the natural senescence of the mouse hematopoietic system.METHODS： Experimental method： ①Preparation of the mPMSC： the placentas were collected from 6 pregnant 13.5 d Balb/c mice,and digested by 0.1% collagenase IV to obtain the cells,and the cells were plated,passaged,and identified as mPMSCs.②Intervention of the mPMSCs： 6 month old Balb/c mice （48） were randomly divided into experimental and control groups.Mice of experimental group were injected with mPMSC （5×106 for each one） through tail intravenation,once a month,a total of six times;and mice of control group with physiological saline.Experimental assessment： ①The mPMSCs preparation： the morphology of cells was observed through inverted phase microscope,cell-surface markers by flow cytometry,cell differentiation potentials by inducing osteoblast differentiation and adipocyte differentiation.②The mPMSCs intervention： on the third month after treatment,peripheral blood （WBC,Hb）,bone marrow mononuclear cell count （BMNC）,fibroblasts colony culture （CEU-F）,hematopoiesis progenitor cell colony culture （CFU-GM,CFU-E,CFU-MK） and exogenous spleen colony-forming units count （CFU-S） were compared between two groups;on the basis of above indexes,the bone marrow histology and the capability of hematopoietic reconstruction of bone marrow cells were added on the sixth month after treatment.RESULTS AND CONCLUSION： The general status of mice in the experimental group was better than that in the control group;in the third month,BMNC,CFU-GM and CFU-MK of the experimental group were higher than that of the control group,but no significant difference on the peripheral blood,CFU-F and CFU-E;on the sixth month,all the indexes mentioned above were higher than control group with exception of peripheral blood;during observation period all the indexes had a similar descending-tendency ,but the tendency of experimental group was much slower than that of control group with significant difference （P 0.05）.Furthermore,the experimental group had more hematopoietic tissue but less adipose tissue than that of control group;The capacity of hematopoietic reconstruction of bone marrow cells from experimental group was better than that of control group.The results indicated that mPMSCs could delay the natural recession of mouse hematopoietic system.