不同年龄段大鼠骨髓基质干细胞生物学特性的比较

背景：骨髓基质干细胞取材方便，增殖力强，具有多向分化潜能，且可自体移植，是组织工程中理想的种子细胞。年龄等因素对骨髓基质干细胞生物学特性的影响鲜见报道。 目的：比较不同年龄段大鼠骨髓基质干细胞生物学特性的差异，为临床细胞移植提供实验依据。 方法：骨髓基质干细胞供体为SD大鼠。按细胞来源分为3组，即幼年组、成年组和老年组。无菌条件下剪断大鼠股骨两端，用含体积分数为10%胎牛血清的DMEM培养液冲洗骨髓腔，收集骨髓冲洗液，吹打制成单细胞悬液，通过200目的筛网滤过后将其置于培养瓶中培养。取第2代生长均一的细胞，CD44，CD29，CD90 免疫荧光鉴定；观察细胞形态及黏附速度；细胞计数，绘制生长曲线；MTT法检测3组细胞的增殖活力。 结果与结论：CD44，CD29，CD90免疫染色细胞呈阳性；幼年组骨髓基质干细胞的黏附速度快于成年组和老年组；细胞增殖幅度明显 (P < 0.05)；MTT法测定结果显示幼年组骨髓基质干细胞活力强，与另外两组比较差异具有显著性意义(P < 0.05)。提示幼年SD大鼠骨髓基质干细胞增殖快、活力强、可在短时间内大量扩增，是理想的组织工程细胞。

Comparison of biological characteristics of rat bone marrow stromal stem cells at different ages

BACKGROUND: Bone marrow stromal stem cells (BMSCs) have multiple differentiation abilities. BMSCs are easily obtaining, have strong proliferative ability and can do autologous transplantation. Therefore, it is an ideal seed cells in tissue engineering. Few studies have addressed effects of age on biological characteristics of BMSCs. OBJECTIVE: To compare differences in biological characteristics of BMSCs from rats at different ages, and to provide experimental evidence for clinical cell transplantation. METHODS: BMSCs were obtained from Sprague-Dawley rats. SD rats were divided into three groups according to the source of cells, namely childhood group, adult group, gerontism group. The femur at both ends was cut under sterile conditions. Bone marrow cavity was washed using DMEM medium containing 10% fetal bovine serum. Bone marrow fluid was collected. Single cell suspension was made, and placed in culture flask after filtration through 200 meshes. The second passage of cells was obtained. CD44, CD29, CD90 protein expression was determined using immunofluorescence staining. Morphology and adhesion rate of BMSCs were observed. The cell growth curve was drawn by cells counting. Activity of BMSCs was detected using MTT assay. RESULTS AND CONCLUSION: The cells were positive for the CD44, CD29 and CD90 immunostaining. The adhesion rate of childhood group was faster than adult and gerontism groups as well as the proliferation rate (P < 0.05). MTT assay showed that the viability of childhood group was significantly stronger than the other two groups (P < 0.05). Results indicated that BMSCs from the young rats are the ideal tissue engineering cells, for the characters of dynamic and fast amplification in a short time.