a Blood Transfusion Research Center, High Institute for Education and Research in Transfusion Medicine , Tehran , The Islamic Republic of Iran.
Artif Cells Nanomed Biotechnol. 2016 Nov;44(7):1702-7. doi: 10.3109/21691401.2015.1089251. Epub 2015 Oct 15.
Platelet micro-particles (MPs) contain CXCR4 markers and are able to transfer them into hematopoietic stem cells. Therefore, effect of platelet MPs (PMPs) on the expression levels of CXCR4 and CD34 markers in these cells was examined. Isolated CD 133+ cells cultivated for 5 d in the stem span medium and PMPs. Fold increase of CD34+ cells in the presence of 5 and 10 g/ml of PMPs was increased significantly. CXCR4+ cell percent in the presence of 10 g/ml PMPs compared with control cells (63.8 ± 6.4) was increased (P < 0.05). PMPs were no affect on clonogenicity of hematopoietic progenitor cells.
Cord blood CD133+ cells are able to maintain long-term hematopoiesis and to differentiate to hematopoietic lineages. CXCR4 over expression is involved in homing and successful transplantation of hematopoietic stem cells (HSCs) in the bone marrow. PMPs contain CXCR4 markers and are able to transfer them into hematopoietic stem cells. Therefore, considering the importance of CD133+ cells as primitive HSCs, the effect of PMPs on the expression levels of CXCR4 and CD34 markers in these cells was examined.
Cord blood CD133+ cells were isolated by MACS. Isolated cells were divided into three groups: (i) control cells, (ii) cells treated with 5 μg/ml PMPs, (iii) cells treated with 10 μg/ml PMPs. Cells were cultivated for 5 d in the stem span medium. Expression of CD 133, CD34, and CXCR4 surface marker was analyzed by flow cytometry. Total cell numbers were counted by hemocytometer and clonogenicity were measured by colony assay.
PMPs were no effect on CD133+ cells proliferation, but fold increase of CD34+ cells in the presence of 5 and 10 g/ml of PMPs was increased significantly. CXCR4+ cell percent in the presence of 10 g/ml PMPs compared with control cells (63.8 ± 6.4) was increased (P < 0.05). PMPs were no affect on clonogenicity of hematopoietic progenitor cells.
Exposure of CD133+ cells isolated from cord blood to PMPs with 10 μg/ml concentration increased the expression of CXCR4 surface marker significantly.
血小板微颗粒（PMPs）含有 CXCR4 标志物，并能够将其转移到造血干细胞中。因此，研究了 PMPs 对这些细胞中 CXCR4 和 CD34 标志物表达水平的影响。
从脐带血中分离出 CD133+细胞。将分离出的细胞分为三组：（i）对照组，（ii）用 5μg/ml PMPs 处理的细胞，（iii）用 10μg/ml PMPs 处理的细胞。将细胞在 StemSpan 培养基中培养 5 天。通过流式细胞术分析 CD133、CD34 和 CXCR4 表面标志物的表达。用血细胞计数器计数总细胞数，并通过集落形成测定法测量集落形成能力。
PMPs 对 CD133+细胞的增殖没有影响，但在 5 和 10μg/ml PMPs 的存在下，CD34+细胞的倍数增加明显。与对照组（63.8±6.4）相比，10μg/ml PMPs 存在时的 CXCR4+细胞百分比增加（P<0.05）。PMPs 对造血祖细胞的集落形成能力没有影响。
暴露于 10μg/ml 浓度的 PMPs 会使从脐带血中分离出的 CD133+细胞的 CXCR4 表面标志物表达显著增加。
