骨髓增生异常综合征患者源成骨细胞表达多种细胞因子并体外维持造血祖细胞存活

为了解骨髓增生异常综合征（MDS）患者成骨细胞的生物学特性,并探讨其对体外造血的支持能力,利用骨髓间充质干细胞多向分化潜能将其诱导分化为成骨细胞,在体外和造血细胞构建二维培养体系,研究其体外支持造血祖细胞生存的作用;同时采用RT-PCR的方法在mRNA水平上分析由骨髓间充质干细胞诱导分化的成骨细胞细胞因子的表达并与人成骨细胞系hFOB1.19比较。结果发现,来源于MDS患者的成骨细胞在无外源性细胞因子的条件下能够短期维持GM-CFC造血祖细胞的存活。经过RT-PCR证实,人成骨细胞系hFOB1.19表达SCF、IL-6、SDF-1α、G-CSF、GM-CSF等细胞因子,来源于MDS患者和正常人的成骨细胞也能表达上述细胞因子,但却不表达GM-CSF。结论：与正常人相比,MDS患者源的成骨细胞同样能够维持GM-CFC的存活,这可能和成骨细胞表达多种重要的造血相关的细胞因子有关。

Osteoblasts from Patients with Myelodysplastic Syndrome Express Multiple Cytokines and Support Hematopoietic Progenitor Cell Survival In Vitro

This study was aimed to investigate the biological characteristics of osteoblasts from patients with myelodysplastic syndrome (MDS) and their supportive capacity for hematopoiesis in vitro. A two-dimensional culture system was constructed by using osteoblasts derived from human marrow mesenchymal stem cells (MSC); MSCs were isolated from bone marrow of MDS patients and normal individuals and were cultured; the third passage of MSCs were induced into osteoblasts which were treated with mitomycin C and confluenced into a feeder layer. Ficolled bone marrow mononuclear cells were obtained from normal individuals and seeded into the two-dimensional culture system to culture in vitro without exogenous cytokines. By using colony-forming assay, the ability of the two-dimensional system to culture HPCs was observed. The cytokine expression of osteoblasts from MDS patient bone marrows in mRNA level was detected by RT-PCR and was compared with human osteoblast cell line hFOB1.19. The results showed that the osteoblasts from MDS patients could support short-term survival of GM-CFC in condition without exogenous cytokines, that is, osteoblasts played a crucial role in regulation of HPC growth. The results of RT-PCR clearly demonstrated that the osteoblast cell line hFOB1.19 expressed SCF, IL-6, SDF-1alpha, G-CSF and GM-CSF. The same expression patterns of above cytokines were also seen in osteoblasts derived from BM-MSCs of MDS patients and normal individuals, but these cells did not express GM-CSF. It is concluded that the biological characteristics of osteoblasts from bone marrow of MDS patients are generally not different from those of osteoblasts from normal bone marrow. Both of them can support GM -CFC to form colonies in vitro, it may be associated with expressing important related cytokines by osteoblasts.