Unidad de Terapia Celular-Laboratorio de Patología Celular y Molecular, Centro de Medicina Experimental, Instituto Venezolano de Investigaciones Científicas (IVIC), Caracas, Venezuela.
Stem Cells Dev. 2012 Nov 20;21(17):3187-96. doi: 10.1089/scd.2012.0084. Epub 2012 May 18.
Multipotent mesenchymal stromal cells (MSCs) from the human olfactory mucosa (OM) are cells that have been proposed as a niche for neural progenitors. OM-MSCs share phenotypic and functional properties with bone marrow (BM) MSCs, which constitute fundamental components of the hematopoietic niche. In this work, we investigated whether human OM-MSCs may promote the survival, proliferation, and differentiation of human hematopoietic stem cells (HSCs). For this purpose, human bone marrow cells (BMCs) were co-cultured with OM-MSCs in the absence of exogenous cytokines. At different intervals, nonadherent cells (NACs) were harvested from BMC/OM-MSC co-cultures, and examined for the expression of blood cell markers by flow cytometry. OM-MSCs supported the survival (cell viability >90%) and proliferation of BMCs, after 54 days of co-culture. At 20 days of co-culture, flow cytometric and microscopic analyses showed a high percentage (73%) of cells expressing the pan-leukocyte marker CD45, and the presence of cells of myeloid origin, including polymorphonuclear leukocytes, monocytes, basophils, eosinophils, erythroid cells, and megakaryocytes. Likewise, T (CD3), B (CD19), and NK (CD56/CD16) cells were detected in the NAC fraction. Colony-forming unit-granulocyte/macrophage (CFU-GM) progenitors and CD34(+) cells were found, at 43 days of co-culture. Reverse transcriptase-polymerase chain reaction (RT-PCR) studies showed that OM-MSCs constitutively express early and late-acting hematopoietic cytokines (i.e., stem cell factor [SCF] and granulocyte- macrophage colony-stimulating factor [GM-CSF]). These results constitute the first evidence that OM-MSCs may provide an in vitro microenvironment for HSCs. The capacity of OM-MSCs to support the survival and differentiation of HSCs may be related with the capacity of OM-MSCs to produce hematopoietic cytokines.
人嗅黏膜（OM）中的多能间充质基质细胞（MSCs）被认为是神经祖细胞的龛位细胞。OM-MSCs 具有与骨髓（BM）MSCs 相似的表型和功能特性，而 BM-MSCs 是造血龛的基本组成部分。在这项工作中，我们研究了人 OM-MSCs 是否可以促进人造血干细胞（HSCs）的存活、增殖和分化。为此，将人骨髓细胞（BMCs）与 OM-MSCs 共培养，而不添加外源性细胞因子。在不同的时间间隔内，从 BMC/OM-MSC 共培养物中收获非贴壁细胞（NAC），并通过流式细胞术检查血细胞标志物的表达。在共培养 54 天后，OM-MSCs 支持 BMC 的存活（细胞活力>90%）和增殖。在共培养 20 天时，流式细胞术和显微镜分析显示，表达泛白细胞标志物 CD45 的细胞比例很高（73%），并且存在髓系起源的细胞，包括多形核白细胞、单核细胞、嗜碱性粒细胞、嗜酸性粒细胞、红细胞和巨核细胞。同样，在 NAC 部分也检测到 T（CD3）、B（CD19）和 NK（CD56/CD16）细胞。在共培养 43 天时，发现集落形成单位-粒细胞/巨噬细胞（CFU-GM）祖细胞和 CD34+细胞。逆转录-聚合酶链反应（RT-PCR）研究表明，OM-MSCs 持续表达早期和晚期造血细胞因子（即干细胞因子 [SCF] 和粒细胞-巨噬细胞集落刺激因子 [GM-CSF]）。这些结果首次证明 OM-MSCs 可为 HSCs 提供体外微环境。OM-MSCs 支持 HSCs 存活和分化的能力可能与其产生造血细胞因子的能力有关。
