Kierney P C, Dorshkind K
Division of Biomedical Sciences, University of California, Riverside 92521-0121.
Blood. 1987 Nov;70(5):1418-24.
The aim of this study was to investigate the relative contribution of direct contact with stromal cells v stromal cell-derived soluble mediators to the differentiation of B lymphocytes and cells from other hematopoietic lineages. This was investigated by making a comparison between hemopoietic cells grown in direct contact with stroma to those in diffusion chambers (DCs) placed over purified populations of stroma. The source of stromal cells was adherent layers from myeloid or lymphoid long-term bone marrow cultures that had been treated with mycophenolic acid, an antibiotic that depletes hemopoietic cells from the cultures but retains a functional stroma. The cells seeded into the chambers were fresh marrow cells that had been passed through two consecutive nylon wool columns to deplete cell populations capable of forming an adherent cell layer in vitro. DCs were placed in wells in which the adherent stroma, growing under myeloid or lymphoid conditions, was present. The results indicate that progenitors of granulocytes and macrophages survived and differentiated in DCs under myeloid culture conditions, as the number of cells and absolute number of CFU-GM increased over that present in the reseed population. These levels, however, were markedly less than in parallel cultures in which the cells were seeded directly onto stroma. Hematopoiesis in DCs placed over hemopoietically active stroma was not optimal, suggesting that factors were used by those hemopoietic cells closest to the stroma. A B lymphocyte precursor survived in DCs under myeloid but not lymphoid conditions, and its differentiation into B lymphocytes was dependent on close association with stromal cells; B lymphopoiesis initiated when cells from DCs grown under myeloid conditions were harvested from the chambers and seeded directly onto stroma initiated and maintained under lymphoid bone marrow culture conditions. B lymphopoiesis did not initiate if the DC from the myeloid conditions was left intact and placed directly over a lymphoid stromal cell layer in lymphoid conditions.
本研究的目的是调查与基质细胞直接接触相对于基质细胞衍生的可溶性介质对B淋巴细胞和其他造血谱系细胞分化的相对贡献。通过比较与基质直接接触生长的造血细胞与置于纯化基质群体上的扩散室（DC）中的造血细胞来进行研究。基质细胞的来源是来自经霉酚酸处理的髓系或淋巴系长期骨髓培养物的贴壁层，霉酚酸是一种抗生素，可从培养物中耗尽造血细胞，但保留功能性基质。接种到室中的细胞是新鲜骨髓细胞，这些细胞已连续通过两个尼龙毛柱以耗尽能够在体外形成贴壁细胞层的细胞群体。DC被放置在存在于髓系或淋巴系条件下生长的贴壁基质的孔中。结果表明，在髓系培养条件下，粒细胞和巨噬细胞的祖细胞在DC中存活并分化，因为细胞数量和CFU-GM的绝对数量比再接种群体中的增加。然而，这些水平明显低于细胞直接接种到基质上的平行培养物中的水平。置于造血活性基质上的DC中的造血不是最佳的，这表明最接近基质的那些造血细胞利用了一些因子。B淋巴细胞前体在髓系而非淋巴系条件下的DC中存活，其分化为B淋巴细胞依赖于与基质细胞的紧密关联；当从在髓系条件下生长的DC中收获细胞并直接接种到在淋巴系骨髓培养条件下启动和维持的基质上时，B淋巴细胞生成开始。如果髓系条件下的DC保持完整并直接置于淋巴系条件下的淋巴基质细胞层上，则B淋巴细胞生成不会启动。
