Johnson A, Dorshkind K
Blood. 1986 Dec;68(6):1348-54.
Hemopoiesis in long-term bone marrow cultures (LTBMC) is dependent on adherent stromal cells that form an in vitro hemopoietic microenvironment. Myeloid bone marrow cultures (MBMC) are optimal for myelopoiesis, while lymphoid bone marrow cultures (LBMC) only support B lymphopoiesis. The experiments reported here have made a comparative analysis of the two cultures to determine whether the stromal cells that establish in vitro are restricted to the support of myelopoiesis or lymphopoiesis, respectively, and to examine how the different culture conditions affect stromal cell physiology. In order to facilitate this analysis, purified populations of MBMC and LBMC stroma were prepared by treating the LTBMC with the antibiotic mycophenolic acid; this results in the elimination of hemopoietic cells while retaining purified populations of functional stroma. Stromal cell cultures prepared and maintained under MBMC conditions secreted myeloid growth factors that stimulated the growth of granulocyte-macrophage colonies, while no such activity was detected from purified LBMC stromal cultures. However, this was not due to the inability of LBMC stroma to mediate this function. Transfer of LBMC stromal cultures to MBMC conditions resulted in an induction of myeloid growth factor secretion. When seeded under these conditions with stromal cell-depleted populations of hemopoietic cells, obtained by passing marrow through nylon wool columns, the LBMC stromal cells could support long-term myelopoiesis. Conversely, transfer of MBMC stroma to LBMC conditions resulted in a cessation of myeloid growth factor secretion; on seeding these cultures with nylon wool-passed marrow, B lymphopoiesis, but not myelopoiesis, initiated. These findings indicate that the stroma in the different LTBMC are not restricted in their hemopoietic support capacity but are sensitive to culture conditions in a manner that may affect the type of microenvironment formed.
长期骨髓培养（LTBMC）中的造血作用依赖于形成体外造血微环境的贴壁基质细胞。髓系骨髓培养（MBMC）对髓系造血最为适宜，而淋巴系骨髓培养（LBMC）仅支持B淋巴细胞生成。本文报道的实验对这两种培养进行了比较分析，以确定建立体外培养的基质细胞是否分别局限于支持髓系造血或淋巴系造血，并研究不同的培养条件如何影响基质细胞生理学。为便于此分析，通过用抗生素霉酚酸处理LTBMC，制备了MBMC和LBMC基质的纯化群体；这导致造血细胞被清除，同时保留了功能性基质的纯化群体。在MBMC条件下制备和维持的基质细胞培养物分泌刺激粒细胞-巨噬细胞集落生长的髓系生长因子，而从纯化的LBMC基质培养物中未检测到此类活性。然而，这并非由于LBMC基质无法介导此功能。将LBMC基质培养物转移至MBMC条件导致髓系生长因子分泌的诱导。当在这些条件下接种通过尼龙棉柱过滤获得的基质细胞耗尽的造血细胞群体时，LBMC基质细胞可支持长期髓系造血。相反，将MBMC基质转移至LBMC条件导致髓系生长因子分泌停止；在用尼龙棉过滤的骨髓接种这些培养物时，启动了B淋巴细胞生成而非髓系造血。这些发现表明，不同LTBMC中的基质在其造血支持能力上不受限制，但对培养条件敏感，其方式可能会影响形成的微环境类型。
