体外培养人骨髓基质细胞的超微结构

ULTRASTRUCTURE OF HUMAN MARROW-DERIVED STROMAL CELLS

体外培养人骨髓基质细胞的组成及功能与人体造血微环境相似，可作为研究人体造血微环境的良好模型。选择体外培养第４周的人骨髓基质细胞层，经固定、脱水、原位包埋、超薄切片染色后电镜观察。结果：可见基质层由３类基质细胞及ＥＣＭ组成。巨噬样细胞样基质细胞浆内可见ＣＩ；基质细胞表面ＥＣＭ包含胶原纤维；内皮细胞样基质细胞间可见细胞间连接，但这种连接未见于造血祖细胞及其他基质细胞间。结论：人骨髓体外培养基质细胞超微结构与人体及小鼠骨髓微环境既有相似也有不同处，其差异可能由于体内外不同生长条件所引起。

PURPOSE The ultrastructures of human marrow-derived stromal cells were observed under transmission electro-microscope(TEM)as a model for studying the human hemopoietic micro-circumstance.METHODS The area fully-covered with 4-weeks-old human marrow-derived stromal cells were selected under light microscope. After fixation wth glutaraldehyde and post-fixation with OsO4 the specimens were dehydrated with graded alcohol, and embeded in situ with Epon 618. Blocks were thin-sectioned. Sections were staining with uranyl acetate and lead citrate and examined in TEM.RESULTS The ultramicroscopic structure of human marrow derived stromal layer is constituted in 3 kinds of stromal layer cells and extra cell matrix(ECM). Crystalloid inclusions were observed in the cytoplasm of macrophage-like stromal cells; over the surface of the stromal cells, there were extracellural matrix contanining collagen fibrils, and some connectional structures were observed between endothelial-like stromal cells, but not between stromal cells and hemopoietic progenitors. CONCLUSIONS The ultrastructures of human marrow-derived stromal cells and human or mice's marrow stromal cells in vivo, some were very alike some were different. The growth conditions between in vivo and in vitro may be the cause of the difference.