Benayahu D, Kompier R, Shamay A, Kadouri A, Zipori D, Wientroub S
Department of Cell Biology, Weizmann Institute of Science, Rehovot, Israel.
Calcif Tissue Int. 1994 Aug;55(2):120-7. doi: 10.1007/BF00297187.
The present study describes a new three-dimensional (3-D) culture system that enables the maintenance and phenotypic expression of bone marrow stromal osteoblasts. This culture substratum is advantageous in that it provides suitable conditions for attachment, growth, and differentiation of cells forming 3-D layers. The MBA-15 cell line was grown in unlimited quantities on 3-D Fibro-Cel carriers. These cells mineralized when exposed to ascorbic acid and beta-glycerophosphate (beta GP). Under these mineralization conditions, mRNA expressions of procollagen alpha 2(I) and [3H]-proline-labeled protein were increased. The expression of mRNA for osteonectin and to a lesser extent, for osteopontin was increased, whereas alkaline phosphatase and biglycan remained unaffected under similar conditions. Exposure of mineralizing cultures to dexamethasone reduced mRNA of procollagen alpha 2 (I) and osteonectin to control level. Scanning electron microscopy revealed that cells were grown along the fabric's fibers and produced collagen fibrils. Under appropriate conditions, extensive mineralization had taken place. The mineralization process involves the formation of calcospherites, and correlates with an increase in calcium content. The Fibro-Cel carriers enable formation of 3-D architecture and mineralized tissue in vitro.
本研究描述了一种新的三维（3-D）培养系统，该系统能够维持骨髓基质成骨细胞并使其表型得以表达。这种培养基质的优势在于它为形成三维层的细胞的附着、生长和分化提供了合适的条件。MBA-15细胞系在三维纤维细胞载体上可大量生长。当这些细胞暴露于抗坏血酸和β-甘油磷酸酯（β GP）时会发生矿化。在这些矿化条件下，前胶原α 2（I）的mRNA表达和[3H] - 脯氨酸标记的蛋白质增加。骨连接蛋白的mRNA表达增加，骨桥蛋白的表达在较小程度上增加，而碱性磷酸酶和双糖链蛋白聚糖在类似条件下保持不变。将矿化培养物暴露于地塞米松可使前胶原α 2（I）和骨连接蛋白的mRNA降至对照水平。扫描电子显微镜显示细胞沿着织物纤维生长并产生胶原纤维。在适当条件下，发生了广泛的矿化。矿化过程涉及球晶的形成，并与钙含量的增加相关。纤维细胞载体能够在体外形成三维结构和矿化组织。
