Ralphs J R, Evans L, Ali S Y
Experimental Pathology Unit, Institute of Orthopaedics, Stanmore, Middlesex, United Kingdom.
Cell Tissue Res. 1988 Nov;254(2):393-8. doi: 10.1007/BF00225811.
Separation of fractions enriched in hypertrophic cells and proliferative cells has been achieved by density gradient centrifugation of cells from collagenase digests of rabbit epiphyseal cartilage. Concentrated suspensions of cells are centrifuged on a continuous Percoll density gradient. Hypertrophic cells remain in the upper part of the gradient and proliferative zone cells move to the lower regions. The resultant fractions show differences in mean cell diameter, alkaline phosphatase activity, morphology and synthetic activity in culture. Fractions rich in hypertrophic cells contain larger cells and more alkaline phosphatase activity than those enriched in proliferative cells. In culture the hypertrophic cells flatten as large irregular polygonal cells, whereas proliferative fractions form smaller spindle-shaped cells. In micromass culture hypertrophic fractions incorporate less 35S-sulphate and 14C-proline, and less tritiated thymidine than do proliferative fractions. These results suggest a general reduction in matrix and DNA synthesis with the attainment of the fully differentiated hypertrophic state, coincident with the expression of alkaline phosphatase activity and mineralisation of the cartilage matrix.
通过对兔骺软骨胶原酶消化产物中的细胞进行密度梯度离心，已实现富含肥大细胞和增殖细胞的组分的分离。将细胞浓缩悬浮液在连续的Percoll密度梯度上进行离心。肥大细胞留在梯度的上部，增殖区细胞移至下部区域。所得组分在培养中的平均细胞直径、碱性磷酸酶活性、形态和合成活性方面存在差异。富含肥大细胞的组分比富含增殖细胞的组分含有更大的细胞和更多的碱性磷酸酶活性。在培养中，肥大细胞扁平成为大的不规则多边形细胞，而增殖组分形成较小的纺锤形细胞。在微团培养中，肥大组分比增殖组分掺入的35S-硫酸盐和14C-脯氨酸以及氚标记的胸腺嘧啶核苷更少。这些结果表明，随着完全分化的肥大状态的实现，基质和DNA合成普遍减少，这与碱性磷酸酶活性的表达和软骨基质的矿化同时发生。
