对培养的软骨细胞形成生长板样软骨组织的研究

Study on Reorganization of Growth-plate-like Tissue by Isolated Chondrocytes in Culture

用家兔肋软骨生长板软骨细胞，进行高密度培养，快速增殖，大量合成细胞外基质，重新构建成了在形态和代谢方面高度分化的、与生长板软骨极为相似的生长板样软骨组织。

Growth-plate cartilage was organized into four cellular zones containing resting , proliferat- ing , maturing and hypertrophic cells. Rabbit chondrocytes were isolated from growth-plate costal cartilage of 4-week-old New Zealand rabbits , and the cells were transferred into a plastic cen- trifuge tube and centrifuged. The cell pellet was incubated at 37 ℃under 5 % CO2 in air. The cul- tures were reorganized into growth plate-like tissue which could be seen 7 - 14 days after cell seeding. This growth-plate , histologically , was organized longitudinally into cellular columns and horizontally into four cellular zones containing resting , proliferating , maturing and hyper- trophic cells. The hypertrophic cells in the upper were large in size and round or oval in shape , and the proliferating and the mature chondrocytes in the lower were small in size and spherical or elongated in shape. These chondrocytes were surrounded by an extensive matrix. Biochemically , DNA content of cultures began to rise on the 2nd day after cell seeding and reached a plateau after 10 days. The uronic acid content increased from day 4 and reached the maximum on day 1 5. In contrast in the early culture , alkaline phosphatase activity was extremely low , and it began to rise on day 9 and was the highest on day 20. The sequential increase of DNA , uronic acid con- tents and alkaline phosphatase activity were analogous to the in vivo changes of growth-plate chondrocytes .