Shen V, Rifas L, Kohler G, Peck W A
Endocrinology. 1985 Mar;116(3):920-5. doi: 10.1210/endo-116-3-920.
Chondrocytes isolated from the calvaria of rat fetuses proliferate and form cartilage when cultured in a chemically defined, serum-free medium, suggesting that they may elaborate self-regulatory factors. Conditioned media obtained from these chondrocytes stimulated DNA synthesis and proliferation when added to separate cultures of chondrocytes and the closely related osteoblast-like cells, but were not very effective in skin fibroblasts isolated from the same fetuses, as judged by [3H]thymidine incorporation and cell proliferation. Chondrocyte-conditioned medium also promoted chondrocyte differentiation, augmenting 35SO4 incorporation, and the accumulation of type II collagen and cartilage-specific proteoglycan. Stimulation of growth and differentiation appears to be attributable to separate activities, released into the medium sequentially by the cultured chondrocytes during their proliferation and maturation phases. Media obtained from growing chondrocytes stimulated growth, but had little effect on 35SO4 incorporation. Media obtained from mature cultures promoted growth as well as 35SO4 incorporation. The mitogenic and sulfation activities were trypsin inhibitable, but exhibited different solubility characteristics and striking differences in their patterns of elution from gel filtration columns. These results suggest that chondrocytes elaborate autostimulatory peptides, the biological activities of which mirror, at least in part, the developmental stage of the donor cells.
从大鼠胎儿颅骨分离出的软骨细胞，在化学成分明确的无血清培养基中培养时会增殖并形成软骨，这表明它们可能会分泌自我调节因子。当将这些软骨细胞的条件培养基添加到软骨细胞和密切相关的成骨细胞样细胞的单独培养物中时，会刺激DNA合成和细胞增殖，但从相同胎儿分离出的皮肤成纤维细胞对其反应不佳，这是通过[3H]胸苷掺入和细胞增殖来判断的。软骨细胞条件培养基还促进软骨细胞分化，增加35SO4掺入以及II型胶原蛋白和软骨特异性蛋白聚糖的积累。生长和分化的刺激似乎归因于不同的活性，这些活性在培养的软骨细胞增殖和成熟阶段依次释放到培养基中。从正在生长的软骨细胞获得的培养基刺激生长，但对35SO4掺入影响很小。从成熟培养物获得的培养基促进生长以及35SO4掺入。促有丝分裂和硫酸化活性可被胰蛋白酶抑制，但表现出不同的溶解性特征以及从凝胶过滤柱洗脱的模式有显著差异。这些结果表明，软骨细胞分泌自刺激肽，其生物活性至少部分反映了供体细胞的发育阶段。
