Benya P D, Jaffe S, Raffo A
Arch Biochem Biophys. 1984 Jul;232(1):323-36. doi: 10.1016/0003-9861(84)90548-4.
Cartilage slices maintained in organ culture have been shown to develop an enhanced capacity to respond to serum. The response was measured at the initiation of culture and after 3 and 7 days of culture in medium containing an inhibitor of DNA synthesis and 0, 1, or 16% serum. At these times, cartilage slices were washed to remove serum and inhibitor, and then exposed to various concentrations of serum for evaluation of DNA and proteoglycan synthesis. The range of the derived dose-response curves and the indicated sensitivity to low serum concentrations were the parameters used to evaluate the response capacity. Response capacity increased gradually, reaching a maximum after 8 days of culture. Considerable enhancement was obtained after maintenance in the absence of serum using both DNA and proteoglycan synthesis as markers. Additional, graded enhancement of response capacity was obtained when the cartilage slices were maintained in 1 or 16% serum. The effects of maintenance in serum were much greater when DNA synthesis rather than proteoglycan synthesis was used to measure the response. However, this serum-dependent enhancement was only prominent when ascorbate was present during the dose-response assay. Ascorbate caused a similar but less-marked increase in sensitivity to serum when proteoglycan synthesis was measured. The possibility that ascorbate may function as a cofactor during the progression phase of cell proliferation is discussed.
已证明在器官培养中维持的软骨切片对血清的反应能力增强。在含有DNA合成抑制剂和0%、1%或16%血清的培养基中培养开始时以及培养3天和7天后测量反应。在这些时间点，将软骨切片洗涤以去除血清和抑制剂，然后暴露于各种浓度的血清中以评估DNA和蛋白聚糖的合成。导出的剂量反应曲线范围和对低血清浓度的指示敏感性是用于评估反应能力的参数。反应能力逐渐增加，在培养8天后达到最大值。以DNA和蛋白聚糖合成作为标志物，在无血清条件下维持后获得了相当大的增强。当软骨切片在1%或16%血清中维持时，反应能力得到了额外的分级增强。当用DNA合成而不是蛋白聚糖合成来测量反应时，血清维持的效果要大得多。然而，这种血清依赖性增强仅在剂量反应测定期间存在抗坏血酸时才显著。当测量蛋白聚糖合成时，抗坏血酸对血清的敏感性也有类似但不太明显的增加。讨论了抗坏血酸在细胞增殖进展阶段可能作为辅助因子发挥作用的可能性。
