Fry M, Weisman-Shomer P
Cell Biol Int Rep. 1977 Sep;1(5):399-407. doi: 10.1016/0309-1651(77)90073-x.
Proliferation of senescent cultured chick fibroblasts is arrested at densities that are 3-4 fold lower than densities inhibiting growth of young cells. The effects of density and growth rate of young and aged cultures on the accessibility of their surface proteins to external iodination were studied. LETS glycoprotein and a protein of 110,000 daltons are the major iodinated proteins of resting, highly dense and of sparse young cells, respectively. By contrast, LETS is minimally exposed on undividing, relatively disperse old cells. Therefore, exposure of LETS is correlated with cell density rather than with growth rate.
衰老的培养鸡成纤维细胞在密度比抑制年轻细胞生长的密度低3 - 4倍时停止增殖。研究了年轻和衰老培养物的密度和生长速率对其表面蛋白对外源碘化可及性的影响。LETS糖蛋白和一种110,000道尔顿的蛋白分别是静止、高密度和稀疏年轻细胞的主要碘化蛋白。相比之下，LETS在不分裂、相对分散的衰老细胞上暴露最少。因此，LETS的暴露与细胞密度相关，而非与生长速率相关。
