Tsuji Y, Ide T, Ishibashi S
Exp Cell Res. 1983 Mar;144(1):165-9. doi: 10.1016/0014-4827(83)90450-0.
Senescent human diploid fibroblasts, TIG-1, had labelling indices of about 0.5-3% when labelled with [3H]thymidine for 3 days in fresh medium containing 10% fetal bovine serum. When these cells were infected with SV40, the percentage of nuclei incorporating [3H]thymidine increased by about 10-fold. The frequency of T-antigen-positive cells and that of [3H]thymidine-incorporating cells were almost the same. About 80% of T-antigen-positive cells were also positive to incorporation of [3H]thymidine, and the same result was obtained in infected young cells. These results indicated that senescent human diploid cells which are brought to synthesize T-antigen always initiate DNA synthesis as young cells do. The characteristics of senescent cells as compared with younger cells was low incidence of T-antigen-positive cells after infection. The basis of low susceptibility of senescent cells to initiate DNA synthesis by SV40 infection thus seems to be concerned with an event after the adsorption of virus, but before the synthesis of a detectable amount of T-antigen.
衰老的人二倍体成纤维细胞TIG - 1，在含有10%胎牛血清的新鲜培养基中用[³H]胸腺嘧啶核苷标记3天时，标记指数约为0.5 - 3%。当这些细胞感染SV40时，掺入[³H]胸腺嘧啶核苷的细胞核百分比增加了约10倍。T抗原阳性细胞的频率与掺入[³H]胸腺嘧啶核苷的细胞频率几乎相同。约80%的T抗原阳性细胞对[³H]胸腺嘧啶核苷的掺入也呈阳性，并且在感染的年轻细胞中也得到了相同的结果。这些结果表明，被诱导合成T抗原的衰老人二倍体细胞总是像年轻细胞一样启动DNA合成。与年轻细胞相比，衰老细胞的特征是感染后T抗原阳性细胞的发生率较低。因此，衰老细胞对SV40感染启动DNA合成敏感性低的基础似乎与病毒吸附后但在合成可检测量的T抗原之前的一个事件有关。
