Broome H E, Dargan C M, Brunner T, Green D R
Department of Pathology, University of California, San Diego, CA 92093,
Cell Death Differ. 1998 Mar;5(3):200-5. doi: 10.1038/sj.cdd.4400329.
T lymphocytes have variable sensitivity to anti-CD95 which does not correlate closely with the level of CD95 expressed. To investigate this phenomenon, we screened murine T lymphocyte cultures for their sensitivity to anti-CD95. Subclones of the S49.1 cells showed widely variable sensitivity to anti-CD95 but similar levels of CD95. The resistant clones became sensitive after treatment with actinomycin D suggesting that they expressed resistance protein(s) with a high turnover relative to the CD95 apoptosis induction machinery. Our data suggest that the resistance protein(s) are not Bcl-2, Bcl-x, Fap-1 or Bag-1. Forced, increased expression of CD95 made most of the resistant cells more sensitive, but some remained resistant suggesting that the expression of the resistant protein(s) is heterogeneous and that increased CD95 levels does not always overcome the resistance.
T淋巴细胞对抗CD95的敏感性各不相同，且与CD95的表达水平并无紧密关联。为探究此现象，我们对小鼠T淋巴细胞培养物进行筛选，以检测其对抗CD95的敏感性。S49.1细胞的亚克隆对抗CD95的敏感性差异很大，但CD95水平相似。用放线菌素D处理后，抗性克隆变得敏感，这表明相对于CD95凋亡诱导机制，它们表达的抗性蛋白具有较高的更新率。我们的数据表明，抗性蛋白不是Bcl-2、Bcl-x、Fap-1或Bag-1。强制增加CD95的表达使大多数抗性细胞变得更敏感，但仍有一些细胞保持抗性，这表明抗性蛋白的表达是异质性的，且CD95水平的增加并不总能克服抗性。
