Nagler-Anderson C, Lichtenheld M, Eisen H N, Podack E R
Department of Biology, Massachusetts Institute of Technology, Cambridge 02139.
J Immunol. 1989 Dec 1;143(11):3440-3.
Considerable evidence indicates that cloned CTL cell lines kill target cells by releasing toxic granules that contain a cytolytic protein, called perforin, and several serine esterases (granzymes A to F). However, primary CTL, such as the highly cytolytic peritoneal exudate lymphocyte (PEL) cell population, have been found by a hemolytic assay to have no perforin, or perhaps only borderline levels of that protein, suggesting that these cells use a different lytic mechanism. To determine whether or not primary CTL express the perforin gene, we have here compared mRNA from PEL CTL and from a cloned CTL cell line, 2C, by Northern blot analysis using a perforin cDNA probe. CD8+ PEL CTL contain approximately 30% of the amount of perforin message present in 2C. Moreover, depletion of CD8+ T cells from the total peritoneal exudate cell population removes both cytolytic activity and perforin message. We have previously shown that PEL CTL elicit the same changes in target cells as cloned CTL cell lines and are resistant to lysis by the toxic granules purified from these cells lines. Taken together these results are consistent with the view that primary CTL, as well as long term cloned CTL cell lines, exercise their cytolytic activity by means of perforin.
大量证据表明，克隆的细胞毒性T淋巴细胞（CTL）细胞系通过释放有毒颗粒来杀死靶细胞，这些颗粒含有一种称为穿孔素的溶细胞蛋白和几种丝氨酸酯酶（颗粒酶A至F）。然而，通过溶血试验发现，原代CTL，如高细胞毒性的腹膜渗出淋巴细胞（PEL）细胞群体，没有穿孔素，或者该蛋白的水平可能仅处于临界水平，这表明这些细胞使用不同的裂解机制。为了确定原代CTL是否表达穿孔素基因，我们在这里使用穿孔素cDNA探针，通过Northern印迹分析比较了PEL CTL和克隆的CTL细胞系2C的mRNA。CD8 + PEL CTL中穿孔素信息的含量约为2C中的30%。此外，从总的腹膜渗出细胞群体中去除CD8 + T细胞会消除细胞溶解活性和穿孔素信息。我们之前已经表明，PEL CTL在靶细胞中引起的变化与克隆的CTL细胞系相同，并且对从这些细胞系中纯化的有毒颗粒的裂解具有抗性。综合这些结果与以下观点一致，即原代CTL以及长期克隆的CTL细胞系通过穿孔素发挥其细胞溶解活性。
