A mitochondrial membrane protein defined by a novel monoclonal antibody is preferentially detected in apoptotic cells.
A mitochondrial membrane protein defined by a novel monoclonal antibody is preferentially detected in apoptotic cells.
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DOI：
10.4049/jimmunol.157.9.3980
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发表时间：
1996-11
影响因子：
4.4
通讯作者：
Chen-Yu Zhang;Z. Ao;A. Seth;S. Schlossman
中科院分区：
文献类型：
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作者：
Chen-Yu Zhang;Z. Ao;A. Seth;S. Schlossman
最近对调节细胞凋亡的基因及其产物的鉴定刺激了对程序性细胞死亡的生物学和分子理解的研究。在本研究中，通过用凋亡的 Jurkat 细胞对小鼠进行免疫接种，产生了一组针对垂死细胞的单克隆抗体。其中一种抗体，抗 7A6，被发现与凋亡细胞发生反应。使用 ELISA 或流式细胞术，在正常或洋地黄皂苷通透的人外周血淋巴细胞和测试的许多造血细胞系中几乎观察不到抗 7A6 的反应性。然而，当这些细胞通过辐射或细胞凋亡诱导剂处理而诱导细胞凋亡时，抗体与这些细胞发生强烈反应。细胞分选和DNA片段化实验表明，7A6阳性细胞（而非7A6阴性细胞）具有明显的凋亡细胞特征的DNA片段。通过免疫印迹，在还原条件下，抗 7A6 在从凋亡细胞制备的细胞裂解物中检测到 38 kDa 的蛋白条带。免疫电镜显示 7A6 Ag 定位于凋亡 Jurkat 细胞的线粒体膜上。这些结果表明，抗7A6在线粒体膜蛋白上定义了一个新的表位，该表位似乎暴露在经历凋亡的细胞上，表明7A6分子可能参与凋亡细胞死亡的分子级联。
Studies toward the biologic and molecular understanding of programmed cell death have been stimulated by the recent identification of genes and their products that regulate apoptosis. A panel of mAbs has been raised against dying cells in the present study by immunizing mice with apoptotic Jurkat cells. One of these Abs, anti-7A6, was found to react with apoptotic cells. Using ELISA or flow cytometry, little reactivity of anti-7A6 was observed in normal or digitonin-permeabilized human peripheral blood lymphocytes and a number of hemopoietic cell lines tested. The Ab, however, strongly reacted with these cells when they were induced to undergo apoptosis by irradiation or treatment with apoptosis-inducing agents. Cell sorting and DNA fragmentation experiments revealed that 7A6-positive cells, but not 7A6-negative cells, had apparent DNA fragments characteristic of cells undergoing apoptosis. By immunoblot, under reducing conditions, anti-7A6 detected a 38-kDa protein band in the cell lysates prepared from apoptotic cells. Immunoelectron microscopy showed the 7A6 Ag to be localized to the membrane of mitochondria in apoptotic Jurkat cells. These results indicate that anti-7A6 defines a novel epitope on the mitochondrial membrane protein that appears to be exposed on cells undergoing apoptosis, suggesting that the 7A6 molecule may be involved in the molecular cascade of apoptotic cell death.