The NF-κB cascade is important in Bcl-xL expression and for the anti-apoptotic effects of the CD28 receptor in primary human CD4+ lymphocytes
The NF-κB cascade is important in Bcl-xL expression and for the anti-apoptotic effects of the CD28 receptor in primary human CD4+ lymphocytes
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DOI：
10.4049/jimmunol.165.4.1743
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发表时间：
2000-08-15
影响因子：
4.4
通讯作者：
Nel, AE
中科院分区：
文献类型：
--
作者：
Khoshnan, A;Tindell, C;Nel, AE
我们探讨了在CD 28共刺激过程中，NF-κ B通路在原代人CD 4（+）T淋巴细胞存活中的作用，用四环素调节的逆转录病毒转导增殖的CD 4（+）T细胞，该逆转录病毒编码显性干扰、抗降解的I-κ B α。（kappa B α因子抑制剂）突变体诱导细胞凋亡，使用DNA阵列，我们发现Bcl-x（L）在许多早期CD 28诱导基因中是一个突出的抗凋亡成员。近端Bcl-x（L）启动子的1.2 kb片段与荧光素酶报告基因连接，对Jurkat细胞中的CD 3/CD 28刺激有反应。NF-κ B位点-840附近的突变减少，而I-κ B激酶β（IKK β）的异位表达增强了报告基因的活性。水杨酸钠和环戊烯酮PG是IKK β的直接抑制剂，可干扰Bcl-x（L）启动子的激活并诱导CD 28共刺激的CD 4（+）T细胞凋亡。此外，水杨酸阻断了与Bcl-x（L）启动子中的NF-κ B结合位点结合的NF-κ B B因子的核定位，以及Bcl-x（L）蛋白的表达。HuT-78是一种具有组成性NF-κ B活性的淋巴母细胞样T细胞系，含有升高水平的Bcl-x（L）蛋白，并且与增殖的CD 4（+）T细胞类似，对凋亡刺激如抗Fas和TNF-α具有抗性。相反，相同的刺激容易诱导Jurkat T细胞克隆的凋亡，而没有可检测到的Bcl-x（L）表达。Jurkat BMS 2细胞在线粒体膜电位的崩溃和线粒体中超氧化物的产生方面也不同于HuT-78。总之，这些数据表明，CD 3/CD 28诱导的IKK β活化和Bcl-x（L）表达促进了原代人CD 4 + T淋巴细胞的存活。
We explored the role of the NF-kappa B pathway in the survival of primary human CD4(+) T lymphocytes during CD28 costimulation, Transduction of proliferating CD4(+) T cells with a tetracycline-regulated retrovirus encoding for a dominant-interfering, degradation-resistant I-kappa B alpha (inhibitor of kappa B alpha factor) mutant induced apoptosis, Using DNA arrays, we show that Bcl-x(L) features as a prominent anti-apoptotic member among a number of early CD28-inducible genes. A 1.2-kb segment of the proximal Bcl-x(L) promoter, linked to a luciferase reporter, responded to CD3/CD28 stimulation in Jurkat cells. Mutation of an NF-kappa B site around -840 decreased, while ectopic expression of I-kappa B kinase-beta (IKK beta) enhanced reporter gene activity. Na+-salicylate and cyclopentenone PGs, direct inhibitors of IKK beta, interfered in the activation of the Bcl-x(L) promoter and induced apoptosis in CD28-costimulated CD4(+) T cells. Moreover, salicylate blocked nuclear localization of NF-kappa B factors that bind to the NF-kappa B binding site in the Bcl-x(L) promoter, as well as the expression of Bcl-x(L) protein. HuT-78, a lymphoblastoid T cell line with constitutive NF-kappa B activity, contained elevated levels of Bcl-x(L) protein and, similar to proliferating CD4(+) T cells, was resistant to apoptotic stimuli such as anti-Fas and TNF-alpha, In contrast, the same stimuli readily induced apoptosis in a Jurkat T cell clone with no detectable Bcl-x(L) expression. Jurkat BMS2 cells also differed from HuT-78 in collapse of mitochondrial membrane potential and superoxide generation in the mitochondrium. Taken together, these data demonstrate that CD3/CD28-induced activation of IKK beta and expression of Bcl-x(L) promote the survival of primary human CD4+ T lymphocytes.