Mutants of lymphotoxin-alpha with augmented cytotoxic activity via TNFR1 for use in cancer therapy
Mutants of lymphotoxin-alpha with augmented cytotoxic activity via TNFR1 for use in cancer therapy
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通过 TNFR1 增强细胞毒活性的α淋巴毒素突变体用于癌症治疗
DOI：
10.1016/j.cyto.2012.11.005
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发表时间：
2013
期刊：
影响因子：
3.8
通讯作者：
Tsunoda S. et al.
中科院分区：
文献类型：
--
作者：
Morishige T.;Tsunoda S. et al.
淋巴细胞因子-α (LTα)是一种很有希望用于癌症治疗的候选者。然而，LTα在体内的不稳定性和肿瘤坏死因子受体1 （TNFR1）介导的LTα生物活性水平不足限制了其治疗潜力。在这里，我们使用噬菌体展示技术创建了具有增加tnfr1介导的生物活性的LTα突变体。我们构建了一个噬菌体文库，显示具有随机氨基酸残基的赖氨酸缺乏的LTα结构变体。经过亲和筛选，我们筛选了3个赖氨酸缺乏的LTα突变体克隆，并鉴定出一个LTα突变体，其tnfr1介导的生物活性是野生型LTα (wtLTα)的32倍。与wtLTα相比，所选择的克隆由于缓慢的解离而不是快速的结合而对TNFR1表现出增强的亲和力。相比之下，突变体仅显示出tnfr2介导的wtLTα活性的4倍。此外，LTα突变体强烈而快速地激活了诱导tnfr1介导的细胞死亡的caspase，而突变体和wtLTα在相似程度上激活了核因子- κ B。我们的数据表明，LTα与TNFR1结合的动力学在信号转导模式中起着重要作用，具有增强生物活性的TNFR1选择性LTα突变体将是癌症治疗的优越候选者。
The cytokine lymphotoxin-α (LTα) is a promising candidate for use in cancer therapy. However, the instability of LTαin vivo and the insufficient levels of tumor necrosis factor receptor 1 (TNFR1)-mediated bioactivity of LTα limit its therapeutic potential. Here, we created LTα mutants with increased TNFR1-mediated bioactivity by using a phage display technique. We constructed a phage library displaying lysine-deficient structural variants of LTα with randomized amino acid residues. After affinity panning, we screened three clones of lysine-deficient LTα mutant, and identified a LTα mutant with TNFR1-mediated bioactivity that was 32times that of the wild-type LTα (wtLTα). When compared with wtLTα, the selected clone showed augmented affinity to TNFR1 due to slow dissociation rather than rapid association. In contrast, the mutant showed only 4times the TNFR2-mediated activity of wtLTα. In addition, the LTα mutant strongly and rapidly activated caspases that induce TNFR1-mediated cell death, whereas the mutant and wtLTα activated nuclear factor-kappa B to a similar extent. Our data suggest that the kinetics of LTα binding to TNFR1 play an important role in signal transduction patterns, and a TNFR1-selective LTα mutant with augmented bioactivity would be a superior candidate for cancer therapy.