Selection of an ASIC1a-blocking combinatorial antibody that protects cells from ischemic death
Selection of an ASIC1a-blocking combinatorial antibody that protects cells from ischemic death
复制标题
选择可保护细胞免遭缺血性死亡的 ASIC1a 阻断组合抗体
DOI：
10.1073/pnas.1807233115
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发表时间：
2018-08-07
影响因子：
11.1
通讯作者：
Lerner, Richard A.
中科院分区：
文献类型：
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作者：
Qiang, Min;Dong, Xue;Lerner, Richard A.
酸敏感离子通道（ASICs）已成为治疗疼痛、中风等疾病重要但颇具挑战的治疗靶点。开发治疗药物的一种途径可能涉及制备针对这些通道的功能性抗体。为筛选此类抗体，我们采用了组装在纳米圆盘内的通道，以使目标ASIC1a的构象尽可能接近其在质膜中的天然状态。这种方法能够筛选出以剂量依赖方式抑制酸诱导通道开放的功能性抗体。除调节pH值外，这些抗体还能阻断包括钙离子在内的阳离子转运，从而在体外和体内预防酸诱导的细胞死亡。作为使用这些抗体在体内调节离子通道的概念验证，我们证明了它们能有效保护脑细胞在缺血性中风后免于死亡。因此，本文所述方法应具有通用性，从而能够筛选针对其他重要ASICs的抗体，比如涉及疼痛、神经退行性变及其他病症的ASICs。
Significance Unfortunately, the need for ideal medical treatment of acute ischemic stroke is still largely unmet. One of the contributing factors to the deleterious neuronal death is the opening of acid-sensing ion channels (ASICs) at reduced pH, which in turn, activates other calcium-permeable channels that initiate the catastrophic cascade. Here, we report the discovery of an antibody that blocks the ASIC1a with high specificity and potency. Infusion of this antibody reduces the damaged area from brain ischemia in the murine stroke model. We hypothesize that using antibodies to target ASIC1a is a valid approach for future stroke therapy. The antibody that we report here has the potential to be further developed as drug candidate. Acid-sensing ion channels (ASICs) have emerged as important, albeit challenging therapeutic targets for pain, stroke, etc. One approach to developing therapeutic agents could involve the generation of functional antibodies against these channels. To select such antibodies, we used channels assembled in nanodiscs, such that the target ASIC1a has a configuration as close as possible to its natural state in the plasma membrane. This methodology allowed selection of functional antibodies that inhibit acid-induced opening of the channel in a dose-dependent way. In addition to regulation of pH, these antibodies block the transport of cations, including calcium, thereby preventing acid-induced cell death in vitro and in vivo. As proof of concept for the use of these antibodies to modulate ion channels in vivo, we showed that they potently protect brain cells from death after an ischemic stroke. Thus, the methodology described here should be general, thereby allowing selection of antibodies to other important ASICs, such as those involved in pain, neurodegeneration, and other conditions.