A Novel Nanobody Targeting Middle East Respiratory Syndrome Coronavirus (MERS-CoV) Receptor-Binding Domain Has Potent Cross-Neutralizing Activity and Protective Efficacy against MERS-CoV.
A Novel Nanobody Targeting Middle East Respiratory Syndrome Coronavirus (MERS-CoV) Receptor-Binding Domain Has Potent Cross-Neutralizing Activity and Protective Efficacy against MERS-CoV.
复制标题
一种针对中东呼吸综合征冠状病毒（MERS-CoV）受体结合域的新型纳米抗体具有有效的交叉中和活性和针对 MERS-CoV 的保护功效
DOI：
10.1128/jvi.00837-18
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发表时间：
2018-09-15
影响因子：
5.4
通讯作者：
Zhou Y
中科院分区：
文献类型：
--
作者：
Zhao G;He L;Sun S;Qiu H;Tai W;Chen J;Li J;Chen Y;Guo Y;Wang Y;Shang J;Ji K;Fan R;Du E;Jiang S;Li F;Du L;Zhou Y
治疗发展对于预防和治疗人类和骆驼中持续的中东呼吸综合征冠状病毒感染至关重要。由于其体积小，纳米体（Nbs）作为抗病毒治疗药物具有优势（例如，高表达量和存储和运输的健壮性），但也有潜在的局限性（例如，低抗原结合亲和力和快速肾脏清除）。在这里，我们开发了特异性靶向MERS-CoV刺突蛋白受体结合域（RBD）的新型Nbs。它们以高亲和力结合到MERS-CoV RBD上的一个保守位点，阻断RBD与MERS-CoV受体的结合。通过设计c端人类Fc标签，Nbs的体内半衰期显着延长。此外，Nbs可以有效地交叉中和从人类和骆驼分离的多种中东呼吸综合征冠状病毒株的感染。fc标记的Nb还能完全保护人源化小鼠免受致命的MERS-CoV攻击。综上所述，我们的研究发现了新的Nbs，它们有望成为有效的、具有成本效益的广谱抗mers - cov治疗剂。新出现的中东呼吸综合征冠状病毒（MERS-CoV）持续感染人类和骆驼，需要采取高效、经济、广谱的策略来控制其传播。纳米体（Nbs）是来源于骆驼和鲨鱼的单结构域抗体，具有体积小、表达量高的特点，是具有潜在成本效益的抗病毒药物。在这项研究中，我们开发了一种新的中和Nb （NbMS10）和它的人- fc融合版本（NbMS10- fc），两者都靶向MERS-CoV刺突蛋白受体结合域（RBD）。我们进一步测试了它们的受体结合亲和力、识别表位、交叉中和活性、半衰期和抗MERS-CoV感染的有效性。这两种Nbs均能在酵母中高产表达，高亲和力结合MERS-CoV RBD，阻断MERS-CoV RBD与MERS-CoV受体的结合。RBD上Nbs的结合位点被定位在残基Asp539附近，该残基是受体结合界面上保守构象表位的一部分。NbMS10和NbMS10- fc对分离自人类和骆驼的不同MERS-CoV株具有很强的交叉中和活性。特别是NbMS10-Fc显著延长了体内半衰期；单剂量NbMS10-Fc可完全保护人源化小鼠免受致命的MERS-CoV攻击，显示出较高的预防和治疗效果。总的来说，本研究证明了生产具有成本效益、有效、广谱的抗MERS-CoV Nbs的可行性，并已生产出具有很大潜力的抗MERS-CoV治疗药物。治疗发展对于预防和治疗人类和骆驼的持续性中东呼吸综合征冠状病毒感染至关重要。由于其体积小，纳米体（Nbs）作为抗病毒治疗药物具有优势（例如，高表达量和存储和运输的健壮性），但也有潜在的局限性（例如，低抗原结合亲和力和快速肾脏清除）。在这里，我们开发了特异性靶向MERS-CoV刺突蛋白受体结合域（RBD）的新型Nbs。它们以高亲和力结合到MERS-CoV RBD上的一个保守位点，阻断RBD与MERS-CoV受体的结合。通过设计c端人类Fc标签，Nbs的体内半衰期显着延长。此外，Nbs可以有效地交叉中和从人类和骆驼分离的多种中东呼吸综合征冠状病毒株的感染。fc标记的Nb还能完全保护人源化小鼠免受致命的MERS-CoV攻击。综上所述，我们的研究发现了新的Nbs，它们有望成为有效的、具有成本效益的广谱抗mers - cov治疗剂。
Therapeutic development is critical for preventing and treating continual MERS-CoV infections in humans and camels. Because of their small size, nanobodies (Nbs) have advantages as antiviral therapeutics (e.g., high expression yield and robustness for storage and transportation) and also potential limitations (e.g., low antigen-binding affinity and fast renal clearance). Here, we have developed novel Nbs that specifically target the receptor-binding domain (RBD) of MERS-CoV spike protein. They bind to a conserved site on MERS-CoV RBD with high affinity, blocking RBD's binding to MERS-CoV receptor. Through engineering a C-terminal human Fc tag, the in vivo half-life of the Nbs is significantly extended. Moreover, the Nbs can potently cross-neutralize the infections of diverse MERS-CoV strains isolated from humans and camels. The Fc-tagged Nb also completely protects humanized mice from lethal MERS-CoV challenge. Taken together, our study has discovered novel Nbs that hold promise as potent, cost-effective, and broad-spectrum anti-MERS-CoV therapeutic agents. ABSTRACT The newly emerged Middle East respiratory syndrome coronavirus (MERS-CoV) continues to infect humans and camels, calling for efficient, cost-effective, and broad-spectrum strategies to control its spread. Nanobodies (Nbs) are single-domain antibodies derived from camelids and sharks and are potentially cost-effective antivirals with small size and great expression yield. In this study, we developed a novel neutralizing Nb (NbMS10) and its human-Fc-fused version (NbMS10-Fc), both of which target the MERS-CoV spike protein receptor-binding domain (RBD). We further tested their receptor-binding affinity, recognizing epitopes, cross-neutralizing activity, half-life, and efficacy against MERS-CoV infection. Both Nbs can be expressed in yeasts with high yield, bind to MERS-CoV RBD with high affinity, and block the binding of MERS-CoV RBD to the MERS-CoV receptor. The binding site of the Nbs on the RBD was mapped to be around residue Asp539, which is part of a conserved conformational epitope at the receptor-binding interface. NbMS10 and NbMS10-Fc maintained strong cross-neutralizing activity against divergent MERS-CoV strains isolated from humans and camels. Particularly, NbMS10-Fc had significantly extended half-life in vivo; a single-dose treatment of NbMS10-Fc exhibited high prophylactic and therapeutic efficacy by completely protecting humanized mice from lethal MERS-CoV challenge. Overall, this study proves the feasibility of producing cost-effective, potent, and broad-spectrum Nbs against MERS-CoV and has produced Nbs with great potentials as anti-MERS-CoV therapeutics. IMPORTANCE Therapeutic development is critical for preventing and treating continual MERS-CoV infections in humans and camels. Because of their small size, nanobodies (Nbs) have advantages as antiviral therapeutics (e.g., high expression yield and robustness for storage and transportation) and also potential limitations (e.g., low antigen-binding affinity and fast renal clearance). Here, we have developed novel Nbs that specifically target the receptor-binding domain (RBD) of MERS-CoV spike protein. They bind to a conserved site on MERS-CoV RBD with high affinity, blocking RBD's binding to MERS-CoV receptor. Through engineering a C-terminal human Fc tag, the in vivo half-life of the Nbs is significantly extended. Moreover, the Nbs can potently cross-neutralize the infections of diverse MERS-CoV strains isolated from humans and camels. The Fc-tagged Nb also completely protects humanized mice from lethal MERS-CoV challenge. Taken together, our study has discovered novel Nbs that hold promise as potent, cost-effective, and broad-spectrum anti-MERS-CoV therapeutic agents.