Changchun Veterinary Research Institute, Chinese Academy of Agricultural Science, Changchun 130122, China.
Chongqing Academy of Animal Sciences, Chongqing 402460, China.
Toxicol Lett. 2023 Jul 1;383:152-161. doi: 10.1016/j.toxlet.2023.06.008. Epub 2023 Jun 28.
DNA-encoded monoclonal antibodies (DMAbs) and in vivo expression of antibody therapeutics presents an innovative alternative to conventional delivery methods. Therefore, in order to prevent the lethal dose of ricin toxin (RT) and to avoid human anti-mouse antibody (HAMA) reaction, we developed the human neutralizing antibody 4-4E against RT and constructed DMAb-4-4E. The human neutralizing antibody 4-4E could neutralize RT in vitro and in vivo, while the mice in RT group all died. Using intramuscular electroporation (IM EP), antibodies were rapidly expressed in vivo within 7 days and were enriched in intestine and gastrocnemius muscle mostly. Besides, we found that DMAbs have shown a broad protective efficacy of RT poisoning prophylaxis. Driven by plasmids for IgG expression, mice were survived and the blood glucose level of mice in DMAb-IgG group returned to normal at 72 h post RT challenge, and the RT group died within 48 h. Furthermore, hindrance of protein disulfide isomerase (PDI) and accumulation of RT in endosomes were found in IgG-protected cells, revealing the possible mechanism of neutralization details. These data support the further study of RT-neutralizing monoclonal antibodies (mAbs) in the development.
DNA 编码单克隆抗体（DMAb）和体内表达的抗体疗法为传统的给药方法提供了一种创新的替代方案。因此，为了防止蓖麻毒素（RT）的致死剂量和避免人抗鼠抗体（HAMA）反应，我们开发了针对 RT 的人中和抗体 4-4E，并构建了 DMAb-4-4E。人中和抗体 4-4E 可以在体外和体内中和 RT，而 RT 组的小鼠全部死亡。使用肌内电穿孔（IM EP），抗体在 7 天内在体内迅速表达，主要在肠道和腓肠肌中富集。此外，我们发现 DMAb 对 RT 中毒预防具有广泛的保护作用。在 IgG 表达质粒的驱动下，接受 DMAb-IgG 治疗的小鼠存活，且其血糖水平在 RT 攻击后 72 小时恢复正常，而 RT 组的小鼠在 48 小时内死亡。此外，在 IgG 保护的细胞中发现了蛋白质二硫键异构酶（PDI）的阻滞和 RT 在内涵体中的积累，揭示了中和作用的可能机制。这些数据支持进一步研究 RT 中和单克隆抗体（mAb）在开发中的应用。
