Zhang Xinyi, Zhu Zhongge, Zhai Peijie, Lv Peng, Yang You, Cheng Chuanhang, Wang Busen, Fang Ting, Zhang Guanying, Chi Xiangyang, Li Jianmin, Chen Wei, Dong Yunzhu
College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, China.
Laboratory of Advanced Biotechnology, Beijing Institute of Biotechnology, Beijing, China.
Front Immunol. 2025 Jun 19;16:1613945. doi: 10.3389/fimmu.2025.1613945. eCollection 2025.
Human adenovirus serotype 4 (HAdV-4) is an epidemic pathogen associated with severe acute respiratory disease (ARD) in both pediatric and adult populations. Currently, no available vaccine or therapeutic interventions specifically targeting adenoviruses are available.
In this study, we isolated peripheral blood mononuclear cells (PBMCs) from HAdV-4 infected donors and generated fully human monoclonal antibodies using single-cell PCR technology. The antibodies were first characterized for their neutralization efficacy both in vitro and in vivo. Subsequently, we predicted key functional residues through structural modeling of antigen-antibody complexes and validated their roles via mutagenesis studies. Finally, the mechanism of intracellular neutralization of antibodies was explored.
Through systematic screening, we successfully isolated seven antibodies with specific binding activity, among which monoclonal antibodies (mAbs) 2CF4 and 4AC3 exhibited potent neutralizing capacity against HAdV-4. Notably, we modeled adenoviral lethality using Stat1 transgenic mice, mAb 2CF4 conferred full protection against HAdV-4 infection in Stat1 transgenic mice. We identified critical amino acid residues, R99, R102 and T104 aa, of mAb 2CF4 by structural prediction of the antigen-antibody complex. Furthermore, the mAb 2CF4 neutralize the HAdV-4 through the interaction with the widely expressed cytoplasmic Fc-binding protein TRIM21.
Overall, mAb 2CF4 represents a promising candidate for safe and effective prophylactic and therapeutic strategies against HAdV-4 infection.
人类腺病毒4型（HAdV-4）是一种在儿童和成人中均与严重急性呼吸道疾病（ARD）相关的流行病原体。目前，尚无专门针对腺病毒的可用疫苗或治疗干预措施。
在本研究中，我们从感染HAdV-4的供体中分离出外周血单核细胞（PBMC），并使用单细胞PCR技术生成了完全人源单克隆抗体。首先在体外和体内对这些抗体的中和效力进行了表征。随后，我们通过抗原-抗体复合物的结构建模预测了关键功能残基，并通过诱变研究验证了它们的作用。最后，探索了抗体细胞内中和的机制。
通过系统筛选，我们成功分离出七种具有特异性结合活性的抗体，其中单克隆抗体（mAb）2CF4和4AC3对HAdV-4表现出强大的中和能力。值得注意的是，我们使用Stat1转基因小鼠模拟腺病毒致死性，mAb 2CF4在Stat1转基因小鼠中对HAdV-4感染提供了完全保护。通过抗原-抗体复合物的结构预测，我们确定了mAb 2CF4的关键氨基酸残基R99、R102和T104氨基酸。此外，mAb 2CF4通过与广泛表达的细胞质Fc结合蛋白TRIM21相互作用来中和HAdV-4。
总体而言，mAb 2CF4是针对HAdV-4感染的安全有效预防和治疗策略的有希望的候选者。
