Blokhina Elena A, Mardanova Eugenia S, Stepanova Liudmila A, Tsybalova Liudmila M, Ravin Nikolai V
Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow 101000, Russia.
Research Institute of Influenza, Russian Ministry of Health, St. Petersburg 23805, Russia.
Plants (Basel). 2020 Jan 29;9(2):162. doi: 10.3390/plants9020162.
The development of recombinant influenza vaccines with broad spectrum protection is an important task. The combination of conservative viral antigens, such as M2e, the extracellular domain of the transmembrane protein M2, and conserved regions of the second subunit of hemagglutinin (HA), provides an opportunity for the development of universal influenza vaccines. Immunogenicity of the antigens could be enhanced by fusion to bacterial flagellin, the ligand for Toll-like receptor 5, acting as a powerful mucosal adjuvant. In this study, we report the transient expression in plants of a recombinant protein comprising flagellin of fused to the conserved region of the second subunit of HA (76-130 a.a.) of the first phylogenetic group of influenza A viruses and four tandem copies of the M2e peptide. The hybrid protein was expressed in plants using the self-replicating potato virus X-based vector pEff up to 300 µg/g of fresh leaf tissue. The intranasal immunization of mice with purified fusion protein induced high levels of M2e-specific serum antibodies and provided protection against lethal challenge with influenza A virus strain A/Aichi/2/68(H3N2). Our results show that M2e and hemagglutinin-derived peptide can be used as important targets for the development of a plant-produced vaccine against influenza.
开发具有广谱保护作用的重组流感疫苗是一项重要任务。保守的病毒抗原，如跨膜蛋白M2的胞外域M2e以及血凝素（HA）第二亚基的保守区域相结合，为开发通用流感疫苗提供了契机。通过与细菌鞭毛蛋白融合可增强抗原的免疫原性，鞭毛蛋白是Toll样受体5的配体，可作为一种强大的黏膜佐剂。在本研究中，我们报道了一种重组蛋白在植物中的瞬时表达，该重组蛋白包含与甲型流感病毒第一进化组HA第二亚基保守区域（76 - 130个氨基酸）融合的鞭毛蛋白以及四个串联的M2e肽拷贝。使用基于自我复制的马铃薯X病毒载体pEff在植物中表达该杂交蛋白，其表达量高达300μg/g鲜叶组织。用纯化的融合蛋白对小鼠进行鼻内免疫可诱导产生高水平的M2e特异性血清抗体，并提供针对甲型流感病毒株A/ Aichi/2/68（H3N2）致死性攻击的保护作用。我们的结果表明，M2e和血凝素衍生肽可作为开发植物源流感疫苗的重要靶点。
