Borgoyakova M B, Karpenko L I, Rudometov A P, Shanshin D V, Isaeva A A, Nesmeyanova V S, Volkova N V, Belenkaya S V, Murashkin D E, Shcherbakov D N, Volosnikova E A, Starostina E V, Orlova L A, Danilchenko N V, Zaikovskaya A V, Pyankov O V, Ilyichev A A
Vector State Research Center of Virology and Biotechnology, Russian Federal State Agency for Health and Consumer Rights Surveillance, Koltsavo, Novosibirsk Oblast, 630559 Russia.
World-Class Genomic Research Center for Biological Safety and Technological Independence, Federal Scientific and Technical Program for the Development of Genetic Technologies, Vector State Research Center of Virology and Biotechnology, Russian Federal State Agency for Health and Consumer Rights Surveillance, Koltsovo, Novosibirsk Oblast, 630559 Russia.
Mol Biol (Mosk). 2021 Nov-Dec;55(6):987-998. doi: 10.31857/S0026898421060045.
The development of preventive vaccines became the first order task in the COVID-19 pandemic caused by SARS-CoV-2. This paper reports the construction of the pVAX-RBD plasmid containing the Receptor-Binding Domain (RBD) of the S protein and a unique signal sequence 176 which promotes target protein secretion into the extracellular space thereby increasing the efficiency of humoral immune response activation. A polyglucine-spermidine conjugate (PGS) was used to deliver pVAX-RBD into the cells. The comparative immunogenicity study of the naked pVAX-RBD and pVAX-RBD enclosed in the PGS envelope showed that the latter was more efficient in inducing an immune response in the immunized mice. In particular, RBD-specific antibody titers were shown in ELISA to be no higher than 1 : 1000 in the animals from the pVAX-RBD group and 1 : 42000, in the pVAX-RBD-PGS group. The pVAX-RBD-PGS construct effectively induced cellular immune response. Using ELISpot, it has been demonstrated that splenocytes obtained from the immunized animals effectively produced INF-y in response to stimulation with the S protein-derived peptide pool. The results suggest that the polyglucine-spermidine conjugate-enveloped pVAX-RBD construct may be considered as a promising DNA vaccine against COVID-19.
预防性疫苗的研发成为由严重急性呼吸综合征冠状病毒2（SARS-CoV-2）引发的新冠疫情中的首要任务。本文报道了含有S蛋白受体结合域（RBD）和独特信号序列176的pVAX-RBD质粒的构建，该信号序列可促进靶蛋白分泌到细胞外空间，从而提高体液免疫反应激活效率。使用聚甘氨酸-亚精胺缀合物（PGS）将pVAX-RBD递送至细胞内。对裸露的pVAX-RBD和包裹在PGS包膜中的pVAX-RBD进行的比较免疫原性研究表明，后者在免疫小鼠中诱导免疫反应更有效。具体而言，酶联免疫吸附测定（ELISA）显示，pVAX-RBD组动物的RBD特异性抗体效价不高于1:1000，而pVAX-RBD-PGS组为1:42000。pVAX-RBD-PGS构建体有效诱导了细胞免疫反应。使用酶联免疫斑点法（ELISpot）已证明，从免疫动物获得的脾细胞在用S蛋白衍生肽库刺激后能有效产生γ干扰素（INF-γ）。结果表明，聚甘氨酸-亚精胺缀合物包裹的pVAX-RBD构建体可被视为一种有前景的抗新冠DNA疫苗。
