Nemati Afshin Samimi, Mirzaie Sako, Masoumian Mohammad Reza, Sheikhi Fatemeh, Jamalan Mostafa
Department of Biochemistry, Abadan University of Medical Sciences, Abadan, Iran.
Advanced Pharmaceutics and Drug Delivery Laboratory, Leslie L. Dan Faculty of Pharmacy, University of Toronto, Toronto, Canada.
Turk J Biol. 2022 Jun 23;46(4):263-276. doi: 10.55730/1300-0152.2615. eCollection 2022.
Human SARS coronavirus 2 (SARS-CoV-2) causes the current global COVID-19 pandemic. The production of an efficient vaccine against COVID-19 is under heavy investigation. In this study, we have designed a novel multiepitope DNA vaccine against SARS-CoV-2 using reverse vaccinology and DNA vaccine approaches. Applying these strategies led to reduce the time and costs of vaccine development and also improve the immune protective characteristics of the vaccine. For this purpose, epitopes of nucleocapsid, membrane glycoprotein, and ORF8 proteins of SARS-CoV-2 chose as targets for B and T-cell receptors. Accordingly, DNA sequences of selected epitopes have optimized for protein expression in the eukaryotic system. To this end, the Kozak and tissue plasminogen activator sequences were added into the epitope sequences for proper protein expression and secretion, respectively. Furthermore, interleukin-2 and beta-defensin 1 preproprotein sequences were incorporated to the designed DNA vaccine as an adjuvant. Modeling and refinement of fused protein composed of SARS-CoV-2 multiepitope antigens (fuspMA) have performed based on homology modeling of orthologous peptides, then constructed 3D model of fuspMA was more investigated during 50 ns of molecular dynamics simulation. Further bioinformatics predictions demonstrated that fuspMA is a stable protein with acceptable antigenic features and no allergenicity or toxicity characteristics. Finally, the affinity of fuspMA to the MHC I and II and TLRs molecules validated by the molecular docking procedure. In conclusion, it seems the designed multiepitope DNA vaccine could have a chance to be introduced as an efficient vaccine against COVID-19 after more in vivo evaluations.
人类严重急性呼吸综合征冠状病毒2（SARS-CoV-2）引发了当前的全球新型冠状病毒肺炎（COVID-19）大流行。针对COVID-19的高效疫苗的研发正在深入研究中。在本研究中，我们采用反向疫苗学和DNA疫苗方法设计了一种新型的针对SARS-CoV-2的多表位DNA疫苗。应用这些策略可减少疫苗研发的时间和成本，并提高疫苗的免疫保护特性。为此，选择SARS-CoV-2的核衣壳、膜糖蛋白和ORF8蛋白的表位作为B细胞和T细胞受体的靶点。相应地，所选表位的DNA序列已针对真核系统中的蛋白质表达进行了优化。为此，分别将Kozak序列和组织型纤溶酶原激活剂序列添加到表位序列中，以实现蛋白质的正确表达和分泌。此外，白细胞介素-2和β-防御素1前原蛋白序列作为佐剂被纳入设计的DNA疫苗中。基于直系同源肽的同源建模对由SARS-CoV-2多表位抗原（fuspMA）组成的融合蛋白进行了建模和优化，然后在50纳秒的分子动力学模拟过程中对构建的fuspMA三维模型进行了更深入的研究。进一步的生物信息学预测表明，fuspMA是一种稳定的蛋白质，具有可接受的抗原特性，且无致敏性或毒性特征。最后，通过分子对接程序验证了fuspMA与MHC I和II以及TLRs分子的亲和力。总之，经过更多的体内评估后，似乎所设计的多表位DNA疫苗有机会被作为一种针对COVID-19的高效疫苗推出。
