Guangdong Provincial Key Laboratory of Agro-Animal Genomics and Molecular Breeding & Subtropical Sericulture and Mulberry Resources Protection and Safety Engineering Research Center, College of Animal Science, South China Agricultural University, Guangzhou 510642, China.
Henan Provincial Engineering and Technology Center of Health Products for Livestock and Poultry, College of Life Science and Agricultural Engineering, Nanyang Normal University, Nanyang 473061, China.
Viruses. 2022 Jan 13;14(1):140. doi: 10.3390/v14010140.
The baculovirus display system (BDS), an excellent eukaryotic surface display technology that offers the advantages of safety, efficiency, and economy, is widely used in biomedicine. A previous study using rBacmid-Δgp64-ires-gp64 expressed in low copy numbers of the gene achieved high-efficiency expression and co-display of three fluorescent proteins (GFP, YFP, and mCherry). However, low expression of GP64 in recombinant baculoviruses also reduces the efficiency of recombinant baculovirus transduction into mammalian cells. In addition, the baculovirus promoter has no expression activity in mammalian cells and thus cannot meet the application requirements of baculoviral vectors for the BDS. Based on previous research, this study first determined the expression activity of promoters in insect 9 cells and mammalian cells and successfully screened the very early promoter to mediate the co-expression of multiple genes. Second, utilizing the envelope display effect of the INVASIN and VSVG proteins, the efficiency of transduction of recombinant baculovirus particles into non-host cells was significantly improved. Finally, based on the above improvement, a recombinant baculovirus vector displaying four antigen proteins with high efficiency was constructed. Compared with traditional BDSs, the rBacmid-Δgp64 system exhibited increased display efficiency of the target protein by approximately 3-fold and induced an approximately 4-fold increase in the titer of serum antibodies to target antigens in Bal B/c mice. This study systematically explored the application of a new multi-gene co-display technology applicable to multi-vaccine research, and the results provide a foundation for the development of novel BDS technologies.
杆状病毒展示系统（BDS）是一种出色的真核表面展示技术，具有安全性、高效性和经济性等优点，被广泛应用于生物医学领域。之前的研究利用低拷贝数的 rBacmid-Δgp64-ires-gp64 表达，实现了三种荧光蛋白（GFP、YFP 和 mCherry）的高效表达和共展示。然而，GP64 在重组杆状病毒中的低表达也降低了重组杆状病毒向哺乳动物细胞转导的效率。此外，杆状病毒启动子在哺乳动物细胞中没有表达活性，因此不能满足杆状病毒载体在 BDS 中的应用要求。基于之前的研究，本研究首先确定了启动子在昆虫 9 细胞和哺乳动物细胞中的表达活性，并成功筛选出了极早期启动子来介导多个基因的共表达。其次，利用 INVASIN 和 VSVG 蛋白的包膜展示效应，显著提高了重组杆状病毒颗粒向非宿主细胞的转导效率。最后，基于上述改进，构建了一个高效展示四个抗原蛋白的重组杆状病毒载体。与传统的 BDS 相比，rBacmid-Δgp64 系统使目标蛋白的展示效率提高了约 3 倍，并且在 Bal B/c 小鼠的血清抗体效价方面，使针对目标抗原的反应提高了约 4 倍。本研究系统地探索了一种新的多基因共展示技术在多疫苗研究中的应用，为新型 BDS 技术的发展提供了基础。
