PCV2 virus-like particles as well as preparation method thereof and splitting and VLP assembly buffer liquor

Abstract

The invention discloses PCV2 virus-like particles as well as a preparation method thereof and splitting and VLP assembly buffer liquor. Based on an autonomous optimization design, a PCV2 nucleocapsid protein gene which is suitable for efficiently expressing in a prokaryotic expression system is artificially synthesized, a full-length gene sequence of the PCV2 nucleocapsid protein gene is expressed by an escherichia coli prokaryotic expression system, and the virus-like particles are efficiently and autonomously assembled by utilizing soluble nucleocapsid protein of the full-length gene sequence under a special condition. An innovation point of the invention is that PCV2VLPs are obtained by utilizing the prokaryotic expression system instead of adopting the conventional method for obtaining VLPs through an eukaryotic expression system; the method is low in cost, simple and efficient, and suitable for large-scale industrial application; moreover, an innovative buffer liquor formula integrating double functions, which not only can promote thallus splitting, but also can be suitable for self-assembling of VLPs, is also applied; besides, the PCV2 virus-like particles obtained in the invention are very highly similar with wild type virus in outline and good in immunogenicity, and can be applied to developing a subunit vaccine and a drug delivery carrier with utilization potentiality of porcine circovirus.

Description

technical field [0001] The invention belongs to the technical field of porcine circovirus vaccine research, and in particular relates to a method for preparing PCV2 virus-like particles, the virus-like particles prepared by the method, and a lysis and VLP assembly buffer used in the method. Background technique [0002] Porcine circovirus type 2 (porcine circovirus type 2, PCV2) belongs to the family Circoviridae, with a diameter of about 17nm, no envelope, icosahedral symmetry, covalently closed circular single-stranded DNA virus. PVC2 is the main pathogen that causes postweaning multisystemic wasting syndrome (PMWS) in piglets, and can also cause porcine dermatis and nephropathy syndrome (PDNS) and porcine respiratory syndrome (porcine respiratory syndrome) in fattening pigs. disease complex, PRDC), neonatal piglet diarrhea and other syndromes, as well as immunosuppression in pigs, it is difficult to carry out effective drug treatment. In addition, PVC2 is often concurrent...

AI Technical Summary

Problems solved by technology

However, compared with the VLPs produced by the prokaryotic expression system, the production process of using the insect-baculovirus system to express proteins is complicated and the price is high.

Many researchers have successfully expressed PCV2 Capsid protein in E. coli, but they cannot assemble it into VLPs in vitro

In 2013, Yin et al. fused the Sumo-tag to the 5' end of the PCV2Capsid gene, which could improve the expression and solubility of the PCV2Capsid protein in Escherichia coli, and the PCV2Capsid protein could be successfully assembled into VLPs in vitro, but because it was fused with the Sumo-tag Post-expression, the expressed and purified fusion protein needs to use protease to remove its tag, so that the target protein can be assembled into VLPs, which increases the difficulty and cost of production, and the concentration of VLPs is low, and the assembly efficiency is not high

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