分子排阻色谱(SEC)分离纯化口蹄疫病毒及其病毒样颗粒的比较

Isolation and purification of FMDV and FMDV-VLPs by size exclusion chromatography

口蹄疫(FMD)是一种世界范围内的烈性偶蹄动物传染病。传统口蹄疫灭活疫苗可以降低疾病发病率,是目前预防口蹄疫的重要手段之一,但灭活疫苗存在病毒逃逸等生物安全问题,已经不适应我国重大疫病逐步净化的方针政策。口蹄疫病毒样颗粒(virus-like particles,VLPs)仅由病毒结构蛋白组成,不含遗传物质,是一种与天然病毒形态最为接近的抗原,其免疫原性与天然病毒相似,被视为安全性更高的疫苗。因此,FMDV-VLPs疫苗的纯化尤为重要。本文通过分子排阻色谱(size exclusion chromatography,SEC)系统对大肠杆菌组装的FMDV-VLPs进行纯化条件摸索。以FMDV为对照,对纯化后的FMDV-VLPs进行表征,结果显示,大肠杆菌组装的FMDV-VLPs与对照样品出峰位置基本一致,且粒径均在20~30 nm,同时初步计算出大肠杆菌组装效率大概为31.4%。该纯化过程具有操作简单、易于放大并且能够检测粒子大小等优点,可以使FMDV-VLPs疫苗更适合产业化生产以及更接近临床应用。

Foot-and-mouth disease(FMD) is an important global disease of cloven-hoofed animals.The traditional inactivated-FMD vaccine can reduce the number of disease outbreaks in the world.It is an effectively control to prevent foot-and-mouth disease(FMDV).However,inactivated vaccines have some limitations,which the virus is incomplete inactivated or inadvertent escaped during manufacturing,and have not adapted to the principles and policies for the gradual purification of major diseases in China.Foot-and-mouth disease virus-like particles(VLPs) are empty particles composed of only viral structural proteins but not the genetic materials that mimic the overall structure of the native virions.VLPs can trigger potent immune responses,thus VLPs have advantages in terms of immunogenicity and safety over previous vaccines.Therefore,purification of the FMDV-VLPs vaccine is particularly important.In this paper,the conditions of purification of Escherichia coli assembled FMDV-VLPs were explored using size exclusion chromatography(SEC) system.The purified VLPs were characterized and compared with FMDV virion,the results showed that the FMDV-VLPs were basically consistent with the peak position of the control sample of FMDV,and the particle size was similar at 20-30 nm.At the same time,the FMDV-VLP assembly efficiency was estimated to be approximately 31.4%.This purification processes may benefit from easy operation,simple amplification and a more detailed picture of the virus size distribution,which is more suitable for large-scale industrial production and clinical use.