背景:一种具有成本效益的大肠杆菌表达系统已广泛用于生产病毒样颗粒(VLP)疫苗。然而,挑战在于平衡内毒素残留和去除成本,因为残留的内毒素会引起体内的炎症反应。
结果:在这项研究中,猪细小病毒病毒样颗粒(PPV-VLP)成功地从降低内毒素的BL21(BL21-DeE)组装,以及BL21脂质A的结构变化对内毒素活性的影响,免疫原性,并对安全性进行了调查。在RAW264.7细胞和BALB/c小鼠中,从BL21-DeE纯化的脂多糖产生的IL-6和TNF-α低于野生型BL21(BL21-W)。此外,与用BL21-W的VLP(BL21-W-VLP)和去除内毒素的VLP(ReE-VLP)免疫的小鼠相比,用PPV-VLP衍生的BL21-DeE(BL21-DeE-VLP)免疫的小鼠在3小时内显示出显着降低的炎症因子产生和较小的体温升高。此外,BL21-DeE-VLP免疫组的小鼠血清抗体水平与BL21-W-VLP组相似,但明显高于ReE-VLP组。此外,肝脏,肺,与BL21-W-VLP组相比,肾脏无病理损害。
结论:总体而言,这项研究提出了一种生产具有高免疫原性和最小内毒素活性的VLP的方法,而无需化学或物理去除内毒素的方法。该方法可以解决VLP中内毒素残留的问题并提供生产益处。
BACKGROUND: A cost-effective Escherichia coli expression system has gained popularity for producing virus-like particle (VLP) vaccines. However, the challenge lies in balancing the endotoxin residue and removal costs, as residual endotoxins can cause inflammatory reactions in the body.
RESULTS: In this study, porcine parvovirus virus-like particles (PPV-VLPs) were successfully assembled from Decreased Endotoxic BL21 (BL21-DeE), and the effect of structural changes in the lipid A of BL21 on endotoxin activity, immunogenicity, and safety was investigated. The lipopolysaccharide purified from BL21-DeE produced lower IL-6 and TNF-α than that from wild-type BL21 (BL21-W) in both RAW264.7 cells and BALB/c mice. Additionally, mice immunized with PPV-VLP derived form BL21-DeE (BL21-DeE-VLP) showed significantly lower production of inflammatory factors and a smaller increase in body temperature within 3 h than those immunized with VLP from BL21-W (BL21-W-VLP) and endotoxin-removed VLP (ReE-VLP). Moreover, mice in the BL21-DeE-VLP immunized group had similar levels of serum antibodies as those in the BL21-W-VLP group but significantly higher levels than those in the ReE-VLP group. Furthermore, the liver, lungs, and kidneys showed no pathological damage compared with the BL21-W-VLP group.
CONCLUSIONS: Overall, this study proposes a method for producing VLP with high immunogenicity and minimal endotoxin activity without chemical or physical endotoxin removal methods. This method could address the issue of endotoxin residues in the VLP and provide production benefits.