The recombinant multi-epitope vaccine called VBP3 is designed to suppress tumor growth and angiogenesis through targeting both basic fibroblast growth factor (bFGF) and vascular endothelial growth factor A (VEGFA). We are aiming to produce VBP3 vaccine in a large scale and provide sufficient protein for pre-clinical study. High cost and potential toxicity are severe limitations of IPTG and we investigated whether lactose can mediate VBP3 induction. Firstly, we identified the biological characteristics and established a culture bank of VBP3 strains. The best-performing strains were selected and the fermentation mode of medium, bacterial growth and protein expression were optimized in shake flasks. We scaled up the VBP3 production in 10 L bioreactor using lactose as inducer and the protein yield was comparable with IPTG induction. Next, the target protein was purified by nickel-nitrilotriacetic acid (Ni-NTA) affinity chromatography, with a SDS-PAGE purity over 90%. Further, the purified VBP3 vaccine was subcutaneously injected in BALB/c mice and elicited high-titer anti-bFGF (1:32,000) and anti-VEGFA (1:4000) antibodies. Take together, lactose was an applicable inducer for VBP3 production and the eligible product of VBP3 was harvested in the large-scale fermentation, supporting the industrial production and pre-clinical study in the future. The VBP3 vaccine with superior immunogenicity might be used as a potential therapeutic vaccine for tumor treatment.

中文翻译：

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重组肿瘤多表位疫苗VBP3的发酵，纯化和免疫原性。

重组多表位疫苗称为VBP3，旨在通过靶向碱性成纤维细胞生长因子（bFGF）和血管内皮生长因子A（VEGFA）来抑制肿瘤生长和血管生成。我们的目标是大规模生产VBP3疫苗，并为临床前研究提供足够的蛋白质。高成本和潜在毒性是IPTG的严重局限性，我们研究了乳糖是否可以介导VBP3诱导。首先，我们鉴定了生物学特性并建立了VBP3菌株的培养库。选择性能最佳的菌株，并在摇瓶中优化培养基，细菌生长和蛋白质表达的发酵模式。我们使用乳糖作为诱导剂，在10 L生物反应器中扩大了VBP3的产量，蛋白质产量与IPTG诱导相当。下一个，目标蛋白通过亚硝酸三乙酸镍（Ni-NTA）亲和层析纯化，SDS-PAGE纯度超过90％。此外，将纯化的VBP3疫苗皮下注射到BALB / c小鼠中，并引发高滴度的抗bFGF（1：32,000）和抗VEGFA（1：4000）抗体。两者合计，乳糖是VBP3生产的适用诱导剂，并且在大规模发酵中收获了合格的VBP3产品，为将来的工业生产和临床前研究提供了支持。具有优越的免疫原性的VBP3疫苗可以用作潜在的用于肿瘤治疗的治疗性疫苗。将纯化的VBP3疫苗皮下注射到BALB / c小鼠中，并诱导出高滴度的抗bFGF（1：32,000）和抗VEGFA（1：4000）抗体。两者合计，乳糖是VBP3生产的适用诱导剂，并且在大规模发酵中收获了合格的VBP3产品，为将来的工业生产和临床前研究提供了支持。具有优越的免疫原性的VBP3疫苗可以用作潜在的用于肿瘤治疗的治疗性疫苗。将纯化的VBP3疫苗皮下注射到BALB / c小鼠中，并诱导出高滴度的抗bFGF（1：32,000）和抗VEGFA（1：4000）抗体。两者合计，乳糖是VBP3生产的适用诱导剂，并且在大规模发酵中收获了合格的VBP3产品，为将来的工业生产和临床前研究提供了支持。具有优越的免疫原性的VBP3疫苗可以用作潜在的用于肿瘤治疗的治疗性疫苗。