新型冠状病毒亚单位疫苗研制及其高效免疫增强剂的筛选

旨为推动新型冠状病毒（2019-nCoV）亚单位疫苗的开发并探索筛选适用于该疫苗的高效免疫增强剂，本试验分别诱导表达2019-nCoV- S和2019-nCoV- N两个蛋白，经纯化后测定目的蛋白含量，并分别加入不同浓度的松花粉多糖（PPPS）（200、400、800 mg/mL）作为佐剂制备基因工程亚单位疫苗，黄芪多糖佐剂作为对照。选取100只SPF级BALB/c小鼠随机分为10组，每种亚单位疫苗使用5组，免疫疫苗后检测各组小鼠免疫指标，探讨PPPS对2019-nCoV- S和2019-nCoV- N两种亚单位疫苗的免疫增强效果。结果显示，重组表达并纯化的目的蛋白分别在55.68 kD和45.64 kD处出现单一条带，经鉴定表达正确，蛋白质量浓度分别为1.12 mg/mL和0.66 mg/mL。用制作成的含佐剂亚单位疫苗免疫小鼠后发现400 mg/mL PPPS对两种疫苗的免疫效果均有显著的提升效果，并且效果优于黄芪多糖佐剂。综上所述，两种重组蛋白均能诱导较高的抗体水平，PPPS可以作为2019-nCoV亚单位疫苗的候选佐剂。

Novel Coronavirus Subunit Vaccine and Screening of Its Efficient Immune Enhancer

This work aims to promote the development of novel coronavirus（2019-nCoV）subunit vaccine and explore the screening of high-efficiency immune enhancers suitable for the vaccine. We induced the expressions of 2019-nCoV-S and 2019-nCoV-N proteins respectively, determined the contents of the target protein after purification, different concentrations of pine pollen polysaccharide（PPPS）（200, 400, 800 mg/mL）were added as adjuvants to prepare genetic engineering subunit vaccine, and astragalus polysaccharide adjuvant was used as control. One hundred SPF BALB/c mice were randomly divided into ten groups and each subunit vaccine was used in five groups. After immunization, the immune indexes of mice in each group were detected to explore the immune enhancement effect of PPPS on 2019-nCoV-S and 2019-nCoV-N subunit vaccines. The results showed that the recombinant expression and purification of the target protein showed a single band at 55.68 and 45.64 kD, respectively, and the expression was correct. The protein concentration was 1.12 and 0.66 mg/mL, respectively. After immunizing mice with the adjuvant subunit vaccine, it was found that 400 mg/mL PPPS significantly improve the immune effect of the two vaccines, and the effect was better than that of astragalus polysaccharide adjuvant. In summary, the two recombinant proteins can induce higher antibody levels, and PPPS can be used as a candidate adjuvant for 2019-nCoV subunit vaccine.