Engineering sustainable squalene analogues for novel vaccine adjuvant emulsions

项目摘要 全球大流行流感疫苗生产能力不足以满足事件的预期需求 一场高度致命的流感大流行。目前的H5N1疫苗需要较高的抗原剂量(例如90μg)或 与角鲨烯类水包油乳剂联合使用，增强和扩大免疫原性 以及抗原剂量节约。角鲨烯是一种天然存在的低聚异戊二烯(即极低分子量 异戊二烯聚合物)从鲨鱼肝脏中提取，这是一种令人担忧的可持续性来源。此外，生物学上的 角鲨烯的作用机制尚不清楚，也没有系统的佐剂比较。 角鲨烯乳剂与基于类似低聚异戊二烯的乳剂的活性比较已在 文学。该提案明确了一项发展各种低聚异戊二烯可持续生产的计划 利用生物工程生物和合成聚合物化学合成角鲨烯的类似物。选定的结构将 然后在水包油乳状液中配制，并对其物理化学稳定性进行评价。重要的是，我们 建议通过使用角鲨烯和低聚异戊二烯类似物来确定结构-活性关系(SAR) 与H5N1流感抗原相结合的体外人类和活体小鼠模型。而且，有能力 通过化学修饰进一步增强佐剂活性，改善选定的佐剂的理化性质 将对低聚异戊二烯的结构进行评估。所产生的技术可能适用于许多其他疫苗 需要乳剂佐剂以节省抗原剂量或增强免疫反应的。

Project Summary Global pandemic influenza vaccine production capacity is insufficient to meet the expected demand in the event of a highly lethal influenza pandemic. Current H5N1 vaccines require high antigen doses (e.g. 90 μg) or are combined with squalene-based oil-in-water emulsion adjuvants for enhanced and broadened immunogenicity as well as antigen dose sparing. Squalene is a naturally occurring oligoisoprene (i.e. a very low molecular weight polymer of isoprene) derived from shark liver, a source with sustainability concerns. Moreover, the biological mechanisms of action of squalene are still not well understood and no systematic comparison of the adjuvant activity of squalene emulsions compared to emulsions based on analog oligoisoprenes has been reported in the literature. This proposal defines a program to develop the sustainable production of various oligoisoprene analogues of squalene using bioengineered organisms and synthetic polymer chemistry. Selected structures will then be formulated in oil-in-water emulsions and evaluated for physicochemical stability. Importantly, we propose to identify structure-activity relationships (SAR) by employing squalene and oligoisoprene analogues in in vitro human and in vivo mouse models in combination with an H5N1 influenza antigen. Moreover, the ability to further enhance adjuvant activity by chemical modification to improve physicochemical properties of selected oligoisoprene structures will be evaluated. The technology generated could be applicable to many other vaccines that have need of emulsion-based adjuvants for antigen dose sparing or enhanced immune responses.