Self-assembling materials based on peptides have shown great potential as vaccine adjuvants. In our previous work, we have demonstrated that nanofibers based on D-peptide Nap-G^DF^DF^DY are good candidates for vaccine adjuvants. Here we further found that supramolecular hydrogels based on positively charged D-peptide Nap-G^DF^DF^DY^DK as vaccine adjuvants could induce stronger immune response. We designed and synthesized two D-peptide derivatives, one with a positive charge (Nap-G^DF^DF^DY^DK) and the other with a negative charge (Nap-G^DF^DF^DY^DE). Both of them could form the hydrogels constructed by nanofibers. The nanofibers formed by Nap-G^DF^DF^DY^DK promoted the more powerful immune response in mice against the antigen chicken egg albumin (OVA) than peptides Nap-G^DF^DF^DY and Nap-G^DF^DF^DY^DE. Through cell experiments, we demonstrated that the main reason was that nanofibers formed by Nap-G^DF^DF^DY^DK could enhance the uptake of OVA by primary antigen presenting cells. Most importantly, it was intriguing that the nanofibers based on Nap-G^DF^DF^DY^DK could evoke long-lasting antibody titers for 28 weeks at a single dose of protein vaccine. Our study demonstrated that supramolecular hydrogels based on positively charged D-peptide were promising vaccine adjuvants and might be very useful for antibody production and vaccine development.

中文翻译：

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含肽纳米纤维作为佐剂的单剂蛋白疫苗可引发持久的抗体滴度。

基于肽的自组装材料已显示出作为疫苗佐剂的巨大潜力。在我们以前的工作中，我们已经证明基于D肽Nap-G ^D F ^D F ^D Y的纳米纤维是疫苗佐剂的良好候选者。在这里，我们进一步发现基于带正电荷的D肽Nap-G ^D F ^D F ^D Y ^D K作为疫苗佐剂的超分子水凝胶可以诱导更强的免疫反应。我们设计并合成了两种D肽衍生物，一种带有正电荷（Nap-G ^D F ^D F ^D Y ^D K），另一种带有负电荷（Nap-G ^D F^D F ^D Y ^D E）。它们都可以形成由纳米纤维构成的水凝胶。与肽Nap-G ^D F ^D F ^D Y和Nap-G ^D F ^D相比，Nap-G ^D F ^D F ^D Y ^D K形成的纳米纤维促进了小鼠对抗原鸡卵白蛋白（OVA）的更强大的免疫反应。F ^D Y ^D E.通过细胞实验，我们证明了主要原因是由Nap-G ^D F ^D F ^D Y ^D形成的纳米纤维。钾可以增强原代抗原呈递细胞对OVA的吸收。最重要的是，令人惊奇的是，基于Nap-G ^D F ^D F ^D Y ^D K的纳米纤维可以在单剂蛋白疫苗中引起28星期的持久抗体效价。我们的研究表明，基于带正电荷的D肽的超分子水凝胶是很有希望的疫苗佐剂，可能对抗体生产和疫苗开发非常有用。