Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK.
Jenner Institute, University of Oxford, Oxford, OX3 7DQ, UK.
Sci Rep. 2019 Mar 15;9(1):4625. doi: 10.1038/s41598-019-40985-w.
For many infectious diseases there is still no vaccine, even though potential protective antigens have been identified. Suitable platforms and conjugation routes are urgently needed to convert the promise of such antigens into broadly protective and scalable vaccines. Here we apply a newly established peptide-peptide ligation approach, SnoopLigase, for specific and irreversible coupling of antigens onto an oligomerization platform. SnoopLigase was engineered from a Streptococcus pneumoniae adhesin and enables isopeptide bond formation between two peptide tags: DogTag and SnoopTagJr. We expressed in bacteria DogTag linked to the self-assembling coiled-coil nanoparticle IMX313. This platform was stable over months at 37 °C when lyophilized, remaining reactive even after boiling. IMX-DogTag was efficiently coupled to two blood-stage malarial proteins (from PfEMP1 or CyRPA), with SnoopTagJr fused at the N- or C-terminus. We also showed SnoopLigase-mediated coupling of a telomerase peptide relevant to cancer immunotherapy. SnoopLigase-mediated nanoassembly enhanced the antibody response to both malaria antigens in a prime-boost model. Including or depleting SnoopLigase from the conjugate had little effect on the antibody response to the malarial antigens. SnoopLigase decoration represents a promising and accessible strategy for modular plug-and-display vaccine assembly, as well as providing opportunities for robust nanoconstruction in synthetic biology.
对于许多传染病，尽管已经确定了潜在的保护性抗原，但仍然没有疫苗。迫切需要合适的平台和缀合途径，将这些抗原转化为广泛保护和可扩展的疫苗。在这里，我们应用了一种新建立的肽-肽连接方法 SnoopLigase，用于将抗原特异性和不可逆地偶联到寡聚化平台上。SnoopLigase 是从肺炎链球菌黏附素工程改造而来的，能够在两个肽标签之间形成异肽键：DogTag 和 SnoopTagJr。我们在细菌中表达了与自组装卷曲螺旋纳米颗粒 IMX313 相连的 DogTag。当冻干时，该平台在 37°C 下可稳定数月，即使煮沸后仍保持反应性。IMX-DogTag 可以有效地与两种血阶段疟原蛋白（来自 PfEMP1 或 CyRPA）偶联，SnoopTagJr 融合在 N 或 C 末端。我们还展示了 SnoopLigase 介导的与与癌症免疫治疗相关的端粒酶肽的偶联。SnoopLigase 介导的纳米组装增强了对两种疟疾抗原的抗体反应，在初次-加强模型中均有体现。从缀合物中包含或耗尽 SnoopLigase 对疟原抗原的抗体反应几乎没有影响。SnoopLigase 修饰代表了一种有前途和可访问的模块化即插即用疫苗组装策略，以及为合成生物学中的稳健纳米构建提供了机会。
