Rijal Pramila, Wei Leiyan, Paesen Guido C, Stuart David I, Haworth Mark, Huang Kuan-Ying A, Bowden Thomas A, Townsend Alain R M
Chinese Academy of Medical Science Oxford Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom.
MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom.
Elife. 2025 Sep 9;14:RP105317. doi: 10.7554/eLife.105317.
Influenza virus neuraminidase (NA) is a crucial target for protective antibodies, yet the development of recombinant NA protein as a vaccine has been held back by instability and variable expression. We have taken a pragmatic approach to improving expression and stability of NA by grafting antigenic surface loops from low-expressing NA proteins onto the scaffold of high-expressing counterparts. The resulting hybrid proteins retained the antigenic properties of the loop donor while benefiting from the high-yield expression, stability, and tetrameric structure of the loop recipient. These hybrid proteins were recognised by a broad set of human monoclonal antibodies elicited by influenza infection or vaccination, with X-ray structures validating the accurate structural conformation of the grafted loops and the enzymatic cavity. Immunisation of mice with NA hybrids induced inhibitory antibodies to the loop donor and protected against lethal influenza challenge. This pragmatic technique offers a robust solution for improving the expression and stability of influenza NA proteins for vaccine development.
流感病毒神经氨酸酶（NA）是保护性抗体的关键靶点，然而，重组NA蛋白作为疫苗的开发一直受到稳定性和表达多变性的阻碍。我们采取了一种务实的方法，通过将低表达NA蛋白的抗原性表面环嫁接到高表达对应物的支架上来提高NA的表达和稳定性。所得的杂合蛋白保留了环供体的抗原特性，同时受益于环受体的高产量表达、稳定性和四聚体结构。这些杂合蛋白被流感感染或疫苗接种引发的多种人类单克隆抗体识别，X射线结构验证了嫁接环和酶腔的准确结构构象。用NA杂合体免疫小鼠可诱导针对环供体的抑制性抗体，并能抵御致命的流感攻击。这种务实的技术为提高用于疫苗开发的流感NA蛋白的表达和稳定性提供了一个可靠的解决方案。
