Overcoming Symmetry Mismatch in Vaccine Nanoassembly via Spontaneous Amidation.
Howarth M., Rahikainen R., Rijal P., Tan T., Draper S., Townsend A., Wu H-J., Bowden T., Andersson A-M., Barrett J.
Matching of symmetry at interfaces is a fundamental obstacle in molecular assembly. Virus-like particles (VLPs) are important platforms to generate vaccines against pathogenic threats including Covid-19. However, symmetry mismatch between multimeric antigens and VLP subunits can prohibit vaccine nanoassembly. Here we explore spontaneous amidation to establish principles for coupling VLPs to diverse antigen symmetries. SpyTag003/SpyCatcher003-mediated decoration enabled efficient VLP conjugation and extreme thermal resilience. Many people showed pre-existing antibodies to SpyTag:SpyCatcher, but decreased antibodies against 003 variants. We coupled efficiently to the computationally-designed VLP, built from twenty trimers, not only monomers (SARS-CoV-2) but also cyclic dimers (Newcastle Disease Virus or Lyme disease), trimers (Influenza Hemagglutinins), and tetramers (Influenza Neuraminidases). Even small antigens with dihedral symmetry could be displayed. For the global challenge of Influenza, Spy-display enabled powerful induction of neutralizing antibodies to trimeric and tetrameric antigens. SpyCatcher003 conjugation is compatible with nanodisplay of diverse symmetries, towards generation of potent vaccines.