Nanoparticle Vaccines Adopting Virus-like Features for Enhanced Immune Potentiation

Chattopadhyay, Saborni; Chen, Jui-Yi; Chen, Hui-Wen; Hu, Che-Ming Jack

Synthetic nanoparticles have high surface energies owing to their large radii of curvature. As a result, adsorption of protein can occur spontaneously owing to a combination of weak interaction forces, leading to the formation of protein corona formation [108] . This phenomenon was demonstrated to facilitate the assembly of synthetic virus-like nanoparticles [155] . Upon mixing gold nanoparticles with viral antigens, rapid protein adsorption took place on the nanoparticle surface. This adsorption led to colloidal stabilization of gold nanoparticles, preventing their aggregation in biological buffers. Biochemical analysis showed the facile assembly method surrounded each nanoparticle with approximately 900 coronavirus spike proteins, inducing enhanced anti-viral immune responses. The adsorption approach has been used extensively to associated antigens with nanocarriers, including nanoparticles made of gold [210] , calcium phosphate [211, 212] , aluminium hydroxide [213] , carbon [214, 215] , silica [117, 216] , and organic polymers [217, 218] . The range of adsorbed biomolecules vary from DNA [217, 219, 220] , adjuvant [221] , small peptides, and protein antigens [155, 218, 222, 223] . It is important to note that formation of protein corona is a dynamic process that can be strongly influenced by both nanomaterials and antigen of interest [224] . Studies have also shown that antigens can undergo conformational changes upon nanoparticle adsorption [225] , which could have both positive and negative effects on the resulting vaccine formulations.