Self-assembling protein nanoparticles and virus like particles correctly display β-barrel from meningococcal factor H-binding protein through genetic fusion

Abstract

Recombinant protein-based vaccines are a valid and safer alternative to traditional vaccines based on live-attenuated or killed pathogens. However, the immune response of subunit vaccines is generally lower compared to that elicited by traditional vaccines and usually requires the use of adjuvants. The use of self-assembling protein nanoparticles, as a platform for vaccine antigen presentation, is emerging as a promising approach to enhance the production of protective and functional antibodies. In this work we demonstrated the successful repetitive antigen display of the C-terminal β-barrel domain of factor H binding protein, derived from serogroup B Meningococcus on the surface of different self-assembling nanoparticles using genetic fusion. Six nanoparticle scaffolds were tested, including viruslike particles with different sizes, geometries, and physicochemical properties. Combining computational and structure-based rational design we were able generate antigen-fused scaffolds that closely aligned with three-dimensional structure predictions. The chimeric nanoparticles were produced as recombinant proteins in Escherichia coli and evaluated for solubility, stability, self-assembly, and antigen accessibility using a variety of biophysical methods. Several scaffolds were identified as being suitable for genetic fusion with the βbarrel from fHbp, including ferritin, a de novo designed aldolase from Thermotoga maritima, encapsulin, CP3 phage coat protein, and the Hepatitis B core antigen. In conclusion, a systematic screening of self-assembling nanoparticles has been applied for the repetitive surface display of a vaccine antigen. This work demonstrates the capacity of rational structurebased design to develop new chimeric nanoparticles and describes a strategy that can be utilized to discover new nanoparticle-based approaches in the search for vaccines against bacterial pathogens.

Proof of concept for a single-dose Group B Streptococcus vaccine based on capsular polysaccharide conjugated to Qβ virus-like particles

“…The genes encoding for ferritin, mI3 and Qβ were synthesized as DNA strings by GeneArt (Thermo Fisher Scientific) optimizing the codon usage for expression in the E. coli . The genes were cloned into pET15b+TEV and pET21b+ (Merck-Sigma) PCR-amplified vectors using the Infusion cloning kit (Takara) following manufacturer instructions 33 , 63 . The plasmid pET24b+ encoding the Qβhp coat protein was purchased by GeneArt (Thermo Fisher Scientific).…”

A perspective on SARS-CoV-2 virus-like particles vaccines

“…The structure of VLPs is closely related to their efficiency in inducing immune responses in the organism. Studies have shown that the interaction of VLPs with the immune system is mainly related to two factors, VLPs size and their surface geometry [59] . VLPs of appropriate size (20-200 nm) can be drained to lymph nodes through lymphatic vessels.…”

Impact of Protein Nanoparticle Shape on the Immunogenicity of Antimicrobial Glycoconjugate Vaccines

“…In addition to their use as antigens, protein nanoparticles can also serve as carriers, addressing key challenges in vaccine design. They can carry various biomolecules, including polysaccharides [24,25], viral [26][27][28][29] and bacterial [30][31][32][33] protein antigens, peptides [34][35][36] and glycopeptides [37], nucleic acids [38] and small molecules [39,40] making them versatile platforms for vaccine development. Protein-based nanocarriers have displayed great potential for coronavirus vaccine research [41][42][43], indicating their relevance in addressing current global health challenges.…”