RSV-B Recombinant F Protein Stabilization in Pre-Fusion Form
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current RSV vaccines face challenges in maintaining the pre-fusion conformation of the F protein, which is critical for effective neutralization by antibodies, leading to instability and inefficacy in preventing RSV infections.
Innovation Solution
A recombinant RSV-B F protein with specific proline mutations in the F1 and F2 peptide fragments, stabilized by a linking bridge, is expressed to maintain the pre-fusion conformation, enhancing immunogenicity and stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If the natural RSV-B virus F protein antigen is recombinantly expressed in vitro, then the pre-fusion conformation is obtained, but the pre-fusion conformation is unstable and transforms into post-fusion conformation
Solution Approach 1:
The patent applies parameter changes by introducing specific amino acid mutations (proline substitutions at positions 65, 73, 138, 139, 141, 214, 215, 216, 279, and 377) to stabilize the pre-fusion conformation of the F protein. These mutations alter the structural parameters of the protein to maintain the metastable pre-fusion state, preventing spontaneous transformation to the post-fusion conformation while preserving immunogenicity.
Solution Approach 2:
The patent uses a linking bridge (comprising amino acids 23-25 or 23-27 of the F0 protein) as an intermediary element to connect the F1 and F2 subunits. This linking bridge acts as a structural mediator that locks the F protein in the pre-fusion conformation, preventing the conformational change to post-fusion state while maintaining the functional integrity of the antigen.
2Reliability
If the F protein is stabilized in pre-fusion conformation through mutations, then immunogenicity is enhanced, but the protein structure becomes more complex
Solution Approach 1:
The patent segments the F protein into distinct functional domains: the F1 subunit (amino acids 137-574), the F2 subunit (amino acids 26-109), and the linking bridge (amino acids 23-25 or 23-27). This segmentation allows for targeted mutations in specific regions to stabilize the pre-fusion conformation without unnecessarily complicating the entire protein structure, enabling precise control over immunogenicity while managing structural complexity.
Data Source
AI summary
The present application relates to a respiratory syncytial virus subtype B (RSV-B) recombinant F protein, a polynucleotide encoding the RSV-B recombinant F protein, a nucleic acid construct comprising the polynucleotide, an expression vector comprising the nucleic acid construct, a host cell into which the polynucleotide, the nucleic acid construct, or the expression vector is transformed or transfected, a stabilized trimer formed from the RSV-B recombinant F protein, an immunogenic composition comprising any of the foregoing, and use of any of the forgoing in the preparation of a vaccine for the prevention and/or treatment of respiratory syncytial virus infections. The RSV-B recombinant F protein comprises at least one epitope specific to the pre-fusion F protein, and can form a stable, pre-fusion conformation of F protein trimer. Furthermore, the RSV-B recombinant F protein can be expressed stably in a uniform form and with a significantly increased yield.