Stabilized Pre-fusion RSV F Polypeptides for Vaccine Immunogenicity
Solution Overview
Problem
Current vaccine candidates based on the RSV F protein have failed due to stability, purity, and reproducibility issues, as they struggle to maintain the pre-fusion conformation necessary for effective immunogenicity, leading to ineffective natural immunity and a lack of a stable vaccine against respiratory syncytial virus (RSV) infection.
Innovation Solution
Development of stable, recombinant pre-fusion RSV F polypeptides that are stabilized in the pre-fusion conformation, comprising specific epitopes recognized by pre-fusion-specific monoclonal antibodies, and are produced using nucleic acid molecules and vectors to induce a neutralizing immune response.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If vaccine candidates based on RSV F protein are developed, then immunogenicity is improved, but stability deteriorates due to conformational changes from pre-fusion to post-fusion state
Solution Approach 1:
The patent applies preliminary action by introducing stabilizing mutations (such as N67I, S215P, and others in the HRB region) into the RSV F protein sequence before the conformational change can occur. These mutations are designed to lock the protein in its pre-fusion conformation, preventing the transition to post-fusion state that would otherwise occur naturally. This preemptive stabilization ensures the protein maintains its immunogenic pre-fusion structure throughout storage and administration.
Solution Approach 2:
The patent employs parameter changes by modifying specific amino acid residues in the RSV F protein sequence to alter its conformational stability parameters. The stabilizing mutations change the energy landscape of the protein, creating a deeper energy well for the pre-fusion state. This parameter modification allows the protein to maintain its desired conformation under various storage conditions while preserving its ability to elicit neutralizing antibodies.
2Reliability
If pre-fusion conformation is maintained for vaccine efficacy, then neutralizing antibody induction is improved, but manufacturing reproducibility deteriorates
Solution Approach 1:
The patent applies preliminary action by pre-engineering stabilizing mutations into the RSV F protein sequence during the design phase. These mutations (including multiple substitutions in the HRB region such as N67I, S215P, and others) are introduced before manufacturing to ensure the protein inherently maintains its pre-fusion conformation. This preliminary stabilization eliminates the need for complex post-production conformational control measures, thereby improving manufacturing reproducibility while preserving neutralizing antibody induction capability.
Solution Approach 2:
The patent employs parameter changes by modifying the amino acid sequence parameters of RSV F protein to create a more stable pre-fusion conformation. The stabilizing mutations alter the thermodynamic and kinetic parameters of the protein folding landscape, making the pre-fusion state the dominant conformer under manufacturing and storage conditions. This parameter optimization ensures consistent production of immunogenic protein across different batches and manufacturing runs.
3Reliability
If RSV F protein is used as vaccine candidate, then protective immunity is improved, but purity deteriorates due to conformational heterogeneity
Solution Approach 1:
The patent applies preliminary action by introducing stabilizing mutations into the RSV F protein sequence before expression and purification. These mutations (such as N67I, S215P, and other substitutions in the HRB region) are designed to lock the protein in its pre-fusion conformation, preventing conformational heterogeneity that would otherwise arise during production. This preliminary conformational locking ensures that the expressed protein population is homogeneous, facilitating easier purification and ensuring high purity of the final vaccine product while maintaining protective immunity.
4Reliability
If pre-fusion RSV F polypeptide is stabilized, then vaccine potency is improved, but device complexity deteriorates due to molecular engineering requirements
Solution Approach 1:
The patent applies preliminary action by pre-designing and pre-introducing stabilizing mutations into the RSV F protein sequence during the molecular engineering phase. The stabilizing mutations (including multiple amino acid substitutions in the HRB region) are incorporated into the gene sequence before expression system setup and protein production. This preliminary engineering approach consolidates the complexity into the initial design stage, resulting in a simplified production process that yields stable, potent vaccine without requiring complex post-production conformational control measures.
Data Source
AI summary
This disclosure provides stable pre-fusion respiratory syncytial virus (RSV) F polypeptides, immunogenic compositions comprising the polypeptides, and uses thereof for the prevention and/or treatment of RSV infection.