Stabilized RSV F Protein Trimer Prefusion Conformation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current RSV vaccines lack effectiveness due to the instability of the prefusion RSV F protein, which is crucial for eliciting a neutralizing immune response.
Innovation Solution
A recombinant RSV F trimer is developed, comprising three recombinant RSV F peptides with specific amino acid substitutions and deletions, along with a linker and a foldon sequence, to stabilize the prefusion conformation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If the RSV F protein is used in its native form, then it can elicit some immune response, but it is unstable and predominantly adopts a postfusion conformation that is less immunogenic
Solution Approach 1:
The patent applies parameter changes by introducing specific amino acid substitutions (155C, 290C, 190F, 207L) that alter the molecular parameters of the F protein. These substitutions stabilize the prefusion conformation through disulfide bond formation and cavity filling, shifting the conformational equilibrium without destroying the immunogenic epitopes. This resolves the contradiction by changing the stability parameter while preserving immunogenicity.
Solution Approach 2:
The patent creates a composite structure by combining the RSV F protein with stabilizing amino acid modifications. The engineered F protein incorporates both the native immunogenic regions and the introduced stabilizing elements (disulfide bonds, hydrophobic interactions), forming a composite molecular structure that simultaneously achieves conformational stability and immunogenicity.
2Stability of the object's composition
If the RSV F protein is stabilized in prefusion conformation using DS-Cav1 substitutions, then conformational stability is improved, but further stabilization is needed to prevent degradation during storage and transport
Solution Approach 1:
The patent further applies parameter changes by introducing additional amino acid substitutions (486C, 490C, 180C, 186C, 512C, 513C, 505C) that enhance the stability parameters of the F protein. These substitutions create additional disulfide bonds and strengthen hydrophobic interactions, increasing the energy barrier for conformational transition and proteolytic degradation, thereby extending storage stability.
Solution Approach 2:
The patent applies beforehand cushioning by pre-installing multiple stabilizing amino acid substitutions into the F protein sequence before storage or vaccination. These substitutions act as protective elements that preemptively prevent conformational degradation and proteolytic cleavage during storage and transport, cushioning the protein against destabilizing environmental conditions.
3Stability of the object's composition
If the F protein is cleaved into F1 and F2 subunits by furin, then the prefusion conformation is achieved, but the cleavage also leads to loss of the stabilization sequence and reduced stability
Solution Approach 1:
The patent applies segmentation by dividing the F protein into distinct functional domains with specific stabilizing modifications in each region. The N-terminal domain contains the 155C/290C disulfide bonds, the central domain has the 190F/207L cavity fillers, and the C-terminal domain includes additional stabilizing substitutions. This segmented approach to stabilization allows each domain to contribute independently to overall stability while managing structural complexity.
Solution Approach 2:
The patent uses stabilizing amino acid substitutions as intermediary elements that mediate between the furin cleavage event and the final stable prefusion conformation. These intermediary substitutions (particularly 155C/290C disulfide bonds) act as molecular anchors that lock the F1 and F2 subunits into a stable prefusion configuration after cleavage, preventing further degradation while maintaining the necessary structural complexity.
Data Source
AI summary
The disclosure relates to stable RSV F proteins and immunogenic compositions containing the same, as well as methods of using the immunogenic compositions and compositions comprising the RSV F proteins.