MHC Molecule Screening via Cell-Free Refolding and Peptide Exchange
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for screening MHC binding peptides are labor-intensive, not scalable, and inefficient, particularly when dealing with large numbers of peptides, often resulting in high material losses and requiring complex cell-based assays.
Innovation Solution
A method involving the refolding or peptide exchange of MHC molecules in solution, followed by loading with putative binding peptides, and determining loading efficiency using conformational binding assays, allows for high-throughput screening of MHC binding peptides in a cell-free assay, enabling the production of functional MHC oligomers or pentamers for detecting T cell epitopes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If cell-based assays are used for screening MHC binding peptides, then binding affinity can be determined accurately, but the process becomes labor-intensive and not scalable
Solution Approach 1:
The patent replaces cell-based biological assays with a cell-free biochemical assay system. MHC molecules are expressed, purified, and used in vitro to screen peptide libraries. This substitution eliminates the need for live cell culture while maintaining the ability to measure peptide-MHC binding, thereby increasing throughput and scalability without sacrificing binding affinity determination accuracy.
Solution Approach 2:
The invention extracts the essential binding function from living cells by isolating and purifying MHC molecules. The MHC molecules are removed from their cellular context and used in purified form for screening assays. This extraction allows the binding assay to be performed in a simplified, cell-free system that is more scalable and less labor-intensive while preserving the specific peptide-MHC interaction of interest.
2Quantity of substance
If large numbers of peptides are screened using conventional methods, then comprehensive epitope identification is achieved, but material losses increase and efficiency decreases
Solution Approach 1:
The patent employs peptide libraries where multiple copies of each peptide sequence are synthesized. This allows comprehensive screening of large numbers of peptides using small amounts of unique peptide sequences. The copying approach enables statistical analysis of binding data while minimizing material consumption, as the same peptide sequence can be tested multiple times across different MHC alleles or replicates.
Solution Approach 2:
The invention performs preliminary purification and characterization of MHC molecules before the actual screening process. This preliminary action ensures that the MHC reagents are of high quality and consistent activity, reducing the need for repeated experiments and material waste. The method also includes preliminary optimization of assay conditions to maximize binding signal and minimize background, thereby improving efficiency when screening large peptide sets.
3Reliability
If complex cell-based assays are used, then T cell activation can be measured, but the device complexity and operational difficulty increase
Solution Approach 1:
The patent replaces complex cell-based T cell activation assays with a simpler cell-free binding assay. Instead of measuring T cell responses which require live cells, cytokine detection, and complex readout systems, the invention directly measures peptide-MHC binding using purified proteins and standard biochemical detection methods. This substitution maintains reliability for identifying epitopes while dramatically reducing assay complexity and operational difficulty.
4Measurement precision
If purified MHC molecules are produced for each peptide screen, then accurate binding data is obtained, but production time and cost increase
Solution Approach 1:
The patent performs preliminary expression and purification of MHC molecules in advance, creating stock solutions of purified MHC that can be used for multiple screening experiments. This preliminary action eliminates the need to produce and purify MHC molecules for each individual peptide screen, thereby maintaining binding data accuracy while significantly reducing production time and cost for subsequent screens.
Data Source
AI summary
The invention relates to a method for screening the binding properties of constituent peptides of MHC molecules by providing in solution MHC molecules or their constituent peptides for a set of MHC molecules including a plurality of subsets of MHC molecules, wherein the MHC molecules of each subset differ from MHC molecules of at least one other subset in at least one of the putative MHC binding peptide, an MHC alpha chain and an MHC beta chain, and loading said MHC molecules with an MHC binding peptide by (i) refolding of the MHC alpha chain and beta chain peptides in presence of said MHC binding peptide or (ii) by peptide exchange or loading with an unlabelled MHC binding peptide in the absence of any labelled MHC binding peptide, (b) taking of at least one sample from each subset, and (c) determining loading efficiency for the sample of step (b).