Antibody Libraries With Liability-Filtered CDR Diversity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing antibody libraries face challenges with non-functional members due to liabilities such as glycosylation sites, deamidation sites, unpaired cysteines, and aggregation, leading to poor expression and folding, especially in recombinant systems like E. coli, yeast, or mammalian cells.
Innovation Solution
Development of antibody libraries comprising heavy and light chain CDRs derived from naturally-occurring antibodies, excluding liabilities like glycosylation sites, deamidation sites, and unpaired cysteines, ensuring high functional diversity and improved expression and folding.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If synthetic antibody libraries are constructed with randomized CDR sequences, then genetic diversity and expression are improved, but many non-functional members are included due to liabilities affecting folding and stability
Solution Approach 1:
The patent applies preliminary action by pre-selecting framework regions with proven good folding and expression characteristics before introducing CDR diversity. This ensures that the scaffold is already optimized for functionality before the CDRs are randomized, thereby improving the proportion of functional members while maintaining genetic diversity.
Solution Approach 2:
The patent applies local quality by treating different regions of the antibody differently: framework regions are selected for optimal folding and expression properties, while CDR regions are randomized for diversity. This localized optimization ensures that each region contributes its specific function without compromising the other.
2Reliability
If natural antibody libraries are used with rearranged V genes, then a higher proportion of biologically functional members is achieved, but diversity is limited and expression in recombinant systems is poor
Solution Approach 1:
The patent merges the advantages of both synthetic and natural libraries by combining pre-selected framework regions (providing good folding and expression) with randomized CDR sequences (providing diversity). This hybrid approach creates a library that achieves both high functional proportion and extensive diversity.
Solution Approach 2:
The patent applies parameter changes by modifying the framework regions to have optimized properties for recombinant expression while maintaining the natural CDR sequences' diversity. This involves selecting frameworks with specific characteristics that enhance stability and expression without limiting CDR variation.
3Reliability
If CDRs from natural antibodies are used, then functional members are increased, but liabilities such as glycosylation sites, deamidation sites, and unpaired cysteines reduce expression and stability
Solution Approach 1:
The patent applies taking out by removing or excluding CDR sequences that contain liabilities such as glycosylation sites, deamidation sites, and unpaired cysteines from the library construction process. This extraction of harmful elements ensures that only CDRs with good developability characteristics are included, thereby improving expression and stability while maintaining functional diversity.
Solution Approach 2:
The patent converts the potential harm of natural CDR liabilities into a benefit by using bioinformatic analysis to identify and exclude problematic sequences. This process transforms what would be harmful natural diversity into a controlled set of CDRs that maintain natural functionality while eliminating expression-reducing liabilities.
4Ease of manufacture
If antibodies with optimized frameworks are selected, then expression and folding are improved, but the library excludes natural diversity due to formulaic generation within restricted scaffolds
Solution Approach 1:
The patent applies segmentation by separating the antibody into framework regions and CDR regions, optimizing each independently. The frameworks are selected for manufacturing ease, while the CDRs are randomized to capture natural diversity. This segmentation allows both optimized expression and extensive diversity to coexist.
Solution Approach 2:
The patent applies universality by using a small set of well-characterized framework regions that can serve multiple functions: providing structural stability, ensuring proper folding, and enabling high-level expression. These universal frameworks support a wide variety of CDR sequences, thereby achieving both manufacturing ease and diversity.
Data Source
AI summary
Antibody libraries comprising a plurality of heavy chain variable domains and/or a plurality of light chain variable domains, which comprise complementary determining regions (CDRs) found in naturally-occurring human antibodies, and methods of making such antibody libraries. The antibody libraries are free of members that comprise one or more liabilities affecting one or more features of such members. Further, the antibody libraries comprise members having heavy chain and/or light chain CDRs not found in the same naturally-occurring human antibody.