Fully synthetic human combinatorial antibody libraries (HuCAL) based on modular consensus frameworks and CDRs...

Area of Science:

• Immunology
• Molecular Biology
• Biotechnology

Background:

• The human antibody repertoire exhibits significant diversity, primarily derived from a limited set of germline gene families.
• Understanding the structural and sequence diversity of antibodies is crucial for developing therapeutic and diagnostic tools.

Purpose of the Study:

• To engineer synthetic antibody genes based on major human germline families for efficient library construction.
• To create modular antibody genes with accessible complementarity determining regions (CDRs) for diversification.
• To develop a platform for generating high-affinity antibody binders through phage display.

Main Methods:

• Analysis of human antibody repertoire to identify dominant V(H) and V(L) germline families.
• Design and synthesis of modular antibody genes optimized for expression in E. coli.
• Construction of antibody phage display libraries with diverse CDR regions.
• Molecular modeling to verify structural integrity and canonical classes.
• Selection experiments against various antigens to identify high-affinity binders.

Main Results:

• Seven V(H) and seven V(L) germline families account for over 95% of human antibody diversity.
• Synthetic genes were successfully designed with unique restriction sites flanking CDRs for modularity.
• Antibody phage display libraries of 2x10^9 members were generated with 61% correct sequences.
• Selection yielded diverse binders with high affinities, demonstrating the platform's efficacy.

Conclusions:

• A limited number of human germline gene families underpin antibody diversity.
• The developed modular synthetic gene platform facilitates rapid generation and optimization of antibody libraries.
• This approach enables efficient discovery of high-affinity antibody binders for various applications.