Synthetic rewriting of the IGH locus

Area of Science:

• Immunology
• Genomics
• Synthetic Biology

Background:

• V(D)J recombination is crucial for generating antibody diversity by joining V, D, and J gene segments.
• Existing V(D)J recombination processes have inherent constraints that limit the full spectrum of antibody diversity.

Purpose of the Study:

• To design and construct a synthetic human immunoglobulin heavy chain locus (SynIgh) with enhanced modularity and extensibility.
• To investigate the potential of SynIgh to overcome limitations in V(D)J recombination and expand antibody diversity.
• To establish a generalizable framework for engineering mammalian genome architecture.

Main Methods:

• De novo design and assembly of a synthetic immunoglobulin heavy chain locus (SynIgh) incorporating diverse V_H, D, and J_H genes and synthetic rearrangement sites.
• Synthesis of the SynIgh sequence with a stabilizer and generation of a SynIgh mouse model.
• Implementation of a dual-rearrangement strategy combining synthetic and natural V(D)J recombination in mice.

Main Results:

• Successful design, synthesis, and assembly of the SynIgh locus.
• Generation of a SynIgh mouse model capable of V(D)J recombination.
• Demonstration that the dual-rearrangement strategy shuffles the SynIgh locus, significantly expanding V(D)J recombination outcomes and antibody diversity.

Conclusions:

• The synthetic immunoglobulin heavy chain locus (SynIgh) provides a powerful platform for exploring and expanding antibody diversity.
• The dual-rearrangement strategy offers a novel approach to reconfigure antibody generation.
• SynIgh serves as a generalizable model for engineering mammalian genome architecture and function.