Isolation of Novel Fully Human Single-Domain Antibodies Targeting GUCY2C from a Heavy-Chain-Only Transgenic Mouse...

Area of Science:

• Immunology
• Biotechnology
• Oncology

Background:

• Traditional single-domain antibodies (sdAbs) are sourced from camelids and sharks, posing limitations due to species size and reproduction rates.
• Developing fully human sdAbs is crucial for reducing immunogenicity and enhancing therapeutic applications.

Purpose of the Study:

• To create fully human heavy-chain-only antibodies (HcAbs) targeting the guanylyl cyclase C (GC-C) tumor antigen.
• To evaluate the efficacy of a novel huNano mouse platform for rapid and efficient sdAb generation.

Main Methods:

• Immunization of fully huNano mice with GC-C recombinant protein.
• Selection of GC-C specific sdAbs using phage display technology.
• Characterization of antibody binding affinity, thermal stability, and purity via ELISA, FACS, BLI, and SEC-HPLC.

Main Results:

• Successfully generated multiple sdAbs with specific GC-C recognition and strong binding affinities.
• Achieved >95% monomeric purity and <5% aggregate content after one-step purification.
• Observed good thermal stability with melting temperatures (Tm) and aggregation onset temperatures (Tagg) between 60-68 °C.

Conclusions:

• The huNano mouse platform efficiently produces high-quality, fully human sdAbs.
• The developed GC-C targeting sdAbs are promising candidates for CAR-T therapy and bispecific antibody development.