Development of a new genotype–phenotype linked antibody screening system

Antibodies are powerful tools for the therapy and diagnosis of various diseases. In addition to conventional hybridoma-based screening, recombinant antibody-based screening has become a common choice; however, its application is hampered by two factors: 1) screening starts only after Ig gene cloning and recombinant antibody production, and 2) the antibody is composed of paired chains, heavy and light, commonly expressed from two independent expression vectors. Here, we introduce a method for the rapid screening of recombinant monoclonal antibodies by establishing a Golden Gate-based dual-expression vector and in vivo expression of membrane-bound antibodies. Using this system, we demonstrated the efficient isolation of influenza cross-reactive antibodies with high affinity from mouse germinal center B cells over 4 days. This system is particularly useful for isolating therapeutic or diagnostic antibodies (e.g., during foreseen pandemics). Impact Statement A Golden Gate-based dual-expression vector enables rapid screening, facilitating efficient isolation of high-affinity cross-reactive antibodies for therapeutic or diagnostic use, offering a crucial advance for pandemic preparedness. ### Competing Interest Statement The authors have declared no competing interest.