Construction of a large phage display antibody library by in vitro package and in vivo recombination

Capacity and diversity are extremely important to the quality of various phage display libraries. In this work, λ phage-based in vitro package was applied to construct a filamentous phage display antibody library so as to enlarge its capacity and introduce more sequence diversity in the final library. In vivo recombination via Cre recombinase/lox sites was also exploited to create V_H/V_L combination diversity based on multivalent package of λ phage packaging extracts on phagemid DNA concatemers. The library constructed with 10 μg concatenated phagemid DNA and ten vials of λ phage packaging extracts was calculated to contain 1.40×10¹⁰ independent clones. Higher capacity can be easily achieved when more materials are consumed. This strategy is somewhat more efficient than prior methods.