Identification of antibodies targeting desired epitopes

To assess the feasibility of an antigen/antibody co-display system for epitope binning, a qAb library consisting of 14 single-chain fragments was displayed on the surface of antigen-expressing mammalian cells. The library underwent interaction with an exogenous reference antibody (rAb), after which the rAb-non-binding cells were sorted using FACS. DNA sequencing of these sorted cells enabled the identification of qAbs targeting an epitope similar to that of the rAb.