Capture and display of antibodies secreted by hybridoma cells enables fluorescent on-cell screening

Hybridoma methods for monoclonal antibody (mAb) cloning are a mainstay of biomedical research, but they are hindered by the need to maintain hybridomas in oligoclonal pools during antibody screening. Here, we describe a system in which hybridomas specifically capture and display the mAbs they secrete: On-Cell mAb Screening (OCMS?). In OCMS?, mAbs displayed on the cell surface can be rapidly assayed for expression level and binding specificity using fluorescent antigens with high-content (image-based) methods or flow cytometry. OCMS? demonstrated specific mAb binding to poliovirus and rabies virus by forming a cell surface IgG “cap”, as a universal assay for anti-viral mAbs. We produced and characterized OCMS?-enabled hybridomas secreting mAbs that neutralize poliovirus and used fluorescence microscopy to identify and clone a human mAb specific for the human N-methyl-D-aspartate receptor. Lastly, we used OCMS? to assess expression and antigen binding of a recombinant mAb produced in 293T cells. As a novel method to physically associate mAbs with the hybridomas that secrete them, OCMS? overcomes a central challenge to hybridoma mAb screening and offers new paradigms for mAb discovery and production.