Development of a rapid pandemic response platform to identify antibodies against SARS-CoV-2
Buchanan, Ciara
(2024)
Development of a rapid pandemic response platform to identify antibodies against SARS-CoV-2.
PhD thesis, Dublin City University.
The primary focus of this thesis is the development of a rapid antibody discovery platform which can facilitate accelerated antibody identification in response to an emerging pandemic. Rapidly identifying the right functional antibody candidates can allow a rapid response to emerging infectious disease threats and provide much needed passive therapy for patients. Utilising a function first approach to screening focuses antibody selection to those that are most likely to provide the greatest therapeutic benefit such as those antibodies that exhibit potent virus neutralisation. By utilising a novel high- throughput screening platform, of which the core technology is a microcapillary array for cell screening, mass scale functional screening has been applied in this research to identify a panel of functional anti-SARS-CoV-2 antibodies. High-throughput screening assays were initially developed to facilitate the identification of SARS-CoV-2 binding and functional ACE2 blocking antibodies. To demonstrate the application of the technology as a rapid pandemic response platform, three independent antibody discovery campaigns were undertaken. Functional RBD binding and ACE2 blocking VHH antibody fragments were identified directly from an immune RBD camelid library and a high-affinity virus neutralising monoclonal antibody has been identified from a recombinant COVID-19 convalescent donor scFv library, both without prior enrichment by phage display. Monoclonal antibodies have also been identified directly from screening single B cells of a convalescent COVID-19 donor which demonstrate specify towards multiple SARS-CoV-2 variants. Together the results from the three antibody discovery campaigns described herein, showcase the development and implementation of a rapid antibody discovery platform for the identification of promising anti-SARS- CoV-2 antibody candidates. Multiple potentially therapeutic antibodies, including functional VHH, chimeric (camelid/human) VHH-Fc fusions, scFv and patient derived monoclonal antibodies against several SARS-CoV-2 variants have been identified within this work