Isolation and Characterization of Neutralizing Monoclonal Antibodies from a Large Panel of Murine Antibodies against RBD of the SARS-CoV-2 Spike Protein

Emanuela D'Acunto; Alessia Muzi; Silvia Marchese; Lorena Donnici; Valerio Chiarini; Federica Bucci; Emiliano Pavoni; Fabiana Fosca Ferrara; Manuela Cappelletti; Roberto Arriga; Silvia Maria Serrao; Valentina Peluzzi; Eugenia Principato; Mirco Compagnone; Eleonora Pinto; Laura Luberto; Daniela Stoppoloni; Armin Lahm; Rüdiger Groß; Alina Seidel; Lukas Wettstein; Jan Münch; Andrew Goodhead; Judicael Parisot; Raffaele De Francesco; Gennaro Ciliberto; Emanuele Marra; Luigi Aurisicchio; Giuseppe Roscilli

doi:10.3390/antib13010005

Isolation and Characterization of Neutralizing Monoclonal Antibodies from a Large Panel of Murine Antibodies against RBD of the SARS-CoV-2 Spike Protein

Antibodies (Basel). 2024 Jan 5;13(1):5. doi: 10.3390/antib13010005.

Authors

Emanuela D'Acunto¹, Alessia Muzi¹, Silvia Marchese^{2

3}, Lorena Donnici^{2

3}, Valerio Chiarini⁴, Federica Bucci¹, Emiliano Pavoni¹, Fabiana Fosca Ferrara¹, Manuela Cappelletti¹, Roberto Arriga¹, Silvia Maria Serrao¹, Valentina Peluzzi^{1

5}, Eugenia Principato^{1

6}, Mirco Compagnone⁴, Eleonora Pinto¹, Laura Luberto¹, Daniela Stoppoloni¹, Armin Lahm¹, Rüdiger Groß⁷, Alina Seidel⁷, Lukas Wettstein⁷, Jan Münch⁷, Andrew Goodhead⁸, Judicael Parisot⁸, Raffaele De Francesco^{2

3}, Gennaro Ciliberto⁹, Emanuele Marra¹, Luigi Aurisicchio¹, Giuseppe Roscilli¹

Affiliations

¹ Takis Biotech, 00128 Rome, Italy.
² INGM-Istituto Nazionale di Genetica Molecolare "Romeo ed Erica Invernizzi", 20122 Milan, Italy.
³ Department of Pharmacological and Biomolecular Sciences (DiSFeB), University of Milan, 20133 Milan, Italy.
⁴ Evvivax Biotech, 00128 Rome, Italy.
⁵ Department of Engineering, Università Campus Bio-Medico di Roma, 00128 Rome, Italy.
⁶ Department of Experimental and Clinical Medicine, University Magna Graecia, 88100 Catanzaro, Italy.
⁷ Institute of Molecular Virology, Ulm University Medical Center, 89081 Ulm, Germany.
⁸ Carterra, 825 N. 300 W., Suite C309, Salt Lake City, UT 84103, USA.
⁹ Tumor Immunology and Immunotherapy Unit, IRCSS Regina Elena National Cancer Institute, 00144 Rome, Italy.

Abstract

The COVID-19 pandemic, once a global crisis, is now largely under control, a testament to the extraordinary global efforts involving vaccination and public health measures. However, the relentless evolution of SARS-CoV-2, leading to the emergence of new variants, continues to underscore the importance of remaining vigilant and adaptable. Monoclonal antibodies (mAbs) have stood out as a powerful and immediate therapeutic response to COVID-19. Despite the success of mAbs, the evolution of SARS-CoV-2 continues to pose challenges and the available antibodies are no longer effective. New variants require the ongoing development of effective antibodies. In the present study, we describe the generation and characterization of neutralizing mAbs against the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein by combining plasmid DNA and recombinant protein vaccination. By integrating genetic immunization for rapid antibody production and the potent immune stimulation enabled by protein vaccination, we produced a rich pool of antibodies, each with unique binding and neutralizing specificities, tested with the ELISA, BLI and FACS assays and the pseudovirus assay, respectively. Here, we present a panel of mAbs effective against the SARS-CoV-2 variants up to Omicron BA.1 and BA.5, with the flexibility to target emerging variants. This approach ensures the preparedness principle is in place to address SARS-CoV-2 actual and future infections.

Keywords: SARS-CoV-2; betacoronaviruses; mAb panel; neutralizing antibodies; pancoronavirus; pandemic preparedness.

Grants and funding

J.M. acknowledges funding by the German Research Foundation through CRC 1279. J.M. was further supported by the Ministry of Science, Research and the Arts of Baden-Württemberg as part of the new special funding line COVID-19, which is part of the measures to combat the Coronavirus SARS-CoV-2 pandemic in the field of medical research. A.S. and L.W. are part of the International Graduate School in Molecular Medicine Ulm. Takis is also grateful to Lazio Innova for the funding for the GENERAS project, which is part of the measures to combat the Coronavirus SARS-CoV-2 pandemic in the Lazio Region, Italy.