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Bispecific IgG neutralizes SARS-CoV-2 variants and prevents escape in mice

De Gasparo, Raoul and Pedotti, Mattia and Simonelli, Luca and Nickl, Petr and Muecksch, Frauke and Cassaniti, Irene and Percivalle, Elena and Lorenzi, Julio C. C. and Mazzola, Federica and Magrì, Davide and Michalcikova, Tereza and Haviernik, Jan and Hönig, Václav and Mrazkova, Blanka and Polakova, Natalie and Fortova, Andrea and Tureckova, Jolana and Iatsiuk, Veronika and Di Girolamo, Salvatore and Palus, Martin and Zudova, Dagmar and Bednar, Petr and Bukova, Ivana and Bianchini, Filippo and Mehn, Dora and Nencka, Radim and Strakova, Petra and Pavlis, Oto and Rozman, Jan and Gioria, Sabrina and Camilla Sammartino, Josè and Giardina, Federica and Gaiarsa, Stefano and Pan-Hammarström, Qiang and Barnes, Christopher O. and Bjorkman, Pamela J. and Calzolai, Luigi and Piralla, Antonio and Baldanti, Fausto and Nussenzweig, Michel C. and Bieniasz, Paul D. and Hatziioannou, Theodora and Prochazka, Jan and Sedlacek, Radislav and Robbiani, Davide F. and Růžek, Daniel and Varani, Luca (2021) Bispecific IgG neutralizes SARS-CoV-2 variants and prevents escape in mice. Nature, 593 (7859). pp. 424-428. ISSN 0028-0836. PMCID PMC8330819. doi:10.1038/s41586-021-03461-y.

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PDF (Supplementary Figure 1) - Supplemental Material
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[img] PDF (Reporting Summary) - Supplemental Material
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[img] MS Excel (Source Data Fig. 2) - Supplemental Material
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[img] Image (JPEG) (Extended Data Fig. 1: Neutralization of SARS-CoV-2 pseudovirus by bispecific antibodies) - Supplemental Material
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[img] Image (JPEG) (Extended Data Fig. 2: CoV-X2 engages its epitopes on all RBD conformations on the S trimer) - Supplemental Material
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[img] Image (JPEG) (Extended Data Fig. 3: CoV-X2 and its parental monoclonal antibodies bind recombinant, isolated RBD and S trimer with low nanomolar affinity) - Supplemental Material
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[img] Image (JPEG) (Extended Data Fig. 4: CoV-X2 binds with low-nanomolar affinity to S mutants, including some mutants that are not recognized by the parental monoclonal antibodies C121 and C135) - Supplemental Material
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[img] Image (JPEG) (Extended Data Fig. 5: Efficacy of CoV-X2 against the B.1.1.7 and B.1.351 variants) - Supplemental Material
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[img] Image (JPEG) (Extended Data Fig. 6: SPR-based avidity assays confirm that CoV-X2 can engage bivalently on a single RBD) - Supplemental Material
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[img] Image (JPEG) (Extended Data Fig. 7: Generation of the AAV-hACE2-transduced mouse model of COVID-19) - Supplemental Material
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[img] Image (JPEG) (Extended Data Fig. 8: Natural SARS-CoV-2 variants in the C121 and C135 epitopes) - Supplemental Material
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[img] Image (JPEG) (Extended Data Table 1 Summary of the P values for the mouse protection experiment) - Supplemental Material
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Neutralizing antibodies that target the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein are among the most promising approaches against COVID-19. A bispecific IgG1-like molecule (CoV-X2) has been developed on the basis of C121 and C135, two antibodies derived from donors who had recovered from COVID-19. Here we show that CoV-X2 simultaneously binds two independent sites on the RBD and, unlike its parental antibodies, prevents detectable spike binding to the cellular receptor of the virus, angiotensin-converting enzyme 2 (ACE2). Furthermore, CoV-X2 neutralizes wild-type SARS-CoV-2 and its variants of concern, as well as escape mutants generated by the parental monoclonal antibodies. We also found that in a mouse model of SARS-CoV-2 infection with lung inflammation, CoV-X2 protects mice from disease and suppresses viral escape. Thus, the simultaneous targeting of non-overlapping RBD epitopes by IgG-like bispecific antibodies is feasible and effective, and combines the advantages of antibody cocktails with those of single-molecule approaches.

Item Type:Article
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URLURL TypeDescription ReadCube access Correction ReadCube access - Publisher Correction Paper CentralPublisher Correction
Pedotti, Mattia0000-0003-1370-9505
Simonelli, Luca0000-0001-6331-7716
Muecksch, Frauke0000-0002-0132-5101
Cassaniti, Irene0000-0002-3385-2088
Percivalle, Elena0000-0002-3355-1410
Lorenzi, Julio C. C.0000-0003-2492-3961
Magrì, Davide0000-0003-3790-5332
Michalcikova, Tereza0000-0002-0172-2254
Haviernik, Jan0000-0001-9376-957X
Hönig, Václav0000-0003-0469-4604
Mrazkova, Blanka0000-0003-1985-2361
Tureckova, Jolana0000-0002-4445-1538
Palus, Martin0000-0002-4279-7092
Bianchini, Filippo0000-0002-0746-7629
Mehn, Dora0000-0003-3482-2996
Nencka, Radim0000-0001-6167-0380
Strakova, Petra0000-0002-3130-933X
Pavlis, Oto0000-0002-4453-4421
Rozman, Jan0000-0002-8035-8904
Camilla Sammartino, Josè0000-0003-3707-3118
Giardina, Federica0000-0002-3710-0940
Pan-Hammarström, Qiang0000-0003-1990-8804
Barnes, Christopher O.0000-0003-2754-5951
Bjorkman, Pamela J.0000-0002-2277-3990
Calzolai, Luigi0000-0002-8474-7974
Piralla, Antonio0000-0002-6062-2579
Baldanti, Fausto0000-0002-3358-8969
Nussenzweig, Michel C.0000-0003-0592-8564
Bieniasz, Paul D.0000-0002-2368-3719
Hatziioannou, Theodora0000-0002-7889-0766
Prochazka, Jan0000-0003-4675-8995
Sedlacek, Radislav0000-0002-3352-392X
Robbiani, Davide F.0000-0001-7379-3484
Růžek, Daniel0000-0003-4655-2380
Varani, Luca0000-0002-0963-0987
Alternate Title:Bispecific antibody neutralizes circulating SARS-CoV-2 variants, prevents escape and protects mice from disease
Additional Information:© The Author(s), under exclusive licence to Springer Nature Limited 2021. Received 07 January 2021; Accepted 16 March 2021; Published 25 March 2021. D.F.R., L.V., Q.P.-H., F.Baldanti and L.C. have received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement no. 101003650. This work was also supported by SNF grant 31003A_182270 (L.V.); Lions Club Monteceneri (L.V.); George Mason University Fast Grant and IRB start-up funds (D.F.R.); NIH U01 AI151698 for the United World Antiviral Research Network (UWARN) (D.F.R. and M.C.N.); NIH grant P01-AI138398-S1 (M.C.N. and P.J.B.); 2U19AI111825 (M.C.N. and D.F.R.); the Caltech Merkin Institute for Translational Research and P50 AI150464 (P.J.B.); R37-AI64003 (P.D.B.); and R01AI78788 (T.H.); P.D.B. and M.C.N. are Howard Hughes Medical Institute Investigators. The study was also supported by the Czech Academy of Sciences and Czech Ministry of Agriculture (RVO 68378050 (R.S.) and RVO0518 (D.R.)); Czech Ministry of Education, Youth and Sports and the European Regional Development Fund (LM2018126; CZ.1.05/2.1.00/19.0395 and CZ.1.05/1.1.00/02.0109 (R.S.) and CZ.02.1.01/0.0/0.0/15_003/0000495 (D.R.)); Czech Science Foundation (20-14325S (D.R.)); the Bulgari Women & Science Fellowship in COVID-19 Research (F. Muecksch); the EU Joint Research Centre Exploratory Research program ('NanoMicrobials′; D. Magrì); and by Ricerca Finalizzata from Ministry of Health, Italy (grant no. GR-2013-02358399 (A.P.)). We are grateful for the high-performance computing resources that were provided by S. Bassini of CINECA to M. Hust, F. Bertoglio, F. Bognuda and E. Restivo. We thank V. Zatecka, V. Martinkova and L. Kutlikova for technical assistance; and V. Babak for help with statistical analyses. We are grateful to the late F. Diederich for their mentorship. Data availability: The data that support the findings of this study are available within the Article and its Supplementary Information. Any other data are available from the corresponding author upon reasonable request. Published data were taken from GenBank (, UniProt (, PDB ( and the ViPR database ( Source data are provided with this paper. These authors contributed equally: Raoul De Gasparo, Mattia Pedotti. Author Contributions: R.D.G, M. Pedotti, L.S., F. Muecksch, J.C.C.L., F. Mazzola, D. Magrì, I.C., E.P., S.D.G., M. Palus, D. Mehn, S. Gioria, C.O.B., F. Bianchini, J.C.S., F.G. and S. Gaiarsa designed and carried out experiments and analysed results, and produced plasmids, antibodies and viral proteins. P.N., T.M., J.H., V.H, B.M., N.P., A.F., J.T., V.I., M. Palus, D.Z., P.B., I.B., P.S. and D.R., performed mouse experiments and analysed the results. L.V., D.F.R., D.R., Q.P.-H., F. Baldanti, A.P., L.C., P.J.B., M.C.N., P.D.B. and T.H. conceived and designed study and experiments, and analysed the results. P.N., T.M., R.N., O.P., J.P., J.R. and R.S. conceived and designed the mouse model. L.V., D.F.R., D.R. and R.D.G. wrote the manuscript, with input from all co-authors. Competing interests: The Institute for Research in Biomedicine has filed a provisional European patent application in connection with this work, on which L.V. is inventor (PCT/EP2020/085342). The Rockefeller University has filed a provisional US patent application (US 63/021,387) on coronavirus antibodies, on which D.F.R. and M.C.N. are inventors. Peer review information: Nature thanks Stanley Perlman and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.
Errata:De Gasparo, R., Pedotti, M., Simonelli, L. et al. Publisher Correction: Bispecific IgG neutralizes SARS-CoV-2 variants and prevents escape in mice. Nature (2021).
Group:COVID-19, Richard N. Merkin Institute for Translational Research
Funding AgencyGrant Number
European Research Council (ERC)101003650
Swiss National Science Foundation (SNSF)31003A_182270
Lions Club MonteceneriUNSPECIFIED
George Mason UniversityUNSPECIFIED
NIHU01 AI151698
Caltech Merkin Institute for Translational ResearchUNSPECIFIED
NIHP50 AI150464
Howard Hughes Medical Institute (HHMI)UNSPECIFIED
Czech Academy of SciencesUNSPECIFIED
Ministry of Agriculture (Czech Republic)RVO 68378050
Ministry of Agriculture (Czech Republic)RVO0518
Ministry of Education, Youth and Sports (Czech Republic)UNSPECIFIED
European Regional Development FundLM2018126
European Regional Development FundCZ.1.05/2.1.00/19.0395
European Regional Development FundCZ.1.05/1.1.00/02.0109
European Regional Development FundCZ.02.1.01/0.0/0.0/15_003/0000495
Czech Science Foundation20-14325S
Bulgari Women & Science Fellowship in COVID-19 ResearchUNSPECIFIED
European Union Joint Research Centre Exploratory Research ProgramUNSPECIFIED
Ricerca FinalizzataGR-2013-02358399
Ministero della Salute (Italy)UNSPECIFIED
Subject Keywords:Antibody therapy; Immunization; Protein design; SARS-CoV-2; Viral infection
Issue or Number:7859
PubMed Central ID:PMC8330819
Record Number:CaltechAUTHORS:20210308-130543968
Persistent URL:
Official Citation:De Gasparo, R., Pedotti, M., Simonelli, L. et al. Bispecific IgG neutralizes SARS-CoV-2 variants and prevents escape in mice. Nature 593, 424–428 (2021).
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:108344
Deposited By: Tony Diaz
Deposited On:08 Mar 2021 23:38
Last Modified:11 Aug 2021 22:39

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