CORONAVIRUS NEUTRALIZING COMPOSITIONS AND ASSOCIATED METHODS
Provided are fusion proteins and modified proteins comprising a neutralizing polypeptide and an antibody (e.g., a non-neutralizing antibody) that specifically binds to an epitope in a conserved region of one or more coronavirus spike proteins. The fusion proteins and modified proteins are able to specifically bind to and neutralize a broad spectrum of coronaviruses, including SARS-CoV-2 and all known SARS-COV-2 variants of concern (e.g., the Delta and Omicron variants). Also provided are various compositions of such proteins, methods of their use, nucleic acids encoding such proteins or domains thereof, constructs, expression cassettes, and vectors containing such nucleic acids, and host cells capable of expressing these proteins or domains thereof. Additionally provided are prophylactic and therapeutic methods employing the fusion proteins and/or modified proteins of the disclosure.
1 . A fusion protein comprising a neutralizing polypeptide that binds to a receptor binding domain (RBD) of a first coronavirus spike protein, a peptide linker, and an antibody that specifically binds an epitope in a conserved region of a second coronavirus spike protein.
2 . The fusion protein of claim 1 , wherein the neutralizing polypeptide is a coronavirus receptor polypeptide.
3 . The fusion protein of claim 2 , wherein the coronavirus receptor polypeptide comprises an ACE2 receptor ectodomain polypeptide or a DPP4 receptor ectodomain polypeptide.
4 . The fusion protein of claim 1 , wherein the neutralizing polypeptide is a neutralizing antibody or a non-neutralizing antibody.
5 . (canceled)
6 . The fusion protein of claim 1 , wherein the conserved region comprises 90% or greater conservation across related coronaviruses.
7 . The fusion protein of claim 6 , wherein the related coronaviruses comprise spike proteins with amino acid sequences having 40% or greater amino acid sequence identity to SEQ ID NO:337.
8 - 9 . (canceled)
10 . The fusion protein of claim 1 , wherein the first coronavirus spike protein and the second coronavirus spike protein are the same protein or different coronavirus spike proteins.
11 . The fusion protein of claim 1 , wherein the neutralizing polypeptide and the antibody that specifically binds an epitope in a conserved region of the second coronavirus spike protein do not bind competitively to their respective binding sites.
12 . (canceled)
13 . The fusion protein of claim 3 , wherein the ACE2 receptor ectodomain polypeptide comprises an amino acid sequence having at least 90% sequence identity to the amino acid sequence as set forth in SEQ ID NO:270 or SEQ ID NO:271, and/or wherein the DPP4 receptor ectodomain polypeptide comprises an amino acid sequence having at least 90% sequence identity to the amino acid sequence as set forth in SEQ ID NO:273 or SEQ ID NO:274.
14 . (canceled)
15 . The fusion protein of claim 1 , wherein the antibody that specifically binds an epitope in a conserved region of the second coronavirus spike protein comprises:
(a) a heavy chain variable region comprising
(i) a CDRH1 comprising any of SEQ ID NOs: 153-170
(ii) a CDRH2 comprising any of SEQ ID NOs: 171-188
(iii) a CDRH3 comprising any of SEQ ID NOs: 189-214 and
(b) a light chain variable region comprising
(i) a CDRL1 comprising any of SEQ ID NOs: 215-232
(ii) a CDRL2 compring any of SEQ ID NOs: 233-241
(iii) a CDRL3 comprising any of SEQ ID NOs: 242-268.
16 . The fusion protein of claim 1 , wherein the antibody that specifically binds an epitope in a conserved region of the second coronavirus spike protein comprises a heavy chain variable region having at least 90% sequence identity to any of SEQ ID NOs: 1-7, 11-15, 17-23, 26, 29-32, 34, 35, 37, and 38 and a light chain variable region having at least 90% sequence identity to any of SEQ ID NOs: 77-83, 87-91, 93-99, 102, 105-108, 110, 111, 113, and 114, and wherein the conserved region is a region of a SARS-COV-2 spike protein.
17 - 18 . (canceled)
19 . The fusion protein of claim 1 , wherein the fusion protein has at least one of: about 1000-fold increased neutralization potency for SARS-CoV-2 relative to the cleaved fusion protein domains, about 44-fold increased neutralization potency for SARS-COV-2, or about 13-fold increased neutralization potency for SARS-COV-1 relative to bivalent ACE2, about 376-fold increased neutralization potency for SARS-COV-2, or about 1162-fold increased neutralization potency for SARS-COV-1 relative to monovalent ACE2.
20 - 21 . (canceled)
22 . A recombinant nucleic acid encoding the fusion protein of claim 1 .
23 . A DNA construct comprising a promoter operably linked to the recombinant nucleic acid of claim 22 .
24 . A vector comprising the DNA construct of claim 23 .
25 . A host cell comprising the recombinant nucleic acid of claim 22 .
26 - 28 . (canceled)
29 . A method of producing a fusion protein comprising culturing the host cell of claim 25 , under conditions sufficient for the production of the fusion protein by the host cell.
30 . A pharmaceutical preparation comprising:
(a) the fusion protein of claim 1 ; and
(b) a pharmaceutically acceptable carrier.
31 . A method for treating a subject infected with a SARS-COV-2 virus or having symptoms suggestive of a SARS-COV-2 infection, the method comprising administering to the subject a therapeutically effective amount of the pharmaceutical preparation of claim 30 .
32 . (canceled)
33 . A method for treating a subject exposed to a SARS-COV-2 virus or at risk of exposure to SARS-COV-2 virus, the method comprising administering to the subject a therapeutically effective amount of the pharmaceutical preparation of claim 30 .
34 - 36 . (canceled)