WO2022167947A1 - Mutated recombinant ace2-fc fusion proteins for the treatment of covid-19 infections - Google Patents
Mutated recombinant ace2-fc fusion proteins for the treatment of covid-19 infections Download PDFInfo
- Publication number
- WO2022167947A1 WO2022167947A1 PCT/IB2022/050901 IB2022050901W WO2022167947A1 WO 2022167947 A1 WO2022167947 A1 WO 2022167947A1 IB 2022050901 W IB2022050901 W IB 2022050901W WO 2022167947 A1 WO2022167947 A1 WO 2022167947A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- fusion protein
- ace2
- recombinant fusion
- domain
- mutated recombinant
- Prior art date
Links
- 208000025721 COVID-19 Diseases 0.000 title claims description 5
- 102000037865 fusion proteins Human genes 0.000 title description 50
- 108020001507 fusion proteins Proteins 0.000 title description 50
- 238000011282 treatment Methods 0.000 title description 12
- 108010008281 Recombinant Fusion Proteins Proteins 0.000 claims abstract description 143
- 102000007056 Recombinant Fusion Proteins Human genes 0.000 claims abstract description 143
- 102000053723 Angiotensin-converting enzyme 2 Human genes 0.000 claims abstract description 98
- 108090000975 Angiotensin-converting enzyme 2 Proteins 0.000 claims abstract description 98
- 230000035772 mutation Effects 0.000 claims abstract description 79
- 241000711573 Coronaviridae Species 0.000 claims abstract description 58
- 208000037265 diseases, disorders, signs and symptoms Diseases 0.000 claims abstract description 58
- 208000015181 infectious disease Diseases 0.000 claims abstract description 54
- 101000929928 Homo sapiens Angiotensin-converting enzyme 2 Proteins 0.000 claims abstract description 41
- 102000048657 human ACE2 Human genes 0.000 claims abstract description 41
- 108010076504 Protein Sorting Signals Proteins 0.000 claims abstract description 40
- 238000000034 method Methods 0.000 claims abstract description 30
- 108091033319 polynucleotide Proteins 0.000 claims abstract description 11
- 102000040430 polynucleotide Human genes 0.000 claims abstract description 11
- 239000002157 polynucleotide Substances 0.000 claims abstract description 11
- 239000013598 vector Substances 0.000 claims abstract description 8
- 241001678559 COVID-19 virus Species 0.000 claims description 29
- 101100454807 Caenorhabditis elegans lgg-1 gene Proteins 0.000 claims description 29
- 210000004027 cell Anatomy 0.000 description 52
- 230000000694 effects Effects 0.000 description 38
- 241000700605 Viruses Species 0.000 description 34
- 235000018102 proteins Nutrition 0.000 description 30
- 102000004169 proteins and genes Human genes 0.000 description 30
- 108090000623 proteins and genes Proteins 0.000 description 30
- 108090000765 processed proteins & peptides Proteins 0.000 description 23
- 239000006144 Dulbecco’s modified Eagle's medium Substances 0.000 description 16
- 230000006870 function Effects 0.000 description 16
- 239000012636 effector Substances 0.000 description 14
- 238000010790 dilution Methods 0.000 description 12
- 239000012895 dilution Substances 0.000 description 12
- 239000000463 material Substances 0.000 description 12
- 150000001413 amino acids Chemical group 0.000 description 11
- 238000003556 assay Methods 0.000 description 11
- 201000010099 disease Diseases 0.000 description 11
- 230000002255 enzymatic effect Effects 0.000 description 11
- 238000002474 experimental method Methods 0.000 description 11
- 238000006386 neutralization reaction Methods 0.000 description 11
- 239000006228 supernatant Substances 0.000 description 11
- 102100031673 Corneodesmosin Human genes 0.000 description 10
- 102000005962 receptors Human genes 0.000 description 10
- 108020003175 receptors Proteins 0.000 description 10
- 201000003176 Severe Acute Respiratory Syndrome Diseases 0.000 description 9
- 230000010530 Virus Neutralization Effects 0.000 description 9
- 108010031318 Vitronectin Proteins 0.000 description 9
- 235000001014 amino acid Nutrition 0.000 description 9
- 239000012634 fragment Substances 0.000 description 9
- 230000004927 fusion Effects 0.000 description 9
- 239000000523 sample Substances 0.000 description 9
- 230000003612 virological effect Effects 0.000 description 9
- 229940096437 Protein S Drugs 0.000 description 8
- 229940024606 amino acid Drugs 0.000 description 8
- 238000005259 measurement Methods 0.000 description 7
- 238000002360 preparation method Methods 0.000 description 7
- 230000002829 reductive effect Effects 0.000 description 7
- 102000035195 Peptidases Human genes 0.000 description 6
- 108091005804 Peptidases Proteins 0.000 description 6
- 230000000120 cytopathologic effect Effects 0.000 description 6
- 239000012091 fetal bovine serum Substances 0.000 description 6
- 239000002609 medium Substances 0.000 description 6
- 230000004048 modification Effects 0.000 description 6
- 238000012986 modification Methods 0.000 description 6
- 150000007523 nucleic acids Chemical class 0.000 description 6
- 235000019833 protease Nutrition 0.000 description 6
- 230000001225 therapeutic effect Effects 0.000 description 6
- 102000004190 Enzymes Human genes 0.000 description 5
- 108090000790 Enzymes Proteins 0.000 description 5
- 241000315672 SARS coronavirus Species 0.000 description 5
- 101000629318 Severe acute respiratory syndrome coronavirus 2 Spike glycoprotein Proteins 0.000 description 5
- 238000013459 approach Methods 0.000 description 5
- 238000011304 droplet digital PCR Methods 0.000 description 5
- 230000003993 interaction Effects 0.000 description 5
- 230000003472 neutralizing effect Effects 0.000 description 5
- 108020004707 nucleic acids Proteins 0.000 description 5
- 102000039446 nucleic acids Human genes 0.000 description 5
- 208000024891 symptom Diseases 0.000 description 5
- 102000000844 Cell Surface Receptors Human genes 0.000 description 4
- 108010001857 Cell Surface Receptors Proteins 0.000 description 4
- 241000494545 Cordyline virus 2 Species 0.000 description 4
- 208000001528 Coronaviridae Infections Diseases 0.000 description 4
- 108091028043 Nucleic acid sequence Proteins 0.000 description 4
- 101001028244 Onchocerca volvulus Fatty-acid and retinol-binding protein 1 Proteins 0.000 description 4
- 101710198474 Spike protein Proteins 0.000 description 4
- 238000004113 cell culture Methods 0.000 description 4
- 206010052015 cytokine release syndrome Diseases 0.000 description 4
- 238000011534 incubation Methods 0.000 description 4
- 239000010410 layer Substances 0.000 description 4
- 239000002245 particle Substances 0.000 description 4
- 230000002265 prevention Effects 0.000 description 4
- 102000004196 processed proteins & peptides Human genes 0.000 description 4
- 230000009467 reduction Effects 0.000 description 4
- 208000014673 secondary hemophagocytic lymphohistiocytosis Diseases 0.000 description 4
- 239000000758 substrate Substances 0.000 description 4
- 208000025370 Middle East respiratory syndrome Diseases 0.000 description 3
- 241000127282 Middle East respiratory syndrome-related coronavirus Species 0.000 description 3
- 206010037660 Pyrexia Diseases 0.000 description 3
- 108010067390 Viral Proteins Proteins 0.000 description 3
- 230000000903 blocking effect Effects 0.000 description 3
- 239000000872 buffer Substances 0.000 description 3
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 description 3
- 230000006378 damage Effects 0.000 description 3
- 238000012217 deletion Methods 0.000 description 3
- 230000037430 deletion Effects 0.000 description 3
- 238000001514 detection method Methods 0.000 description 3
- 239000013604 expression vector Substances 0.000 description 3
- 238000000338 in vitro Methods 0.000 description 3
- 238000003780 insertion Methods 0.000 description 3
- 230000037431 insertion Effects 0.000 description 3
- 238000000386 microscopy Methods 0.000 description 3
- 239000013612 plasmid Substances 0.000 description 3
- 229920001184 polypeptide Polymers 0.000 description 3
- 239000011541 reaction mixture Substances 0.000 description 3
- CUKWUWBLQQDQAC-VEQWQPCFSA-N (3s)-3-amino-4-[[(2s)-1-[[(2s)-1-[[(2s)-1-[[(2s,3s)-1-[[(2s)-1-[(2s)-2-[[(1s)-1-carboxyethyl]carbamoyl]pyrrolidin-1-yl]-3-(1h-imidazol-5-yl)-1-oxopropan-2-yl]amino]-3-methyl-1-oxopentan-2-yl]amino]-3-(4-hydroxyphenyl)-1-oxopropan-2-yl]amino]-3-methyl-1-ox Chemical compound C([C@@H](C(=O)N[C@@H]([C@@H](C)CC)C(=O)N[C@@H](CC=1NC=NC=1)C(=O)N1[C@@H](CCC1)C(=O)N[C@@H](C)C(O)=O)NC(=O)[C@@H](NC(=O)[C@H](CCCN=C(N)N)NC(=O)[C@@H](N)CC(O)=O)C(C)C)C1=CC=C(O)C=C1 CUKWUWBLQQDQAC-VEQWQPCFSA-N 0.000 description 2
- 206010001052 Acute respiratory distress syndrome Diseases 0.000 description 2
- PQSUYGKTWSAVDQ-UHFFFAOYSA-N Aldosterone Natural products C1CC2C3CCC(C(=O)CO)C3(C=O)CC(O)C2C2(C)C1=CC(=O)CC2 PQSUYGKTWSAVDQ-UHFFFAOYSA-N 0.000 description 2
- 241000004176 Alphacoronavirus Species 0.000 description 2
- 102000005862 Angiotensin II Human genes 0.000 description 2
- 101800000733 Angiotensin-2 Proteins 0.000 description 2
- 108091003079 Bovine Serum Albumin Proteins 0.000 description 2
- 101710155857 C-C motif chemokine 2 Proteins 0.000 description 2
- 206010011224 Cough Diseases 0.000 description 2
- 241000699802 Cricetulus griseus Species 0.000 description 2
- -1 DNA Chemical class 0.000 description 2
- 108020004414 DNA Proteins 0.000 description 2
- DHMQDGOQFOQNFH-UHFFFAOYSA-N Glycine Chemical compound NCC(O)=O DHMQDGOQFOQNFH-UHFFFAOYSA-N 0.000 description 2
- 108010017213 Granulocyte-Macrophage Colony-Stimulating Factor Proteins 0.000 description 2
- 102100039620 Granulocyte-macrophage colony-stimulating factor Human genes 0.000 description 2
- 102100026120 IgG receptor FcRn large subunit p51 Human genes 0.000 description 2
- 108060003951 Immunoglobulin Proteins 0.000 description 2
- 206010061218 Inflammation Diseases 0.000 description 2
- 102100034349 Integrase Human genes 0.000 description 2
- ZDXPYRJPNDTMRX-VKHMYHEASA-N L-glutamine Chemical compound OC(=O)[C@@H](N)CCC(N)=O ZDXPYRJPNDTMRX-VKHMYHEASA-N 0.000 description 2
- 229930182816 L-glutamine Natural products 0.000 description 2
- QEFRNWWLZKMPFJ-ZXPFJRLXSA-N L-methionine (R)-S-oxide Chemical compound C[S@@](=O)CC[C@H]([NH3+])C([O-])=O QEFRNWWLZKMPFJ-ZXPFJRLXSA-N 0.000 description 2
- QEFRNWWLZKMPFJ-UHFFFAOYSA-N L-methionine sulphoxide Natural products CS(=O)CCC(N)C(O)=O QEFRNWWLZKMPFJ-UHFFFAOYSA-N 0.000 description 2
- 206010035664 Pneumonia Diseases 0.000 description 2
- 238000011053 TCID50 method Methods 0.000 description 2
- 239000007983 Tris buffer Substances 0.000 description 2
- 108060008682 Tumor Necrosis Factor Proteins 0.000 description 2
- 102000000852 Tumor Necrosis Factor-alpha Human genes 0.000 description 2
- 230000003213 activating effect Effects 0.000 description 2
- 229960002478 aldosterone Drugs 0.000 description 2
- 230000003321 amplification Effects 0.000 description 2
- 239000012491 analyte Substances 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 229950006323 angiotensin ii Drugs 0.000 description 2
- 230000033228 biological regulation Effects 0.000 description 2
- 239000013553 cell monolayer Substances 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 210000004978 chinese hamster ovary cell Anatomy 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 230000029087 digestion Effects 0.000 description 2
- 230000003292 diminished effect Effects 0.000 description 2
- 238000010828 elution Methods 0.000 description 2
- 238000011156 evaluation Methods 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 230000012010 growth Effects 0.000 description 2
- 210000000987 immune system Anatomy 0.000 description 2
- 102000018358 immunoglobulin Human genes 0.000 description 2
- 230000001976 improved effect Effects 0.000 description 2
- 230000001965 increasing effect Effects 0.000 description 2
- 239000003446 ligand Substances 0.000 description 2
- 238000012417 linear regression Methods 0.000 description 2
- 210000002540 macrophage Anatomy 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 239000012528 membrane Substances 0.000 description 2
- 238000001000 micrograph Methods 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000002052 molecular layer Substances 0.000 description 2
- 238000003199 nucleic acid amplification method Methods 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 210000001672 ovary Anatomy 0.000 description 2
- 244000052769 pathogen Species 0.000 description 2
- 239000013610 patient sample Substances 0.000 description 2
- 239000012071 phase Substances 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 238000000746 purification Methods 0.000 description 2
- 230000036454 renin-angiotensin system Effects 0.000 description 2
- 210000002345 respiratory system Anatomy 0.000 description 2
- 208000037921 secondary disease Diseases 0.000 description 2
- 238000003998 size exclusion chromatography high performance liquid chromatography Methods 0.000 description 2
- 230000003595 spectral effect Effects 0.000 description 2
- 230000007480 spreading Effects 0.000 description 2
- 238000003892 spreading Methods 0.000 description 2
- UCSJYZPVAKXKNQ-HZYVHMACSA-N streptomycin Chemical compound CN[C@H]1[C@H](O)[C@@H](O)[C@H](CO)O[C@H]1O[C@@H]1[C@](C=O)(O)[C@H](C)O[C@H]1O[C@@H]1[C@@H](NC(N)=N)[C@H](O)[C@@H](NC(N)=N)[C@H](O)[C@H]1O UCSJYZPVAKXKNQ-HZYVHMACSA-N 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- 230000009469 supplementation Effects 0.000 description 2
- 238000002560 therapeutic procedure Methods 0.000 description 2
- 210000001519 tissue Anatomy 0.000 description 2
- 238000001890 transfection Methods 0.000 description 2
- 230000001960 triggered effect Effects 0.000 description 2
- 238000000870 ultraviolet spectroscopy Methods 0.000 description 2
- 229960005486 vaccine Drugs 0.000 description 2
- 230000035899 viability Effects 0.000 description 2
- 125000001917 2,4-dinitrophenyl group Chemical group [H]C1=C([H])C(=C([H])C(=C1*)[N+]([O-])=O)[N+]([O-])=O 0.000 description 1
- JKMHFZQWWAIEOD-UHFFFAOYSA-N 2-[4-(2-hydroxyethyl)piperazin-1-yl]ethanesulfonic acid Chemical compound OCC[NH+]1CCN(CCS([O-])(=O)=O)CC1 JKMHFZQWWAIEOD-UHFFFAOYSA-N 0.000 description 1
- 108020003589 5' Untranslated Regions Proteins 0.000 description 1
- RZVAJINKPMORJF-UHFFFAOYSA-N Acetaminophen Chemical compound CC(=O)NC1=CC=C(O)C=C1 RZVAJINKPMORJF-UHFFFAOYSA-N 0.000 description 1
- 241000004177 Alphacoronavirus 1 Species 0.000 description 1
- 102220614025 Angiotensin-converting enzyme 2_N33D_mutation Human genes 0.000 description 1
- DCXYFEDJOCDNAF-UHFFFAOYSA-N Asparagine Natural products OC(=O)C(N)CC(N)=O DCXYFEDJOCDNAF-UHFFFAOYSA-N 0.000 description 1
- 241000008921 Avian coronavirus Species 0.000 description 1
- 208000035143 Bacterial infection Diseases 0.000 description 1
- 241000008922 Beluga Whale coronavirus SW1 Species 0.000 description 1
- 241000008904 Betacoronavirus Species 0.000 description 1
- 241000008905 Betacoronavirus 1 Species 0.000 description 1
- 108010017384 Blood Proteins Proteins 0.000 description 1
- 102000004506 Blood Proteins Human genes 0.000 description 1
- 241000711443 Bovine coronavirus Species 0.000 description 1
- 241001218594 Bulbul coronavirus HKU11 Species 0.000 description 1
- 102100021943 C-C motif chemokine 2 Human genes 0.000 description 1
- 101100454808 Caenorhabditis elegans lgg-2 gene Proteins 0.000 description 1
- 101100217502 Caenorhabditis elegans lgg-3 gene Proteins 0.000 description 1
- 208000024172 Cardiovascular disease Diseases 0.000 description 1
- 102000000018 Chemokine CCL2 Human genes 0.000 description 1
- 241000862448 Chlorocebus Species 0.000 description 1
- 241000282552 Chlorocebus aethiops Species 0.000 description 1
- 108020004705 Codon Proteins 0.000 description 1
- 208000035473 Communicable disease Diseases 0.000 description 1
- 101710139375 Corneodesmosin Proteins 0.000 description 1
- 238000001712 DNA sequencing Methods 0.000 description 1
- 241001461743 Deltacoronavirus Species 0.000 description 1
- 101710091045 Envelope protein Proteins 0.000 description 1
- 108091006020 Fc-tagged proteins Proteins 0.000 description 1
- 238000012366 Fed-batch cultivation Methods 0.000 description 1
- 241000008920 Gammacoronavirus Species 0.000 description 1
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 description 1
- 239000004471 Glycine Substances 0.000 description 1
- 102000003886 Glycoproteins Human genes 0.000 description 1
- 108090000288 Glycoproteins Proteins 0.000 description 1
- HVLSXIKZNLPZJJ-TXZCQADKSA-N HA peptide Chemical compound C([C@@H](C(=O)N[C@@H](CC(O)=O)C(=O)N[C@@H](C(C)C)C(=O)N1[C@@H](CCC1)C(=O)N[C@@H](CC(O)=O)C(=O)N[C@@H](CC=1C=CC(O)=CC=1)C(=O)N[C@@H](C)C(O)=O)NC(=O)[C@H]1N(CCC1)C(=O)[C@@H](N)CC=1C=CC(O)=CC=1)C1=CC=C(O)C=C1 HVLSXIKZNLPZJJ-TXZCQADKSA-N 0.000 description 1
- 239000007995 HEPES buffer Substances 0.000 description 1
- 206010019233 Headaches Diseases 0.000 description 1
- 241001123922 Hedgehog coronavirus 1 Species 0.000 description 1
- 241000711467 Human coronavirus 229E Species 0.000 description 1
- 241001109669 Human coronavirus HKU1 Species 0.000 description 1
- 241000482741 Human coronavirus NL63 Species 0.000 description 1
- 241001428935 Human coronavirus OC43 Species 0.000 description 1
- 206010020772 Hypertension Diseases 0.000 description 1
- 108010073807 IgG Receptors Proteins 0.000 description 1
- 102000009490 IgG Receptors Human genes 0.000 description 1
- PVHLMTREZMEJCG-GDTLVBQBSA-N Ile(5)-angiotensin II (1-7) Chemical compound C([C@@H](C(=O)N[C@@H]([C@@H](C)CC)C(=O)N[C@@H](CC=1NC=NC=1)C(=O)N1[C@@H](CCC1)C([O-])=O)NC(=O)[C@@H](NC(=O)[C@H](CCCNC(N)=[NH2+])NC(=O)[C@@H]([NH3+])CC([O-])=O)C(C)C)C1=CC=C(O)C=C1 PVHLMTREZMEJCG-GDTLVBQBSA-N 0.000 description 1
- 102000000588 Interleukin-2 Human genes 0.000 description 1
- 108010002350 Interleukin-2 Proteins 0.000 description 1
- ODKSFYDXXFIFQN-BYPYZUCNSA-N L-arginine Chemical compound OC(=O)[C@@H](N)CCCN=C(N)N ODKSFYDXXFIFQN-BYPYZUCNSA-N 0.000 description 1
- 229930064664 L-arginine Natural products 0.000 description 1
- 235000014852 L-arginine Nutrition 0.000 description 1
- 102000003960 Ligases Human genes 0.000 description 1
- 108090000364 Ligases Proteins 0.000 description 1
- NTCCRGGIJNDEAB-IRXDYDNUSA-N MLN-4760 Chemical compound CC(C)C[C@@H](C(O)=O)N[C@H](C(O)=O)CC1=CN=CN1CC1=CC(Cl)=CC(Cl)=C1 NTCCRGGIJNDEAB-IRXDYDNUSA-N 0.000 description 1
- 102000009571 Macrophage Inflammatory Proteins Human genes 0.000 description 1
- 108010009474 Macrophage Inflammatory Proteins Proteins 0.000 description 1
- 241000008902 Miniopterus bat coronavirus 1 Species 0.000 description 1
- 241000008903 Miniopterus bat coronavirus HKU8 Species 0.000 description 1
- 241000008906 Murine coronavirus Species 0.000 description 1
- 101100226902 Mus musculus Fcrlb gene Proteins 0.000 description 1
- 208000008589 Obesity Diseases 0.000 description 1
- 206010068319 Oropharyngeal pain Diseases 0.000 description 1
- 238000012408 PCR amplification Methods 0.000 description 1
- 229930182555 Penicillin Natural products 0.000 description 1
- JGSARLDLIJGVTE-MBNYWOFBSA-N Penicillin G Chemical compound N([C@H]1[C@H]2SC([C@@H](N2C1=O)C(O)=O)(C)C)C(=O)CC1=CC=CC=C1 JGSARLDLIJGVTE-MBNYWOFBSA-N 0.000 description 1
- 201000007100 Pharyngitis Diseases 0.000 description 1
- 241000008909 Pipistrellus bat coronavirus HKU5 Species 0.000 description 1
- 229920001213 Polysorbate 20 Polymers 0.000 description 1
- 241001461748 Porcine coronavirus HKU15 Species 0.000 description 1
- 101710188315 Protein X Proteins 0.000 description 1
- 206010037423 Pulmonary oedema Diseases 0.000 description 1
- 108010092799 RNA-directed DNA polymerase Proteins 0.000 description 1
- 206010057190 Respiratory tract infections Diseases 0.000 description 1
- 241000004178 Rhinolophus bat coronavirus HKU2 Species 0.000 description 1
- 208000036071 Rhinorrhea Diseases 0.000 description 1
- 206010039101 Rhinorrhoea Diseases 0.000 description 1
- 241000008907 Rousettus bat coronavirus HKU9 Species 0.000 description 1
- 108091005634 SARS-CoV-2 receptor-binding domains Proteins 0.000 description 1
- 208000037750 SARS-CoV-2-related disease Diseases 0.000 description 1
- 241000004179 Scotophilus bat coronavirus 512 Species 0.000 description 1
- 241000008910 Severe acute respiratory syndrome-related coronavirus Species 0.000 description 1
- 102220476219 Solute carrier family 22 member 7_H34I_mutation Human genes 0.000 description 1
- 241000008908 Tylonycteris bat coronavirus HKU4 Species 0.000 description 1
- 208000036142 Viral infection Diseases 0.000 description 1
- 208000027418 Wounds and injury Diseases 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- 238000001042 affinity chromatography Methods 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 108010021281 angiotensin I (1-7) Proteins 0.000 description 1
- 230000010056 antibody-dependent cellular cytotoxicity Effects 0.000 description 1
- 230000005888 antibody-dependent cellular phagocytosis Effects 0.000 description 1
- 229960001230 asparagine Drugs 0.000 description 1
- 235000009582 asparagine Nutrition 0.000 description 1
- 125000000613 asparagine group Chemical group N[C@@H](CC(N)=O)C(=O)* 0.000 description 1
- 239000012131 assay buffer Substances 0.000 description 1
- 208000022362 bacterial infectious disease Diseases 0.000 description 1
- 238000012365 batch cultivation Methods 0.000 description 1
- 239000011324 bead Substances 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 238000010170 biological method Methods 0.000 description 1
- 230000036772 blood pressure Effects 0.000 description 1
- 210000004899 c-terminal region Anatomy 0.000 description 1
- 210000001043 capillary endothelial cell Anatomy 0.000 description 1
- 230000002612 cardiopulmonary effect Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 238000005119 centrifugation Methods 0.000 description 1
- 238000012512 characterization method Methods 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000010367 cloning Methods 0.000 description 1
- 230000024203 complement activation Effects 0.000 description 1
- 230000000295 complement effect Effects 0.000 description 1
- 102000006834 complement receptors Human genes 0.000 description 1
- 108010047295 complement receptors Proteins 0.000 description 1
- 230000009918 complex formation Effects 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 210000004443 dendritic cell Anatomy 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000000779 depleting effect Effects 0.000 description 1
- 206010012601 diabetes mellitus Diseases 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000006806 disease prevention Effects 0.000 description 1
- 238000010494 dissociation reaction Methods 0.000 description 1
- 230000005593 dissociations Effects 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 238000009509 drug development Methods 0.000 description 1
- 238000007876 drug discovery Methods 0.000 description 1
- 208000017574 dry cough Diseases 0.000 description 1
- 230000002526 effect on cardiovascular system Effects 0.000 description 1
- 238000004520 electroporation Methods 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000006911 enzymatic reaction Methods 0.000 description 1
- 238000012869 ethanol precipitation Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 230000007717 exclusion Effects 0.000 description 1
- 239000013613 expression plasmid Substances 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 102000034287 fluorescent proteins Human genes 0.000 description 1
- 108091006047 fluorescent proteins Proteins 0.000 description 1
- 238000003306 harvesting Methods 0.000 description 1
- 231100000869 headache Toxicity 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 210000003958 hematopoietic stem cell Anatomy 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- 230000001900 immune effect Effects 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 238000001727 in vivo Methods 0.000 description 1
- 230000001939 inductive effect Effects 0.000 description 1
- 230000001524 infective effect Effects 0.000 description 1
- 230000036512 infertility Effects 0.000 description 1
- 230000004054 inflammatory process Effects 0.000 description 1
- 239000003112 inhibitor Substances 0.000 description 1
- 208000014674 injury Diseases 0.000 description 1
- 230000010039 intracellular degradation Effects 0.000 description 1
- 238000001990 intravenous administration Methods 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 238000003367 kinetic assay Methods 0.000 description 1
- 230000000670 limiting effect Effects 0.000 description 1
- 206010025482 malaise Diseases 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000001404 mediated effect Effects 0.000 description 1
- 244000005700 microbiome Species 0.000 description 1
- 210000002500 microbody Anatomy 0.000 description 1
- 230000004001 molecular interaction Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 210000001616 monocyte Anatomy 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- 238000010172 mouse model Methods 0.000 description 1
- 201000009240 nasopharyngitis Diseases 0.000 description 1
- 108010068617 neonatal Fc receptor Proteins 0.000 description 1
- 239000002773 nucleotide Substances 0.000 description 1
- 125000003729 nucleotide group Chemical group 0.000 description 1
- 235000020824 obesity Nutrition 0.000 description 1
- 210000000056 organ Anatomy 0.000 description 1
- 230000008520 organization Effects 0.000 description 1
- 230000036961 partial effect Effects 0.000 description 1
- 230000001717 pathogenic effect Effects 0.000 description 1
- 229940049954 penicillin Drugs 0.000 description 1
- 230000035790 physiological processes and functions Effects 0.000 description 1
- 239000000256 polyoxyethylene sorbitan monolaurate Substances 0.000 description 1
- 235000010486 polyoxyethylene sorbitan monolaurate Nutrition 0.000 description 1
- 238000011176 pooling Methods 0.000 description 1
- 230000004481 post-translational protein modification Effects 0.000 description 1
- 230000003449 preventive effect Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000004393 prognosis Methods 0.000 description 1
- 230000000644 propagated effect Effects 0.000 description 1
- 238000012514 protein characterization Methods 0.000 description 1
- 230000006916 protein interaction Effects 0.000 description 1
- 238000001742 protein purification Methods 0.000 description 1
- 208000005333 pulmonary edema Diseases 0.000 description 1
- 238000011002 quantification Methods 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 230000007115 recruitment Effects 0.000 description 1
- 230000010076 replication Effects 0.000 description 1
- 230000000241 respiratory effect Effects 0.000 description 1
- 208000020029 respiratory tract infectious disease Diseases 0.000 description 1
- 108091008146 restriction endonucleases Proteins 0.000 description 1
- 238000010839 reverse transcription Methods 0.000 description 1
- 102220065900 rs200290535 Human genes 0.000 description 1
- 238000013207 serial dilution Methods 0.000 description 1
- 210000002966 serum Anatomy 0.000 description 1
- 230000000391 smoking effect Effects 0.000 description 1
- 239000001509 sodium citrate Substances 0.000 description 1
- NLJMYIDDQXHKNR-UHFFFAOYSA-K sodium citrate Chemical compound O.O.[Na+].[Na+].[Na+].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O NLJMYIDDQXHKNR-UHFFFAOYSA-K 0.000 description 1
- 238000010532 solid phase synthesis reaction Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 229960005322 streptomycin Drugs 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000007910 systemic administration Methods 0.000 description 1
- 230000009885 systemic effect Effects 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000010361 transduction Methods 0.000 description 1
- 230000026683 transduction Effects 0.000 description 1
- 238000013519 translation Methods 0.000 description 1
- 102000035160 transmembrane proteins Human genes 0.000 description 1
- 108091005703 transmembrane proteins Proteins 0.000 description 1
- 230000032258 transport Effects 0.000 description 1
- 238000011269 treatment regimen Methods 0.000 description 1
- LENZDBCJOHFCAS-UHFFFAOYSA-N tris Chemical compound OCC(N)(CO)CO LENZDBCJOHFCAS-UHFFFAOYSA-N 0.000 description 1
- 238000013060 ultrafiltration and diafiltration Methods 0.000 description 1
- 238000002255 vaccination Methods 0.000 description 1
- 238000012795 verification Methods 0.000 description 1
- 230000009385 viral infection Effects 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
- C12N9/00—Enzymes; Proenzymes; Compositions thereof; Processes for preparing, activating, inhibiting, separating or purifying enzymes
- C12N9/14—Hydrolases (3)
- C12N9/48—Hydrolases (3) acting on peptide bonds (3.4)
- C12N9/485—Exopeptidases (3.4.11-3.4.19)
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
- A61K38/00—Medicinal preparations containing peptides
- A61K38/16—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof
- A61K38/17—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof from animals; from humans
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07K—PEPTIDES
- C07K16/00—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies
- C07K16/08—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from viruses
- C07K16/10—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from viruses from RNA viruses
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
- C12N15/00—Mutation or genetic engineering; DNA or RNA concerning genetic engineering, vectors, e.g. plasmids, or their isolation, preparation or purification; Use of hosts therefor
- C12N15/09—Recombinant DNA-technology
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
- C12N9/00—Enzymes; Proenzymes; Compositions thereof; Processes for preparing, activating, inhibiting, separating or purifying enzymes
- C12N9/14—Hydrolases (3)
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12Y—ENZYMES
- C12Y304/00—Hydrolases acting on peptide bonds, i.e. peptidases (3.4)
- C12Y304/17—Metallocarboxypeptidases (3.4.17)
- C12Y304/17023—Angiotensin-converting enzyme 2 (3.4.17.23)
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07K—PEPTIDES
- C07K2319/00—Fusion polypeptide
- C07K2319/30—Non-immunoglobulin-derived peptide or protein having an immunoglobulin constant or Fc region, or a fragment thereof, attached thereto
Definitions
- the present invention relates to mutated recombinant fusion proteins comprising mutated ACE2 domain(s) and/or fragments thereof and Fc domain(s) and their use for the treatment of COVID-19.
- SARS-CoV-2 severe acute respiratory syndrome coronavirus 2
- WHO World Health Organization
- Risk factors are today considered to include male sex, smoking, hypertension, diabetes, obesity and preexisting cardiovascular disease; all of which are associated with an unfavorable prognosis for COVID-19 (Zou et al, N. Engl. J. Med.; 2020, 382, 1177-1179, Section “Findings”). Symptoms of the newly emerged disease COVID-19 include, among others, dry cough and fever and general malaise. The most severe symptoms triggered by SARS-CoV-2 may also include cytokine release syndrome (CRS), which can be associated with various secondary diseases (e.g. pulmonary edema, acute respiratory distress syndrome (ARDS) or secondary hemophagocytic lym phohistiocytosis (sHLH)).
- CRS cytokine release syndrome
- secondary diseases e.g. pulmonary edema, acute respiratory distress syndrome (ARDS) or secondary hemophagocytic lym phohistiocytosis (sHLH)
- patients suffering COVID-19 may develop systemic hyper-inflammation, cause by increased levels of IL-2, II-7, II-6, granulocyte-macrophage colony-stimulating factor (GM-CSF), interferon-gamma- inducible protein 10 (IP-10), monocyte chemoattractant protein 1 (MCP-1 ), macrophage inflammatory protein 1-a (MIP-1a) and the tumor necrosis factor-alpha (TNFa) indicating CRS, as it was shown for example by Huang et al. (The Lancet; 2020, 395, 497-506)
- SARS-CoV-2 binds to the cell surface receptor Angiotensin Converting Enzyme-2 (ACE2) in the body, in order to gain access to the attacked body cells allowing its reproduction.
- ACE2 Angiotensin Converting Enzyme-2
- This receptor is particularly common in cardiopulmonary tissues, but it is also expressed in hematopoietic cells, such as monocytes and macrophages.
- the transmembrane protein natively cleaves angiotensin II within an enzymatic reaction.
- ACE2 thus plays an extremely important role in the renin-angiotensin-aldosterone system (RAAS) and thus in the regulation of fluid balance and blood pressure.
- RAAS renin-angiotensin-aldosterone system
- RBDs receptor-binding domains
- a fragment of the viral protein blocks the cell surface receptor and thus prevents the virus from entering the cell.
- Wong et al. J. Biol. Chem.; 2004, 279, 3197-3201
- monoclonal antibodies also showed a similar effect (Desmyter et al., Proc. Natl. Acad. Sci.; 2013, 110, E1371-E1379; Koch et al., Sci. Rep.; 2017, 7, 8390).
- RBDs have its limitations: this is shown by the fact that in most cases the body produces neutralizing antibodies against RBDs. In addition, the risks of using RBDs have not yet been described adequately. It is not yet known, whether there is a ratio of ACE2 receptors that are needed to be blocked in order to the viral infection to slow down or even halt. It is also questionable, what the density of ACE2 receptors is in certain organs and in the whole body. In addition, it is also possible that blocking ACE2 could ultimately worsen the clinical symptoms of infection by altering the normal physiological functions of ACE2.
- Another strategy deals with the extracellular binding of viral proteins (Li et al., Nature; 2003, 426, 450-454) which are responsible for access to the cell even before the virus docks to the cell.
- soluble forms of the membrane-bound proteins are used to bind and block the virus in advance. It takes advantage of the strong affinity of the spike protein (S protein) to ACE2 to effectively prevent it from binding to the receptor. This technique is used in the present invention.
- Fc-fusion proteins in order to improve half-life extension is commonly used in biomedical science, as long-circulating plasma proteins can result in reduced degradation.
- ACE2-Fc fusion proteins were designed and tested by Liu et al. (Int. J. Biol. Macromol.; 2020, 165: 1626-1633).
- ACE2-Fc mutants of ACE2-Fc (E145A, R273A, H345A, P346A, D368A, H374A, H378A, E402A, H505A) were studied, among them R273A, H378A and E402A were completely lack of ACE2 peptidase activity but maintained their binding capacity toward SARS-CoV-2 spike protein and inhibited the transduction of a pseudotyped reporter virus. According to the conclusions of the article, H378A and E402A mutations may potentially suffer protein instability problems.
- ACE2-Fc lgG1 fusion proteins are described in a preprint article of Iwanaga et al. (bioRxiv; 2020, Version 2.). Three mutants were engineered such as MDR503, MDR504 and MDR505. Among them MDR504 appeared to be the best candidate, which had greater binding to the SARS-CoV-2 RBD and spike protein and showed enhanced neutralization of virus in a Vero E6 cell plaque assay. Furthermore, MDR504 had similar serum stability as wild-type ACE2-Fc.
- MDR503 has a R273A mutation
- MDR504 has a H345A mutation
- MDR505 has both R273A and H345A mutation.
- H354A mutation was introduced in ACE2 microbody proteins, in which the ACE2 ectodomain is fused to Fc domain 3 of the Ig heavy chain. This protein inhibits entry of SARS-CoV-2 spike protein pseudotyped virus and replication of live SARS-CoV-2 both in vitro and in mouse model (Tada et al., Cell Rep.; 2020, 33, 108528).
- WO 2021/217120 A2 discloses ACE2-Fc fusion proteins with mutations H345A, H345V, H345I or H345L, and R273A in the ACE2 domain; and with eliminated FcRy binding. Also disclosed is the use of a product comprising such a fusion protein for the prevention, or the reduction of severity of an infection by a coronavirus that binds to human ACE2 receptor.
- WO 2021/203098 A2 discloses ACE2-Fc fusion proteins with mutation H345L in the ACE2 domain, and with an Fc domain having one or more amino acid substitution(s). Said proteins are useful against ACE2-targeted viruses.
- WO 2021/183717 A1 discloses triple mutant ACE2-Fc fusion proteins, and discloses mutations H505L, H345A and R273L, separately.
- the proteins are used for the prevention and treatment of COVID-19 and other such virally induced diseases.
- the present invention provides a mutated recombinant fusion protein comprising a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, furthermore, the invention provides said mutated recombinant fusion protein for use in a method of treating infection diseases caused by a coronavirus.
- the invention further relates to a mutated recombinant fusion protein comprising a human ACE2 domain and a human IgG-Fc domain, wherein in comparison to the ACE2 domain of SEQ ID NO: 1 , the ACE2 domain of the mutated recombinant fusion protein comprises mutation (i) at positions R275, T373, H507; or (ii) at positions R275, H347, T373, H507, 1515; or (iii) at positions R275, H347, H507, 1515; or (iv) at position 1515; or (v) at positions T373, 1515; or (vi) at position H507; or (vii) at positions H507, 1515; or (viii) at position T373.
- the invention further relates to said mutated recombinant fusion protein, wherein a mutation (i) at position R275 is an exchange of R for L; (ii) at position H347 is an exchange of H for G, V, A, L or I; (iii) at position T373 is an exchange of T for F, Y or W; (iv) at position H507 is an exchange of H for G, V, A, L or I; and/or (v) at position 1515 is an exchange of I for T or S.
- the invention further relates to said mutated recombinant fusion protein, wherein a mutation (i) at position R275 is an exchange of R for L; (ii) at position H347 is an exchange of H for A; (iii) at position T373 is an exchange of T for F; (iv) at position H507 is an exchange of H for L; and/or (v) at position 1515 is an exchange of I for T.
- the invention further relates to any one of said mutated recombinant fusion proteins, wherein the human IgG-Fc domain of the mutated recombinant fusion protein is a human lgG1 -Fc domain.
- the invention further relates to said mutated recombinant fusion protein, wherein in comparison to the lgG1 -Fc region of SEQ ID NO: 1 , the lgG1-Fc domain of the mutated recombinant fusion protein comprises mutation at position N824.
- the invention further relates to said mutated recombinant fusion protein, wherein the mutation at position N824 is an exchange of N for G.
- the invention further relates to a mutated recombinant fusion protein, wherein the mutated recombinant fusion protein comprises a sequence selected from the group consisting of SEQ ID NOs: 13, 14, 15, 16, 21 , 22, 23 and 24.
- the invention further relates to a mutated recombinant fusion protein, wherein the mutated recombinant fusion protein has a sequence selected from the group consisting of SEQ ID NOs: 13, 14, 15, 16, 21 , 22, 23 and 24.
- the invention further relates to a mutated recombinant fusion protein, wherein the mutated recombinant fusion protein has a sequence as shown by SEQ ID NO: 15.
- the mutated recombinant fusion protein further comprises a signal peptide.
- the invention also relates to a mutated recombinant fusion protein comprising a human ACE2 domain and a human IgG-Fc domain, wherein in comparison to the ACE2 domain of SEQ ID NO: 1 , the ACE2 domain of the mutated recombinant fusion protein comprises mutation (i) at positions R275, T373, H507; or (ii) at positions R275, H347, T373, H507, 1515; or (iii) at positions R275, H347, H507, 1515; or (iv) at position 1515; or (v) at positions T373, 1515; or (vi) at position H507; or (vii) at positions H507, 1515; or (viii) at position T373, wherein the mutated recombinant fusion protein further comprises a signal peptide.
- the invention also relates to said mutated recombinant fusion protein, wherein a mutation (i) at position R275 is an exchange of R for L; (ii) at position H347 is an exchange of H for G, V, A, L or I; (iii) at position T373 is an exchange of T for F, Y or W; (iv) at position H507 is an exchange of H for G, V, A, L or I; and/or (v) at position 1515 is an exchange of I for T or S, wherein the mutated recombinant fusion protein further comprises a signal peptide.
- the invention also relates to said mutated recombinant fusion protein, wherein a mutation (i) at position R275 is an exchange of R for L; (ii) at position H347 is an exchange of H for A; (iii) at position T373 is an exchange of T for F; (iv) at position H507 is an exchange of H for L; and/or (v) at position 1515 is an exchange of I for T, wherein the mutated recombinant fusion protein further comprises a signal peptide.
- the invention further relates to any one of said mutated recombinant fusion proteins, wherein the human IgG-Fc domain of the mutated recombinant fusion protein is a human lgG1 -Fc domain, wherein the mutated recombinant fusion protein further comprises a signal peptide.
- the invention further relates to said mutated recombinant fusion protein, wherein in comparison to the lgG1 -Fc region of SEQ ID NO: 1 , the lgG1 -Fc domain of the mutated recombinant fusion protein comprises mutation at position N824, wherein the mutated recombinant fusion protein further comprises a signal peptide.
- the invention further relates to said mutated recombinant fusion protein, wherein the mutation at position N824 is an exchange of N for G, wherein the mutated recombinant fusion protein further comprises a signal peptide.
- the invention further relates to a mutated recombinant fusion protein, wherein the mutated recombinant fusion protein comprises a sequence selected from the group consisting of SEQ ID NOs: 13, 14, 15, 16, 21 , 22, 23 and 24, and wherein the mutated recombinant fusion protein further comprises a signal peptide.
- the invention further relates to a mutated recombinant fusion protein, wherein the mutated recombinant fusion protein comprises a sequence selected from the group consisting of SEQ ID NOs: 5, 7, 9, 11 , 17, 18, 19 and 20.
- the invention further relates to a mutated recombinant fusion protein, wherein the mutated recombinant fusion protein has a sequence selected from the group consisting of SEQ ID NOs: 5, 7, 9, 11 , 17, 18, 19 and 20.
- the invention further relates to a mutated recombinant fusion protein, wherein the mutated recombinant fusion protein has a sequence as shown by SEQ ID NO: 9.
- the invention relates to the mutated recombinant fusion protein as disclosed in the previous paragraphs, for use in a method of treating an infection disease caused by a coronavirus capable of binding ACE2, and optionally, wherein the infection disease is COVID-19.
- the invention relates to the mutated recombinant fusion protein as disclosed in the previous paragraphs, for use in a method of treating an infection disease caused by a coronavirus capable of binding ACE2, wherein the coronavirus capable of binding ACE2 is SARS-CoV-2, and optionally, wherein the infection disease is COVID-19.
- the invention also relates to a polynucleotide encoding a mutated recombinant fusion protein, wherein the polynucleotide comprises a sequence as shown in any one of SEQ ID NOs: 6, 8, 10, 12.
- the invention also relates to a polynucleotide encoding a mutated recombinant fusion protein, wherein the polynucleotide has a sequence as shown in any one of SEQ ID NOs: 6, 8, 10, 12.
- the invention further relates to a vector comprising said polynucleotide.
- the invention further relates to a host cell comprising said vector.
- the invention further relates to a CHO host cell comprising said vector.
- Figure 1 Proposed structure of the ACE2-Fc fusion protein: the extracellular domain of ACE2 is fused onto human immunoglobulin Fc domain. (Figure 1 is from Kruse, F1000Research; 2020, 9:72.)
- FIG. 2 Virus neutralization experiment of ACE2-Fc fusion protein against SARS- CoV-2 in Vero E6 cells. Cytopathic effects are only apparent at 1 :160 dilution of ACE2-Fc, and are marked at 1 :640.
- the micrographs are representative images of the micrographs taken of the wells during the virus neutralization experiment under phase contrast microscope.
- Figure 3 Peptide sequence of ACE2 (native)-Fc fusion protein according to SEQ ID NO: 1 ; functional domains of the protein (signal peptide, ACE2 extracellular domain, lgG1 Hinge and Fc region) are indicated.
- Figure 4 Peptide sequence of ACE2 (native)-Fc(N824G) fusion protein according to SEQ ID NO: 3; functional domains of the protein (signal peptide, ACE2 extracellular domain, lgG1 Hinge and Fc region) are indicated.
- Figure 5 Peptide sequence of ACE2 (H347A, H507L, R275L, T373F, I515T)- Fc(N824G) fusion protein according to SEQ ID NO: 5; functional domains of the protein (signal peptide, ACE2 extracellular domain, lgG1 Hinge and Fc region) are indicated.
- Figure 6 Peptide sequence of ACE2 (l515T)-Fc(N824G) fusion protein according to SEQ ID NO: 7; functional domains of the protein (signal peptide, ACE2 extracellular domain, lgG1 Hinge and Fc region) are indicated.
- Figure 7 Peptide sequence of ACE2 (H507L, R275L, T373F)-Fc(N824G) fusion protein according to SEQ ID NO: 9; functional domains of the protein (signal peptide, ACE2 extracellular domain, lgG1 Hinge and Fc region) are indicated.
- Figure 8 Peptide sequence of ACE2 (1515T, H507L, R275L, H347A)-Fc(N824G) fusion protein according to SEQ ID NO: 11 ; functional domains of the protein (signal peptide, ACE2 extracellular domain, lgG1 Hinge and Fc region) are indicated.
- Figure 9 Peptide sequence of ACE2 (H507L, R275L, T373F)-Fc(N824G) fusion protein according to SEQ ID NO: 15; functional domains of the protein (ACE2 extracellular domain, lgG1 Hinge and Fc region) are indicated.
- Figure 10 A bar graph based on data of column "Specific activity [AU/s/ml] Average" of Table 1 showing the results of the measurement of ACE2 activity of proteins of the present invention (Example 1 ).
- “Native” is ACE2(native)-Fc fusion protein
- “Fc” is mutant variant with mutation N824G
- “Fc+1x” is mutant variant with mutations 1515T, N824G
- “Fc+3x” is mutant variant with mutations R275L, T373F, H507L, N824G
- “Fc+4x” is mutant variant with mutations R275L, H347A, H507L, 1515T, N824G
- “Fc+5x” is mutant variant with mutations R275L, H347A, T373F, H507L, 1515T, N824G.
- Figure 11 Representative sensorgram of the native ACE2-Fc fusion protein, BLI assay.
- Figure 12 Representative sensorgram of the 3x mutant variant (mutant variant with mutations R275L, T373F, H507L and N824G in comparison to the ACE2 domain and lgG1 -Fc region of SEQ ID NO: 1 , respectively), BLI assay.
- Figure 13 Equilibrium binding (KD), native ACE2-Fc fusion protein and 3x mutant variant (mutant variant with mutations R275L, T373F, H507L, N824G), BLI assay. DETAILED DESCRIPTION OF THE INVENTION
- recombinant protein defines a protein that is produced artificially with the help of for example genetically modified microorganisms or cell cultures. Such organisms and cell cultures include, but are not limited to those, cells that express the desired mutated recombinant fusion protein.
- “Mutated” as used herein is related to biological mutations in the nucleotide sequence, including for example point mutations, insertions or deletions at specific positions. At mentioned positions, mutations include point mutations, insertions and deletions. The term “mutated” is also used in connection with peptides, referring to an alteration of an amino acid sequence, for example by deletion, insertion and/or substitution of one or more amino acids.
- neutralizing and “blocking” are used in an exchangeable way.
- neutralization refers to the complete or partial blocking of viruses or viral particles by binding the fusion protein to the viral S-protein.
- Coronaviruses in general use S-proteins for the attachment to the cell to be infected in order to gain access.
- S-proteins are spiky envelope proteins that are located on the outer surface of the virus and give it its typical shape. The spikes consist of a glycoprotein with which the virus is coupled to the host cell via the ACE2 receptor.
- SARS-CoV-2 has a very strong binding affinity to ACE2.
- a signal peptide is hereby determined as a short, 3 to 60 amino acid long peptide, which after translation determines the transport target of a protein within the cell.
- fragment crystallizable (Fc) region domains are regions of antibodies that allow interaction with cell surface receptors.
- the Fc region is composed of two identical protein fragments, derived from the second and third constant domains of the antibody's two heavy chains.
- IgM and IgE Fc regions contain three heavy chain constant domains in each polypeptide chain.
- IgG Fc domain interacts with the neonatal Fc receptor (FcRn) that protects this immunoglobulin isotype from intracellular degradation in capillary endothelial cells, or macrophages, dendritic cells, among other cell types and thus this mechanism provides long half-life for IgG molecules.
- FcRn neonatal Fc receptor
- antibody effector functions or effector functions can be for example the recruitment of effector cells of the immune system to bind viral particles or binding to a receptor, for example FcyR (IgG), FcsRI (IgE), FcaRI (IgA), FcpR (IgM) and FcbR (IgD).
- FcyR IgG
- FcsRI IgE
- FcaRI IgA
- FcpR IgM
- FcbR IgD
- treat refers to therapeutic or preventative measures described herein.
- the methods and uses of “treatment” employ administration of a mutated recombinant fusion peptide to a subject having an infection disease caused by a coronavirus.
- infection diseases caused by a coronavirus include, but are not limited to those: respiratory tract infections such as common cold diseases, characterized by fever, sore throat, runny nose, cough and headaches, Middle East Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS).
- respiratory tract infections such as common cold diseases, characterized by fever, sore throat, runny nose, cough and headaches
- MERS Middle East Respiratory Syndrome
- SARS Severe Acute Respiratory Syndrome
- Coronaviruses which are sought to be treated by the present invention, include all 4 genera of coronaviruses, namely: Alphacoronavirus, Betacoronavirus, Gammacoronavirus and Deltacoronavirus.
- Alphacoronavirus 1 Human coronavirus 229E, Human coronavirus NL63, Miniopterus bat coronavirus 1, Miniopterus bat coronavirus HKU8, Rhinolophus bat coronavirus HKU2, Scotophilus bat coronavirus 512, Betacoronavirus 1 (Bovine Coronavirus, Human coronavirus OC43), Hedgehog coronavirus 1, Human coronavirus HKU1, Middle East respiratory syndrome-related coronavirus, Murine coronavirus, Pipistrel I us bat coronavirus HKU5, Rousettus bat coronavirus HKU9, Severe acute respiratory syndrome-related coronavirus (SARS-CoV, SARS-CoV-2), Tylonycteris bat coronavirus HKU4, Avian coronavirus, Beluga whale coronavirus SW1, Bulbul coronavirus HKU11 and Porcine coronavirus HKU15.
- Betacoronavirus 1 Bovine Coronavirus, Human coronavirus OC43
- ACE2-Fc fusion protein appearing following a coronavirus infection, such as acute respiratory distress syndrome (ARDS), secondary hemophagocytic lym phohistiocytosis (sHLH) or bacterial infections such as pneumonia. This applies in particular to diseases that follow a CRS.
- ARDS acute respiratory distress syndrome
- sHLH secondary hemophagocytic lym phohistiocytosis
- bacterial infections such as pneumonia.
- the present invention comprises a mutated recombinant fusion peptide of ACE2 and/or fragments thereof and an Fc domain of human IgG (i.e. human IgG-Fc domain) and/or fragments thereof for binding viral proteins to prevent infection of a cell with said virus.
- Physiological ACE2 has an enzymatic activity, which, by hydrolysis of peptide bonds at the C-terminal end of angiotensin II, carried out by the peptidase domain (PD) of the enzyme, serves to generate angiotensin-(1-7), an important substance in the regulation of the renin-angiotensin-aldosterone system (RAAS).
- Mutations can reduce or completely eliminate this enzymatic activity of the peptidase domain (PD). While enzymatic activity of ACE2 is diminished, capability to bind viral spike-proteins (S-protein) is maintained, making it a powerful neutralizing agent against COVID-19 infections. Although these mutations influence the enzymatic activity of the protein, they do not affect the binding to the S-protein of the virus. For this reason, enzymatically inactive proteins can also be used for extracellular neutralization of the virus.
- the present invention relates to a mutated recombinant ACE2-Fc fusion peptide for effective neutralization of viral particles in infection diseases caused by a coronavirus.
- the invention disclosed herein offers effective therapy option(s) against corona viruses using enzymatically inactive ACE2 constructs for virus neutralization, wherein the mutated ACE2 domain is fused to an Fc domain, thereby increasing stability and half-life of the fusion protein in order to improve medical application.
- the present invention relates to a mutated recombinant fusion protein comprising a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515.
- the fusion protein of the invention comprises, apart from the mutations identified above, the ACE2 domain of SEQ ID NO:1 , but may comprise another IgG Fc domain.
- ACE2 activity was determined by performing an assay, which uses a specific quenched fluorescent substrate, as it was previously shown by Uri et al. in 2016 (J. Renin-Angiotensin- Aldosterone Syst.; 2016; 17(4): 1470320316668435).
- Uri et al. J. Renin-Angiotensin- Aldosterone Syst.; 2016; 17(4): 1470320316668435.
- purified recombinant ACE2 was used and the activity level was measured in a fluorescent microplate reader.
- the disclosed mutated recombinant fusion protein as disclosed herein can be used to neutralize SARS-CoV-2.
- SARS- CoV-2 from an anonymous patient sample was propagated using Vero E6 cells.
- the cytopathic effect (CPE) of the coronavirus was demonstrated by the destruction of the cell monolayer.
- Vero E6 cells were incubated with purified recombinant ACE2 fusion protein and diluted virus. Afterwards, the virus neutralizing effect of the ACE2-Fc fusion protein was evaluated by light microscopy. See Example 2 and Figure 2.
- Vero E6 cells are derived from an African green monkey (Chlorocebus sp.) and are routinely used in vaccine production for virus-related diseases. These experiments show a clear virus neutralization effect of the recombinant proteins of the invention.
- native ACE2-Fc fusion construct its amino acid sequence is known in the art (Kruse: Therapeutic strategies in an outbreak scenario to treat the novel coronavirus originating in Wuhan, China. F1000Research; 2020, 9:72), in addition, native ACE2-Fc fusion protein is commercially available. Also known in the art are preparation methods of mutant ACE2-Fc fusion proteins (see e.g. Liu et al.: Designed variants of ACE2-Fc that decouple anti-SARS-CoV-2 activities from unwanted cardiovascular effects. Int. J. Biol.
- SEQ ID NOs: 2, 4, 6, 8, 10 and 12 show nucleotide sequences. Representative nucleotide sequences and codons for ACE2-Fc fusion proteins of the present invention are shown in SEQ ID NOs: 6, 8, 10, 12, which in this order correspond to ACE2-Fc fusion proteins according to SEQ ID NOs: 5, 7, 9, 11.
- a polynucleotide encoding the protein according to the invention and a respective ACE2-Fc expression vector, such as a plasmid is constructed, then host cells, such as CHO (Chinese hamster ovary) cells, are transfected with the nucleic acid, such as DNA, construct coding ACE2-Fc. After selection the transfected pools are cultivated. Expressed ACE2-Fc fusion proteins are characterized, and at last, fusion proteins of the invention are purified from the supernatant of the cell cultures. SARS-CoV-2 has a very strong binding affinity to ACE2, which is exploited in the present invention.
- the mutated recombinant fusion peptide of the present invention is capable of binding S-proteins of coronaviruses, in order to allow proper neutralization.
- the interaction between an ACE2-Fc fusion protein and S-protein has been tested by BLI assay (Example 4, Figures 11 -13).
- the mutated recombinant fusion protein additionally further comprises a signal peptide.
- the signal peptide is a 3 to 60 amino acid long peptide.
- the signal peptide is between 10 and 30 amino acids, and in a more preferred embodiment, the signal peptide is between 10 and 25 amino acids.
- the signal peptide can be located at the N terminus of the protein, and in another embodiment, the signal peptide can be positioned at the C terminus of the protein.
- the mutated recombinant fusion protein does not encompass a signal peptide. In yet another embodiment, the mutated recombinant fusion protein encompasses a signal peptide that is different from the one disclosed in SEQ ID NO: 1 .
- the mutated recombinant fusion protein is modified.
- Modifications include, but are not limited to those, e.g. protein tags and posttranslational modifications. Examples for tags may be tagged fluorescent proteins, His-tags, Myc-tags, HA-tag, FLAG-tag, T7-tag and any other modification allowing the detection by standard biological methods.
- the recombinant polypeptide of the invention comprises an ACE2-domain.
- ACE2 mutations on mentioned positions impair enzymatic peptidase activity of ACE2 but, of importance, maintain all necessary binding affinities to Spikeproteins (S-proteins) of coronaviruses.
- S-proteins Spikeproteins
- the enzymatic activity of ACE2 can be impaired by 10%, 20%, 30%, 40% or about 50%, compared to the peptide variant of SEQ ID NO: 1. Included are also variants, where the complete enzymatic peptidase activity of ACE2 is abolished.
- the mutated recombinant fusion protein comprises an ACE2 domain, which is mutated to exhibit diminished enzymatic activity.
- the activity may be inhibited by any possible reduction. This includes activity reductions of 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, or even 90%. In another embodiment, the activity is completely absent.
- the mutated recombinant fusion peptide comprises an ACE2 domain, wherein the ACE2 domain is mutated in the peptidase domain, comprising amino acid 20 to amino acid 615, respectively.
- the recombinant polypeptide further comprises an Fc domain of human IgG.
- the present invention relates to a mutated recombinant fusion protein, comprising an ACE2 domain and an Fc domain.
- the Fc domain of the mutated recombinant fusion protein may be from any IgG, including lgG1 , lgG2, lgG3 and lgG4.
- the Fc domain of the mutated recombinant fusion protein is an lgG1 -Fc domain.
- the construct can either have antibody effector functions or not.
- the Fc domain can be non-mutated. In one embodiment, the Fc domain has the sequence of the Fc domain of SEQ ID NO: 1 . In another embodiment, the Fc domain can differ from the sequence of the Fc domain of SEQ ID NO: 1. Preferably, the sequence identity of the Fc domain is at least 70% homologue to the sequence of the Fc domain of SEQ ID NO:1. Other embodiments include Fc domains, wherein at least 80, 90 or 99% of the Fc domain is equal to the Fc domain of SEQ ID NO: 1 . In an embodiment, the Fc domain of the fusion protein has a sequence identity of at least 80%, 90% or 99% with the Fc domain of SEQ ID NO: 1 .
- the Fc domain can be modified by non-mutation modifications, to adjust its activity. Accordingly, in one embodiment the Fc domain can be glycosylated thereby maintaining all the effector functions of an antibody Fc region, such as recruiting the immune system to bound viral particles, or activating the complement cascade contributing to their elimination. In another embodiment the Fc domain is unglycosylated, resulting in a complete loss of immune activating functions. In those embodiments, the fused Fc domain only serves to increase the fusion protein’s half-life.
- the Fc domain can be mutated.
- the mutation is located at N824. More preferably, the mutation comprises an amino acid change from N to G, resulting in N824G, compared to SEQ ID NO: 1. Therefore, in one embodiment, the Fc domain comprises the sequence of the Fc domain of SEQ ID NO: 3. N824 is usually referred as N297 in literature and commonly used to adapt effector functions of an Fc domain.
- the Fc domain exhibits reduced effector functions, in particular reduced complement and Fc gamma receptor mediated (ADCC, ADCP) activation.
- ADCC complement and Fc gamma receptor mediated
- the Fc domain exhibits 10%, 20%, 30%, 40% or 50% reduced effector functions, compared to the wildtype Fc domain. Included are also variants, wherein the complete effector function of the Fc domain is abolished.
- Positions of the mutations according to the present invention as stated above refer to the following sequence representing a reference sequence (comprising the ACE2 extracellular domain, an lgG1 hinge and an lgG1 Fc region without mutations). Important sections (signal peptide, ACE2 extracellular domain and lgG1 hinge and lgG1 Fc region) are highlighted as described below the sequence.
- the mutated recombinant fusion protein comprises a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515.
- the mutation at one or more position(s) is selected from the group consisting of H347A, H507L, R275L, T373F and/or 1515T.
- the mutation at positions H347, H507, and R275 is an exchange of H for G, V, A, L, and I, or is an exchange of R for L, respectively.
- the mutation at position 1515 is an exchange for T or S.
- the exchange at position T373 is for F, Y or W.
- the mutated recombinant fusion peptide comprises a human ACE2 domain and an IgG-Fc domain, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s) selected from the group consisting of H347A, H507L, R275L, T373F and/or 1515T.
- the mutated recombinant fusion protein has the sequence(s) as shown in any of SEQ ID NO: 5, SEQ ID NO: 7, SEQ ID NO: 9 and SEQ ID NO: 11.
- the mutated recombinant fusion protein comprises a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, and wherein the Fc domain is an Fc domain of the human IgG 1 and is mutated at position N824, preferably wherein the mutation is N824G.
- the mutated recombinant fusion protein comprises a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, and in said mutated recombinant fusion protein the mutation at one or more position(s) is selected from the group consisting of H347A, H507L, R275L, T373F and/or 1515T, and wherein the Fc domain is an Fc domain of the human lgG1 and is mutated at position N824, preferably wherein the mutation is N824G.
- the mutated recombinant fusion protein can comprise the sequence as provided in SEQ ID NO: 5 and Figure 5.
- SEQ ID NO: 5 is, in comparison to SEQ ID NO: 1 , mutated at the following positions: 1515, H507, R275, T373, H347 and N824.
- the mutated recombinant fusion protein can comprise the sequence as provided in SEQ ID NO: 7 and Figure 6.
- SEQ ID NO: 7 is, in comparison to SEQ ID NO: 1 , mutated at the following positions: 1515 and N824.
- the mutated recombinant fusion protein can comprise the sequence as provided in SEQ ID NO: 9 and Figure 7.
- SEQ ID NO: 9 is, in comparison to SEQ ID NO: 1 , mutated at the following positions: H507L, R275L, T373F and N824.
- the mutated recombinant fusion protein can comprise the sequence of SEQ ID NO: 11 and Figure 8.
- SEQ ID NO: 11 is, in comparison to SEQ ID NO: 1 , mutated at the following positions: 1515, H507, R275, H347 and N824.
- the mutated recombinant fusion protein comprises a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, wherein the mutated recombinant fusion protein does not comprise a signal peptide.
- the mutated recombinant fusion protein comprises a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, wherein in said mutated recombinant fusion protein the mutation at one or more position(s) is selected from the group consisting of H347A, H507L, R275L, T373F and/or 1515T, and wherein the mutated recombinant fusion protein does not comprise a signal peptide.
- the mutated recombinant fusion protein comprises a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, and wherein the Fc domain is an Fc domain of the human IgG 1 and is mutated at position N824, preferably wherein the mutation is N824G, and wherein the mutated recombinant fusion protein does not comprise a signal peptide.
- the mutated recombinant fusion protein comprises a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, and in said mutated recombinant fusion protein the mutation at one or more position(s) is selected from the group consisting of H347A, H507L, R275L, T373F and/or 1515T, and wherein the Fc domain is an Fc domain of the human lgG1 and is mutated at position N824, preferably wherein the mutation is N824G, wherein the mutated recombinant fusion protein does not comprise a signal peptide.
- the mutated recombinant fusion protein has a sequence as shown in any of SEQ ID NO: 5, 7, 9, or 11 ; in a more preferred embodiment, said mutated recombinant fusion protein does not comprise a signal peptide (SEQ ID NO: 13, SEQ ID NO: 14, SEQ ID NO: 15, SEQ ID NO: 16).
- the mutated recombinant fusion protein can comprise the sequence of SEQ ID NO: 17.
- SEQ ID NO: 17 is, in comparison to SEQ ID NO: 1 , mutated at the following positions: H507, N824.
- the mutated recombinant fusion protein can comprise the sequence of SEQ ID NO: 18.
- SEQ ID NO: 18 is, in comparison to SEQ ID NO: 1 , mutated at the following positions: T373, N824.
- the mutated recombinant fusion protein can comprise the sequence of SEQ ID NO: 19.
- SEQ ID NO: 19 is, in comparison to SEQ ID NO: 1 , mutated at the following positions: T373, 1515, N824.
- the mutated recombinant fusion protein can comprise the sequence of SEQ ID NO: 20.
- SEQ ID NO: 20 is, in comparison to SEQ ID NO: 1 , mutated at the following positions: H507, 1515, N824.
- the mutated recombinant ACE2-Fc fusion protein has a sequence as shown in any one of SEQ ID NO: 17, SEQ ID NO: 18, SEQ ID NO: 19; SEQ ID NO: 20.
- said mutated recombinant fusion protein does not comprise a signal peptide (SEQ ID NO: 21 , SEQ ID NO: 22, SEQ ID NO: 23; SEQ ID NO: 24).
- the present invention also relates to a mutated recombinant fusion protein for use in a method of treating infection diseases caused by a coronavirus.
- the present invention relates to a mutated recombinant fusion protein for use in a method of treating infection diseases caused by a virus capable of binding ACE2.
- the coronavirus causing an infection disease is SARS- CoV-2 and the infection disease is COVID-19.
- the coronavirus causing an infection disease is SARS-CoV-2 including any variants thereof.
- the mutated recombinant fusion protein comprising a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, is for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-
- the mutated recombinant fusion protein comprising a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, wherein the mutation at one or more position(s) is selected from the group consisting
- the mutated recombinant fusion protein comprising a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, and wherein the Fc domain is an Fc domain of the human IgG 1 and is mutated at position N824, preferably wherein the mutation is N824G, is for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-19.
- the mutated recombinant fusion protein comprising a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, wherein the mutation at one or more position(s) is selected from the group consisting of H347A, H507L, R275L, T373F and/or 1515T, and wherein the Fc domain is an Fc domain of the human lgG1 and is mutated at position N824, preferably wherein the mutation is N824G, is for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-19.
- the mutated recombinant fusion protein wherein the Fc domain exhibits reduced effector functions, is for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV- 2 and wherein the infection disease is COVID-19.
- the present invention also relates to a mutated recombinant fusion protein having a sequence as shown in any of SEQ ID NO: 5, 7, 9, or 11 , for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-19.
- the mutated recombinant fusion protein comprising a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, and wherein said mutated recombinant fusion protein does not comprise a signal peptide, is for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-19.
- the mutated recombinant fusion protein comprising a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, wherein the mutation at one or more position(s) is selected from the group consisting of H347A, H507L, R275L, T373F and/or 1515T, and wherein said mutated recombinant fusion protein does not comprise a signal peptide, is for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-19.
- the mutated recombinant fusion protein comprising a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, and wherein the Fc domain is an Fc domain of the human IgG 1 and is mutated at position N824, preferably wherein the mutation is N824G, and wherein said mutated recombinant fusion protein does not comprise a signal peptide, is for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-19.
- the mutated recombinant fusion protein comprising a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, wherein the mutation at one or more position(s) is selected from the group consisting of H347A, H507L, R275L, T373F and/or 1515T, and wherein the Fc domain is an Fc domain of the human lgG1 and is mutated at position N824, preferably wherein the mutation is N824G, and wherein said mutated recombinant fusion protein does not comprise a signal peptide, is for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-19.
- the mutated recombinant fusion protein wherein the Fc domain exhibits reduced effector functions, and wherein said mutated recombinant fusion protein does not comprise a signal peptide, is for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-19.
- the mutated recombinant fusion protein having a sequence as shown in any of SEQ ID NO: 5, 7, 9, or 11 , wherein said mutated recombinant fusion protein does not comprise a signal peptide is for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-19.
- the mutated recombinant fusion protein having a sequence as shown in any of SEQ ID NOs: 13, 14, 15, 16, 17, 18, 19, 20, 21 , 22, 23, 24, is for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-19.
- the mutated recombinant fusion protein having a sequence as shown in SEQ ID NO: 9 or 15 is used in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-19.
- the disease Coronavirus-dependent disease 2019 (COVID-19) caused by the emerging virus SARS-CoV-2 is particularly influenced by the binding of the S-protein of SARS-CoV-2 to the membrane bound receptor ACE2.
- the fusion protein described in the present invention can also be used for the treatment of other diseases, in particular in diseases caused by the pathogens SARS-CoV and MERS.
- the methods and uses of treatment employ administration of a mutated recombinant fusion peptide to a subject having an infection disease caused by a coronavirus.
- Forms of administration for the infectious disease to be treated caused by coronavirus comprise both, local and systemic administration and include, but are not limited to those: intravenous administration, buccal administration, endobronchial administration, inhalative administration, intranasal administration, intraocular administration, intrapulmonal administration, oral administration.
- ACE2 angiotensin converting enzyme 2
- ACE2 activity for the detection of ACE2 activity, purified recombinant enzyme was used and the activity level was measured in a fluorescent microplate reader.
- Recombinant enzyme from supernatant of fed-batch harvest broth was diluted with its medium (CD FortiCHO medium, Gibco Cat.No: A1148301 ) by 4-20 fold (preparations with low enzymatic activity: Seq. ID NO: 03, 05, 07, 09, 11 ) or by 1 GO- 72, 900-fold (preparations with high enzymatic activity: Seq. ID No: 01 ).
- ACE2 activity measurement was performed using a specific quenched fluorescent substrate as it was previously shown in 2016 by Uri et al. (J. Renin-Angiotensin- Aldosterone Syst.; 2016; 17(4): 1470320316668435) described, performed with some modifications:
- the reaction mixture (200 pl) contained 10 pl diluted enzyme preparation, 25 pM ACE2-specific fluorescent substrate (7-methoxycoumarin-4- yl)acetyl-Ala-Pro-Lys(2,4-dinitrophenyl)-OH [Mca-APK(Dnp)] (custom synthesized by using Peptide 2.0 Software (Peptide 2.0 Inc.
- the unit of the activity is an arbitrary unit (AU), which is proportional with the substrate conversion.
- Nonspecific activity was determined by the addition of the ACE2 specific inhibitor MLN-4760 (Merck) at a final concentration of 1 pM. The non-specific activity was less than 10% and generally omitted from the evaluations.
- Table 1 the form of the results is as follows: the values are given in numericals written according to the English grammatical rules (using decimal point). Under the values given in English (e.g. 5.795 or 8155722), the output data in the original language, i.e. in Hungarian, are also given in brackets (i.e. with numericals written according to the Hungarian grammatical rules - using decimal comma, and using point for separating groups of hundreds within a number; e.g.: HU: 5,795 or HU: 8.155.722).
- Vero E6 ATCC® CRL-1586TM cells were maintained in DMEM (Lonza) supplemented with 10% heat inactivated fetal bovine serum (FBS; Gibco) and 1 % Penicillin/ Streptomycin (Lonza). Cells were kept in a 37°C, 5% CO2 incubator.
- hCoV- 19/Hungary/SRC_isolate_2/2020 accesion ID: EPI_ISL_483637 was used during experiments, originated form anonym human patient.
- TCID50 assay hCoV-19/Hungary/SRC_isolate_2/2020 viral stock was titrated using the TCID50 method. Briefly, serial 10-fold dilutions of hCoV-19/Hungary/SRC_isolate_2/2020 supernatant were inoculated (50 pl) on 80-90% confluent VeroE6 cells (40000 cells/well) in 96-well plates. Viral adsorption was allowed for 1 hour at 37°C. After washing cells with DMEM three times, cells were incubated for 3 days at 37°C in DMEM supplemented with 2% FBS (Gibco).
- Vero E6 cells were incubated with purified recombinant ACE2 fusion protein and diluted virus.
- Vero E6 cells were seeded into 96 well plates at 80-90% confluency (40000 cells/well) in DMEM supplemented with 10% heat-inactivated fetal bovine serum (Gibco US origin).
- Serial dilutions of the ACE2-Fc fusion protein (Seq-ID: 01 ) in DMEM from 1 :10 to 1 :640 were prepared.
- Virus stock was diluted to obtain 100 of the fifty-percent tissue culture infective dose (TCID50).
- TCID50 tissue culture infective dose
- the supernatant was then gently removed and replaced with 100 pl maintaining medium (DMEM: 2% FBS, 1 % Pen I Strep) and incubated for three days at 37°C. Afterwards, the virus neutralizing effect of the ACE2-Fc fusion protein was evaluated by light microscopy. The 100 pl supernatant was removed for nucleic acid extraction (Monarch, NEB). Droplet Digital PCR (ddPCR) (BIO-RAD) was performed from supernatant’s nucleic acid.
- ddPCR Droplet Digital PCR
- RT-ddPCR reaction mixture consisted of 5 pl of a ddPCR Supermix, 2 pl reverse transcriptase, 1 pl 300 mM DTT, 900 nM CoV specific primers and 250 nM probe, 1 pl of sample nucleic acid solution and nuclease-free H2O in a final volume of 22 pl.
- the entire reaction mixture was loaded into a disposable plastic cartridge (Bio-Rad, CA, USA) together with 70 pl of droplet generation oil for probes (Bio-Rad, CA, USA) and placed in the QX200 Droplet Generator (Bio-Rad, CA, USA).
- the droplets generated from each sample were transferred to a 96- well PCR plate (Bio-Rad CA, USA) and heat-sealed with PX1TM PCR Plate Sealer (Bio-Rad, CA, USA).
- PCR amplification was carried out on a C1000 TouchTM Thermal Cycler with 96-Deep Well Reaction Module (Bio-Rad, CA, USA) using a thermal profile of beginning at reverse transcription.
- the plate was loaded on the QX200 Droplet Reader (Bio-Rad, CA, USA) and the droplets from each well of the plate were read automatically. Positive droplets, containing amplification products, were partitioned from negative droplets by applying a fluorescence amplitude threshold in QuantaSoftTM analysis software (Bio-Rad, CA, USA). Quantification of the target molecule was presented as the number of copies per pl of the PCR mix.
- VeroE6 96-well plate
- VeroE6 cells 40,000 cells I well. Cells should be 80-90% confluent at the start of treatment.
- Dilution of ACE2-Fc material “neutralization”, infection of the cells; Dilution of ACE2-Fc material: half dilution from 1 :10 to 1 : 640 with a platen channel pipette, 5 replicates of each dilution:
- TCID50s there are 12,720,000 TCID50s in 1000 pl of virus stock (we know from a preliminary experiment). 100 TCID50 is in ⁇ 0.079 pl. For the whole 96-well plate, you need ⁇ 1.78 pl from the virus stock. Infection requires 50 pl I well diluted in DMEM. For 1 plate: 5000 pl DMEM + £ ⁇ 1 .78 pl virus.
- the recombinantly produced ACE2-Fc molecule contains the extracellular domain of ACE2 protein fused with hinge and Fc region of lgG1.
- Nucleotide sequences of mutant forms disclosed in the present application were designed and codon-optimized for CHO cells, where the submitted protein sequence was supplemented with the signal peptides of IgG heavy chain, an undefined 5’ UTR sequence, Kozak sequence, and the restriction recognition sites fit for the conventional T4 ligation based cloning work.
- Artificial nucleic acid sequence was synthesized by solid phase synthesis through the service of Thermo fisher, GeneArt.
- Construction of the expression vector was achieved through digestion both of the vector and the fragments with the same pair of restriction enzymes and then the ligation of the fragments into the correct positions of the expression vector using T4 ligase enzyme.
- CHO host cell line was thawed and passaged to recover the viability of the cell line. Cultivation of the host cell line was performed in CD FortiCHO (Thermo Fisher) and in BalanCD CHO Growth A (Irvine Scientific) supplemented with 4 mM L-glutamine (Thermo Fisher) in shake flasks (37°C, 85% humidity, 5% CO2, in a shake flask incubator (Kuhner)). Transfection of ACE2-Fc coding DNA constructs into CHO cells was performed by electroporation applying 4D Nucleofector system (Lonza) and its reagents (SF Cell Line 4D-Nucleofector, Lonza) as described by the manufacturer.
- Selection of the transfected cells was performed until the viability of the pools reached 90% meanwhile selection medium of the pools were changed in every 3-5 days.
- Selection medium contained 50 pM methionine-sulfoxide (MSX) without L-glutamine supplementation.
- MSX methionine-sulfoxide
- Single-cell isolation from the heterogenic pools were performed by limiting dilution technique or using VIPS device (Solentim) onto 96 well plates (Corning).
- Cell culture was clarified by centrifugation. The supernatant was loaded onto an affinity chromatography column containing protein A beads. The column was washed with 0.1 M sodium citrate pH 6.2 buffer and 1.5 M L-arginine, 0.1 M citric acid pH 4.2 buffer for ACE2-Fc elution.
- the elution sample was instantly neutralized with addition of 2 M Tris base.
- the purified ACE2-Fc fractions were analyzed using size exclusion HPLC and UV spectrometry to continue the purification of fractions with the best monomer ratio.
- the selected fractions were pooled and concentrated on a LIF/DF system.
- the concentrated pool was loaded on size exclusion column and eluted with 50 mM Na2PO4, 100 mM NaCI pH 6.8 to separate aggregates.
- the separated ACE2-Fc fractions were analyzed using size exclusion HPLC and UV spectrometry.
- the Octet platform is a label-free analytical technology by which we can obtain accurate information about rate of biomolecular complex formation and complex stability.
- BLI is an optical analytical technique that measures interference patterns between waves of light.
- White light is directed down the fiber-optic biosensor towards two interfaces separated by a thin layer at the tip of the fiber: a biocompatible layer on the surface of the tip, and an internal reference layer.
- Light reflects from each of the two layers, and the reflected beams interfere constructively or destructively at different wavelengths in the spectrum.
- target molecules bind to the 2-dimensional coated surface.
- This binding forms a molecular layer that increases in thickness as more target molecules bind to the surface.
- the spectral pattern of the reflected light therefore changes as a function of the optical thickness of the molecular layer. This spectral shift is monitored at the detector and reported on a sensorgram as a change in wavelength (nm shift). Monitoring the interference pattern in real time provides kinetic data on molecular interactions.
- the molecule which binds to the sensor’ s surface called ligand and the analyte is the molecule, which binds to the ligand.
- Assay buffer (20 mM HEPES, 150 mM NaCI, 0.02% (v/v) Tween20) was used to dilute the samples and references and to neutralize the biosensors. Glycine pH 1.5 (Cytiva) was used to regenerate the biosensors. We used Protein A biosensors (Sartorius) to attach the ACE2-Fc molecule to the biosensor’s surface. Then the analyte SARS-CoV-2 (COVID-19) S1 protein, His Tag (Aero Biosystems) was bound to the immobilized ACE2-Fc, which was the association phase. After 150 sec of association the next step was the dissociation for additional 150 sec. After evaluation the KD, kdis, k a values of ACE2-Fc were determined (by methods well-known in the art of enzyme kinetics) - S1 protein interaction, hence the binding strength between these molecules.
- FIG. 11 Representative sensorgram of the native ACE2-Fc fusion protein is shown in Figure 11
- Figure 12 representative sensorgram of the 3x mutant variant is shown in Figure 12.
- Figure 13 shows the respective equilibrium binding (KD) values on a diagram. The results clearly show the advantageous characteristics of the interaction between 3x mutant variant and S1 protein in comparison to the interaction between the native ACE2-Fc and S1 protein.
Landscapes
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Genetics & Genomics (AREA)
- Bioinformatics & Cheminformatics (AREA)
- Zoology (AREA)
- Wood Science & Technology (AREA)
- General Health & Medical Sciences (AREA)
- General Engineering & Computer Science (AREA)
- Biochemistry (AREA)
- Biomedical Technology (AREA)
- Molecular Biology (AREA)
- Medicinal Chemistry (AREA)
- Biotechnology (AREA)
- Microbiology (AREA)
- Immunology (AREA)
- Proteomics, Peptides & Aminoacids (AREA)
- Biophysics (AREA)
- Virology (AREA)
- Pharmacology & Pharmacy (AREA)
- Plant Pathology (AREA)
- Gastroenterology & Hepatology (AREA)
- Physics & Mathematics (AREA)
- Epidemiology (AREA)
- Animal Behavior & Ethology (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Vascular Medicine (AREA)
- Peptides Or Proteins (AREA)
Abstract
The invention relates to a mutated recombinant fusion protein comprising a human ACE2 domain and a human IgG-Fc domain, wherein in comparison to the ACE2 domain of SEQ ID NO: 1, the ACE2 domain of the mutated recombinant fusion protein comprises mutation (i) at positions R275, T373, H507; or (ii) at positions R275, H347, T373, H507, I515; or (iii) at positions R275, H347, H507, I515; or (iv) at position I515; or (v) at positions T373, I515; or (vi) at position H507; or (vii) at positions H507, I515; or (viii) at position T373. The invention also relates to said mutated recombinant fusion protein, further comprising a signal peptide. The invention further relates to said mutated recombinant fusion protein for use in a method of treating an infection disease caused by a coronavirus capable of binding ACE2. The invention also relates to a polynucleotide encoding said mutated recombinant fusion protein, and to a vector comprising said polynucleotide, as well as to a host cell comprising said vector.
Description
MUTATED RECOMBINANT ACE2-FC FUSION PROTEINS
FOR THE TREATMENT OF COVID-19 INFECTIONS
FIELD OF THE INVENTION
The present invention relates to mutated recombinant fusion proteins comprising mutated ACE2 domain(s) and/or fragments thereof and Fc domain(s) and their use for the treatment of COVID-19.
BACKGROUND OF THE INVENTION
In 2019, a new type of corona virus called SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) spread from China to the rest of the world and was declared a pandemic by the WHO (World Health Organization) in March, 2020. This virus is the third of its kind causing severe respiratory illness, following the pathogen SARS- CoV (severe acute respiratory syndrome coronavirus) and MERS-CoV (Middle East Respiratory Syndrome coronavirus), spreading in 2003 and 2012, respectively.
Currently, there is no specific therapy available for the treatment of the SARS-CoV- 2-related disease, which received the name COVID-19 (referring to coronavirus disease 2019). First approvals for vaccines are currently being granted in a fast-track process and will be produced for worldwide vaccination coverage in 2021 . Given the extremely rapid spreading of the disease, whose progression is however mild in most cases, there is an immense global urgency in the development of effective treatment strategies. Especially for severe courses of the disease, which occur in about 20% of patients and which cause fever and serious pneumonia, therapeutic and preventive options are of high importance (European Centre for Disease Prevention and Control, 2020). Risk factors are today considered to include male sex, smoking, hypertension, diabetes, obesity and preexisting cardiovascular disease; all of which are associated with an unfavorable prognosis for COVID-19 (Zou et al, N. Engl. J. Med.; 2020, 382, 1177-1179, Section “Findings”).
Symptoms of the newly emerged disease COVID-19 include, among others, dry cough and fever and general malaise. The most severe symptoms triggered by SARS-CoV-2 may also include cytokine release syndrome (CRS), which can be associated with various secondary diseases (e.g. pulmonary edema, acute respiratory distress syndrome (ARDS) or secondary hemophagocytic lym phohistiocytosis (sHLH)). According thereto, patients suffering COVID-19 may develop systemic hyper-inflammation, cause by increased levels of IL-2, II-7, II-6, granulocyte-macrophage colony-stimulating factor (GM-CSF), interferon-gamma- inducible protein 10 (IP-10), monocyte chemoattractant protein 1 (MCP-1 ), macrophage inflammatory protein 1-a (MIP-1a) and the tumor necrosis factor-alpha (TNFa) indicating CRS, as it was shown for example by Huang et al. (The Lancet; 2020, 395, 497-506)
All known variants of the newly appearing coronavirus allows itself to access the human body in a special way: SARS-CoV-2 binds to the cell surface receptor Angiotensin Converting Enzyme-2 (ACE2) in the body, in order to gain access to the attacked body cells allowing its reproduction. This receptor is particularly common in cardiopulmonary tissues, but it is also expressed in hematopoietic cells, such as monocytes and macrophages. The transmembrane protein natively cleaves angiotensin II within an enzymatic reaction. ACE2 thus plays an extremely important role in the renin-angiotensin-aldosterone system (RAAS) and thus in the regulation of fluid balance and blood pressure.
To date, there are no clearly effective drugs against COVID-19, and most patients are treated only on a symptom-specific basis. Accordingly, there is a strong medical need for the therapeutic approaches which allow the prevention, amelioration and the treatment of the disease and symptoms that are associated with inflammation of the respiratory tract and/or immunologically induced injury of the respiratory tract in a human subject. So far, various therapeutic approaches have been considered:
One therapeutic option is the development of receptor-binding domains (RBDs), in which a fragment of the viral protein blocks the cell surface receptor and thus prevents the virus from entering the cell. In 2004, Wong et al. (J. Biol. Chem.; 2004, 279, 3197-3201 ) showed that the RBD approach can be successfully used to block the ACE2 cell surface receptor and thus limit the access of SARS-CoV. Experiments
with monoclonal antibodies also showed a similar effect (Desmyter et al., Proc. Natl. Acad. Sci.; 2013, 110, E1371-E1379; Koch et al., Sci. Rep.; 2017, 7, 8390). However, the approach to the use of RBDs also has its limitations: this is shown by the fact that in most cases the body produces neutralizing antibodies against RBDs. In addition, the risks of using RBDs have not yet been described adequately. It is not yet known, whether there is a ratio of ACE2 receptors that are needed to be blocked in order to the viral infection to slow down or even halt. It is also questionable, what the density of ACE2 receptors is in certain organs and in the whole body. In addition, it is also possible that blocking ACE2 could ultimately worsen the clinical symptoms of infection by altering the normal physiological functions of ACE2.
Another strategy deals with the extracellular binding of viral proteins (Li et al., Nature; 2003, 426, 450-454) which are responsible for access to the cell even before the virus docks to the cell. In this case, soluble forms of the membrane-bound proteins are used to bind and block the virus in advance. It takes advantage of the strong affinity of the spike protein (S protein) to ACE2 to effectively prevent it from binding to the receptor. This technique is used in the present invention.
The generation of Fc-fusion proteins in order to improve half-life extension is commonly used in biomedical science, as long-circulating plasma proteins can result in reduced degradation.
ACE2-Fc fusion proteins were designed and tested by Liu et al. (Int. J. Biol. Macromol.; 2020, 165: 1626-1633). Nine mutants of ACE2-Fc (E145A, R273A, H345A, P346A, D368A, H374A, H378A, E402A, H505A) were studied, among them R273A, H378A and E402A were completely lack of ACE2 peptidase activity but maintained their binding capacity toward SARS-CoV-2 spike protein and inhibited the transduction of a pseudotyped reporter virus. According to the conclusions of the article, H378A and E402A mutations may potentially suffer protein instability problems.
Abolishment of peptidase activity together with high affinity binding to SARS-CoV-2 S protein is mentioned in connection with the H374 and H378 mutations of the ACE2 extracellular domain by Kruse (F1000Research; 2020, 9:72) citing Moore et al. (J Virol.; 2004, 10628-10635).
ACE-lg proteins containing the same mutations (H374, H378) neutralized virus pseudotyped with SARS-CoV or SARS-CoV-2 spike proteins in vitro (Lei et al., Nat. Comm.; 2020, 11 :2070).
A stepwise engineering approach to generate affinity optimized, enzymatically inactivated ACE2 variants able to tightly bind the RBD of the viral spike protein is described by Glasgow et al. (PNAS, 2020, 117, 45, 28046-55). The study came to the conclusion that H374N/H378N double mutation is unstable, therefore H345L mutation should be incorporated, too. The highest affinity clones contained N33D and H34S mutations and were derived from the K31 F/H34I/E35Q ACE2(614) variant, which bound to the RBD 170-fold more tightly than wild-type ACE2.
ACE2-Fc lgG1 fusion proteins are described in a preprint article of Iwanaga et al. (bioRxiv; 2020, Version 2.). Three mutants were engineered such as MDR503, MDR504 and MDR505. Among them MDR504 appeared to be the best candidate, which had greater binding to the SARS-CoV-2 RBD and spike protein and showed enhanced neutralization of virus in a Vero E6 cell plaque assay. Furthermore, MDR504 had similar serum stability as wild-type ACE2-Fc. A later version of the preprint article was published on 21st January 2022 (iScience 25, 103670), in which mutations are named: MDR503 has a R273A mutation, MDR504 has a H345A mutation and MDR505 has both R273A and H345A mutation.
H354A mutation was introduced in ACE2 microbody proteins, in which the ACE2 ectodomain is fused to Fc domain 3 of the Ig heavy chain. This protein inhibits entry of SARS-CoV-2 spike protein pseudotyped virus and replication of live SARS-CoV-2 both in vitro and in mouse model (Tada et al., Cell Rep.; 2020, 33, 108528).
Mutations at N824 in an Fc domain or fragments thereof are well known in the art (Wang et al., Protein & Cell; 2018, 9, 63-73). They are routinely used in immunologic science, as this specific mutation enables to switch off all effector functions of the Fc domain by depleting the ability to bind a receptor. Wang et al (Protein & Cell; 2018, 9, 63-73) summarize all known modifications concerning human IgG-s, which modifications influence the effector functions of a given antibody. As for the N297A, N297Q and N297G mutations described by Wang et al., the reduction of effector function is achieved by the mutation of asparagine in position 297 of Fc region.
WO 2021/217120 A2 discloses ACE2-Fc fusion proteins with mutations H345A, H345V, H345I or H345L, and R273A in the ACE2 domain; and with eliminated FcRy binding. Also disclosed is the use of a product comprising such a fusion protein for the prevention, or the reduction of severity of an infection by a coronavirus that binds to human ACE2 receptor.
WO 2021/203098 A2 discloses ACE2-Fc fusion proteins with mutation H345L in the ACE2 domain, and with an Fc domain having one or more amino acid substitution(s). Said proteins are useful against ACE2-targeted viruses.
WO 2021/183717 A1 discloses triple mutant ACE2-Fc fusion proteins, and discloses mutations H505L, H345A and R273L, separately. The proteins are used for the prevention and treatment of COVID-19 and other such virally induced diseases.
However, there is still a need in the art for improved ACE2-Fc fusion proteins for the prevention and treatment of an infection disease caused by a coronavirus capable of binding ACE2, especially, caused by any variants of SARS-CoV-2.
SUMMARY OF THE INVENTION
The present invention provides a mutated recombinant fusion protein comprising a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, furthermore, the invention provides said mutated recombinant fusion protein for use in a method of treating infection diseases caused by a coronavirus.
The invention further relates to a mutated recombinant fusion protein comprising a human ACE2 domain and a human IgG-Fc domain, wherein in comparison to the ACE2 domain of SEQ ID NO: 1 , the ACE2 domain of the mutated recombinant fusion protein comprises mutation (i) at positions R275, T373, H507; or (ii) at positions R275, H347, T373, H507, 1515; or (iii) at positions R275, H347, H507, 1515; or (iv) at position 1515; or (v) at positions T373, 1515; or (vi) at position H507; or (vii) at positions H507, 1515; or (viii) at position T373. The invention further relates to said mutated recombinant fusion protein, wherein a mutation (i) at position R275 is an exchange of R for L; (ii) at position H347 is an exchange of H for G, V, A, L or I; (iii)
at position T373 is an exchange of T for F, Y or W; (iv) at position H507 is an exchange of H for G, V, A, L or I; and/or (v) at position 1515 is an exchange of I for T or S. The invention further relates to said mutated recombinant fusion protein, wherein a mutation (i) at position R275 is an exchange of R for L; (ii) at position H347 is an exchange of H for A; (iii) at position T373 is an exchange of T for F; (iv) at position H507 is an exchange of H for L; and/or (v) at position 1515 is an exchange of I for T. The invention further relates to any one of said mutated recombinant fusion proteins, wherein the human IgG-Fc domain of the mutated recombinant fusion protein is a human lgG1 -Fc domain. The invention further relates to said mutated recombinant fusion protein, wherein in comparison to the lgG1 -Fc region of SEQ ID NO: 1 , the lgG1-Fc domain of the mutated recombinant fusion protein comprises mutation at position N824. The invention further relates to said mutated recombinant fusion protein, wherein the mutation at position N824 is an exchange of N for G. The invention further relates to a mutated recombinant fusion protein, wherein the mutated recombinant fusion protein comprises a sequence selected from the group consisting of SEQ ID NOs: 13, 14, 15, 16, 21 , 22, 23 and 24. The invention further relates to a mutated recombinant fusion protein, wherein the mutated recombinant fusion protein has a sequence selected from the group consisting of SEQ ID NOs: 13, 14, 15, 16, 21 , 22, 23 and 24. The invention further relates to a mutated recombinant fusion protein, wherein the mutated recombinant fusion protein has a sequence as shown by SEQ ID NO: 15.
In another aspect of the invention, the mutated recombinant fusion protein further comprises a signal peptide. The invention also relates to a mutated recombinant fusion protein comprising a human ACE2 domain and a human IgG-Fc domain, wherein in comparison to the ACE2 domain of SEQ ID NO: 1 , the ACE2 domain of the mutated recombinant fusion protein comprises mutation (i) at positions R275, T373, H507; or (ii) at positions R275, H347, T373, H507, 1515; or (iii) at positions R275, H347, H507, 1515; or (iv) at position 1515; or (v) at positions T373, 1515; or (vi) at position H507; or (vii) at positions H507, 1515; or (viii) at position T373, wherein the mutated recombinant fusion protein further comprises a signal peptide. The invention also relates to said mutated recombinant fusion protein, wherein a mutation (i) at position R275 is an exchange of R for L; (ii) at position H347 is an exchange of H for G, V, A, L or I; (iii) at position T373 is an exchange of T for F, Y or W; (iv) at
position H507 is an exchange of H for G, V, A, L or I; and/or (v) at position 1515 is an exchange of I for T or S, wherein the mutated recombinant fusion protein further comprises a signal peptide. The invention also relates to said mutated recombinant fusion protein, wherein a mutation (i) at position R275 is an exchange of R for L; (ii) at position H347 is an exchange of H for A; (iii) at position T373 is an exchange of T for F; (iv) at position H507 is an exchange of H for L; and/or (v) at position 1515 is an exchange of I for T, wherein the mutated recombinant fusion protein further comprises a signal peptide. The invention further relates to any one of said mutated recombinant fusion proteins, wherein the human IgG-Fc domain of the mutated recombinant fusion protein is a human lgG1 -Fc domain, wherein the mutated recombinant fusion protein further comprises a signal peptide. The invention further relates to said mutated recombinant fusion protein, wherein in comparison to the lgG1 -Fc region of SEQ ID NO: 1 , the lgG1 -Fc domain of the mutated recombinant fusion protein comprises mutation at position N824, wherein the mutated recombinant fusion protein further comprises a signal peptide. The invention further relates to said mutated recombinant fusion protein, wherein the mutation at position N824 is an exchange of N for G, wherein the mutated recombinant fusion protein further comprises a signal peptide. The invention further relates to a mutated recombinant fusion protein, wherein the mutated recombinant fusion protein comprises a sequence selected from the group consisting of SEQ ID NOs: 13, 14, 15, 16, 21 , 22, 23 and 24, and wherein the mutated recombinant fusion protein further comprises a signal peptide. The invention further relates to a mutated recombinant fusion protein, wherein the mutated recombinant fusion protein comprises a sequence selected from the group consisting of SEQ ID NOs: 5, 7, 9, 11 , 17, 18, 19 and 20. The invention further relates to a mutated recombinant fusion protein, wherein the mutated recombinant fusion protein has a sequence selected from the group consisting of SEQ ID NOs: 5, 7, 9, 11 , 17, 18, 19 and 20. The invention further relates to a mutated recombinant fusion protein, wherein the mutated recombinant fusion protein has a sequence as shown by SEQ ID NO: 9.
In a further aspect, the invention relates to the mutated recombinant fusion protein as disclosed in the previous paragraphs, for use in a method of treating an infection disease caused by a coronavirus capable of binding ACE2, and optionally, wherein the infection disease is COVID-19. In a further aspect, the invention relates to the
mutated recombinant fusion protein as disclosed in the previous paragraphs, for use in a method of treating an infection disease caused by a coronavirus capable of binding ACE2, wherein the coronavirus capable of binding ACE2 is SARS-CoV-2, and optionally, wherein the infection disease is COVID-19.
The invention also relates to a polynucleotide encoding a mutated recombinant fusion protein, wherein the polynucleotide comprises a sequence as shown in any one of SEQ ID NOs: 6, 8, 10, 12. The invention also relates to a polynucleotide encoding a mutated recombinant fusion protein, wherein the polynucleotide has a sequence as shown in any one of SEQ ID NOs: 6, 8, 10, 12. The invention further relates to a vector comprising said polynucleotide. The invention further relates to a host cell comprising said vector. The invention further relates to a CHO host cell comprising said vector.
BRIEF DESCRIPTION OF THE FIGURES
Figure 1 : Proposed structure of the ACE2-Fc fusion protein: the extracellular domain of ACE2 is fused onto human immunoglobulin Fc domain. (Figure 1 is from Kruse, F1000Research; 2020, 9:72.)
Figure 2: Virus neutralization experiment of ACE2-Fc fusion protein against SARS- CoV-2 in Vero E6 cells. Cytopathic effects are only apparent at 1 :160 dilution of ACE2-Fc, and are marked at 1 :640. The micrographs are representative images of the micrographs taken of the wells during the virus neutralization experiment under phase contrast microscope.
Figure 3: Peptide sequence of ACE2 (native)-Fc fusion protein according to SEQ ID NO: 1 ; functional domains of the protein (signal peptide, ACE2 extracellular domain, lgG1 Hinge and Fc region) are indicated.
Figure 4: Peptide sequence of ACE2 (native)-Fc(N824G) fusion protein according to SEQ ID NO: 3; functional domains of the protein (signal peptide, ACE2 extracellular domain, lgG1 Hinge and Fc region) are indicated.
Figure 5: Peptide sequence of ACE2 (H347A, H507L, R275L, T373F, I515T)- Fc(N824G) fusion protein according to SEQ ID NO: 5; functional domains of the
protein (signal peptide, ACE2 extracellular domain, lgG1 Hinge and Fc region) are indicated.
Figure 6: Peptide sequence of ACE2 (l515T)-Fc(N824G) fusion protein according to SEQ ID NO: 7; functional domains of the protein (signal peptide, ACE2 extracellular domain, lgG1 Hinge and Fc region) are indicated.
Figure 7: Peptide sequence of ACE2 (H507L, R275L, T373F)-Fc(N824G) fusion protein according to SEQ ID NO: 9; functional domains of the protein (signal peptide, ACE2 extracellular domain, lgG1 Hinge and Fc region) are indicated.
Figure 8: Peptide sequence of ACE2 (1515T, H507L, R275L, H347A)-Fc(N824G) fusion protein according to SEQ ID NO: 11 ; functional domains of the protein (signal peptide, ACE2 extracellular domain, lgG1 Hinge and Fc region) are indicated.
Figure 9: Peptide sequence of ACE2 (H507L, R275L, T373F)-Fc(N824G) fusion protein according to SEQ ID NO: 15; functional domains of the protein (ACE2 extracellular domain, lgG1 Hinge and Fc region) are indicated.
Figure 10: A bar graph based on data of column "Specific activity [AU/s/ml] Average" of Table 1 showing the results of the measurement of ACE2 activity of proteins of the present invention (Example 1 ). Legend: "Native" is ACE2(native)-Fc fusion protein; "Fc" is mutant variant with mutation N824G; "Fc+1x" is mutant variant with mutations 1515T, N824G; "Fc+3x" is mutant variant with mutations R275L, T373F, H507L, N824G; "Fc+4x" is mutant variant with mutations R275L, H347A, H507L, 1515T, N824G; "Fc+5x" is mutant variant with mutations R275L, H347A, T373F, H507L, 1515T, N824G.
Figure 11 : Representative sensorgram of the native ACE2-Fc fusion protein, BLI assay.
Figure 12: Representative sensorgram of the 3x mutant variant (mutant variant with mutations R275L, T373F, H507L and N824G in comparison to the ACE2 domain and lgG1 -Fc region of SEQ ID NO: 1 , respectively), BLI assay.
Figure 13: Equilibrium binding (KD), native ACE2-Fc fusion protein and 3x mutant variant (mutant variant with mutations R275L, T373F, H507L, N824G), BLI assay.
DETAILED DESCRIPTION OF THE INVENTION
Definitions
As used herein, “recombinant protein” defines a protein that is produced artificially with the help of for example genetically modified microorganisms or cell cultures. Such organisms and cell cultures include, but are not limited to those, cells that express the desired mutated recombinant fusion protein.
“Mutated” as used herein is related to biological mutations in the nucleotide sequence, including for example point mutations, insertions or deletions at specific positions. At mentioned positions, mutations include point mutations, insertions and deletions. The term "mutated" is also used in connection with peptides, referring to an alteration of an amino acid sequence, for example by deletion, insertion and/or substitution of one or more amino acids.
In the context of the present invention, the terms “neutralizing” and “blocking” are used in an exchangeable way. The term "neutralization" as used here refers to the complete or partial blocking of viruses or viral particles by binding the fusion protein to the viral S-protein. Coronaviruses in general use S-proteins for the attachment to the cell to be infected in order to gain access. S-proteins are spiky envelope proteins that are located on the outer surface of the virus and give it its typical shape. The spikes consist of a glycoprotein with which the virus is coupled to the host cell via the ACE2 receptor. SARS-CoV-2 has a very strong binding affinity to ACE2.
A signal peptide is hereby determined as a short, 3 to 60 amino acid long peptide, which after translation determines the transport target of a protein within the cell.
As used herein, fragment crystallizable (Fc) region domains are regions of antibodies that allow interaction with cell surface receptors. In IgG, IgA and IgD antibody isotypes, the Fc region is composed of two identical protein fragments, derived from the second and third constant domains of the antibody's two heavy chains. IgM and IgE Fc regions contain three heavy chain constant domains in each polypeptide chain. IgG Fc domain interacts with the neonatal Fc receptor (FcRn) that protects this immunoglobulin isotype from intracellular degradation in capillary endothelial cells, or macrophages, dendritic cells, among other cell types and thus this mechanism provides long half-life for IgG molecules.
As used herein, antibody effector functions or effector functions, allowing antibodies to act in a large number of mechanisms, can be for example the recruitment of effector cells of the immune system to bind viral particles or binding to a receptor, for example FcyR (IgG), FcsRI (IgE), FcaRI (IgA), FcpR (IgM) and FcbR (IgD).
As used herein, the term “treat,” “treating,” and “treatment” refer to therapeutic or preventative measures described herein. The methods and uses of “treatment” employ administration of a mutated recombinant fusion peptide to a subject having an infection disease caused by a coronavirus.
As used herein, infection diseases caused by a coronavirus include, but are not limited to those: respiratory tract infections such as common cold diseases, characterized by fever, sore throat, runny nose, cough and headaches, Middle East Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS). Coronaviruses, which are sought to be treated by the present invention, include all 4 genera of coronaviruses, namely: Alphacoronavirus, Betacoronavirus, Gammacoronavirus and Deltacoronavirus. Included are especially Alphacoronavirus 1, Human coronavirus 229E, Human coronavirus NL63, Miniopterus bat coronavirus 1, Miniopterus bat coronavirus HKU8, Rhinolophus bat coronavirus HKU2, Scotophilus bat coronavirus 512, Betacoronavirus 1 (Bovine Coronavirus, Human coronavirus OC43), Hedgehog coronavirus 1, Human coronavirus HKU1, Middle East respiratory syndrome-related coronavirus, Murine coronavirus, Pipistrel I us bat coronavirus HKU5, Rousettus bat coronavirus HKU9, Severe acute respiratory syndrome-related coronavirus (SARS-CoV, SARS-CoV-2), Tylonycteris bat coronavirus HKU4, Avian coronavirus, Beluga whale coronavirus SW1, Bulbul coronavirus HKU11 and Porcine coronavirus HKU15. Also included herein are secondary diseases, appearing following a coronavirus infection, such as acute respiratory distress syndrome (ARDS), secondary hemophagocytic lym phohistiocytosis (sHLH) or bacterial infections such as pneumonia. This applies in particular to diseases that follow a CRS.
ACE2-Fc fusion protein according to the invention
The present invention comprises a mutated recombinant fusion peptide of ACE2 and/or fragments thereof and an Fc domain of human IgG (i.e. human IgG-Fc domain) and/or fragments thereof for binding viral proteins to prevent infection of a cell with said virus. Physiological ACE2 has an enzymatic activity, which, by hydrolysis of peptide bonds at the C-terminal end of angiotensin II, carried out by the peptidase domain (PD) of the enzyme, serves to generate angiotensin-(1-7), an important substance in the regulation of the renin-angiotensin-aldosterone system (RAAS). Mutations can reduce or completely eliminate this enzymatic activity of the peptidase domain (PD). While enzymatic activity of ACE2 is diminished, capability to bind viral spike-proteins (S-protein) is maintained, making it a powerful neutralizing agent against COVID-19 infections. Although these mutations influence the enzymatic activity of the protein, they do not affect the binding to the S-protein of the virus. For this reason, enzymatically inactive proteins can also be used for extracellular neutralization of the virus. The present invention relates to a mutated recombinant ACE2-Fc fusion peptide for effective neutralization of viral particles in infection diseases caused by a coronavirus. The invention disclosed herein offers effective therapy option(s) against corona viruses using enzymatically inactive ACE2 constructs for virus neutralization, wherein the mutated ACE2 domain is fused to an Fc domain, thereby increasing stability and half-life of the fusion protein in order to improve medical application.
Accordingly, in a first aspect, the present invention relates to a mutated recombinant fusion protein comprising a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515.
Consequently, the fusion protein of the invention comprises, apart from the mutations identified above, the ACE2 domain of SEQ ID NO:1 , but may comprise another IgG Fc domain.
As it is shown in Example 1 , mutations in the ACE2 domain as disclosed in the present invention can reduce ACE2 activity as it is illustrated in Table 1 . ACE2 activity was determined by performing an assay, which uses a specific quenched fluorescent
substrate, as it was previously shown by Uri et al. in 2016 (J. Renin-Angiotensin- Aldosterone Syst.; 2016; 17(4): 1470320316668435). For the detection of ACE2 activity, purified recombinant ACE2 was used and the activity level was measured in a fluorescent microplate reader.
Furthermore, the disclosed mutated recombinant fusion protein as disclosed herein can be used to neutralize SARS-CoV-2. For testing the virus neutralization, SARS- CoV-2 from an anonymous patient sample was propagated using Vero E6 cells. The cytopathic effect (CPE) of the coronavirus was demonstrated by the destruction of the cell monolayer. For demonstrating the neutralization effect of the fusion protein, Vero E6 cells were incubated with purified recombinant ACE2 fusion protein and diluted virus. Afterwards, the virus neutralizing effect of the ACE2-Fc fusion protein was evaluated by light microscopy. See Example 2 and Figure 2. Vero E6 cells are derived from an African green monkey (Chlorocebus sp.) and are routinely used in vaccine production for virus-related diseases. These experiments show a clear virus neutralization effect of the recombinant proteins of the invention.
As for the native ACE2-Fc fusion construct, its amino acid sequence is known in the art (Kruse: Therapeutic strategies in an outbreak scenario to treat the novel coronavirus originating in Wuhan, China. F1000Research; 2020, 9:72), in addition, native ACE2-Fc fusion protein is commercially available. Also known in the art are preparation methods of mutant ACE2-Fc fusion proteins (see e.g. Liu et al.: Designed variants of ACE2-Fc that decouple anti-SARS-CoV-2 activities from unwanted cardiovascular effects. Int. J. Biol. Macromol.; 2020, 165: 1626-1633; Iwanaga et al.: Novel ACE2-lgG1 fusions with improved in vitro and in vivo activity against SARS- CoV-2. bioRxiv; 2020, Version 2.). In example 3, preparation method of the recombinant ACE2-Fc fusion proteins of the present invention is disclosed. SEQ ID NOs: 2, 4, 6, 8, 10 and 12 show nucleotide sequences. Representative nucleotide sequences and codons for ACE2-Fc fusion proteins of the present invention are shown in SEQ ID NOs: 6, 8, 10, 12, which in this order correspond to ACE2-Fc fusion proteins according to SEQ ID NOs: 5, 7, 9, 11. For the preparation of a mutated recombinant ACE2-Fc fusion protein of the invention a polynucleotide encoding the protein according to the invention and a respective ACE2-Fc expression vector, such as a plasmid, is constructed, then host cells, such as CHO (Chinese hamster ovary)
cells, are transfected with the nucleic acid, such as DNA, construct coding ACE2-Fc. After selection the transfected pools are cultivated. Expressed ACE2-Fc fusion proteins are characterized, and at last, fusion proteins of the invention are purified from the supernatant of the cell cultures. SARS-CoV-2 has a very strong binding affinity to ACE2, which is exploited in the present invention. Therefore, in one embodiment, the mutated recombinant fusion peptide of the present invention is capable of binding S-proteins of coronaviruses, in order to allow proper neutralization. The interaction between an ACE2-Fc fusion protein and S-protein has been tested by BLI assay (Example 4, Figures 11 -13).
In a further embodiment, the mutated recombinant fusion protein additionally further comprises a signal peptide. In an embodiment, the signal peptide is a 3 to 60 amino acid long peptide. In a preferred embodiment, the signal peptide is between 10 and 30 amino acids, and in a more preferred embodiment, the signal peptide is between 10 and 25 amino acids. In one embodiment the signal peptide can be located at the N terminus of the protein, and in another embodiment, the signal peptide can be positioned at the C terminus of the protein.
In another embodiment of the present invention, the mutated recombinant fusion protein does not encompass a signal peptide. In yet another embodiment, the mutated recombinant fusion protein encompasses a signal peptide that is different from the one disclosed in SEQ ID NO: 1 .
In yet another embodiment, the mutated recombinant fusion protein is modified. Modifications include, but are not limited to those, e.g. protein tags and posttranslational modifications. Examples for tags may be tagged fluorescent proteins, His-tags, Myc-tags, HA-tag, FLAG-tag, T7-tag and any other modification allowing the detection by standard biological methods.
As discussed above, the recombinant polypeptide of the invention comprises an ACE2-domain. ACE2 mutations on mentioned positions impair enzymatic peptidase activity of ACE2 but, of importance, maintain all necessary binding affinities to Spikeproteins (S-proteins) of coronaviruses. By mutating ACE2 domains, the enzymatic activity of ACE2 can be impaired by 10%, 20%, 30%, 40% or about 50%, compared to the peptide variant of SEQ ID NO: 1. Included are also variants, where the complete enzymatic peptidase activity of ACE2 is abolished.
Therefore, in one embodiment, the mutated recombinant fusion protein comprises an ACE2 domain, which is mutated to exhibit diminished enzymatic activity. In particular, the activity may be inhibited by any possible reduction. This includes activity reductions of 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, or even 90%. In another embodiment, the activity is completely absent.
In still another embodiment the mutated recombinant fusion peptide comprises an ACE2 domain, wherein the ACE2 domain is mutated in the peptidase domain, comprising amino acid 20 to amino acid 615, respectively.
The recombinant polypeptide further comprises an Fc domain of human IgG. As stated above, the present invention relates to a mutated recombinant fusion protein, comprising an ACE2 domain and an Fc domain.
In the context of the present invention, the Fc domain of the mutated recombinant fusion protein may be from any IgG, including lgG1 , lgG2, lgG3 and lgG4.
In a preferred embodiment of the present invention, the Fc domain of the mutated recombinant fusion protein is an lgG1 -Fc domain.
Depending on the structure of the Fc domain, the construct can either have antibody effector functions or not.
In one embodiment, the Fc domain can be non-mutated. In one embodiment, the Fc domain has the sequence of the Fc domain of SEQ ID NO: 1 . In another embodiment, the Fc domain can differ from the sequence of the Fc domain of SEQ ID NO: 1. Preferably, the sequence identity of the Fc domain is at least 70% homologue to the sequence of the Fc domain of SEQ ID NO:1. Other embodiments include Fc domains, wherein at least 80, 90 or 99% of the Fc domain is equal to the Fc domain of SEQ ID NO: 1 . In an embodiment, the Fc domain of the fusion protein has a sequence identity of at least 80%, 90% or 99% with the Fc domain of SEQ ID NO: 1 .
Furthermore, in another embodiment of the present invention, the Fc domain can be modified by non-mutation modifications, to adjust its activity. Accordingly, in one embodiment the Fc domain can be glycosylated thereby maintaining all the effector functions of an antibody Fc region, such as recruiting the immune system to bound viral particles, or activating the complement cascade contributing to their elimination. In another embodiment the Fc domain is unglycosylated, resulting in a complete loss
of immune activating functions. In those embodiments, the fused Fc domain only serves to increase the fusion protein’s half-life.
In still another embodiment, the Fc domain can be mutated. Preferably, the mutation is located at N824. More preferably, the mutation comprises an amino acid change from N to G, resulting in N824G, compared to SEQ ID NO: 1. Therefore, in one embodiment, the Fc domain comprises the sequence of the Fc domain of SEQ ID NO: 3. N824 is usually referred as N297 in literature and commonly used to adapt effector functions of an Fc domain.
In yet another embodiment, the Fc domain exhibits reduced effector functions, in particular reduced complement and Fc gamma receptor mediated (ADCC, ADCP) activation.
In preferred embodiments, the Fc domain exhibits 10%, 20%, 30%, 40% or 50% reduced effector functions, compared to the wildtype Fc domain. Included are also variants, wherein the complete effector function of the Fc domain is abolished.
Positions of the mutations according to the present invention as stated above refer to the following sequence representing a reference sequence (comprising the ACE2 extracellular domain, an lgG1 hinge and an lgG1 Fc region without mutations). Important sections (signal peptide, ACE2 extracellular domain and lgG1 hinge and lgG1 Fc region) are highlighted as described below the sequence.
SEQ ID NO: 1
MDWIWRILFLVGAATGAHSQSTIEEQAKTFLDKFNHEAEDLFYQSSLASWNYNTNI TEENVQNMNNAGDKWSAFLKEQSTLAQMYPLQEIQNLTVKLQLQALQQNGSSVL SEDKSKRLNTILNTMSTIYSTGKVCNPDNPQECLLLEPGLNEIMANSLDYNERLWA WESWRSEVGKQLRPLYEEYWLKNEMARANHYEDYGDYWRGDYEVNGVDGYD YSRGQLIEDVEHTFEEIKPLYEHLHAYVRAKLMNAYPSYISPIGCLPAHLLGDMWG RFWTNLYSLTVPFGQKPNIDVTDAMVDQAWDAQRIFKEAEKFFVSVGLPNMTQG FWENSMLTDPGNVQKAVCHPTAWDLGKGDFRILMCTKVTMDDFLTAHHEMGHIQ YDMAYAAQPFLLRNGANEGFHEAVGEIMSLSAATPKHLKSIGLLSPDFQEDNETEI NFLLKQALTIVGTLPFTYMLEKWRWMVFKGEIPKDQWMKKWWEMKREIVGWEP VPHDETYCDPASLFHVSNDYSFIRYYTRTLYQFQFQEALCQAAKHEGPLHKCDIS NSTEAGQKLFNMLRLGKSEPWTLALENWGAKNMNVRPLLNYFEPLFTWLKDQN
KNSFVGWSTDWSPYADQSIKVRISLKSALGDKAYEWNDNEMYLFRSSVAYAMRQ YFLKVKNQMILFGEEDVRVANLKPRISFNFFVTAPKNVSDIIPRTEVEKAIRMSRSRI NDAFRLNDNSLEFLGIQPTLGPPNQPPVSEP SCD THTCPPCB4PELLGGPSVE LFPPKPKDTLMISRTPE VTC VVVD VSHEDPEVKFNWYVDG VE VHNAKTKPREEQ Y NSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLP PSRDELTKNQ VSLTCL VKGFYPSDIA VEWESNGQPENNYKTTPPVLDSDGSFFLY SKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK
Signal peptide
ACE2 extracellular domain lgG1 Hinge and lgG1 Fc region
In a preferred embodiment, the mutated recombinant fusion protein comprises a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515. In a further preferred embodiment, in said mutated recombinant fusion protein the mutation at one or more position(s) is selected from the group consisting of H347A, H507L, R275L, T373F and/or 1515T.
In a preferred embodiment of the invention, the mutation at positions H347, H507, and R275 is an exchange of H for G, V, A, L, and I, or is an exchange of R for L, respectively.
In another preferred embodiment, the mutation at position 1515 is an exchange for T or S. In a further embodiment, the exchange at position T373 is for F, Y or W. In a further embodiment of the present invention, the mutated recombinant fusion peptide comprises a human ACE2 domain and an IgG-Fc domain, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s) selected from the group consisting of H347A, H507L, R275L, T373F and/or 1515T.
In another embodiment, the mutated recombinant fusion protein has the sequence(s) as shown in any of SEQ ID NO: 5, SEQ ID NO: 7, SEQ ID NO: 9 and SEQ ID NO: 11.
In another preferred embodiment, the mutated recombinant fusion protein comprises a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2
domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, and wherein the Fc domain is an Fc domain of the human IgG 1 and is mutated at position N824, preferably wherein the mutation is N824G.
In another preferred embodiment, the mutated recombinant fusion protein comprises a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, and in said mutated recombinant fusion protein the mutation at one or more position(s) is selected from the group consisting of H347A, H507L, R275L, T373F and/or 1515T, and wherein the Fc domain is an Fc domain of the human lgG1 and is mutated at position N824, preferably wherein the mutation is N824G.
Accordingly, in one embodiment, the mutated recombinant fusion protein can comprise the sequence as provided in SEQ ID NO: 5 and Figure 5. SEQ ID NO: 5 is, in comparison to SEQ ID NO: 1 , mutated at the following positions: 1515, H507, R275, T373, H347 and N824.
Furthermore, in another embodiment, the mutated recombinant fusion protein can comprise the sequence as provided in SEQ ID NO: 7 and Figure 6. SEQ ID NO: 7 is, in comparison to SEQ ID NO: 1 , mutated at the following positions: 1515 and N824.
Moreover, in another embodiment, the mutated recombinant fusion protein can comprise the sequence as provided in SEQ ID NO: 9 and Figure 7. SEQ ID NO: 9 is, in comparison to SEQ ID NO: 1 , mutated at the following positions: H507L, R275L, T373F and N824.
Additionally, in still another embodiment, the mutated recombinant fusion protein can comprise the sequence of SEQ ID NO: 11 and Figure 8. SEQ ID NO: 11 is, in comparison to SEQ ID NO: 1 , mutated at the following positions: 1515, H507, R275, H347 and N824.
In a preferred embodiment, the mutated recombinant fusion protein comprises a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s),
selected from the group consisting of H347, H507, R275, T373 and/or 1515, wherein the mutated recombinant fusion protein does not comprise a signal peptide.
In a further preferred embodiment, the mutated recombinant fusion protein comprises a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, wherein in said mutated recombinant fusion protein the mutation at one or more position(s) is selected from the group consisting of H347A, H507L, R275L, T373F and/or 1515T, and wherein the mutated recombinant fusion protein does not comprise a signal peptide.
In another preferred embodiment, the mutated recombinant fusion protein comprises a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, and wherein the Fc domain is an Fc domain of the human IgG 1 and is mutated at position N824, preferably wherein the mutation is N824G, and wherein the mutated recombinant fusion protein does not comprise a signal peptide.
In another preferred embodiment, the mutated recombinant fusion protein comprises a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, and in said mutated recombinant fusion protein the mutation at one or more position(s) is selected from the group consisting of H347A, H507L, R275L, T373F and/or 1515T, and wherein the Fc domain is an Fc domain of the human lgG1 and is mutated at position N824, preferably wherein the mutation is N824G, wherein the mutated recombinant fusion protein does not comprise a signal peptide.
In a preferred embodiment, the mutated recombinant fusion protein has a sequence as shown in any of SEQ ID NO: 5, 7, 9, or 11 ; in a more preferred embodiment, said mutated recombinant fusion protein does not comprise a signal peptide (SEQ ID NO: 13, SEQ ID NO: 14, SEQ ID NO: 15, SEQ ID NO: 16).
In another embodiment, the mutated recombinant fusion protein can comprise the sequence of SEQ ID NO: 17. SEQ ID NO: 17 is, in comparison to SEQ ID NO: 1 , mutated at the following positions: H507, N824. In another embodiment, the mutated recombinant fusion protein can comprise the sequence of SEQ ID NO: 18. SEQ ID NO: 18 is, in comparison to SEQ ID NO: 1 , mutated at the following positions: T373, N824. In another embodiment, the mutated recombinant fusion protein can comprise the sequence of SEQ ID NO: 19. SEQ ID NO: 19 is, in comparison to SEQ ID NO: 1 , mutated at the following positions: T373, 1515, N824. In another embodiment, the mutated recombinant fusion protein can comprise the sequence of SEQ ID NO: 20. SEQ ID NO: 20 is, in comparison to SEQ ID NO: 1 , mutated at the following positions: H507, 1515, N824. In another embodiment, the mutated recombinant ACE2-Fc fusion protein has a sequence as shown in any one of SEQ ID NO: 17, SEQ ID NO: 18, SEQ ID NO: 19; SEQ ID NO: 20. In a further embodiment, said mutated recombinant fusion protein does not comprise a signal peptide (SEQ ID NO: 21 , SEQ ID NO: 22, SEQ ID NO: 23; SEQ ID NO: 24).
The present invention also relates to a mutated recombinant fusion protein for use in a method of treating infection diseases caused by a coronavirus.
Furthermore, the present invention relates to a mutated recombinant fusion protein for use in a method of treating infection diseases caused by a virus capable of binding ACE2.
In a preferred embodiment, the coronavirus causing an infection disease is SARS- CoV-2 and the infection disease is COVID-19. In a further preferred embodiment, the coronavirus causing an infection disease is SARS-CoV-2 including any variants thereof.
In a preferred embodiment, the mutated recombinant fusion protein comprising a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, is for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-
In a preferred embodiment, the mutated recombinant fusion protein comprising a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, wherein the mutation at one or more position(s) is selected from the group consisting of H347A, H507L, R275L, T373F and/or 1515T, is for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-19.
In a preferred embodiment, the mutated recombinant fusion protein comprising a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, and wherein the Fc domain is an Fc domain of the human IgG 1 and is mutated at position N824, preferably wherein the mutation is N824G, is for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-19.
In a preferred embodiment, the mutated recombinant fusion protein comprising a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, wherein the mutation at one or more position(s) is selected from the group consisting of H347A, H507L, R275L, T373F and/or 1515T, and wherein the Fc domain is an Fc domain of the human lgG1 and is mutated at position N824, preferably wherein the mutation is N824G, is for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-19.
In a preferred embodiment, the mutated recombinant fusion protein, wherein the Fc domain exhibits reduced effector functions, is for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV- 2 and wherein the infection disease is COVID-19.
The present invention also relates to a mutated recombinant fusion protein having a sequence as shown in any of SEQ ID NO: 5, 7, 9, or 11 , for use in a method of
treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-19.
In a preferred embodiment, the mutated recombinant fusion protein comprising a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, and wherein said mutated recombinant fusion protein does not comprise a signal peptide, is for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-19.
In a preferred embodiment, the mutated recombinant fusion protein comprising a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, wherein the mutation at one or more position(s) is selected from the group consisting of H347A, H507L, R275L, T373F and/or 1515T, and wherein said mutated recombinant fusion protein does not comprise a signal peptide, is for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-19.
In a preferred embodiment, the mutated recombinant fusion protein comprising a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, and wherein the Fc domain is an Fc domain of the human IgG 1 and is mutated at position N824, preferably wherein the mutation is N824G, and wherein said mutated recombinant fusion protein does not comprise a signal peptide, is for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-19.
In a preferred embodiment, the mutated recombinant fusion protein comprising a human ACE2 domain and an Fc domain of human IgG, wherein the human ACE2 domain in comparison to SEQ ID NO: 1 is mutated at one or more position(s), selected from the group consisting of H347, H507, R275, T373 and/or 1515, wherein
the mutation at one or more position(s) is selected from the group consisting of H347A, H507L, R275L, T373F and/or 1515T, and wherein the Fc domain is an Fc domain of the human lgG1 and is mutated at position N824, preferably wherein the mutation is N824G, and wherein said mutated recombinant fusion protein does not comprise a signal peptide, is for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-19.
In a preferred embodiment, the mutated recombinant fusion protein, wherein the Fc domain exhibits reduced effector functions, and wherein said mutated recombinant fusion protein does not comprise a signal peptide, is for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-19.
In a preferred embodiment, the mutated recombinant fusion protein having a sequence as shown in any of SEQ ID NO: 5, 7, 9, or 11 , wherein said mutated recombinant fusion protein does not comprise a signal peptide, is for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-19.
In a preferred embodiment, the mutated recombinant fusion protein having a sequence as shown in any of SEQ ID NOs: 13, 14, 15, 16, 17, 18, 19, 20, 21 , 22, 23, 24, is for use in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-19.
Preferably, the mutated recombinant fusion protein having a sequence as shown in SEQ ID NO: 9 or 15 is used in a method of treating infection diseases caused by a coronavirus, optionally, wherein the coronavirus is SARS-CoV-2 and wherein the infection disease is COVID-19.
The disease Coronavirus-dependent disease 2019 (COVID-19) caused by the emerging virus SARS-CoV-2 is particularly influenced by the binding of the S-protein of SARS-CoV-2 to the membrane bound receptor ACE2. In other forms, the fusion protein described in the present invention can also be used for the treatment of other diseases, in particular in diseases caused by the pathogens SARS-CoV and MERS.
The methods and uses of treatment employ administration of a mutated recombinant fusion peptide to a subject having an infection disease caused by a coronavirus. Forms of administration for the infectious disease to be treated caused by coronavirus comprise both, local and systemic administration and include, but are not limited to those: intravenous administration, buccal administration, endobronchial administration, inhalative administration, intranasal administration, intraocular administration, intrapulmonal administration, oral administration.
The invention is further described with the help of the following examples and figures, which are intended to illustrate, but not to limit the invention.
EXAMPLES
EXAMPLE 1
Measurement of recombinantly expressed angiotensin converting enzyme 2 (ACE2) activity
In this example, for the detection of ACE2 activity, purified recombinant enzyme was used and the activity level was measured in a fluorescent microplate reader.
Recombinant enzyme from supernatant of fed-batch harvest broth was diluted with its medium (CD FortiCHO medium, Gibco Cat.No: A1148301 ) by 4-20 fold (preparations with low enzymatic activity: Seq. ID NO: 03, 05, 07, 09, 11 ) or by 1 GO- 72, 900-fold (preparations with high enzymatic activity: Seq. ID No: 01 ).
ACE2 activity measurement was performed using a specific quenched fluorescent substrate as it was previously shown in 2016 by Uri et al. (J. Renin-Angiotensin- Aldosterone Syst.; 2016; 17(4): 1470320316668435) described, performed with some modifications: The reaction mixture (200 pl) contained 10 pl diluted enzyme preparation, 25 pM ACE2-specific fluorescent substrate (7-methoxycoumarin-4- yl)acetyl-Ala-Pro-Lys(2,4-dinitrophenyl)-OH [Mca-APK(Dnp)] (custom synthesized by using Peptide 2.0 Software (Peptide 2.0 Inc. Chantilly, VA, US) in a buffer composed of 500 mM NaCI, 100 pM ZnC , 75 mM TRIS HCI, pH 6.5. Activity was measured in black 96 well plates in a fluorescent microplate reader (Clariostar).
ACE2 activity was monitored by measuring the increase in fluorescence (excitation wavelength: 320 nm, emission wavelength: 405 nm) in a kinetic assay. The increase in fluorescence was plotted as a function of reaction time and fitted with a linear regression.
ACE2 activity was calculated by the equation: ACE2 activity=S*D, where S is the rate of increase in fluorescence intensity (Slope of the linear regression) and D is the dilution of the sample. Slope values were accepted when fits resulted in r2 >0.95. The unit of the activity is an arbitrary unit (AU), which is proportional with the substrate conversion.
Nonspecific activity was determined by the addition of the ACE2 specific inhibitor MLN-4760 (Merck) at a final concentration of 1 pM. The non-specific activity was less than 10% and generally omitted from the evaluations.
Results
The results of the measurement of enzymatic activity of the ACE2 domain of mutated recombinant fusion proteins of the invention are summarized in Table 1 and in Fig. 10. According to these results, advantageously it has been found that mutations in the ACE2 domain as disclosed in the present invention reduce ACE2 activity in a great extent. As for mutant variant Fc+3x, it can be seen in Table 1 that the specific activity (average) of said ACE2-Fc mutant variant is 0.03% of the native form.
In Table 1 the form of the results is as follows: the values are given in numericals written according to the English grammatical rules (using decimal point). Under the values given in English (e.g. 5.795 or 8155722), the output data in the original language, i.e. in Hungarian, are also given in brackets (i.e. with numericals written according to the Hungarian grammatical rules - using decimal comma, and using point for separating groups of hundreds within a number; e.g.: HU: 5,795 or HU: 8.155.722).
Table 1 - Specific Activity and Titer of the Mutants - begins on next page
The average specific activity (AU/s/ml) of mutant variants tested in this measurement are also shown by a bar graph in Fig. 10. Especially, Fc+3x (mutant variant with mutations R275L, T373F, H507L, N824G), Fc+4x (mutant variant with mutations R275L, H347A, H507L, 1515T, N824G) and Fc+5x (mutant variant with mutations R275L, H347A, T373F, H507L, 1515T, N824G) exhibit a greatly reduced ACE2 activity.
EXAMPLE 2
Virus Neutralization Assay
1 . Cells and Virus
Vero E6 (ATCC® CRL-1586™) cells were maintained in DMEM (Lonza) supplemented with 10% heat inactivated fetal bovine serum (FBS; Gibco) and 1 % Penicillin/ Streptomycin (Lonza). Cells were kept in a 37°C, 5% CO2 incubator. hCoV- 19/Hungary/SRC_isolate_2/2020 (Accession ID: EPI_ISL_483637) was used during experiments, originated form anonym human patient.
2. Virus Propagation
Patient sample was inoculated on VeroE6 cells at 37°C, 5% CO2 incubator. The absorption period was 30 minutes with shaking every 10 minutes. Cells were observed for cytopathic effect (CPE) every 24 hours. The virus was passaged three times before collected, clarified, aliquoted and stored at -80°C.
3. TCID50 assay hCoV-19/Hungary/SRC_isolate_2/2020 viral stock was titrated using the TCID50 method. Briefly, serial 10-fold dilutions of hCoV-19/Hungary/SRC_isolate_2/2020 supernatant were inoculated (50 pl) on 80-90% confluent VeroE6 cells (40000 cells/well) in 96-well plates. Viral adsorption was allowed for 1 hour at 37°C. After washing cells with DMEM three times, cells were incubated for 3 days at 37°C in DMEM supplemented with 2% FBS (Gibco). The percentage of infected wells was observed with microscopy and recorded for each virus dilution then results were used to mathematically calculate a TCID50 result with the Spearman-Karber method. From the results obtained, 100TCID50 was calculated and used in further experiments.
4. Neutralization assay
For demonstrating the neutralization effect of the fusion protein, Vero E6 cells were incubated with purified recombinant ACE2 fusion protein and diluted virus.
Vero E6 cells were seeded into 96 well plates at 80-90% confluency (40000 cells/well) in DMEM supplemented with 10% heat-inactivated fetal bovine serum (Gibco US origin). Serial dilutions of the ACE2-Fc fusion protein (Seq-ID: 01 ) in DMEM from 1 :10 to 1 :640 were prepared. Virus stock was diluted to obtain 100 of the fifty-percent tissue culture infective dose (TCID50). For the infection 50 pl of an appropriate dilution of the ACE2-Fc fusion protein together with 50 pl of the 100TCID50 was then added to VeroE6 cells. The plates were then incubated for 1 hour at 37°C and several times agitated.
The supernatant was then gently removed and replaced with 100 pl maintaining medium (DMEM: 2% FBS, 1 % Pen I Strep) and incubated for three days at 37°C. Afterwards, the virus neutralizing effect of the ACE2-Fc fusion protein was evaluated by light microscopy. The 100 pl supernatant was removed for nucleic acid extraction (Monarch, NEB). Droplet Digital PCR (ddPCR) (BIO-RAD) was performed from supernatant’s nucleic acid.
5. Droplet Digital PCR
QX200 Droplet Digital PCR system (Bio-Rad, CA, USA) was used to determine virus copy number decrease triggered by ACE2-Fc fusion protein from supernatants. One- Step RT-ddPCR advanced kit for probes (Bio-Rad, CA, USA) was used in our experiments. The RT-ddPCR reaction mixture consisted of 5 pl of a ddPCR Supermix, 2 pl reverse transcriptase, 1 pl 300 mM DTT, 900 nM CoV specific primers and 250 nM probe, 1 pl of sample nucleic acid solution and nuclease-free H2O in a final volume of 22 pl. The entire reaction mixture was loaded into a disposable plastic cartridge (Bio-Rad, CA, USA) together with 70 pl of droplet generation oil for probes (Bio-Rad, CA, USA) and placed in the QX200 Droplet Generator (Bio-Rad, CA, USA). After processing, the droplets generated from each sample were transferred to a 96- well PCR plate (Bio-Rad CA, USA) and heat-sealed with PX1TM PCR Plate Sealer (Bio-Rad, CA, USA). PCR amplification was carried out on a C1000 TouchTM Thermal Cycler with 96-Deep Well Reaction Module (Bio-Rad, CA, USA) using a
thermal profile of beginning at reverse transcription. After amplification, the plate was loaded on the QX200 Droplet Reader (Bio-Rad, CA, USA) and the droplets from each well of the plate were read automatically. Positive droplets, containing amplification products, were partitioned from negative droplets by applying a fluorescence amplitude threshold in QuantaSoftTM analysis software (Bio-Rad, CA, USA). Quantification of the target molecule was presented as the number of copies per pl of the PCR mix.
Practical implementation
1. Using a 96-well plate (VeroE6); VeroE6 cells: 40,000 cells I well. Cells should be 80-90% confluent at the start of treatment.
2. Dilution of ACE2-Fc material, “neutralization”, infection of the cells; Dilution of ACE2-Fc material: half dilution from 1 :10 to 1 : 640 with a platen channel pipette, 5 replicates of each dilution:
■ Concentrated ACE2-Fc material
■ 1 :10 - 495 pl DMEM + 55 pl ACE2-Fc material (measure every 100 pl, of which take 50 pl)
■ 1 :20 - 50 pl DMEM + 50 pl 1 : 10 ACE2-Fc material
■ 1 :40 - 50 pl DMEM + 50 pl 1 :20 ACE2-Fc material
■ 1 :80 - 50 pl DMEM + 50 pl 1 :40 ACE2-Fc material
■ 1 : 160 - 50 pl DMEM + 50 pl 1 :80 ACE2-Fc material
■ 1 :320 - 50 pl DMEM + 50 pl 1 :160 ACE2-Fc material
■ 1 :640 - 50 pl DMEM + 50 pl 1 :320 ACE2-Fc material
3. Add 100 TCID50 viruses (dilute virus from stock):
There are 12,720,000 TCID50s in 1000 pl of virus stock (we know from a preliminary experiment). 100 TCID50 is in ~0.079 pl. For the whole 96-well plate, you need ~ 1.78 pl from the virus stock. Infection requires 50 pl I well diluted in DMEM. For 1 plate: 5000 pl DMEM + £ ~ 1 .78 pl virus.
4. Neutralization
50 pl ACE2-Fc material (at appropriate dilution) I well + 50 pl 100 TCID50 virus I well; Incubation: 1 hour at 37 °C (neutralization). Meanwhile, move every 10 minutes.
5. Infection of cells: Measurement of neutralized virus (100 l I well) incubated for 1 hour on cells.
6. Incubation: 30 min at 37 °C. Meanwhile, move every 10 minutes. After incubation, cells were aspirated and 100 pl of maintainer (DMEM: 2% FBS, 1 % Pen I Strep) was added. Incubation 3 days 37 °C
7. Microscopic reading of the result (whether the cells were infected in the given well). Nucleic acid extraction from supernatant for ddP.
Results
The results are shown by Figure 2. Cytopathic effects of the coronavirus (demonstrated by the destruction of the cell monolayer) are only apparent at 1 :160 dilution of ACE2-Fc, and are marked at 1 :640. The experiments show a clear virus neutralization effect of the recombinant protein.
On the basis of the results of a preliminary virus neutralization experiment carried out on ACE2-Fc mutant variant with mutations R275L, T373F, H507L and N824G in comparison to the ACE2 domain and IgG 1 -Fc region of SEQ ID NO: 1 , respectively, a virus neutralization effect of said ACE2-Fc mutant variant is expected.
EXAMPLE 3
Preparation of the mutated recombinant ACE2-Fc fusion proteins of the invention
Materials and methods
Construction of ACE2-Fc expression plasmids
Structurally, the recombinantly produced ACE2-Fc molecule contains the extracellular domain of ACE2 protein fused with hinge and Fc region of lgG1. Nucleotide sequences of mutant forms disclosed in the present application (including mutants listed in the Sequence Listing) were designed and codon-optimized for CHO cells, where the submitted protein sequence was supplemented with the signal peptides of IgG heavy chain, an undefined 5’ UTR sequence, Kozak sequence, and the restriction recognition sites fit for the conventional T4 ligation based cloning work.
Artificial nucleic acid sequence was synthesized by solid phase synthesis through the service of Thermo fisher, GeneArt.
Construction of the expression vector was achieved through digestion both of the vector and the fragments with the same pair of restriction enzymes and then the ligation of the fragments into the correct positions of the expression vector using T4 ligase enzyme.
Sequence verification of the final plasmids was performed using complete restriction analysis and DNA sequencing of the coding subunits to ensure the correctness of the construct. Before transfection, plasmids were linearized with controlled restriction digestion followed by ethanol precipitation providing sterility.
Cultivation of Chinese hamster ovary (CHO) cell lines
CHO host cell line was thawed and passaged to recover the viability of the cell line. Cultivation of the host cell line was performed in CD FortiCHO (Thermo Fisher) and in BalanCD CHO Growth A (Irvine Scientific) supplemented with 4 mM L-glutamine (Thermo Fisher) in shake flasks (37°C, 85% humidity, 5% CO2, in a shake flask incubator (Kuhner)). Transfection of ACE2-Fc coding DNA constructs into CHO cells was performed by electroporation applying 4D Nucleofector system (Lonza) and its reagents (SF Cell Line 4D-Nucleofector, Lonza) as described by the manufacturer. Selection of the transfected cells was performed until the viability of the pools reached 90% meanwhile selection medium of the pools were changed in every 3-5 days. Selection medium contained 50 pM methionine-sulfoxide (MSX) without L-glutamine supplementation. Single-cell isolation from the heterogenic pools were performed by limiting dilution technique or using VIPS device (Solentim) onto 96 well plates (Corning).
Batch cultivation of the transfected pools and expanded monoclones was performed in selection medium in shake flasks as detailed before, while fed-batch cultivation of the cell lines was performed in unsupplemented CD FortiCHO or BalanCD CHO Growth A media with 5 VA/% feed (Efficient Feed C+, Thermo Fisher, Feed 4, Irvine Scientific, respectively) addition every two days from day 3 and D-glucose
supplementation. Cell free supernatant of the cultures were used for expressed ACE2-Fc protein characterization.
Protein Purification from supernatant
Cell culture was clarified by centrifugation. The supernatant was loaded onto an affinity chromatography column containing protein A beads. The column was washed with 0.1 M sodium citrate pH 6.2 buffer and 1.5 M L-arginine, 0.1 M citric acid pH 4.2 buffer for ACE2-Fc elution.
The elution sample was instantly neutralized with addition of 2 M Tris base. The purified ACE2-Fc fractions were analyzed using size exclusion HPLC and UV spectrometry to continue the purification of fractions with the best monomer ratio. The selected fractions were pooled and concentrated on a LIF/DF system.
As a second purification step the concentrated pool was loaded on size exclusion column and eluted with 50 mM Na2PO4, 100 mM NaCI pH 6.8 to separate aggregates. The separated ACE2-Fc fractions were analyzed using size exclusion HPLC and UV spectrometry.
After pooling of fractions with the best quality, the selected fractions were pooled and concentrated again on UF/DF system.
Final ACE2-Fc concentration was 1 .0 mg/ml in the final composition.
EXAMPLE 4
Analytical characterization
The BLI method
Direct measurement of biomolecular interactions plays an important role in biotherapeutic drug discovery and development. The Octet platform is a label-free analytical technology by which we can obtain accurate information about rate of biomolecular complex formation and complex stability. BLI is an optical analytical technique that measures interference patterns between waves of light. White light is directed down the fiber-optic biosensor towards two interfaces separated by a thin
layer at the tip of the fiber: a biocompatible layer on the surface of the tip, and an internal reference layer. Light reflects from each of the two layers, and the reflected beams interfere constructively or destructively at different wavelengths in the spectrum. When the tip of a biosensor is dipped into a sample, target molecules bind to the 2-dimensional coated surface. This binding forms a molecular layer that increases in thickness as more target molecules bind to the surface. As the thickness at the tip increases, creating a shift in the interference patterns of the reflected light. The spectral pattern of the reflected light therefore changes as a function of the optical thickness of the molecular layer. This spectral shift is monitored at the detector and reported on a sensorgram as a change in wavelength (nm shift). Monitoring the interference pattern in real time provides kinetic data on molecular interactions.
In the BLI experiments the molecule which binds to the sensor’s surface called ligand and the analyte is the molecule, which binds to the ligand.
BLI assay
Assay buffer (20 mM HEPES, 150 mM NaCI, 0.02% (v/v) Tween20) was used to dilute the samples and references and to neutralize the biosensors. Glycine pH 1.5 (Cytiva) was used to regenerate the biosensors. We used Protein A biosensors (Sartorius) to attach the ACE2-Fc molecule to the biosensor’s surface. Then the analyte SARS-CoV-2 (COVID-19) S1 protein, His Tag (Aero Biosystems) was bound to the immobilized ACE2-Fc, which was the association phase. After 150 sec of association the next step was the dissociation for additional 150 sec. After evaluation the KD, kdis, ka values of ACE2-Fc were determined (by methods well-known in the art of enzyme kinetics) - S1 protein interaction, hence the binding strength between these molecules.
Steps of one cycle are shown in Table 2. Each sample means a new cycle.
Table 2 - steps of one cycle of a BLI assay
*After reach the appropriate wavelength threshold (0.5 nm) it continues the next step. Results
The results of the BLI assay carried out on native ACE2-Fc fusion protein and on 3x mutant variant (mutant variant having mutations R275L, T373F, H507L and N824G in comparison to the ACE2 domain and lgG1 -Fc region of SEQ ID NO: 1 , respectively) are shown in Table 3: Table 3
Representative sensorgram of the native ACE2-Fc fusion protein is shown in Figure 11 , representative sensorgram of the 3x mutant variant is shown in Figure 12. Furthermore, Figure 13 shows the respective equilibrium binding (KD) values on a diagram. The results clearly show the advantageous characteristics of the interaction between 3x mutant variant and S1 protein in comparison to the interaction between the native ACE2-Fc and S1 protein.
Claims
39
CLAIMS A mutated recombinant fusion protein comprising a human ACE2 domain and a human IgG-Fc domain, wherein in comparison to the ACE2 domain of SEQ ID NO: 1 , the ACE2 domain of the mutated recombinant fusion protein comprises mutation
(i) at positions R275, T373, H507; or
(ii) at positions R275, H347, T373, H507, 1515; or
(iii) at positions R275, H347, H507, 1515; or
(iv) at position 1515; or
(v) at positions T373, 1515; or
(vi) at position H507; or
(vii) at positions H507, 1515; or
(viii) at position T373. The mutated recombinant fusion protein according to claim 1 , wherein a mutation
(i) at position R275 is an exchange of R for L;
(ii) at position H347 is an exchange of H for G, V, A, L or I;
(iii) at position T373 is an exchange of T for F, Y or W;
(iv) at position H507 is an exchange of H for G, V, A, L or I; and/or
(v) at position 1515 is an exchange of I for T or S. The mutated recombinant fusion protein according to claim 2, wherein a mutation
(i) at position R275 is an exchange of R for L;
(ii) at position H347 is an exchange of H for A;
(iii) at position T373 is an exchange of T for F;
(iv) at position H507 is an exchange of H for L; and/or
(v) at position 1515 is an exchange of I for T. The mutated recombinant fusion protein according to any one of claims 1-3, wherein the human IgG-Fc domain of the mutated recombinant fusion protein is a human lgG1-Fc domain.
40 The mutated recombinant fusion protein according to claim 4, wherein in comparison to the lgG1 -Fc region of SEQ ID NO: 1 , the lgG1-Fc domain of the mutated recombinant fusion protein comprises mutation at position N824. The mutated recombinant fusion protein according to claim 5, wherein the mutation at position N824 is an exchange of N for G. The mutated recombinant fusion protein according to claim 6, wherein the mutated recombinant fusion protein comprises a sequence selected from the group consisting of SEQ ID NOs: 13, 14, 15, 16, 21 , 22, 23 and 24. The mutated recombinant fusion protein according to claim 6, wherein the mutated recombinant fusion protein has a sequence selected from the group consisting of SEQ ID NOs: 13, 14, 15, 16, 21 , 22, 23 and 24. The mutated recombinant fusion protein according to claim 6, wherein the mutated recombinant fusion protein has a sequence as shown by SEQ ID NO: 15. The mutated recombinant fusion protein according to any one of claims 1 -6, wherein the mutated recombinant fusion protein further comprises a signal peptide. The mutated recombinant fusion protein according to claim 10, wherein the mutated recombinant fusion protein comprises a sequence selected from the group consisting of SEQ ID NOs: 5, 7, 9, 11 , 17, 18, 19 and 20. The mutated recombinant fusion protein according to claim 10, wherein the mutated recombinant fusion protein has a sequence selected from the group consisting of SEQ ID NOs: 5, 7, 9, 11 , 17, 18, 19 and 20. The mutated recombinant fusion protein according to claim 10, wherein the mutated recombinant fusion protein has a sequence as shown by SEQ ID NO: 9.
41 The mutated recombinant fusion protein according to any one of claims 1 -13 for use in a method of treating an infection disease caused by a coronavirus capable of binding ACE2. The mutated recombinant fusion protein for use according to claim 14, wherein the coronavirus capable of binding ACE2 is SARS-CoV-2. The mutated recombinant fusion protein for use according to claim 14 or 15, wherein the infection disease is COVID-19. A polynucleotide encoding a mutated recombinant fusion protein, wherein the polynucleotide comprises a sequence as shown in any one of SEQ ID NOs: 6, 8, 10, 12. A vector comprising the polynucleotide according to claim 17. A host cell comprising the vector according to claim 18.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
HUP2100038 | 2021-02-03 | ||
HU2100038A HUP2100038A1 (en) | 2021-02-03 | 2021-02-03 | Mutated recombinant ace2-fc fusion proteins for the treatment of covid-19 infections |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2022167947A1 true WO2022167947A1 (en) | 2022-08-11 |
Family
ID=89993287
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/IB2022/050901 WO2022167947A1 (en) | 2021-02-03 | 2022-02-02 | Mutated recombinant ace2-fc fusion proteins for the treatment of covid-19 infections |
Country Status (2)
Country | Link |
---|---|
HU (1) | HUP2100038A1 (en) |
WO (1) | WO2022167947A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP4138998A4 (en) * | 2020-04-24 | 2024-05-22 | The Administrators of The Tulane Educational Fund | Compositions and methods for preventing or reducing the effects of infections by coronaviruses that bind the ace2 receptor |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2014144722A2 (en) * | 2013-03-15 | 2014-09-18 | Amgen Inc. | BISPECIFIC-Fc MOLECULES |
WO2021183717A1 (en) | 2020-03-11 | 2021-09-16 | Nantcell, Inc. | Proteinaceous therapeutics |
WO2021203098A2 (en) | 2020-04-03 | 2021-10-07 | The University Of North Carolina At Chapel Hill | Binding proteins useful against ace2-targeted viruses |
WO2021217120A2 (en) | 2020-04-24 | 2021-10-28 | Administrators Of The Tulane Educational Fund | Compositions and methods for preventing or reducing the effects of infections by coronaviruses that bind the extracellular domain of the ace2 receptor |
WO2022006601A1 (en) * | 2020-07-02 | 2022-01-06 | Northwestern University | Human recombinant ace2-fc mutants that decouple anti-sars-cov-2 activity from cardiovascular effects |
US20220056429A1 (en) * | 2020-08-18 | 2022-02-24 | New York University | Angiotensin-converting enzyme 2 (ace2) immunoadhesin microbody |
-
2021
- 2021-02-03 HU HU2100038A patent/HUP2100038A1/en unknown
-
2022
- 2022-02-02 WO PCT/IB2022/050901 patent/WO2022167947A1/en active Application Filing
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2014144722A2 (en) * | 2013-03-15 | 2014-09-18 | Amgen Inc. | BISPECIFIC-Fc MOLECULES |
WO2021183717A1 (en) | 2020-03-11 | 2021-09-16 | Nantcell, Inc. | Proteinaceous therapeutics |
WO2021203098A2 (en) | 2020-04-03 | 2021-10-07 | The University Of North Carolina At Chapel Hill | Binding proteins useful against ace2-targeted viruses |
WO2021217120A2 (en) | 2020-04-24 | 2021-10-28 | Administrators Of The Tulane Educational Fund | Compositions and methods for preventing or reducing the effects of infections by coronaviruses that bind the extracellular domain of the ace2 receptor |
WO2022006601A1 (en) * | 2020-07-02 | 2022-01-06 | Northwestern University | Human recombinant ace2-fc mutants that decouple anti-sars-cov-2 activity from cardiovascular effects |
US20220056429A1 (en) * | 2020-08-18 | 2022-02-24 | New York University | Angiotensin-converting enzyme 2 (ace2) immunoadhesin microbody |
Non-Patent Citations (19)
Title |
---|
DESMYTER, ACAD. SCI., vol. 110, 2013, pages E1371 - E1379 |
GLASGOW ET AL., PNAS, vol. 117, no. 45, 2020, pages 28046 - 55 |
HUANG ET AL., THE LANCET, vol. 395, 2020, pages 497 - 506 |
ISCIENCE, vol. 25, 21 January 2022 (2022-01-21), pages 103670 |
IWANAGA ET AL.: "Novel ACE2-lgG1 fusions with improved in vitro and in vivo activity against SARS-CoV-2", BIORXIV, 2020 |
KOCH ET AL.: "7", SCI. REP., 2017, pages 8390 |
KRUSE, F1000RESEARCH, vol. 9, 2020, pages 72 |
KRUSE, THERAPEUTIC STRATEGIES IN AN OUTBREAK SCENARIO TO TREAT THE NOVEL CORONAVIRUS ORIGINATING IN WUHAN, CHINA, vol. 9, 2020, pages 72 |
LEI ET AL., NAT. COMM., vol. 11, 2020, pages 2070 |
LI ET AL., NATURE, vol. 426, 2003, pages 450 - 454 |
LIU ET AL.: "Designed variants of ACE2-Fc that decouple anti-SARS-CoV-2 activities from unwanted cardiovascular effects", INT. J. BIOL. MACROMOL., vol. 165, 2020, pages 1626 - 1633, XP086393213, DOI: 10.1016/j.ijbiomac.2020.10.120 |
LIU PAN ET AL: "Designed variants of ACE2-Fc that decouple anti-SARS-CoV-2 activities from unwanted cardiovascular effects", INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES, ELSEVIER BV, NL, vol. 165, 17 October 2020 (2020-10-17), pages 1626 - 1633, XP086393213, ISSN: 0141-8130, [retrieved on 20201017], DOI: 10.1016/J.IJBIOMAC.2020.10.120 * |
MOORE ET AL., J VIROL., 2004, pages 10628 - 10635 |
TADA ET AL., CELL REP., vol. 33, 2020, pages 108528 |
TADA TAKUYA: "An ACE2 Microbody Containing a Single Immunoglobulin Fc Domain Is a Potent Inhibitor of SARS-CoV-2", CELL REP . 2020 DEC 22;33(12):108528, 22 December 2020 (2020-12-22), XP055918795, Retrieved from the Internet <URL:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7705358/pdf/main.pdf> [retrieved on 20220506] * |
URI ET AL., J. RENIN-ANGIOTENSIN-ALDOSTERONE SYST., vol. 17, no. 4, 2016, pages 1470320316668435 |
WANG ET AL., PROTEIN & CELL, vol. 9, 2018, pages 63 - 73 |
WONG ET AL., J. BIOL. CHEM., vol. 279, 2004, pages 3197 - 3201 |
ZOU ET AL., N. ENGL. J. MED., vol. 382, 2020, pages 1177 - 1179 |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP4138998A4 (en) * | 2020-04-24 | 2024-05-22 | The Administrators of The Tulane Educational Fund | Compositions and methods for preventing or reducing the effects of infections by coronaviruses that bind the ace2 receptor |
Also Published As
Publication number | Publication date |
---|---|
HUP2100038A1 (en) | 2022-08-28 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
Hsin et al. | Nucleocapsid protein-dependent assembly of the RNA packaging signal of Middle East respiratory syndrome coronavirus | |
CN111603557A (en) | Envelope-substituted virus vector vaccine and construction method thereof | |
JP3658690B2 (en) | Methods for obtaining natural domains of viral membrane proteins, especially their use as vaccines against HIV | |
CN113943373B (en) | Beta coronavirus polymer antigen, preparation method and application thereof | |
EA038250B1 (en) | RECOMBINANT CYTOMEGALOVIRUS gL PROTEIN WITH A MUTATION AT PROTEASE RECOGNITION SITE THAT REDUCES PROTEASE CLEAVAGE | |
CN115710311A (en) | Antibodies or antigen-binding fragments thereof to coronaviruses | |
JP2022538693A (en) | PROTEIN HYDROLYSIS TARGET VIRUS, LIVE VACCINE THEREOF, AND PRODUCTION METHOD AND USE THEREOF | |
CN109069616A (en) | RSV F protein before stabilized soluble fusion | |
Stauber et al. | Proteolytic cleavage of the murine coronavirus surface glycoprotein is not required for fusion activity | |
JP7472209B2 (en) | Conformational specific viral immunogens | |
CN109311946A (en) | RSV F protein before stabilized fusion | |
JP2008505050A (en) | SARS coronavirus S protein and use thereof | |
JP2023534421A (en) | Catalytic inactivation of angiotensin-converting enzyme 2 (ACE2) mutants and their use | |
WO2022167947A1 (en) | Mutated recombinant ace2-fc fusion proteins for the treatment of covid-19 infections | |
CN117320745A (en) | SARS-COV-2 subunit vaccine | |
US20070270361A1 (en) | Sars Nucleic Acids, Proteins, Vaccines, and Uses Thereof | |
US5543264A (en) | Co-factor activated recombinant adenovirus proteinases | |
WO2021235503A1 (en) | Conjugated protein monomer supporting coronavirus protein, aggregate of said monomers, and component vaccine comprising said aggregate as active component | |
Poumbourios et al. | Enhanced stability of the SARS CoV-2 spike glycoprotein following modification of an alanine cavity in the protein core | |
Behzadi et al. | A cross-reactive mouse monoclonal antibody against rhinovirus mediates phagocytosis in vitro | |
JP2005524392A (en) | Virus capsid assembly intermediate | |
Beltrán-Ortiz et al. | Expression and purification of the surface proteins from Andes virus | |
Zhu et al. | Important Changes in Biochemical Properties and Function of Mutated LLP12 Domain of HIV‐1 gp41 | |
TWI824468B (en) | SARS-CoV-2 VACCINE COMPOSITION AND USE THEREOF | |
US20230365640A1 (en) | Clec2 fusion protein and uses thereof |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 22708598 Country of ref document: EP Kind code of ref document: A1 |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 22708598 Country of ref document: EP Kind code of ref document: A1 |