Characterization of novel monoclonal antibodies against MERS-coronavirus spike protein.
Virus Res
; 278: 197863, 2020 03.
Article
em En
| MEDLINE
| ID: mdl-31945421
ABSTRACT
Middle East Respiratory Syndrome coronavirus (MERS-CoV) causes severe pulmonary infection, with â¼35 % mortality. Spike glycoprotein (S) of MERS-CoV is a key target for vaccines and therapeutics because S mediates viral entry and membrane-fusion to host cells. Here, four different S subunit proteins, receptor-binding domain (RBD; 358-606 aa), S1 (1-751 aa), S2 (752-1296 aa), and SΔTM (1-1296 aa), were generated using the baculoviral system and immunized in mice to develop neutralizing antibodies. We developed 77 hybridomas and selected five neutralizing mAbs by immunization with SΔTM against MERS-CoV EMC/2012 strain S-pseudotyped lentivirus. However, all five monoclonal antibodies (mAb) did not neutralize the pseudotyped V534A mutation. Additionally, one mAb RBD-14F8 did not show neutralizing activity against pseudoviruses with amino acid substitution of L506â¯F or D509â¯G (England1 strain, EMC/2012 L506â¯F, and EMC/2012 D509â¯G), and RBD-43E4 mAb could not neutralize the pseudotyped I529â¯T mutation, while three other neutralizing mAbs showed broad neutralizing activity. This implies that the mutation in residue 506-509, 529, and 534 of S is critical to generate neutralization escape variants of MERS-CoV. Interestingly, all five neutralizing mAbs have binding affinity to RBD, although most mAbs generated by RBD did not have neutralizing activity. Additionally, chimeric antibodies of RBD-14F8 and RBD-43E4 with human Fc and light chain showed neutralizing effect against wild type MERS-CoV KOR/KNIH/002, similar to the original mouse mAbs. Thus, our mAbs can be utilized for the identification of specific mutations of MERS-CoV.
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Texto completo:
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Glicoproteína da Espícula de Coronavírus
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Coronavírus da Síndrome Respiratória do Oriente Médio
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Anticorpos Monoclonais
Limite:
Animals
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Humans
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article