Characterization of neutralizing monoclonal antibodies recognizing a 15-residues epitope on the spike protein HR2 region of severe acute respiratory syndrome coronavirus (SARS-CoV).
The spike (S) glycoprotein is thought to play a complex and central role in the biology and pathogenesis of SARS coronavirus infection. In this study, a recombinant protein (rS268, corresponding to residues 268-1255 of SARS-CoV S protein) was expressed in Escherichia coli and was purified to near homogeneity. After immunization with rS268, S protein-specific BALB/c antisera and mAbs were induced and confirmed using ELISA, Western blot and IFA. Several BALB/c mAbs were found to be effectively to neutralize the infection of Vero E6 cells by SARS-CoV in a dose-dependent manner. Systematic epitope mapping showed that all these neutralizing mAbs recognized a 15-residues peptide (CB-119) corresponding to residues 1143-1157 (SPDVDLGDISGINAS) that was located to the second heptad repeat (HR2) region of the SARS-CoV spike protein. The peptide CB-119 could specifically inhibit the interaction of neutralizing mAbs and spike protein in a dose-dependent manner. Further, neutralizing mAbs, but not control mAbs, could specifically interact with CB-119 in a dose-dependent manner. Results implicated that the second heptad repeat region of spike protein could be a good target for vaccine development against SARS-CoV.
Lai
Szu-Chia
SC
Institute of Preventive Medicine, National Defense Medical Center, 90048-700, San-Hsia, Taipei, Taiwan.
Chong
Pele Choi-Sing
PC
Yeh
Chia-Tsui
CT
Liu
Levent Shih-Jen
LS
Jan
Jia-Tsrong
JT
Chi
Hsiang-Yun
HY
Liu
Hwan-Wun
HW
Chen
Ann
A
Wang
Yeau-Ching
YC
D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000737:chemistry* / Q000276:immunology; D001483:Base Sequence; D015153:Blotting, Western; D017931:DNA Primers; D024202:Electrophoretic Mobility Shift Assay; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000737:chemistry* / Q000276:immunology; D019084:Fluorescent Antibody Technique, Indirect; D008562:Membrane Glycoproteins / Q000737:chemistry* / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D009500:Neutralization Tests; D045473:Severe acute respiratory syndrome-related coronavirus / Q000276:immunology*; D064370:Spike Glycoprotein, Coronavirus; D014759:Viral Envelope Proteins / Q000737:chemistry* / Q000276:immunology
D000911:Antibodies, Monoclonal; D017931:DNA Primers; D000939:Epitopes; D008562:Membrane Glycoproteins; D064370:Spike Glycoprotein, Coronavirus; D014759:Viral Envelope Proteins; C578557:spike glycoprotein, SARS-CoV; C578553:spike protein, mouse hepatitis virus