Background Evidence points to the emergence of a novel human coronavirus, Middle East respiratory syndrome coronavirus (MERS-CoV), which causes a severe acute respiratory syndrome (SARS)-like disease. In response, the development of effective vaccines and therapeutics remains a clinical priority. To accomplish this, it is necessary to evaluate neutralizing antibodies and screen for MERS-CoV entry inhibitors. Methods In this study, we produced a pseudovirus bearing the full-length spike (S) protein of MERS-CoV in the Env-defective, luciferase-expressing HIV-1 backbone. We then established a pseudovirus-based inhibition assay to detect neutralizing antibodies and anti-MERS-CoV entry inhibitors. Results Our results demonstrated that the generated MERS-CoV pseudovirus allows for single-cycle infection of a variety of cells expressing dipeptidyl peptidase-4 (DPP4), the confirmed receptor for MERS-CoV. Consistent with the results from a live MERS-CoV-based inhibition assay, the antisera of mice vaccinated with a recombinant protein containing receptor-binding domain (RBD, residues 377–662) of MERS-CoV S fused with Fc of human IgG exhibited neutralizing antibody response against infection of MERS-CoV pseudovirus. Furthermore, one small molecule HIV entry inhibitor targeting gp41 (ADS-J1) and the 3-hydroxyphthalic anhydride-modified human serum albumin (HP-HSA) could significantly inhibit MERS-CoV pseudovirus infection. Conclusion Taken together, the established MERS-CoV inhibition assay is a safe and convenient pseudovirus-based alternative to BSL-3 live-virus restrictions and can be used to rapidly screen MERS-CoV entry inhibitors, as well as evaluate vaccine-induced neutralizing antibodies against the highly pathogenic MERS-CoV.
【저자키워드】 Neutralizing antibodies, MERS-CoV, Spike protein, pseudovirus, antiviral therapeutics, Novel human coronavirus, 【초록키워드】 neutralizing antibody, IgG, HIV, coronavirus, Infection, MERS-CoV, inhibitors, viral entry, DPP4, Dipeptidyl peptidase-4, Protein, pseudovirus, mice, RBD, receptor, entry inhibitors, inhibitor, disease, Neutralizing antibody response, Antisera, Safe, Middle East, acute respiratory syndrome, Human serum albumin, residue, domain, respiratory syndrome coronavirus, backbone, full-length, highly pathogenic, Cell, BSL-3, Result, produced, detect, evaluate, significantly, inhibit, exhibited, can be used, variety, demonstrated, cause, effective vaccine, expressing, luciferase-expressing HIV-1, MERS-CoV entry, MERS-CoV pseudovirus, fused,