ABSTRACT Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) possesses a discriminative polybasic cleavage motif in its spike protein that is recognized by the host furin protease. Proteolytic cleavage activates the spike protein, thereby affecting both the cellular entry pathway and cell tropism of SARS-CoV-2. Here, we investigated the impact of the furin cleavage site on viral growth and pathogenesis using a hamster animal model infected with SARS-CoV-2 variants bearing mutations at the furin cleavage site (S gene mutants). In the airway tissues of hamsters, the S gene mutants exhibited low growth properties. In contrast to parental pathogenic SARS-CoV-2, hamsters infected with the S gene mutants showed no body weight loss and only a mild inflammatory response, thereby indicating the attenuated variant nature of S gene mutants. This transient infection was sufficient for inducing protective neutralizing antibodies that cross-react with different SARS-CoV-2 lineages. Consequently, hamsters inoculated with S gene mutants showed resistance to subsequent infection with both the parental strain and the currently emerging SARS-CoV-2 variants belonging to lineages B.1.1.7 and P.1. Taken together, our findings revealed that the loss of the furin cleavage site causes attenuation in the airway tissues of hamsters and highlighted the potential benefits of S gene mutants as potential immunogens.
【저자키워드】 SARS-CoV-2, Neutralizing antibodies, spike, furin cleavage site, attenuation, 【초록키워드】 Mutation, Pathogenesis, Neutralizing antibodies, furin, hamsters, body weight, variant, SARS-CoV-2 variant, Infection, animal model, Spike protein, airway, Severe acute respiratory syndrome, Viral, SARS-CoV-2 variants, B.1.1.7, P.1, furin cleavage site, Lineage, pathway, Mild, cleavage, mutants, cell tropism, attenuation, cellular entry, mutant, hamster, respiratory, lineages, severe acute respiratory syndrome-coronavirus-2, furin protease, Inflammatory response, S gene, weight loss, tissue, growth, pathogenic, potential benefits, viral growth, motif, proteolytic cleavage, immunogens, Body weight loss, protective neutralizing antibodies, Host, inoculated, subsequent, investigated, exhibited, the spike protein, potential benefit, cause, activate, parental, affecting, cross-react, infected with SARS-CoV-2, polybasic, protective neutralizing antibody, 【제목키워드】 S1/S2, Bearing, Site,