Abstract
Objectives: To assess humoral and cellular immune responses against SARS-CoV-2 variants in COVID-19 convalescent and confirmed patients, to explore the correlation between disease severity, humoral immunity, and cytokines/chemokines in confirmed patients, and to evaluate the ADE risk of SARS-CoV-2.
Methods: Anti-RBD IgG were quantified using an ELISA. Neutralization potency was measured using pseudovirus and real virus. Cellular immunity was measured using ELISpot. Cytokine/chemokine levels were detected using multiplex immunoassays. In vitro ADE assays were performed using Raji cells.
Results: One-month alpha convalescents exhibited spike-specific antibodies and T cells for alpha and delta variants. Notably, the RBD-specific IgG towards the delta variant decreased by 2.5-fold compared to the alpha variant. Besides, serum from individuals recently experienced COVID-19 showed suboptimal neutralizing activity against the delta and omicron variants. Humoral immune response, IL-6, IP-10 and MCP-1 levels were greater in patients with severe disease. Moreover, neither SARS-CoV-1 nor SARS-CoV-2 convalescent sera significantly enhanced SARS-CoV-2 pseudovirus infection.
Conclusions: Significant resistance of the delta and omicron variants to the humoral immune response generated by individuals who recently experienced COVID-19. Furthermore, there was a significant correlation among disease severity, humoral immune response, and specific cytokines/chemokine levels. No evident ADE was observed for SARS-CoV-2.
Keywords: SARS-CoV-2 variants; cellular immune response; disease severity; humoral immune response; inflammatory mediators.
【저자키워드】 Cellular immune response, disease severity, SARS-CoV-2 variants, humoral immune response, inflammatory mediators., 【초록키워드】 COVID-19, SARS-CoV-2, IgG, immune response, Cytokines, Immunity, Cellular immune response, T cells, IL-6, disease severity, variant, SARS-CoV-2 variant, IP-10, risk, chemokines, delta variant, virus, SARS-CoV-1, Omicron variants, ELISA, chemokine, immune, immunoassays, serum, Humoral immunity, Neutralizing activity, T cell, SARS-CoV-2 variants, cellular immunity, pseudovirus, immune responses, Patient, MCP-1, Alpha, Omicron variant, ELISPOT, humoral immune response, Alpha variant, multiplex, convalescent, correlation, ADE, disease, patients, convalescent sera, specific antibodies, Humoral and cellular immune responses, Delta variants, cellular, Inflammatory mediators, severe disease, humoral, Anti-RBD IgG, mediators, individual, neutralization potency, alpha and delta variants, fold, pseudovirus infection, SARS-CoV-2 pseudovirus infection, RBD-specific IgG, spike-specific antibodies, Spike-specific antibody, Raji cells, was measured, greater, performed, evaluate, significantly, exhibited, Significant, quantified, 【제목키워드】 COVID-19, SARS-CoV-2, response, Against, Confirmed,