Objectives: As COVID-19 rages on worldwide, there is an urgent need to characterize immune correlates of protection from SARS-CoV-2 infection and to identify immune determinants of COVID-19 severity. Methods: We present longitudinal profiles of neutralizing antibody titers in hospitalized COVID-19 patients clinically diagnosed with mild symptoms, pneumonia, and severe pneumonia up to 12 months after illness onset, using live-virus neutralization. Multiplex, correlation, and network analyses were used to characterize serum-derived inflammatory cytokine profiles in all severity groups. Results: Peak NAb titers correlated with disease severity, and NAb titers declined over the course of 12 months regardless of severity. Multiplex analyses revealed that IP-10, IL-6, IL-7, and VEGF-α were significantly elevated in severe pneumonia cases compared to mild symptoms and pneumonia cases. Correlation and network analyses further suggested that cytokine network formation was distinct in different COVID-19 severity groups. Conclusions: Our findings inform on the long-term kinetics of naturally acquired serological immunity against SARS-CoV-2 and highlight the importance of identifying key cytokine networks for potential therapeutic immunomodulation.

Fuente: International Journal of Infectious Diseases
Available online 15 September 2021
In Press, Journal Pre-proof