Viral dynamics and immune correlates of coronavirus disease 2019 (COVID-19) severity

• Main Authors: Young, Barnaby Edward, Ong, Sean W. X., Ng, Lisa F. P., Anderson, Danielle E., Chia, Wan Ni, Chia, Po Ying, Ang, Li Wei, Mak, Tze-Minn, Kalimuddin, Shirin, Chai, Louis Yi Ann, Pada, Surinder, Tan, Seow Yen, Sun, Louisa, Parthasarathy, Purnima, Fong, Siew-Wai, Chan, Yi-Hao, Tan, Chee Wah, Lee, Bernett, Rötzschke, Olaf, Ding, Ying, Tambyah, Paul, Low, Jenny G. H., Cui, Lin, Barkham, Timothy, Lin, Raymond Tzer Pin, Leo, Yee Sin, Renia, Laurent, Wang, Lin-Fa, Lye, David Chien
• Other Authors: Lee Kong Chian School of Medicine (LKCMedicine)
• Format: Article
• Language: English
• Published: 2022
• Subjects: Science::Medicine; COVID-19; Cytokines
• Online Access: https://hdl.handle.net/10356/162756
• Institution: Nanyang Technological University

Background. Key knowledge gaps remain in the understanding of viral dynamics and immune response of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection. Methods. We evaluated these characteristics and established their association with clinical severity in a prospective observational cohort study of 100 patients with PCR-confirmed SARS-CoV-2 infection (mean age, 46 years; 56% male; 38% with comorbidities). Respiratory samples (n = 74) were collected for viral culture, serum samples for measurement of IgM/IgG levels (n = 30), and plasma samples for levels of inflammatory cytokines and chemokines (n = 81). Disease severity was correlated with results from viral culture, serologic testing, and immune markers. Results. Fifty-seven (57%) patients developed viral pneumonia, of whom 20 (20%) required supplemental oxygen, including 12 (12%) with invasive mechanical ventilation. Viral culture from respiratory samples was positive for 19 of 74 patients (26%). No virus was isolated when the PCR cycle threshold (Ct) value was >30 or >14 days after symptom onset. Seroconversion occurred at a median (IQR) of 12.5 (9–18) days for IgM and 15.0 (12–20) days for IgG; 54/62 patients (87.1%) sampled at day 14 or later seroconverted. Severe infections were associated with earlier seroconversion and higher peak IgM and IgG levels. Levels of IP-10, HGF, IL-6, MCP-1, MIP-1α, IL-12p70, IL-18, VEGF-A, PDGF-BB, and IL-1RA significantly correlated with disease severity. Conclusions. We found virus viability was associated with lower PCR Ct value in early illness. A stronger antibody response was associated with disease severity. The overactive proinflammatory immune signatures offer targets for host-directed immunotherapy, which should be evaluated in randomized controlled trials.