Elevated anti-SARS-CoV-2 antibodies and IL-6, IL-8, MIP-1β, early predictors of severe COVID-19.

BackgroundViral and host immune kinetics during acute COVID-19 and after remission of acute symptoms need better characterization. MethodsSARS-CoV-2 RNA, anti-SARS-CoV-2 IgA, IgM, and IgG antibodies, and pro-inflammatory cytokines were measured in sequential samples among hospitalized COVID-19 patients during acute infection and 6 months following diagnosis. Results24 laboratory-confirmed COVID-19 patients with mild/moderate and severe COVID-19 were included. Most were males 83%, median age of 61 years. 21% were admitted to the ICU and 8 of them (33.3%) met criteria for severe COVID-19 disease. A delay in SARS-CoV-2 levels decline during the first 6 days of follow-up and viral load persistence until month 3 were related with severe COVID-19, but not viral load levels at the diagnosis. Higher levels of anti-SARS-CoV-2 IgA, IgM, IgG and the cytokines IL-6, IL-8 and MIP-1{beta} at the diagnosis time were related with severe COVID-19 outcome. Higher levels of MIP-1{beta}, IL-1{beta}, MIP-1 and IFN-{gamma} were observed at month 1/3 during mild/moderate disease compared to severe COVID-19. IgG persisted at low levels after 6 months of diagnosis. ConclusionsHigher concentrations of IgA, IgM, and IgG, and IL-6, IL-8 and MIP-1{beta} are identified as early predictors of COVID-19 severity, but not SARS-CoV-2 RNA levels at diagnosis.