Interleukin-22 and interleukin-33 show up-regulated levels in the serum of patients with mild/moderate Coronavirus disease 2019

BACKGROUND: This study analyzed serum concentrations of interleukin (IL)-22 and IL-33 (pro-inflammatory and anti-inflammatory cytokines) in 90 patients with mild/moderate coronavirus disease 2019 (COVID-19) and 90 healthy controls. Enzyme-linked immunosorbent assay kits were used to measure IL-22 and IL-33 concentrations.

RESULTS: Median (interquartile range) concentrations of IL-22 and IL-33 were significantly higher in patients than in controls (IL-22: 18.6 [18.0-19.3] vs. 13.9 [12.1-14.9] pg/mL, probability [p]  control median) of IL-22 (odds ratio = 17.80 [95% CI: 6.48-48.90]; p = 0.001) and IL-33 (odds ratio = 19.0 [95% CI: 7.4-48.6]; p = 0.001) were more likely to develop COVID-19. A positive correlation was found between IL-22 and IL-33 and both cytokines also showed positive correlations with granulocyte-to-lymphocyte ratio and erythrocyte sedimentation rate in all participants.

CONCLUSIONS: IL-22 and IL-33 showed up-regulated concentrations in the serum of patients with mild/moderate COVID-19. Both cytokines may have prognostic value for COVID-19 along with their association with disease risk.