Table 1. Summary of Published Studies Regarding IFN Production and ISG Response in COVID-19 Patients.
| Cohort | Specimen | ISG response | Production of IFN | Refs |
|---|---|---|---|---|
| 24 COVID-19, 24 healthy | PBMC | Moderate ISG response, strong chemokine expression | Low IFN-I and IFN-III level | 38 |
| 50 COVID-19 (15 mild-to-moderate, 17 severe, 18 critical), 18 healthy | PBMC | Impaired ISG response in severe and critical patients | No IFN-β low IFN-α production and activity in severe and critical patientes | 39 |
| 8 COVID-19, 5 severe influenza, 4 healthy | PBMC | Strong type I IFN response co-existing with TNF-IL-1β-driven inflammation in classical monocytes of severe patients | nd | 75 |
| 113 COVID-19 | PBMC | nd | Increased IFN-α production in severe patients | 74 |
| 26 COVID-19 (critical) | PBMC | Low ISG expression, ISG correlated with IFN-α2 measurement | Low or no IFN-α production, no IFN-β and IFN-λ production | 57 |
| 76 COVID-19, 69 healthy | PBMC | Increased ISG expression in T cells and monocytes which correlated with IFN-α concentration in plasma | Low IFN-α production, lack of type I IFN gene expression | 56 |
| 8 COVID-19, 20 healthy | BALF | Increased ISG expression and chemokine-dominant hypercytokinemia | nd | 72 |
| 7 COVID-19 (4 ARDS), 6 healthy | PBMC | Positive correlation between ISG of CD14+ monocytes and age, and negative correlation with time from fever onset | nd | 60 |
| 10 COVID-19, 5 healthy | BALF, naso-oropharyngeal swab | nd | Increased IFN-α, IFN-β, IFN-λ mRNA in BALF | 67 |
| 19 COVID-19, 5 healthy | Nasopharyngeal/pharyngeal swab | Overexpression of cytokine/chemokine genes in non-resident macrophages of the airway epithelium in critical patients | nd | 71 |
| 9 COVID-19 (3 moderate, 6 severe/critical), 4 healthy | BALF | Type I IFN response mainly expressed by neutrophils and FCN+ classical monocytes | nd | 76 |
| 5 COVID-19 (4 moderate, 1 severe), 2 IAV, 3 healthy | PBMC | Increased ISG expression, and severe patients show stronger response to IFN and virus infection | nd | 65 |
| 10 COVID-19, 5 healthy | PBMC | Increased ISG expression in CD14++ inflammatory monocytes | nd | 66 |
| 16 COVID-19, 6 normal | Post-mortem lung samples | Two distinct pattern: ISGhigh, high cytokine production, high viral loads, limited pulmonary damage/ISGlow, low viral loads, high infiltrating activated CD8+ T cells and macrophages | nd | 68 |
| 79 COVID-19 (35 ARDS), 26 influenza (7 ARDS), 15 healthy | PBMC | Lower expression of IFN-α response genes compared to influenza | nd | 55 |
IFN, interferon; COVID-19, coronavirus disease 2019; ISG, IFN-stimulated genes; TNF, tumor necrosis factor; ARDS; acute respiratory distress syndrome; PBMC, peripheral blood mononuclear cell; BALF, bronchoalveolar lavage fluid.