TABLE 2.
Observed fluctuation in DCs and DC subsets in adult COVID-19 patients.
| DC type | Observation | Analyzed patients | Compared group(s) | References |
| DCs | Reduction (%) | Hospitalized | HD | Zhou R. et al., 2020 |
| Reduction (%) | Convalescent | HD | Zhou R. et al., 2020 | |
| CD11c+ cDCs | Reduction (%) | Hospitalized | Convalescent | Zhou R. et al., 2020 |
| Reduction (%)/ | Severe/Critical+ | HD | Matic et al., 2020 | |
| Reduction (%)/ | Severe/Critical+ | Mild/Moderate& | Matic et al., 2020 | |
| No change (%) | Mild$ | Convalescent | Neeland et al., 2021 | |
| Increase (%) | Mild/Moderate& | HD | Matic et al., 2020 | |
| CD123-CD11c+ myeloid DCs | Reduction (%) | Pneumonia | HD | Zingaropoli et al., 2021 |
| Reduction (%) | ARDS | non-ARDS | Zingaropoli et al., 2021 | |
| CD11c+ slanDCs | Reduction (%) | Pneumonia | HD | Zingaropoli et al., 2021 |
| AXL+SIGLEC6+ pre-DCs | Reduction (#) | Cases | HD | Kvedaraite et al., 2021 |
| AXL+CD1c+ pre-DC2 | Reduction (#) | Cases | HD | Kvedaraite et al., 2021 |
| CLEC9A+ cDC1 | Reduction (#) | Cases | HD | Kvedaraite et al., 2021 |
| CLEC9A- cDC2* | Reduction (#) | Cases | HD | Kvedaraite et al., 2021 |
| CD163-CD14- DC3 | Reduction (#) | Cases | HD | Kvedaraite et al., 2021 |
| CD163-CD14+ DC3 | Reduction (#) | Cases | HD | Kvedaraite et al., 2021 |
| CD163+CD14+ DC3 | Reduction (#) | Cases | HD | Kvedaraite et al., 2021 |
| CD5+DC2 | Reduction (%) | Severe§ | Moderate@ | Kvedaraite et al., 2021 |
| CD163-CD14- DC3 | Reduction (%) | Severe§ | Moderate@ | Kvedaraite et al., 2021 |
| AXL+CD1c+ pre-DC2 | Increase (%) | Severe§ | HD | Kvedaraite et al., 2021 |
| CD123+CD11c- pDCs | Reduction (#) | Cases | HD | Kvedaraite et al., 2021 |
| Reduction (%) | ARDS | non-ARDS | Zingaropoli et al., 2021 | |
| Reduction (%) | Pneumonia | HD | Zingaropoli et al., 2021 | |
| CD123+Lyn- pDCs | Reduction (%)/ | Severe/Critical+ | HD | Matic et al., 2020 |
| Reduction (%)/ | Severe/Critical+ | Mild/Moderate& | Matic et al., 2020 | |
| Reduction (%) | Mild/Moderate& | HD | Matic et al., 2020 |
DC, dendritic cell; cDCs, conventional dendritic cells; pDCs, plasmacytoid dendritic cells; (%), as frequency values; (#), as absolute number; HD, healthy donors; ARDS, acute respiratory distress syndrome; Cases, COVID-19 patients (irrespective of severity).
/No statistically significant data provided.
+Fever or suspected respiratory infection with compromised respiratory function and worsening of respiratory symptoms with the necessity for mechanical ventilation.
&Mild clinical symptoms of upper respiratory tract viral infection and signs of pneumonia without need for supplemental oxygen. *Including CD5+ DC2 and CD5– DC3.
@Oxygen saturation -SO2- between 90 and 94% or 0.5 to 3 L/min oxygen requirement at screening.
§Treated at the intensive care unit -ICU- or at a high-dependency unit.
$Including coryza, headaches, nausea, fever, cough, sore throat, malaise, headaches, and muscle aches.