| In the course of the coronavirus disease 2019 (COVID‐19), raising and reducing
the function of Th17 and Treg cells, respectively, elicit hyperinflammation and
disease progression. The current study aimed to evaluate the responses of Th17
and Treg cells in COVID‐19 patients compared with the control group. Forty
COVID‐19 intensive care unit (ICU) patients were compared with 40 healthy
controls. The frequency of cells, gene expression of related factors, as well as the
secretion levels of cytokines, were measured by flow cytometry, real‐time polymerase
chain reaction, and enzyme‐linked immunosorbent assay techniques, respectively.
The findings revealed a significant increase in the number of Th17 cells,
the expression levels of related factors (RAR‐related orphan receptor gamma
[RORγt], IL‐17, and IL‐23), and the secretion levels of IL‐17 and IL‐23 cytokines in
COVID‐19 patients compared with controls. In contrast, patients had a remarkable
reduction in the frequency of Treg cells, the expression levels of correlated factors
(Forkhead box protein P3 [FoxP3], transforming growth factor‐β [TGF‐β], and
IL‐10), and cytokine secretion levels (TGF‐β and IL‐10). The ratio of Th17/Treg
cells, RORγt/FoxP3, and IL‐17/IL‐10 had a considerable enhancement in patients
compared with the controls and also in dead patients compared with the improved
cases. The findings showed that enhanced responses of Th17 cells and decreased
responses of Treg cells in 2019‐n‐CoV patients compared with controls
had a strong relationship with hyperinflammation, lung damage, and disease
pathogenesis. Also, the high ratio of Th17/Treg cells and their associated factors in
COVID‐19‐dead patients compared with improved cases indicates the critical role
of inflammation in the mortality of patients. |