Relative expression of proinflammatory molecules in COVID-19 patients who manifested disease severities

Abstract

Aggressive immune response, due to overexpressed proinflammatory molecules, has been characterized in coronavirus disease 2019 (COVID-19) patients. Some of those mediators have a dual and opposite role on immune systems at play behind differential disease severities. We investigated the expression of some cytokines and chemokines in COVID-19 patients in Bangladesh. We diagnosed the patients by detecting severe acute respiratory syndrome coronavirus 2 RNA in nasal swab samples by the real-time RT-PCR method. Thirty adult patients were preselected based on their disease severities and grouped into mild, moderate, and severe cases. Nine healthy volunteers participated in this study as a control. Relative expression of nine cytokines/chemokine in total leukocytes was semi-quantified in SYBRgreen-based real-time quantitative reverse-transcriptase polymerase chain reaction. We performed statistical tests on transformed log data using SPSS 24.0. At the onset of symptoms (Day 1), angiotensin-converting enzyme 2 (ACE2) (p < 0.05) and interleukin (IL)-6 (p > 0.05) were upregulated in all COVID-19 groups, although the expression levels did not significantly correlate with disease severities. However, expressions of IL-6, monocyte chemotactic protein-1, macrophage inflammatory protein-1α, tumor necrosis factor-α (TNF-α), RANTES (regulated upon activation, normal T cell expressed and secreted), and ACE2, on Day 14, were positively correlated with disease severities. Relative viral load at Day 1 showed no significant correlation with cytokine expression but had a significant positive correlation with RANTES and ACE2 expression on Day 14 (p < 0.05). Male patients had a higher level of IL-6 than female patients on Day 1 (p < 0.05). All COVID-19 patients showed upregulated cytokines and chemokines on Day 14 compared to Day 1 except TNF-α. Female patients had a higher expression of ACE2 and IL-12 on Day 14. Upregulated cytokines/chemokines at the convalescent stage, especially IL-6, may help in targeting anticytokine therapy in post-COVID-19 patients' management.