Relative expression of pro-inflammatory molecules in COVID-19 patients manifested disease severities. (preprint)

ABSTRACT

Aggressive immune response, due to over-expressed pro-inflammatory molecules, had been characterized in COVID-19 patients. Some of those mediators have a dual and opposite role on immune-systems to 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 SARS-CoV-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 control. Relative expression of nine cytokines/chemokine in total leukocytes was semi-quantified in SYBRgreen-based qRT-PCR. We performed statistical tests on transformed log data using SPSS 24.0. At the onset of symptoms (day-1), ACE2 (P < 0.05) and IL-6 (P > 0.05) were up-regulated in all COVID-19 groups, although expression levels did not significantly correlate with disease severities. However, expression of IL-6, MCP-1, MIP-1, TNF-, RANTES, 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 up-regulated cytokines and chemokines on the day-14 compared to day-1 except TNF-. Female patients had higher expression of ACE2 and IL-12 on day-14. Up-regulated cytokines/chemokines at the convalescent stage, especially IL-6, may target anti-cytokine therapy in post-COVID-19 patients management.