Interleukin-17 and the COVID-19 cytokine storm: Cases reports

ABSTRACT

We report two cases of patients with COVID-19. Clinical and biological features of the two patients confirm severe form of COVID-19 associated with cytokine storm. High levels of IL-6 and IL-17 were found. Unfortunately the patients died because of the multi-organ failure secondary to the cytokine storm. Cytokine storm is a systemic inflammatory syndrome which leads to aberrant release of cytokines. IL-6 is the most frequently reported cytokine to be increased in COVID-19 patients. Naive T CD4+ cells in the presence of TGF ß and IL-6 will differentiate into T helper 17 cells responsible for secreting IL-17A and 17F, target macrophages, dendritic cells, endothelial cells, and fibroblasts to increase the production of cytokines. IL-6 and IL-17 have been shown to play a role in increasing risk of airway disease. They synergistically promote viral persistence by protecting virus-infected cells from apoptosis. Immune hyperactivation in cytokine storm amplified levels of cytokines that will have systemic effects and cause collateral damage to vital organ systems. Immunotherapy can play a crucial role in COVID-19 managing. Tocilizumab an anti-IL6 receptor antibody was used with clinical improvement. The possibility of inhibiting IL17 as therapy for COVID-19 should be also considered.