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Published on: September 20, 2024
High Levels of Circulating IL-8 and Soluble IL-2R Are Associated With Prolonged Illness in Patients With Severe
Aiping Ma1, Liang Zhang2, Xiaokai Ye3
1Department of Respiratory and Critical Medicine, The First Affiliated Hospital, School of Medicine, Xiamen University, Xiamen, China.
Objectives:
The coordinated immune response of the host is the key of the successful combat of the body against SARS-CoV-2 infection and is decisive for the development and progression of COVID-19. In this study, we aimed to investigate whether the immunological phenotype of patients are associated with duration of illness in patients with severe COVID-19.
Method:
In this single-center study, 69 patients with severe or critical COVID-19 were recruited retrospectively. Immunological parameters including counts of white blood cells, neutrophils, lymphocytes, the neutrophil-to-lymphocyte ratio, and levels of circulating cytokines and cytokine receptors were screened for their association with disease severity, survival and duration of illness of COVID-19.
Results:
Our data confirmed previous results that neutrophil-to-lymphocyte ratio and circulating levels of IL-6 represent prominent biomarker for the prediction of disease severity and survival of COVID-19. However, this study shows for the first time that duration of illness in patients with severe COVID-19 is positively associated with serum levels of IL-8 (P=0.004) and soluble IL-2Rα (P=0.025).
Conclusion:
The significant association of duration of illness with circulating levels of IL-8 and soluble IL-2Rα in patients with severe COVID-19 implicates that neutrophils and T cells are involved in the evolution of COVID-19.

