Evaluation of Chemokines and Cytokines as Biomarkers for Disease Severity in COVID-19-Infected Patients

Background: Alterations in cytokine and chemokine levels during SARS-CoV-2 infection may serve as indicators of disease severity. Objectives: This study aimed to evaluate the levels of plasma cytokines and chemokines in patients with COVID-19. Methods: The study included 120 COVID-19 patients, divided into severe, mild, and recovered categories (n = 40 for each group). Plasma levels of cytokines such as interleukin 8 (IL-8) and tumor necrosis factor α (TNF-α) were measured using ELISA, while chemokines like monocyte chemoattractant protein 1 (MCP-1) and programmed death protein 1 (PD-1) were quantified through qRT-PCR. Results: A higher incidence of positive biomarkers IL-8, TNF-α, MCP-1, and PD-1 was observed in the severe group compared to the mild and recovered groups. Notably, the expression levels of PD-1 and MCP-1 were significantly elevated in severely infected individuals relative to those in healthy subjects. A strong positive correlation was also noted between PD-1 and MCP-1 levels in cases of severe infection. Conclusions: The findings suggest that MCP-1, PD-1, TNF-α, and IL-8 could act as biomarkers for assessing the severity of COVID-19 infections. These results aim to deepen our understanding of the immunopathological mechanisms at play in this disease.