The Synergistic Role of Il-6 And IL-17 In the Protection Against Seasonal Influenza in Iraqi Population

Abstract

Seasonal influenza remains an important public health problem around the world. There are inadequate reports from Iraq about the immunological profile and viral subtypes associated with it. Cytokines, more specifically interleukin-6 (IL-6) and Interleukin-17 (IL-17), are known to play a major role in antiviral immune responses. The study aims to measure serum levels of IL-6 and IL-17 in patients diagnosed with SI against healthy control individuals, to compare them relative to vaccination status and viral subtypes as well as their correlation with each other. This study was done at the Central Laboratory of General Hospital in Hilla City from October 2024 up to February 2025. There were sixty-six patients SI and 34 controls aged between 22-56 years who participated in the study. Serological testing helped identify viral subtypes (H1N1, H3N2) while cytokine levels were established through ELISA. Vaccination status as well as demographic data were captured. IL-6 and IL-17 levels were significantly higher in patients than in the controls (p<0.001). Vaccinated patients had lower IL-6 levels (p=0.04). H3N2 was the most common subtype (91%). There is a moderate positive correlation between IL-6 and IL-17 levels, r=0.398, p=0.004. This Iraqi cohort of SI patients demonstrated raised levels of IL-6 and IL-17, particularly in infection with H3N2. This emphasizes the immunological influence of seasonal influenza and protective modulation of cytokines by vaccination. 

Keywords:

Seasonal influenza, cytokine response, IL-6 and IL-17, H3N2

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