Interleukin 9 serum level and single nucleotide polymorphism in patients with asthma.

Background: Asthma is a chronic inflammatory disease of airways which accounts for a huge economic, morbidity and mortality burden. There are different cytokines that contribute to asthma pathophysiology. Learning about these cytokines leads to attaining novel anti-inflammatory treatments for asthma control.

Objectives: The objective of this study is to investigate the association between interleukin-9 serum level and gene polymorphism with asthma susceptibility.

Methods: This was a case-control study of 70 asthmatic patients and 77 healthy control adults aged 18-60. Asthma diagnosis and severity were based on physician diagnosis, pulmonary function test (PFT) and 2016 guild line of Global Initiative for Asthma (GINA). Interleukin 9(IL -9) serum level was measured using sandwich enzyme linked immunosorbent assay.  IL9 promoter single nucleotide polymorphism (SNP) (rs2069882) was also assessed using Real-Time PCR System.

Results: There was no significant association between IL-9 SNP polymorphism and asthma. IL-9 serum level was significantly associated with asthma susceptibility (p value= 0.016) and absolute eosinophil count (AEC) (P value=0.033) however its corelation with atopic asthma type, asthma sivierity and Immunoglubin E serum level were not statistically significant.

Conclusion: Although there was no association between IL-9 SNP and asthma, but IL-9 serum level was significantly correlated with asthma susceptibility and AEC.