Association of serum level and gene expression of IL-25 in a sample of Iraqi asthmatic patients

Asthma is an increasingly common disease characterized by allergic airway inflammation, hyperresponsiveness, mucus overproduction, and peribronchial fibrosis. The epithelial cytokines IL25 have been implicated in asthma pathogenesis because they promote Th2-type cytokine synthesis. The current study aimed to assess IL-25 expression and measure the serum level of this cytokine in asthmatic Iraqi patients. The study was conducted on sixty (60) asthmatic patients (32 female and28 male) and thirty as apparently healthy subjects (control) (16 female and 14 male) with ages ranging from 15-60 years recruited Alzahra’a Center for Asthma and Allergy in Baghdad during the period between November /2021 to March /2022. Written informed consent was obtained from all patients and a healthy control group. Moreover, the study design was approved by the Institute of Genetic Engineering and Biotechnology for Postgraduate Studies/ University of Baghdad. All patients were diagnosed according to clinical examination by a chest physician and selected according to the global initiative of asthma criteria. The healthy control group are non-smoking subjects with no history of obstructive lung disease or atopy. The RNA was extracted from the whole blood of asthma patients and healthy control without Trizol subjects using the protocol in Easy Pure t® blood RNA Kit (ER-401). The acceptable purity of asthmatic patients and control healthy group RNA ranges between 1.84 and 1.99. IL-25 gene expression showed the Ct of asthma patient group (25.179) and control group (27.393), and the2-ΔΔCt of asthma patient group (288.81) and control group (58.48) and the fold of gene expression was statistically significantly (P≤0.01) the calculation of the gene expression it was significant in the patient group than control group4.938 times with ratio (4.938:1) . ELISA estimated IL-25concentration, the results were statistically significant (P≤0.001), the level of IL-25 in asthma patient group (29.30± 5.107317pg/ml) while the level of IL-23 in Control group (15.16±0.085248pg/ml). Keywords: IL-25, gene expression, Elisa, Asthma