en ایمنی شناسی Immunology مقالات اصلی Original Article <p style="text-align: justify;"><strong><em>Background: </em></strong>Rhinitis, which occurs most commonly as allergic rhinitis and affects 20% of the world&rsquo;s population, is a major health care burden causing significant morbidity. Considering the high prevalence of allergic rhinitis and anti-inflammatory effects of thyme, a favorite condiment, we performed a randomized clinical trial to determine whether thyme can relieve allergic rhinitis symptoms and affect the expression of TH17- and T-regulatory cell- (Treg) related cytokines IL-17, TGF-&beta;, FOXP3, and IL-10.<br> <strong><em>Methods:</em></strong> Thirty patients with allergic rhinitis symptoms and positive skin prick test for common aero allergens were randomly assigned to experimental or control groups. The experimental group received thyme or <em>Zataria multiflora </em>(ZM<em>) </em>extracts and the control group received placebo for two months. Expression of IL-17, TGF-b, FOXP3, and IL-10 was evaluated in all subjects by real-time PCR before and after intervention.<br> <strong><em>Results:</em></strong> After treatment IL-17 expression was significantly less in the ZM group than in controls (p<0.05), while TGF-&beta;, FOXP3, and IL-10, expression were not significantly changed.<br> <strong><em>Conclusions:</em></strong> Given the significant effect of thyme in reducing symptoms of allergic rhinitis and decrease IL-17 gene expression and because allergic rhinitis is a multifactorial disease, the administration of thyme extract along with conventional treatments may benefit allergic rhinitis sufferers.</p> Allergic rhinitis, IL-17, Herbal product, Thyme, Zataria multiflora. 203 207 http://rbmb.net/browse.php?a_code=A-10-41-2&slc_lang=en&sid=1 Nazila Ariaee ariaeen931@mums.ac.ir 10031947532846007665 10031947532846007665 No Allergy research Center, Mashhad University of Medical sciences, Mashhad Iran. Jalal Ghorbani ghornani.jalal@yahoo.com 10031947532846007666 10031947532846007666 No Allergy research Center, Mashhad University of Medical sciences, Mashhad Iran. Maryam Panahi panahim941@mums.ac.ir 10031947532846007667 10031947532846007667 No Allergy research Center, Mashhad University of Medical sciences, Mashhad Iran. Mojgan Mohamadi Mohammdimzh@mums.ac.ir 10031947532846007668 10031947532846007668 No Allergy research Center, Mashhad University of Medical sciences, Mashhad Iran. Javad Asili asilij@mums.ac.ir 10031947532846007669 10031947532846007669 No Department of Pharmacognosy, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran. Alireza Ranjbar ranjbara@mums.ac.ir 10031947532846007670 10031947532846007670 No Interventional Allergology and Immunology, University of Colgan, Bonn, Germany. Reza Farid Hoseini faridr@mums.ac.ir 10031947532846007671 10031947532846007671 No Allergy research Center, Mashhad University of Medical sciences, Mashhad Iran. Farahzad Jabbari Jabbarif@mums.ac.ir 10031947532846007672 10031947532846007672 Yes Allergy research Center, Mashhad University of Medical sciences, Mashhad Iran.