Israel Medical Association Journal

Objectives: To explore IL-17A-producing CD3+CD4+T cells in peripheral blood of patients with persistent AR and assess the degree of atopy, eosinophil count (Eo count), and bronchial hyper-responsiveness (BHR) to methacholine.

Methods: The study involved 61 patients and 30 controls. The percentage of CD3+CD4+IL-17A+T cells in peripheral blood was measured by flow cytometry, bronchial challenges with Mch were performed, as was skin prick tests with standard inhalant allergens, and Eo count was measured. Atopic status was determined by the number of positive SPT results and wheal mean diameter.

Results: A statistically significant difference in Th17 cell percentage was found in the AR and control groups (2.59 ± 1.32% and 1.24 ± 0.22% respectively, P = 0.001). Forty-one patients (67.2%) were polysensitized to indoor and outdoor allergens, while 20 (32.8%) had positive skin prick tests to indoor allergens. CD4+T cells were significantly higher in the patient group compared to the control group (2.91 ± 1.5% versus 1.91 ± 0.62%, P = 0.005), as was Eo count (4.48 ± 2.13 vs. 2.32 ± 1.83) (P = 0.0001). Forty-one in the AR group (67%) and 7 (23%) in the control group were Mch-positive (P = 0.001). The percentage of IL-17A-producing CD4+T cells was significantly higher in males compared to females (3.15 ± 1.8% versus 2.31 ± 0.9%, P = 0.02)

Conclusions: Polysensitized AR patients exhibited higher IL-17A-producing CD4+T cell levels and eosinophil counts. Male patients displayed a higher frequency of IL-17A-producing T cells. 

Background: Leukotriene antagonist therapy in asthmatic patients alleviates symptoms and improves exercise tolerance, however the effect of these drugs on bronchial provocation tests and exhaled nitric oxide levels are less clearly established.

Objective: To determine the effect of montelukast treatment on airway hyperresponsiveness to exercise, methacholine and adenosine-5’-monophosphate and on exhaled nitric oxide levels in steroid-naive asthmatics.

Methods: Following a 2 week run-in period, 20 mild to moderate asthmatics were enrolled in an open label 6 week trial of oral montelukast-sodium therapy. Bronchial hyperreactivity (exercise, methacholine and adenosine-5’-monophosphate challenges) and exhaled nitric oxide levels were measured before and after the 6 week period.

Results: Montelukast treatment resulted in a significant improvement in exercise tolerance: median DFEV₁ 20.0% (range 0–50) prior to treatment vs. 15.0% (range 0–50) post-treatment (P = 0.029). A significant difference was also observed for exhaled NO[1] following therapy: median NO 16.0 ppb (range 7–41) vs. 13.0 (range 4.8–26) (P = 0.016). No change was seen in baseline lung function tests (FEV₁, MEF₅₀) or in the bronchial responsiveness (PC₂₀) for methacholine and adenosine-5’-monophosphate.

Conclusions: This study demonstrates that the leukotriene antagonist, montelukast-sodium, reduces bronchial hyperreactivity in response to exercise and reduces exhaled nitric oxide levels but has little effect on bronchial responsiveness to methacholine and adenosine challenges.