The Clinical Study Of Hyposensitization Of Allergen Nebulization To Prevent And Cure Bronchial Asthma

Obieetive:To explore the role of hyposensitization of allergen nebulization in the prevention and treatment of bronchial asthma,to study the function ofγδT cells in the pathogenesis of asthma.MeThods:20 patients with Der.p and Der.f allergy and chronic medium persistent asthma participated in a randomized study,group A(control group, n=10,3 patients withdrew midway)and group B(desensitized group, n=10).Group A were nebulized with 5ml normal saline while group B with specific allergen twice a week for five months.Both groups were nebulized with the effect of short-acting bronchodilatorsβ2-adrenoceptor agonist when attacked. The patients' clinic synthesis indexes were evaluated after therapy and before, including asthma symptom scores,allergy skin peak test(SPT),short-acting bronchodilatorsβ2-adrenoceptor dosage,lung function and airway responsiveness and adverse reactions of observation.The percentage ofγδT cells in peripheral blood and induced sputum and the percentage of IL-4 positiveγδT cells and IFN-γ,positiveγδT cells were detected by flow cytometry after therapy and before.Results:Asthma symptoms and airway responsiveness improved significantly better than before therapy in group B(1.56±1.24 VS 4.89±1.05,2.01±0.70 VS 0.90±0.78,P＜0.05),and there was a significant difference when compared with group A(5.29±0.76,P＜0.05);the presses of ventolin uses were decreased markedly between two groups.After therapy than in group B before treatment was significantly reduced(0.71±1.60 VS 5.50±1.84,P＜0.05),with group A(5.71±1.11)compared difference was significant (P＜0.05);the lung function have no changes after treatment in group B(P＞0.05);comparing the two groups before and after treatment,the SPT also showed no significant changes(P＞0.05).The percentage ofγδT cells in peripheral blood and induced sputum was lower than before therapy in group B (7.87±1.42 VS 11.79±2.7,10.05±2.81 VS 16.11±6.35,P＜0.05);after therapy, IFN-γpositiveγδT cells significantly increased(0.36±0.10 VS 0.14±0.07, P＜0.05)in induced sputum of group B;while the IL-4 positiveγδT cells was significantly decreased(0.12±0.04 VS 0.31±0.12,P＜0.05);the ratio of IFN-γpositiveγδT cells and IL-4 positiveγδT cells was marked higher after therapy (3.10±0.64 V S 0.54±0.16,P＜0.05),compared marked difference with group A (0.51±0.15,P＜0.05);but in peripheral blood,IL-4 positiveγδT and IFN-γpositiveγδT cells have no notable change(P＞0.05).Conclusion:The hyposensitization of allergen nebulization can reduce airway responsiveness,and is expected within a certain period of time to prevent or reduce asthma attack.γδT cells,the important cells in the pathogenesis of bronchial asthma,may have Th1/Th2 immune mode.The predominant expression ofγδT cells in people with asthma is Th2 mode.The symptoms of asthma were controlled effectively through hyposensitization,γδT cells may participated in this mechanism.