多聚肌苷酸在支气管哮喘防治中的价值

摘要

目的 研究多聚肌苷酸[polyinosinic:polycytidylic acid,Poly (I:C)]在支气管哮喘防治中的意义.方法 将健康雌性Balb/c 6周龄小鼠80只,随机分为对照组、致敏组、激发前干预组、激发时干预组,每组20只.除对照组外,其余3组小鼠用OVA致敏建立哮喘模型,其中激发前干预组在OVA激发前给予Poly (I:C)干预；激发时干预组在OVA激发同时给予Poly (I:C)干预.通过乙酰胆碱量测定评定气道反应性,ELISA测定血浆IgE水平；测定肺泡灌洗液(BALF)中的细胞总数Eos计数； IL-4和IFN-y浓度；肺组织切片测定IL-4和IFN-γ mRNA浓度.结果 致敏组、激发前干预组、激发时干预组小鼠对乙酰胆碱的反应性明显高于对照组,差异均有统计学意义(P＜0.05)；3组哮喘小鼠之间的差异无统计学意义(P＞0.05).3组哮喘小鼠的血浆IgE水平、BALF中的细胞总数和Eos计数、IL-4和IFN-γ浓度、肺组织中IL-4和IFN-γmRNA水平与对照组比较,差异均有统计学意义(P＜0.05),且3组哮喘小鼠之间的差异也有统计学意义(P＜0.05).结论 在OVA激发前、激发时给予Poly (I:C),均不能改变哮喘小鼠对乙酰胆碱的气道反应性；在OVA激发前给予Poly (I:C)干预可减轻炎症反应,但在OVA激发哮喘时给予Poly (I:C)干预则可加重炎症反应.%Objective To evaluate the value of polyinosinic: polycytidylic acid (poly I: C) in the prevention and treatment of the bronchial asthma. Methods Eighty healthy female BALB/c mice at 6 weeks of age were randomly divided into control group, ovalbumin (OVA) sensitized group, intervention group A and intervention group B, with 20 mice in each group. To establish a murine model of asthma, BALB/c mice were sensitized and challenged by OVA except for the mice in control group. Poly (I:C) was administered before OVA challenge in intervention group A, while Poly (I:C) was given at the same time as OVA challenge in intervention group B. Airway responsiveness of mice was determined by measuring the provocative concentration of acetylcholine after OVA challenge. The level of plasma IgE was tested by ELISA. The total number of cells and eosinophils were counted and the concentrations of IL-4 and IFN-γ were determined in bronchoalveolar lavage fluid (BALF). IL-4 and IFN-γ mRNA expression levels in lung tissues were measured. Results Airway responsiveness to acetylcholine of mice in OVA sensitized group and intervention groups A and B was significantly higher than that in control group (P＜0.05), but the difference was not significant among three asthma groups. The level of plasma IgE, the total number of cells and eosinophils and the concentrations of IL-4 and IFN-γ in BALF, and IL-4 and IFN-γ mRNA expression levels in mouse lung tissues in three asthma groups were significantly different from those in mice of control group (P＜0.05), and furthermore there were significant differences among three asthma groups. Conclusions Whether poly (I:C) was asministered before or at the same time as OVA challenge, the airway responsiveness to acetylcholine of asthma mice will not be changed. The inflammatory response can be alleviated by poly (I:C) given before OVA challenge, but aggravated by poly (I:C) given at the same time as OVA challenge.