Effect of Exposure to Allergens and Air Pollution on Lung Function and Immunity
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 18
- 试验地点
- 2
- 主要终点
- Allergen-specific IgE
研究概览
简要总结
The investigators are investigating the effects of combined exposures to diesel exhaust and allergens on lung function and on the immune system. After exposing individuals to either filtered air or carefully controlled levels of diesel exhaust in our exposure chamber, The investigators will use a procedure called bronchoscopy (whereby a thin, flexible tube is passed down the throat and into the lungs) to place a small amount of allergen directly in the lung. 48h later, the bronchoscopy will be repeated so that samples can be collected from the lungs. After 1mo, the entire procedure will be repeated with the alternate exposure.
详细描述
- Purpose/Objective:
To study the effects of diesel exhaust particles on lung function and on allergic responses. 2. Hypotheses:
Hypothesis 1: DE exposure augments systemic oxidative stress from allergen challenge in allergen-sensitized individuals.
Hypothesis 2: DE exposure augments allergen-specific immune response in allergen-challenged airways in sensitized individuals. These responses will be greater in asthmatic individuals than in non-asthmatics. 3. Justification:
The use of diesel engines is increasing because they are more fuel-efficient than gasoline engines. However, diesel engines produce different emissions than gasoline engines. Diesel exhaust is emitted from the tailpipe of both "on-road" diesel engine vehicles (diesel cars, buses and trucks) and "non-road" diesel engines (locomotives, marine vessels and some construction equipment). Diesel exhaust consists of both gaseous and particulate air pollutants. Since people with asthma and allergic diseases appear to be sensitive to air pollution, we would like to know how diesel exhaust (DE) can affects your respiratory and immune systems. We are expecting that any responses that may occur will only be detectable through careful examination of cells and tissues (e.g., bronchoalveolar lavage (fluid from your lungs), blood, urine). Understanding these potentially subtle changes will help us prevent health problems associated with air pollution in the future. 4. Research Method:
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Basic Science
- 盲法
- Triple (Participant, Investigator, Outcomes Assessor)
入排标准
- 年龄范围
- 19 Years 至 49 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Age between 19 and 49 years.
- •Non-smoking.
- •Positive skin prick test for at least one of: birch, grass, or dust
排除标准
- •Using inhaled corticosteroids
- •Pregnant or planning to be pregnant in the next 12 months / Breastfeeding
- •Usage of bronchodilators more than three times per week.
- •Co-morbidities (as assessed by the primary investigator)
- •Taking part in other studies
- •Unwilling to withhold bronchodilator, aspirin, anti-coagulant, antihistamine or decongestant medications or caffeine prior to testing procedures.
- •FEV1(Forced expiratory volume in one second) < 70% predicted.
- •Allergy to lidocaine, fentanyl, midazolam or salbutamol.
- •Unstable asthma (i.e exacerbation in 2 weeks preceding testing)
结局指标
主要结局
Allergen-specific IgE
时间窗: 48 hours
BAL IgE specific to the allergen used for allergen challenge will be assessed at 48 hrs, from the BAL, using immunocap assay
次要结局
- Human immune response(48 hours)
- Airway reactivity(48 hours)
- Oxidative stress(48 hours)
研究者
Christopher Carlsten
Principal Investigator
University of British Columbia