Strengthening the Case for Ongoing Reduction of Exposure to Traffic-Related Air Pollution
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 13
- 试验地点
- 2
- 主要终点
- Immune response to allergen +/- DE (BAL)
研究概览
简要总结
The study probes the effects of combined exposures to diesel exhaust and allergens on lung function and on the immune system, specifically focusing on the ability of a particle depletion technique to attenuate effects we and others have seen previously. Individuals are exposed to either filtered air (FA), carefully controlled levels of diesel exhaust (DE) or particle-depleted diesel exhaust (PDDE) in our exposure chamber, after which the investigators will administer an inhaled allergen challenge. 48h later, a procedure called bronchoscopy is used to collect samples from the lungs. After 1 month, the entire procedure is to be repeated with one of the alternate exposures. This will be repeated 4 times (4 exposures; 2 filtered air, 1 diesel exhaust, 1 particle-depleted diesel exhaust)
详细描述
- Purpose/Objective:
The aim of this study is to investigate the ability of depletion of diesel exhaust particles to attenuate adverse effects of diesel exhaust on lung function and on allergic responses. 2. Hypotheses:
Hypothesis 1: Allergen-specific immune response (specific IgG4, etc; relevant responses in DNA methylation and proteomics) in allergen-challenged airways in sensitized individuals is increased by diesel exhaust "synergy".
Hypothesis 2: Synergistic responses will be greater in asthmatics than in non-asthmatics.
Hypotheses 3: Synergy is attributable to the particulate fraction of DE (i.e. is normalized by particle depletion). 3. Justification:
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)
研究组 & 干预措施
Filtered air
Exposure for 2 hours to filtered air followed by subject specific inhaled allergen challenge
干预措施: Allergen (Other)
Diesel exhaust
Exposure for 2 hours to diesel exhaust followed by subject specific inhaled allergen challenge
干预措施: Allergen (Other)
Filtered air control
Exposure for 2 hours to filtered air followed by inhaled saline challenge
干预措施: Saline (Other)
Particle depleted diesel exhaust
Exposure for 2 hours to particle depletion diesel exhaust followed by inhaled allergen challenge
干预措施: Allergen (Other)
Particle depleted diesel exhaust
Exposure for 2 hours to particle depletion diesel exhaust followed by inhaled allergen challenge
干预措施: Particle depleted diesel exhaust (Other)
结局指标
主要结局
Immune response to allergen +/- DE (BAL)
时间窗: 48 hours
BAL cellular differential and activation,
Immune response to allergen +/- DE (Th1/Th2/IgE/IgG4)
时间窗: 48 hours
Th1/Th2 profile and IgE and IgG4 specific to the allergen used for allergen challenge will be assessed.
次要结局
- Proteomic signature(48 hours)
- Epithelial cell DNA methylation(48 hours)
研究者
Christopher Carlsten
Principal Investigator
University of British Columbia