proof of mechanism achieved with fewer subjects than anticipated

The primary objective of this study is to isolate macrophages by using bronchoalveolar lavage (BAL) for different in vitro experiments.

Therefore, following a baseline BAL, allergen, endotoxin, and saline will be instilled into three different lung segments during the first bronchoscopy. After 24 hours during a second bronchoscopy, BAL fluid will be collected in these challenged segments to harvest invaded cells for in vitro experimentation. In addition, segmental bronchial biopsies will be taken to assess the degree of local inflammation.

Inclusion Criteria:

• Physician diagnosis of atopy (allergic rhinitis or mild intermittent asthma)
• Age 18-55 years
• Nonsmoker (> 5 years)
• Forced expiratory volume in 1 second (FEV1) > 70% of the predicted value
• A positive skin prick test for grass mix or D. pteronyssinus at or within 12 months prior to the screening visit
• Informed consent
• Females with negative pregnancy test

Exclusion Criteria:

• Infections of the respiratory tract within the last month
• Past or present disease, which as judged by the investigator, may affect the outcome of this study. These diseases include, but are not limited to, cardiovascular disease, malignancy, hepatic disease, renal disease, hematological disease, neurological disease, endocrine disease or pulmonary disease (including but not confined to chronic bronchitis, emphysema, tuberculosis, bronchiectasis or cystic fibrosis).
• Pathological findings in blood tests (differential blood count, blood clotting, electrolytes, liver enzymes, retention parameters)
• Subject is undergoing allergen desensitization therapy
• Permanent medication
• Systemic or inhaled corticosteroid use within the last month
• Anti-inflammatory medication within the last month
• Pregnancy
• Neurological or psychiatric disease or history of drug or alcohol abuse which would interfere with the subject's proper completion of the protocol assignment
• There is a risk of non-compliance with study procedures
• Participation in a clinical trial 30 days prior to enrolment