Clinical trial NCT00871637: Airway Macrophages and Sputum Milieu in Adult Subjects With Airflow Obstruction
Official title: Airway Macrophages and Sputum Milieu in Adult Subjects With Airflow Obstruction
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Pulmonary Disease, Chronic Obstructive
Bronchitis, Chronic
Occupational Diseases
Tobacco Use Disorder
Keywords: Pulmonary disease, chronic obstructive
Airway macrophages
Sputum milieu
Airway inflammation
Occupational diseases
Lead sponsor: University of Nebraska
Sponsor class: OTHER
Collaborators: name: VA Nebraska Western Iowa Health Care System
First posted: 2009-03-30
Enrollment: 30
Sex: ALL
Minimum age (years): 50
Maximum age (years): 75
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: CASE_CONTROL
Time perspective: PROSPECTIVE
Sampling method: PROBABILITY_SAMPLE
Study population: Three groups Group One : Healthy non-smoking controls Group Two : Smoking adults with chronic bronchitis/COPD Group Three: Non-smoking adults with chronic bronchitis/COPD

Brief summary: Airway macrophage impairment is a central feature in the immunopathogenesis of chronic obstructive pulmonary disease, regardless of smoking status.

Detailed description: In the United States, a variety of farming operations can generate significant amounts of dust. Chronic organic dust exposure to workers in this industry can result in several respiratory health conditions including chronic bronchitis, chronic obstructive pulmonary disease (COPD), and exacerbations of asthma. Organic dust is a complex mixture containing particulate matter and microbial-associated components from gram positive and gram negative bacteria. Airway macrophages are key innate immune cells that are rapidly activated by exposure to inhaled toxins and organic dust.

The literature indicates that subjects with tobacco-induced chronic bronchitis/COPD have alveolar macrophages that have impaired function. It has been hypothesized that the impaired lung macrophage function may contribute to the increased susceptibility to infections and chronic bacterial colonization that is a central feature in subjects with chronic bronchitis/COPD. It is unknown at this time if impaired macrophage function is secondary to tobacco-induced effects, or is a central pathologic feature of chronic bronchitis/COPD.

We will explore the expression of innate immune cell surface molecule expression involved in antigen presentation, phagocytic ability, and ex vivo cytokine responses in airway macrophages obtained by induced sputum. We will also collect blood to determine if ex vivo stimulation of blood mimics the inflammatory responses observed with airway macrophages. Comparisons to our past findings in vitro studies, which demonstrated that repetitive organic dust exposure impairs monocyte derived macrophage immune cell surface markers and function, could then be made. This information could lead to future investigations centered on therapeutic interventions to prevent or reverse the underlying lung disease experienced by farmers in this industry.

Eligibility criteria: Inclusion Criteria:

* Medically stable to participate in induced sputums
* Group One: Smoked less than 100 cigarettes in their lifetime Quit smoking greater than 10 years ago Pre-bronchodilator FEV1/FVC \> 70% Pre-bronchodilator FEV1 % predicted \> 80%
* Group Two: Greater than a 20-pack year tobacco history Smoked in the last two years Post-bronchodilator FEV1/FVC \< 70%
* Group Three:Have less than a 20-pack year tobacco history Quit smoking greater than 20 years ago Post-bronchodilator FEV1/FVC \< 70%

Exclusion Criteria:

* Personal history of lung cancer
* Pregnancy
* Personal history of autoimmune disease
* Currently taking oral/parental corticosteroids
* Personal history of upper or lower respiratory tract infection in the prior four weeks

Primary outcomes:
measure: Comparison of airway macrophages for immune cell surface marker expression and phagocytic ability in adults with airflow obstruction & healthy controls
timeFrame: One year
Secondary outcomes:
measure: Comparison of airway macrophages for cytokine responsiveness in adults with airflow obstruction & healthy controls
timeFrame: One year
measure: Comparison of airway macrophage cytokine responsiveness to whole blood cytokine responsiveness
timeFrame: One year
measure: Determining if immunomodulators in airway sputum milieu f predict airway macrophage phenotype and function
timeFrame: One year
Other outcomes:
Locations:
city: Omaha
country: United States
facility: University of Nebraska
state: Nebraska
Study officials:
affiliation: University of Nebraska
name: Jill A Poole, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Harting JR, Gleason A, Romberger DJ, Von Essen SG, Qiu F, Alexis N, Poole JA. Chronic obstructive pulmonary disease patients have greater systemic responsiveness to ex vivo stimulation with swine dust extract and its components versus healthy volunteers. J Toxicol Environ Health A. 2012;75(24):1456-70. doi: 10.1080/15287394.2012.722186.