Airway Macrophages and Sputum Milieu in Adult Subjects With Airflow Obstruction

September 1, 2023 updated by: University of Nebraska
Airway macrophage impairment is a central feature in the immunopathogenesis of chronic obstructive pulmonary disease, regardless of smoking status.

Study Overview

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.

Study Type

Observational

Enrollment (Actual)

30

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • Nebraska
      • Omaha, Nebraska, United States, 68198
        • University of Nebraska

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

50 years to 75 years (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

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

Description

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

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
Group One
Healthy non-smoking controls
Group Two
Smoking adults with chronic bronchitis/chronic obstructive pulmonary disease
Group Three
Non-smoking adults with chronic bronchitis/chronic obstructive pulmonary disease

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Comparison of airway macrophages for immune cell surface marker expression and phagocytic ability in adults with airflow obstruction & healthy controls
Time Frame: One year
Determine if airway macrophages from adult participants with airflow obstruction demonstrate impaired innate immune cell surface marker expression and phagocytic ability compared to healthy controls.
One year

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Comparison of airway macrophages for cytokine responsiveness in adults with airflow obstruction & healthy controls
Time Frame: One year
Determine if airway macrophages from adult participants with airflow obstruction demonstrate impaired cytokine responsiveness compared to healthy controls.
One year
Comparison of airway macrophage cytokine responsiveness to whole blood cytokine responsiveness
Time Frame: One year
Determine if airway macrophage cytokine responsiveness is comparable to whole blood cytokine responsiveness.
One year
Determining if immunomodulators in airway sputum milieu f predict airway macrophage phenotype and function
Time Frame: One year
To determine if airway sputum milieu for potential immunomodulators predict airway macrophage phenotype and function.
One year

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Jill A Poole, MD, University of Nebraska

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

August 1, 2008

Primary Completion (Actual)

June 1, 2009

Study Completion (Actual)

June 1, 2009

Study Registration Dates

First Submitted

March 26, 2009

First Submitted That Met QC Criteria

March 26, 2009

First Posted (Estimated)

March 30, 2009

Study Record Updates

Last Update Posted (Actual)

September 7, 2023

Last Update Submitted That Met QC Criteria

September 1, 2023

Last Verified

September 1, 2023

More Information

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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