NCT05773001 · Robert Tighe, MD
Macrophage Regulation of Ozone-Induced Lung Inflammation
(MOLI)
What this study is about
The purpose of this research study to understand how prior respiratory infections affect the susceptibility to lung inflammation following environmental exposures.
View original scientific description
The purpose of this research study to understand how prior respiratory infections affect the susceptibility to lung inflammation following environmental exposures.
Interventions
DRUG
Ozone
Subjects will perform alternating 15 minutes rest with 15 minutes treadmill walk exercise periods for 135 minutes in while breathing Ozone (O3).
Primary outcome measures
Change in the abundance of monocyte-derived alveolar macrophages
Time frame: Baseline, Day 18-20
Change in the abundance of monocyte-derived alveolar macrophages and association to measures of O3-induced inflammation (BAL cell neutrophils, albumin and cytokine production)
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Individuals between 18-55 yrs. of age (No subject will be excluded from the study on the basis of gender or ethnicity)
- Individuals with knowledge of prior respiratory viral infection history allowing them to be segregated into one of three cohorts
- Cohort 1 - No history of respiratory viral infection (defined as no symptoms consistent with respiratory viral infection nor history of a positive respiratory viral test)
- Cohort 2 - Documented mild respiratory viral infection (a positive test, either PCR- or antigen-based) but with mild to no symptoms and no evidence of a lower respiratory tract infection (including no hospitalization, and no oxygen use)
- Cohort 3 - History of respiratory viral infection and symptoms/imaging consistent with a lower respiratory tract infection who have recovered, are \>6 months out from their infection, and have normal lung function (spirometry with FVC, FEV1 and FEV1/FVC)
- There will be no maximal period from respiratory viral infection for inclusion in the study, the minimal period will be \>6 months out from infection
Exclusion criteria
- Individuals with prior respiratory viral pneumonia who have ongoing respiratory symptoms, are still using supplemental oxygen, or have abnormal lung function
- Current smokers of tobacco products including e-cigarettes or those with previous smoking history within the prior 5 years
- Pregnant women and women who are presently lactating.
- Subjects that have received antibiotic administration or an upper respiratory infection within the previous 4 weeks
- College and graduate students or employees who are under direct supervision by any of the investigators in this protocol
- Alcohol or illicit substance abuse
- Chronic cardio/pulmonary respiratory disorders or other medical conditions as determined by the investigator
- Increased airway hyperresponsiveness at baseline as measured by a positive methacholine challenge response (methacholine PC20 FEV1 \< 4 mg/ml)
- Subjects will be requested to refrain from antihistamines, nonsteroidal anti-inflammatory agents, antioxidants (e.g. beta-carotene, selenium, and lutein) and supplemental vitamins (e.g. C and E), for 1 week prior to, and during testing.
Where
- Durham, North Carolina
Collaborators
National Institutes of Health (NIH), National Institute of Environmental Health Sciences (NIEHS)
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced May 15, 2026 · Source of record for eligibility and locations