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Macrophage Regulation of Ozone-Induced Lung Inflammation

Macrophage Regulation of Ozone-Induced Lung Inflammation

Status
Recruiting
Phases
Phase 1
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05773001
Acronym
MOLI
Enrollment
100
Registered
2023-03-17
Start date
2023-05-18
Completion date
2028-05-01
Last updated
2026-05-15

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Respiratory Viral Infection

Brief summary

The purpose of this research study to understand how prior respiratory infections affect the susceptibility to lung inflammation following environmental exposures.

Detailed description

Study participants will undergo a 1-day screening that includes a blood draw and breathing testing, return for a two-day series of testing to include blood draw, and brief breathing test before and after an inhaled challenge with either filtered air (FA) or ozone (O3). Participants return the next day for a brief breathing test, a blood draw and a procedure called bronchoscopy to evaluate the lung after the challenge. Participants then return 18 - 20 days later to repeat the two-day series of testing to be challenged with the exposure not received on the first series, (FA or O3). Each visit will take about 3 - 3.5 hours. Follow-up phone calls from the study team will occur at 24 hours after each 2-day test series. Total study duration is about one to one-and a half months.

Interventions

DRUGOzone

Subjects will perform alternating 15 minutes rest with 15 minutes treadmill walk exercise periods for 135 minutes in while breathing Ozone (O3).

Sponsors

Robert Tighe, MD
Lead SponsorOTHER
National Institutes of Health (NIH)
CollaboratorNIH
National Institute of Environmental Health Sciences (NIEHS)
CollaboratorNIH

Study design

Allocation
NON_RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
OTHER
Masking
SINGLE (Subject)

Eligibility

Sex/Gender
ALL
Age
18 Years to 55 Years
Healthy volunteers
Yes

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.

Design outcomes

Primary

MeasureTime frameDescription
Change in the abundance of monocyte-derived alveolar macrophagesBaseline, Day 18-20Change in the abundance of monocyte-derived alveolar macrophages and association to measures of O3-induced inflammation (BAL cell neutrophils, albumin and cytokine production)

Secondary

MeasureTime frameDescription
Change in the abundance of autonomous CSF-1 expression in alveolar macrophagesBaseline, Day 18-20Change in the abundance of autonomous CSF-1 expression in alveolar macrophages and association to measures of O3-induced inflammation
Association between prior evidence of respiratory viral pneumoniaBaseline, Day 18-20Association between prior evidence of respiratory viral pneumonia, when compared to non-infected individuals, and O3-induced inflammation
Association between prior evidence of respiratory viral infection without pneumoniaBaseline, Day 18-20Association between prior evidence of respiratory viral infection without pneumonia, when compared to non-infected individuals and O3-induced inflammation

Countries

United States

Contacts

CONTACTClaudia Salazar
claudia.salazar@duke.edu9196602026
PRINCIPAL_INVESTIGATORRobert Tighe, MD

Duke University

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: May 16, 2026