Mechanisms of Ozone-Induced Alterations in Efferocytosis and Phagocytosis

  • End date
    Jan 31, 2024
  • participants needed
  • sponsor
    Robert Tighe, MD
Updated on 4 October 2022
Accepts healthy volunteers


The purpose of this research study to understand how environmental and genetic factors may be involved in lung function. Healthy 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 performed under conscious sedation 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.


In brief, at V1 subjects will be assessed for baseline spirometry and venous blood analysis prior to exposure. The venous blood will be used to obtain PMNs for apoptosis assays, and serum for CFH and sCD163 levels. Additionally, this will be used to measure cytokines and growth factors. At each visit, if the subject is female, there will be a urine pregnancy test performed. Following this initial assessment, subjects will be challenged with FA or O3 and then spirometry will be performed, and venous blood will be obtained immediately following the exposure (V2). The subjects will then return 20 hours ±4h later for follow up studies (V3). There will be spirometry, a venous blood draw and urine pregnancy testing (if female) followed by bronchoscopy. At bronchoscopy, vital signs will be determined, including O2 sat. Patient then undergo an 18-20 day washout period before they are brought back in for V4 for the alternate challenge. This will follow the same protocol as outline above in the initial exposure and use the same series of analysis as the first set of visits. Therefore, we will fully characterize the biological response to ozone and filtered air in these same subjects.

Condition Healthy
Treatment Ozone, Filtered Air
Clinical Study IdentifierNCT03646877
SponsorRobert Tighe, MD
Last Modified on4 October 2022


Yes No Not Sure

Inclusion Criteria

• Individuals between 18-35 yrs. of age (No subject will be excluded from the study on the
basis of gender or ethnicity)

Exclusion Criteria

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
Alcohol or illicit substance abuse
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
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 < 8 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
Clear my responses

How to participate?

Step 1 Connect with a study center
What happens next?
  • You can expect the study team to contact you via email or phone in the next few days.
  • Sign up as volunteer  to help accelerate the development of new treatments and to get notified about similar trials.

You are contacting

Investigator Avatar

Primary Contact


Additional screening procedures may be conducted by the study team before you can be confirmed eligible to participate.

Learn more

If you are confirmed eligible after full screening, you will be required to understand and sign the informed consent if you decide to enroll in the study. Once enrolled you may be asked to make scheduled visits over a period of time.

Learn more

Complete your scheduled study participation activities and then you are done. You may receive summary of study results if provided by the sponsor.

Learn more

Similar trials to consider


Browse trials for

Not finding what you're looking for?

Every year hundreds of thousands of volunteers step forward to participate in research. Sign up as a volunteer and receive email notifications when clinical trials are posted in the medical category of interest to you.

Sign up as volunteer

user name

Added by • 



Reply by • Private

Lorem ipsum dolor sit amet consectetur, adipisicing elit. Ipsa vel nobis alias. Quae eveniet velit voluptate quo doloribus maxime et dicta in sequi, corporis quod. Ea, dolor eius? Dolore, vel!

  The passcode will expire in None.

No annotations made yet

Add a private note
  • abc Select a piece of text from the left.
  • Add notes visible only to you.
  • Send it to people through a passcode protected link.
Add a private note