An interventional study of Bronchoscopy/BAL and Airway Brushing in Asthma, Allergic, sponsored by Andrew D. Luster, M.D.,Ph.D.. Completed at 1 site in United States. Open to participants aged 18 Years to 55 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-09-30.
Sponsored by Andrew D. Luster, M.D.,Ph.D. · Not applicable, Interventional, and Basic science
Rahimi RA, Smith NP, Selle A, Best R, Martin S, Tuttle E, Said W, Samanta N, Ling MF, Medoff BD, Villani AC, Luster AD. Distinct phenotypes and repertoires of…PubMed 41519381 ↗
Determining how memory T helper type 2 (Th2) initiate recall responses to aeroallergens has the potential to change the therapeutic approach to allergic asthma, the most common asthma subtype. \~5-10% of effector Th2 cells recruited into the lung give rise to long-lived tissue resident memory cells that are poised to respond upon allergen re-exposure.Consequently, targeting memory Th2 cell activation is an attractive therapeutic strategy. However, it is not well understood how allergen inhalation initiates a memory Th2 cell response in the lung. The focus of this new study on the role of lung-resident memory Th2 cells in orchestrating the recall response to allergen in the lung, including the recruitment and activation of circulating Th2 cells, is a natural, timely and exciting extension of the investigators' ongoing Allergen Challenge Protocol.
The objective of this study is to define the mechanisms whereby Th2-Trm persisting in the lung orchestrates a recall response to inhaled allergens. The investigators' central hypothesis is that Th2-Trm ignite allergic airway inflammation via a rapid and enhanced response to cognate antigen in the airway and the ability to recruit circulating Th2 cells (Th2-Tcr) to the sites of antigen presentation in the lung. Mechanistically, the investigators hypothesize that Th2-Trm co-localize with DCs expressing the Th2 cell-attracting chemokine CCL17 and after allergen re-challenge rapidly produce type 2 cytokines that initiate allergic inflammation and markedly enhance DC expression of CCL17. This increased CCL17 expression recruits Th2-Tcr cells from the blood to sites of antigen presentation where Th2-Tcr receive a "second touch" from cognate antigen loaded and activated DCs and become fully competent to amplify allergic inflammation. The investigators propose to use innovative experimental systems to define the function of Th2-Trm, including single cell RNA-seq analysis of human airway mucosal CD4+ T cells obtained via bronchial brushing. Specifically, the investigators propose to define the transcriptional phenotype of human lung Th2-Trm and Th2-Tcr. Defining the mechanisms regulating Th2-Trm function in the asthmatic airway has the potential to yield new therapeutic approaches for allergic asthma. Memory CD4+ T helper type 2 (Th2) cells are critical in promoting allergic asthma, the most common asthma endotype. The investigators propose to define the function of newly described lung-resident memory Th2 cells in driving recurrent allergic airway inflammation. The successful completion of the proposed study has the potential to focus new asthma therapies on specifically targeting the biology of lung-resident memory Th2 cells.
4,841 studies on the registry are indexed under Asthma; 600 are open to participants now.
This study's enrollment of 37 is below the median of 78 across 3,341 interventional studies indexed under Asthma.
Browse Asthma studies →Andrew D. Luster, M.D.,Ph.D. is the lead sponsor of 3 studies on the registry; none are open to participants now.
Counted across the registry records on this site, refreshed daily.
Mild to moderate allergic asthma (AA) subjects
Inclusion Criteria:
All subjects will have a clinical history of allergic symptoms to an indoor allergen present in their home environment, either cat, dog or dust mite allergen, and confirmed skin reactivity (a positive allergen prick test) to the same allergen. The investigators will recruit both:
Exclusion Criteria:
Healthy Control (HC) Subjects HC subjects will be individuals who are in good overall health, age and sex matched to the asthmatic group, age 18 - 55 and nonallergic, i.e. entirely negative on a panel of prick skin tests that includes trees, grasses, weeds, cat, dog, dust mites, cockroach and molds, with no history of allergic rhinitis or asthma, no history of allergic symptoms caused by cats, dogs, or dust mite allergen exposure, life-long nonsmokers of cigarettes (defined as a lifetime total of \< 5 packyears and none in 5 years), normal spirometry (i.e. FEV1 and FVC of at least 90% of predicted) and with a negative methacholine challenge test (PC20 of > 25 mg/ml).
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
From a breathing test (spirometry): how much air you can blow out in the first second. Often given as a percentage of what is expected for your age, height and sex.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
FEV1
From a breathing test (spirometry): how much air you can blow out in the first second. Often given as a percentage of what is expected for your age, height and sex.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Allergic Asthmatic or Healthy Control Adults will undergo Bronchoscopy/BAL and airway brushing
Procedure: Bronchoscopy/BAL · Procedure: Airway Brushing
Participants may receive 3 inhalations (90 ug ea) of albuterol to minimize bronchoconstriction. Medication includes midazolam by intravenous injection, and fentanyl by intravenous injection as judged necessary. 2% lidocaine is delivered via atomizer spray to the oral pharynx for local anesthesia. 1% lidocaine is delivered through the bronchoscope to the vocal cords and lung segments for local anesthesia. The bronchoscope is then passed through the vocal cords into the trachea. Throughout the procedure, all participants will have continuous blood pressure, heart rate, and oxygen saturation monitoring. Participants will be instructed to relate any discomfort or problems through a series of standardized hand signals. Once in the lung, aliquots of sterile saline are instilled into two subsegments of the right middle lobe (preferred and if not possible then the right upper lobe) and withdrawn into a trap by gentle suction.
After completion of the BALs, endobronchial brushing of the airways will be performed using the airway brushings with a Conmed Harrell™ 4 mm unsheathed cytology brush. Upon completing the brushing the investigators remove the bronchoscope with the brush in place to avoid shearing off isolated cells. The brush will be gently glided back and forth on the airway epithelium 10 times in 2 different locations within the same airway. The brush is then placed in media and flicked to remove the cells. A second brush will then be introduced into an adjacent airway of the same lobe and gently glided back and forth on the airway epithelium 10 times in 2 different locations as was done with the first brush. The second brush will also be placed in media and flicked to remove the cells. There is some airway bleeding caused by the procedure, and participants are made aware that they may cough up small amounts of blood for 24-48 hours following the procedure.
The phenotype of Th2-Trm recovered from the airway mucosa
The investigators will determine the phenotype of Th2-Trm recovered from the airway mucosa of humans with asthma via flow cytometry to define the phenotype of human Th2-Trm. The T cells will be recovered from airway bronchial brushing samples of patients with allergic asthma and allergy to an indoor allergen, and the investigators will obtain comparative samples from nonallergic healthy control subjects.
Time frame: This is a single time point study with all information obtained at the time of bronchoscopy defined as Day 0.
The transcriptional profile of Th2-Trm recovered from the airway mucosa
The investigators will determine the transcriptional profile of Th2-Trm recovered from the airway mucosa of humans with asthma via single-cell RNA-seq analysis to define the phenotype of human Th2-Trm. The T cells will be recovered from airway bronchial brushing samples of patients with allergic asthma and allergy to an indoor allergen, and the investigators will obtain comparative samples from nonallergic healthy control subjects.
Time frame: This is a single time point study with all information obtained at the time of bronchoscopy defined as Day 0.
Plan to share: No
Ran from May 2019 to primary completion in Nov 2024, 65 months.
Of 599 non-industry interventional studies with no phase under Asthma, half reached primary completion within 24 months of starting (the median), counting those still running; a quarter within 11 and three quarters within 50. This study's 65 months is above that.
Counting every sponsor, half of 649 studies reached it within 23 months; a quarter within 10 and three quarters within 48.
Completion moved once since we started tracking on Sep 25, 2026: Dec 2027 → Sep 2026, on Sep 30, 2026.
Earlier changes are on the record history on ClinicalTrials.gov ↗
How these figures are worked out, and which studies are left out of them.
Rahimi RA, Smith NP, Selle A, Best R, Martin S, Tuttle E, Said W, Samanta N, Ling MF, Medoff BD, Villani AC, Luster AD. Distinct phenotypes and repertoires of…PubMed 41519381 ↗
Rahimi RA, Smith NP, Selle A, Best R, Martin S, Tuttle E, Said W, Samanta N, Ling MF, Medoff BD, Villani AC, Luster AD. Distinct phenotypes and repertoires of…PubMed 41519381 ↗
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is completed, as verified in Sep 2026. You cannot join it, but the record below documents what was studied.
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Andrew D. Luster, M.D.,Ph.D.