Immune Response in Hypersensitivity Pneumonitis
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|ClinicalTrials.gov Identifier: NCT03873649|
Recruitment Status : Recruiting
First Posted : March 13, 2019
Last Update Posted : August 28, 2019
|Condition or disease||Intervention/treatment|
|Hypersensitivity Pneumonitis||Other: Bronchoscopy with lavage|
Hypersensitivity pneumonitis (HP) is a granulomatous lung disorder triggered by exposure to one of a multitude of organic antigens. Incidence rates of HP vary by geography, season and population studied but it is estimated to be the third most common interstitial lung disease with an estimated prevalence rate in the USA of 420-3000/100,0002. HP accounts for at least 7.5% of ILD related lung transplant. Exposure to an antigen in a susceptible host induces an inflammatory response with the subsequent formation of poorly formed granulomas that impact gas exchange which clinically manifests as shortness of breath, hypoxia and radiographic changes. HP can present acutely, subacutely or chronically depending on the duration of symptoms and radiographic changes. Radiographic manifestations of HP include ground-glass changes, centrilobular nodules, air trapping known as mosaic pattern, fibrosis, emphysema, or more frequently a combination of these. The cornerstone of management is identification and avoidance of the inciting agent which is effective if accomplished early in the disease process.
Although detection and avoidance of possible triggers can attenuate or reverse the disease, a significant number of patients continue to have active and/or progressive disease requiring chronic immunosuppressive therapy. Standard of care for IS therapy is corticosteroids and azathioprine but this is based on clinical experience and not based on randomized clinical trials(ref). The efficacy of this regimen is not known and patients develop persistent or progressive disease in spite of aggressive therapy leading to end stage lung disease necessitating lung transplantation or ending with death. To date, there are no randomized trials for immunosuppressive therapies and no reports of the use of biological agents in HP. The lack of studies is partially due to the lack of a thorough understanding of the immune response in HP especially in patient based studies that focus at the site of disease activity, the lungs.
The immunological response and pathways leading to this response have not been fully investigated especially in humans. The Th17 pathway has been implicated in disease pathogenesis and T-regulatory cell dysfunction has been described although studies in humans are limited. Recent work in sarcoidosis, a granulomatous lung disease, has shown that Th17.1 cells play a potential important role in granuloma immunopathogenesis. Through an R01 mechanism, the investigators are currently investigating the role of T-cell skewing and associated gene expression in sarcoidosis that is associated with progressive disease vs stable disease and the investigators are investigating its impact on disease course.
This gap in knowledge in HP has limited the choice and study of immunomodulatory agents in HP and especially biological agents in the treatment of persistent and progressive disease. To narrow this knowledge gap, the investigators propose conducting a study to investigate the lung CD4+ T-cell immunophenotype and CD4+ T-cell gene expression in HP to enhance the investigators' understanding of the immune response in HP and the pathways involved in the immune response which would enable the investigators to further pursue guided therapeutic trials in subacute and chronic HP.
|Study Type :||Observational|
|Estimated Enrollment :||10 participants|
|Official Title:||CD4 T-cell Immunephenotype in Hypersensitivity Pneumonitis|
|Actual Study Start Date :||November 29, 2018|
|Estimated Primary Completion Date :||June 30, 2021|
|Estimated Study Completion Date :||June 30, 2021|
Patients with subacute or chronic hypersensitivity pneumonitis
Procedures that each subject will undergo include:
Other: Bronchoscopy with lavage
Bronchoscopy will be performed according to standard clinical procedures. Bronchoscopy will be performed under conscious sedation with continuous cardiopulmonary monitoring and the subject's upper airway will be anesthetized with topical lidocaine. The bronchoscope will be passed through the naris or mouth to the upper airway and then into the lower airway. 360cc of sterile saline will be instilled into 2 sub-segments by instilling and aspirating 3 aliquots of 60cc sequentially into each sub-segment.
Venipuncture to obtain peripheral blood mononuclear cells (PBMCs) for the proposed assays.
Cells collected will be analyzed for various T-cell subsets and gene expression to help determine the type of immune response.
Other Name: blood draw
- T-cell subtypes [ Time Frame: outcomes will be assessed after recruitment is complete in 2 years. ]T-cell subtypes will be determined by flow cytometry.
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03873649
|Contact: Nabeel Hamzeh, MDemail@example.com|
|Principal Investigator:||Nabeel Hamzeh, MD||University of Iowa|