Study Results
The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.
Basic Information
Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.
COMPLETED
OBSERVATIONAL
1999-01-31
2006-12-31
Brief Summary
Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.
Related Clinical Trials
Explore similar clinical trials based on study characteristics and research focus.
Community Based Study of Adult Onset Asthma
NCT00005544
Isocyanate Antigens and T Cells That Cause Asthma
NCT00005549
Inflammatory Processes in the Airway of Asthmatics With Persistent Bronchial Hyperreactivity
NCT00217854
Air Pollution, Inflammation, and New Onset Asthma
NCT00241696
Biomarkers in Exhaled Breath From Asthmatic Patients
NCT00635271
Detailed Description
Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.
Endotoxin (or lipopolysaccharide \[LPS\]) is a potent inflammatory stimulant which is found in ambient air in occupational settings. Asthma in the workplace is an increasingly significant problem. Asthma is characterized by airway inflammation and increased reactivity to both allergic and non-allergic stimuli. LPS is known to induced airway inflammation in normal subjects and to enhance airway reactivity in asthmatics. Additionally, both alveolar macrophages and mononuclear cells from asthmatics secrete higher amounts of cytokines (interleukins 1 and 8 \[IL-1, IL-8\] and granulocyte macrophage-colony stimulating factor \[GM-CSF\] ) than those from normals. Thus, it is likely that LPS enhances allergen-induced inflammation and that allergic asthmatics are more sensitive to the effects of LPS. Preliminary data show that exposure to low levels (250 ng/m3) of LPS at risk for four hours enhances both immediate responsiveness to inhaled allergen and allergen-induced eosinophils as observed in induced sputum. In the nasal airways of allergics, a single dose of 1,000 nanograms of LPS enhances polymorphonuclear leukocyte influx associated with allergen challenge. This latter finding also correlates well with baseline IL-8 and ECP levels, suggesting that constitutive airway inflammation enhances response to these stimuli.
DESIGN NARRATIVE:
The effect of endotoxin LPS (5,000 nanograms) is compared on airway inflammation and methacholine response and lung function in normals and asthmatics; the effect of LPS (500 nanograms) is compared on allergen-induced reactivity and inflammatory cell influx following LPS exposure (5,000 nanograms) in asthmatics, likely as a result of decreasing baseline inflammation. To examine potential cellular mediation of the effect of LPS in asthma, cytokine secretion of mononuclear cells to LPS of subjects responding to LPS (or those in whom LPS enhance response to allergen) is compared to those who did not respond. In vitro monocyte and in vivo airway responses of asthmatics who are responsive and non-responsive is compared to baseline sputum and nasal lavage fluid IL-8 and ECP to determine if either in vitro monocyte responses or IL-8 and ECP in readily obtained airway fluids may serve as biomarkers of LPS responsiveness and might be used as a marker for a LPS-response phenotype in humans for future mechanistic and intervention studies. Finally, practical data on the effect of LPS in asthmatics (at levels found in typical work settings) and the ability of standard anti-inflammatory therapy to protect asthmatic workers unavoidable exposed to LPS will be obtained.
The study was renewed in 2001 and continues through December, 2005.
Conditions
See the medical conditions and disease areas that this research is targeting or investigating.
Eligibility Criteria
Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.
Inclusion Criteria
MALE
No
Sponsors
Meet the organizations funding or collaborating on the study and learn about their roles.
National Heart, Lung, and Blood Institute (NHLBI)
NIH
University of North Carolina, Chapel Hill
OTHER
Responsible Party
Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.
David B. Peden, MD
Professor of Pediatrics
Principal Investigators
Learn about the lead researchers overseeing the trial and their institutional affiliations.
David Peden
Role:
University of North Carolina
References
Explore related publications, articles, or registry entries linked to this study.
Alexis N, Eldridge M, Reed W, Bromberg P, Peden DB. CD14-dependent airway neutrophil response to inhaled LPS: role of atopy. J Allergy Clin Immunol. 2001 Jan;107(1):31-5. doi: 10.1067/mai.2001.111594.
Eldridge MW, Peden DB. Airway response to concomitant exposure with endotoxin and allergen in atopic asthmatics. J Toxicol Environ Health A. 2000 Sep 15;61(1):27-37. doi: 10.1080/00984100050116762.
Eldridge MW, Peden DB. Allergen provocation augments endotoxin-induced nasal inflammation in subjects with atopic asthma. J Allergy Clin Immunol. 2000 Mar;105(3):475-81. doi: 10.1067/mai.2000.104552.
Alexis NE, Peden DB. Blunting airway eosinophilic inflammation results in a decreased airway neutrophil response to inhaled LPS in patients with atopic asthma: a role for CD14. J Allergy Clin Immunol. 2001 Oct;108(4):577-80. doi: 10.1067/mai.2001.118511.
Alexis NE, Eldridge MW, Peden DB. Effect of inhaled endotoxin on airway and circulating inflammatory cell phagocytosis and CD11b expression in atopic asthmatic subjects. J Allergy Clin Immunol. 2003 Aug;112(2):353-61. doi: 10.1067/mai.2003.1651.
Alexis NE, Becker S, Bromberg PA, Devlin R, Peden DB. Circulating CD11b expression correlates with the neutrophil response and airway mCD14 expression is enhanced following ozone exposure in humans. Clin Immunol. 2004 Apr;111(1):126-31. doi: 10.1016/j.clim.2003.12.002.
Alexis NE, Lay JC, Almond M, Peden DB. Inhalation of low-dose endotoxin favors local T(H)2 response and primes airway phagocytes in vivo. J Allergy Clin Immunol. 2004 Dec;114(6):1325-31. doi: 10.1016/j.jaci.2004.09.002.
Other Identifiers
Review additional registry numbers or institutional identifiers associated with this trial.
5094
Identifier Type: -
Identifier Source: org_study_id
More Related Trials
Additional clinical trials that may be relevant based on similarity analysis.