NCT01792232

Brief Summary

The investigators are investigating the effects of combined exposures to diesel exhaust and allergens on lung function and on the immune system. After exposing individuals to either filtered air or carefully controlled levels of diesel exhaust in our exposure chamber, The investigators will use a procedure called bronchoscopy (whereby a thin, flexible tube is passed down the throat and into the lungs) to place a small amount of allergen directly in the lung. 48h later, the bronchoscopy will be repeated so that samples can be collected from the lungs. After 1mo, the entire procedure will be repeated with the alternate exposure.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
18

participants targeted

Target at below P25 for not_applicable

Timeline
Completed

Started Oct 2011

Typical duration for not_applicable

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

October 1, 2011

Completed
1.1 years until next milestone

First Submitted

Initial submission to the registry

November 14, 2012

Completed
3 months until next milestone

First Posted

Study publicly available on registry

February 15, 2013

Completed
9 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

November 1, 2013

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

November 1, 2013

Completed
Last Updated

September 29, 2017

Status Verified

September 1, 2017

Enrollment Period

2.1 years

First QC Date

November 14, 2012

Last Update Submit

September 27, 2017

Conditions

Allergies

Keywords

Diesel exhaustAir pollutionAirway responsivenessAllergies

Outcome Measures

Primary Outcomes (1)

  • Allergen-specific IgE

    BAL IgE specific to the allergen used for allergen challenge will be assessed at 48 hrs, from the BAL, using immunocap assay

    48 hours

Secondary Outcomes (3)

  • Human immune response

    48 hours

  • Oxidative stress

    48 hours

  • Airway reactivity

    48 hours

Study Arms (4)

Filtered air

ACTIVE COMPARATOR

Exposure for 2 hours to filtered air followed by subject specific allergen placed in lung

Other: Allergen

Diesel exhaust

EXPERIMENTAL

Exposure for 2 hours to diesel exhaust followed by subject specific allergen placed in lung

Other: Allergen

Filtered air control

ACTIVE COMPARATOR

Exposure for 2 hours to filtered air followed by subject saline placed in lung

Other: Saline

Diesel exhaust control

ACTIVE COMPARATOR

Exposure for 2 hours to diesel exhaust followed by saline placed in lung

Other: Saline

Interventions

AllergenOTHER

Subject specific allergen is placed in the lungs on day 1 of each triad

Diesel exhaustFiltered air
SalineOTHER

Saline will be placed in the lung on day 1 of each triad

Diesel exhaust controlFiltered air control

Eligibility Criteria

Age19 Years - 49 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64)

You may qualify if:

  • Age between 19 and 49 years.
  • Non-smoking.
  • Positive skin prick test for at least one of: birch, grass, or dust

You may not qualify if:

  • Using inhaled corticosteroids
  • Pregnant or planning to be pregnant in the next 12 months / Breastfeeding
  • Usage of bronchodilators more than three times per week.
  • Co-morbidities (as assessed by the primary investigator)
  • Taking part in other studies
  • Unwilling to withhold bronchodilator, aspirin, anti-coagulant, antihistamine or decongestant medications or caffeine prior to testing procedures.
  • FEV1(Forced expiratory volume in one second) \< 70% predicted.
  • Allergy to lidocaine, fentanyl, midazolam or salbutamol.
  • Unstable asthma (i.e exacerbation in 2 weeks preceding testing)

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

University of British Columbia

Vancouver, British Columbia, V5Z 1M9, Canada

Location

Related Publications (11)

  • Saxon A, Diaz-Sanchez D. Air pollution and allergy: you are what you breathe. Nat Immunol. 2005 Mar;6(3):223-6. doi: 10.1038/ni0305-223. No abstract available.

    PMID: 15716966BACKGROUND

  • Rudell B, Ledin MC, Hammarstrom U, Stjernberg N, Lundback B, Sandstrom T. Effects on symptoms and lung function in humans experimentally exposed to diesel exhaust. Occup Environ Med. 1996 Oct;53(10):658-62. doi: 10.1136/oem.53.10.658.

    PMID: 8943829BACKGROUND

  • Diaz-Sanchez D, Tsien A, Fleming J, Saxon A. Combined diesel exhaust particulate and ragweed allergen challenge markedly enhances human in vivo nasal ragweed-specific IgE and skews cytokine production to a T helper cell 2-type pattern. J Immunol. 1997 Mar 1;158(5):2406-13.

    PMID: 9036991BACKGROUND

  • Fujieda S, Diaz-Sanchez D, Saxon A. Combined nasal challenge with diesel exhaust particles and allergen induces In vivo IgE isotype switching. Am J Respir Cell Mol Biol. 1998 Sep;19(3):507-12. doi: 10.1165/ajrcmb.19.3.3143.

    PMID: 9730879BACKGROUND

  • Hashimoto K, Ishii Y, Uchida Y, Kimura T, Masuyama K, Morishima Y, Hirano K, Nomura A, Sakamoto T, Takano H, Sagai M, Sekizawa K. Exposure to diesel exhaust exacerbates allergen-induced airway responses in guinea pigs. Am J Respir Crit Care Med. 2001 Nov 15;164(10 Pt 1):1957-63. doi: 10.1164/ajrccm.164.10.2011070.

    PMID: 11734452BACKGROUND

  • Carlsten, C., et al., Symptoms and perceptions in response to a controlled diesel exhaust exposure in healthy adults. Environmental Research, In Review

    BACKGROUND

  • Riedl MA, Diaz-Sanchez D, Linn WS, Gong H Jr, Clark KW, Effros RM, Miller JW, Cocker DR, Berhane KT; HEI Health Review Committee. Allergic inflammation in the human lower respiratory tract affected by exposure to diesel exhaust. Res Rep Health Eff Inst. 2012 Feb;(165):5-43; discussion 45-64.

    PMID: 22852485BACKGROUND

  • Carlsten C, Melen E. Air pollution, genetics, and allergy: an update. Curr Opin Allergy Clin Immunol. 2012 Oct;12(5):455-60. doi: 10.1097/ACI.0b013e328357cc55.

    PMID: 22885891BACKGROUND

  • Kramer MM, Hirota JA, Sood A, Teschke K, Carlsten C. Airway and serum adipokines after allergen and diesel exposure in a controlled human crossover study of atopic adults. Transl Res. 2017 Apr;182:49-60. doi: 10.1016/j.trsl.2016.11.001. Epub 2016 Nov 9.

    PMID: 27886976DERIVED

  • Hosseini A, Hirota JA, Hackett TL, McNagny KM, Wilson SJ, Carlsten C. Morphometric analysis of inflammation in bronchial biopsies following exposure to inhaled diesel exhaust and allergen challenge in atopic subjects. Part Fibre Toxicol. 2016 Jan 13;13:2. doi: 10.1186/s12989-016-0114-z.

    PMID: 26758251DERIVED

  • Carlsten C, Blomberg A, Pui M, Sandstrom T, Wong SW, Alexis N, Hirota J. Diesel exhaust augments allergen-induced lower airway inflammation in allergic individuals: a controlled human exposure study. Thorax. 2016 Jan;71(1):35-44. doi: 10.1136/thoraxjnl-2015-207399. Epub 2015 Nov 16.

    PMID: 26574583DERIVED

MeSH Terms

Conditions

Hypersensitivity

Interventions

AllergensSodium Chloride

Condition Hierarchy (Ancestors)

Immune System Diseases

Intervention Hierarchy (Ancestors)

AntigensBiological FactorsChloridesHydrochloric AcidChlorine CompoundsInorganic ChemicalsSodium Compounds

Study Officials

  • Christopher Carlsten, MD, MPH

    University of British Columbia

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
TRIPLE
Who Masked
PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
Purpose
BASIC SCIENCE
Intervention Model
CROSSOVER
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Principal Investigator

Study Record Dates

First Submitted

November 14, 2012

First Posted

February 15, 2013

Study Start

October 1, 2011

Primary Completion

November 1, 2013

Study Completion

November 1, 2013

Last Updated

September 29, 2017

Record last verified: 2017-09

Locations

CA(1)