This site became the new on June 19th. Learn more.
Show more Menu IMPORTANT: Listing of a study on this site does not reflect endorsement by the National Institutes of Health. Talk with a trusted healthcare professional before volunteering for a study. Read more... Menu IMPORTANT: Talk with a trusted healthcare professional before volunteering for a study. Read more... Menu
Give us feedback

Role of TLR4 in Environmental Asthma

This study has been completed.
Information provided by (Responsible Party):
John Sundy, Duke University Medical Center Identifier:
First received: May 2, 2008
Last updated: July 15, 2013
Last verified: July 2013
The overall goal of this project is to identify genes that are involved in the development of airflow obstruction and airway inflammation in asthmatics, and to determine whether polymorphisms in these differentially expressed genes predispose individuals to develop asthma. In this project, we hypothesize that polymorphisms of genes expressed by the airway epithelia in asthmatics following specific airway challenges predispose individuals to the development of asthma.

Condition Intervention Phase
Asthma Biological: Lipopolysaccharide endotoxin Phase 1

Study Type: Interventional
Study Design: Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Basic Science
Official Title: Role of TLR4 in Environmental Asthma

Further study details as provided by John Sundy, Duke University Medical Center:

Primary Outcome Measures:
  • Ascertain individuals homozygous, and heterozygous for mutant TLR4 genotype, along with wild types by recruitment of healthy screening subjects in the community. [ Time Frame: completed ]

Secondary Outcome Measures:
  • Assess the effect of TLR4 genotype on LPS endotoxin induced immune responses and assess the association of the LPS-induced immune response with LPS-induced airway responses. [ Time Frame: 24 hours ]

Enrollment: 855
Study Start Date: September 2001
Study Completion Date: April 2008
Primary Completion Date: August 2006 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Challenge

Experimental Challenge Challenge 1 saline 5000EU 10,000EU 20,000EU

Challenge 2 Saline 40,000EU 80,000EU

Biological: Lipopolysaccharide endotoxin

Delivered in nebulized form expressed in activity units(endotoxin units -EU).

Subjects receive each dose 30 min after completing the previous dose, dose duration is approximately 10 minutes:

Challenge One first saline then 5000 EU 10,000 EU 20,000 EU

Challenge 1 and 2 must be at least 2 weeks apart.

Challenge 2 Saline 40,000 EU 80,000 EU

Other Name: (CCRE)LPS endotoxin from E. Coli 0:113 maintained by NIH

  Show Detailed Description


Ages Eligible for Study:   18 Years to 40 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • vital signs within normal limits
  • negative methacholine challenge (non asthmatic)
  • normal PFT's, CXR, EKG
  • negative allergy skin tests (non atopic)
  • never cigarette smoker
  • no chronic illness
  • no daily meds except contraceptives
  • able and willing to sign informed consent
  • not an employee working for,or a student under the authority of the PI's

Exclusion Criteria:

  • allergic rhinitis past or present
  • chronic illness resulting in altered lung function
  • chronic daily medications
  • cigarette smoking
  • allergy to acetaminophen or albuterol
  • pregnant or nursing females
  • PFT results below cut off
  • Positive allergy skin test
  • Abnormal CXR or EKG
  • Positive methacholine challenge
  • Infection in the previous 2 weeks
  • Past or present allergen immunotherapy
  • Occupational exposure to hay or grain
  • Other medical or psychological conditions which, in the opinion of the PI, may create undue risk to the subject or interfere with the subject's ability to comply with protocol requirements.
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT00671892

United States, North Carolina
Duke University Medical Center
Durham, North Carolina, United States, 27710
Sponsors and Collaborators
John Sundy
Principal Investigator: John S Sundy, M.D., PhD. Duke University
  More Information

Responsible Party: John Sundy, Associate Professor of Medicine, Duke University Medical Center Identifier: NCT00671892     History of Changes
Other Study ID Numbers: 3030-07-8R5
12496-CP-007 ( Other Identifier: NIEHS )
Study First Received: May 2, 2008
Last Updated: July 15, 2013

Keywords provided by John Sundy, Duke University Medical Center:
LPS endotoxin

Additional relevant MeSH terms:
Bronchial Diseases
Respiratory Tract Diseases
Lung Diseases, Obstructive
Lung Diseases
Respiratory Hypersensitivity
Hypersensitivity, Immediate
Immune System Diseases processed this record on September 21, 2017