Human Lung Responses to Respiratory Pathogens

Respiratory Infection Clinical Trial

Official title:

Human Lung Responses to Respiratory Pathogens

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01967628
• Other study ID #: DMID 06-0003
• Secondary ID: N01AI30040-11-0-
• Status: Completed
• Phase: Phase 1/Phase 2
• First received: October 17, 2013
• Last updated: February 28, 2018
• Start date: June 2007
• Est. completion date: October 2010

Study information

• Verified date: February 2018
• Source: University of Iowa
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

For most individuals, the lung has a remarkable ability to deal with exposure to a variety of inhaled bacteria. Some individuals, however, do have recurrent bacterial infections, usually in the form of acute or chronic bronchitis and, in some instances, pneumonia. The reasons for this variability in bacterial infections between otherwise healthy subjects, between types of lung disease, and within the same type of lung disease are poorly understood.

Variability in susceptibility to bacterial infections is partially explained by differences in exposure to infectious agents, genetic susceptibility and innate (or early) immune responses. It is of interest that the incidence and severity of bacterial infections is greatest during the winter months. Other than viral infections, there are few variables that change with season. Vitamin D is one known immune modulator with a seasonal periodicity. The hypothesis of this study is that levels of vitamin D are an important determinant of the innate defense of the lung against inhaled bacteria. The investigators further postulate that vitamin D has effects on the innate immune function of both alveolar macrophages and lung epithelial cells.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 98
• Est. completion date: October 2010
• Est. primary completion date: July 2010
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 60 Years

Eligibility

Inclusion Criteria:

Signed informed consent form Age 18 - 60 Healthy nonsmoker, healthy smoker Forced expiratory volume in 1 second (for smokers) > 60% predicted.

Exclusion Criteria:

• Pregnant or breastfeeding

• Medications (with the exception of hormonal birth control, thyroid medication or prespecified over the counter medications), including multi-vitamins and any preparation that contains vitamin D

• Asthma

• Heart disease

• Diabetes

• Previous positive tuberculin skin test, or previous diagnosis of tuberculosis

• Recent respiratory tract infection

• History of multiple bouts of pneumonia

• Allergies to caines, atropine, or a history of adverse reaction to narcotics

• Other factors that increase the risk of bronchoscopy

• Evidence of acute bronchitis within the past 2 weeks

Related Conditions & MeSH terms

• Respiratory Infection
• Respiratory Tract Infections

Intervention

Dietary Supplement:
• Vitamin D3 (cholecalciferol)

• Placebo Sugar Pill

Locations

Country	Name	City	State
United States	University of Iowa	Iowa City	Iowa

Sponsors (2)

Lead Sponsor	Collaborator
University of Iowa	National Institute of Allergy and Infectious Diseases (NIAID)

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Antimicrobial Activity by Airway Surface Liquid (ASL) as Measured by Relative Light Units (RLU)	We investigated the effect of vitamin D3 supplementation on airway surface liquid antimicrobial activity using a bioluminescent bacterial challenge. We challenged airway surface liquid samples with bioluminescent bacteria and measured live bacteria by relative light units (RLU) after 2 minutes as a surrogate of antimicrobial activity. We interpreted a reduction in live bacteria after challenge in relative light units as increased antimicrobial activity	3 months