Human Lung Responses to Respiratory Pathogens

• ClinicalTrials.gov Identifier: NCT01967628
• Recruitment Status: Completed
• First Posted: October 23, 2013
• Results First Posted: March 29, 2018
• Last Update Posted: March 29, 2018
• Sponsor: University of Iowa
• Collaborator: National Institute of Allergy and Infectious Diseases (NIAID)
• Information provided by (Responsible Party): Alicia Gerke, University of Iowa

Study Description

Brief 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.

Condition or disease	Intervention/treatment	Phase
Respiratory Infection	Dietary Supplement: Vitamin D3 (cholecalciferol); Dietary Supplement: Placebo Sugar Pill	Phase 1; Phase 2

Study Design

• Study Type: Interventional (Clinical Trial)
• Actual Enrollment: 98 participants
• Allocation: Randomized
• Intervention Model: Single Group Assignment
• Masking: Triple (Participant, Care Provider, Investigator)
• Primary Purpose: Basic Science
• Official Title: Human Lung Responses to Respiratory Pathogens
• Study Start Date: June 2007
• Actual Primary Completion Date: July 2010
• Actual Study Completion Date: October 2010

Arms and Interventions

Arm	Intervention/treatment
Experimental: Vitamin D3 (cholecalciferol); Vitamin D3 (1000 international units) daily for 3 months.	Dietary Supplement: Vitamin D3 (cholecalciferol)
Placebo Comparator: Sugar capsule; Placebo comparator made of sugar in a capsule	Dietary Supplement: Placebo Sugar Pill

Outcome Measures

Primary Outcome Measures :

1. Antimicrobial Activity by Airway Surface Liquid (ASL) as Measured by Relative Light Units (RLU) [ Time Frame: 3 months ]
   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

Eligibility Criteria

• Ages Eligible for Study: 18 Years to 60 Years (Adult)
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

Criteria

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

Contacts and Locations

Locations

United States, Iowa

University of Iowa

Iowa City, Iowa, United States, 52242

Sponsors and Collaborators

University of Iowa

National Institute of Allergy and Infectious Diseases (NIAID)

Investigators

• Principal Investigator: Alicia K Gerke, MD; University of Iowa

More Information

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):

Vargas Buonfiglio LG, Cano M, Pezzulo AA, Vanegas Calderon OG, Zabner J, Gerke AK, Comellas AP. Effect of vitamin D(3) on the antimicrobial activity of human airway surface liquid: preliminary results of a randomised placebo-controlled double-blind trial. BMJ Open Respir Res. 2017 Jun 4;4(1):e000211. doi: 10.1136/bmjresp-2017-000211. eCollection 2017.

Gerke AK, Pezzulo AA, Tang F, Cavanaugh JE, Bair TB, Phillips E, Powers LS, Monick MM. Effects of vitamin D supplementation on alveolar macrophage gene expression: preliminary results of a randomized, controlled trial. Multidiscip Respir Med. 2014 Mar 26;9(1):18. doi: 10.1186/2049-6958-9-18.

• Responsible Party: Alicia Gerke, Assistant Professor, University of Iowa
• ClinicalTrials.gov Identifier: NCT01967628
• Other Study ID Numbers: DMID 06-0003; N01AI30040-11-0-0 ( U.S. NIH Grant/Contract )
• First Posted: October 23, 2013
• Results First Posted: March 29, 2018
• Last Update Posted: March 29, 2018
• Last Verified: February 2018

Keywords provided by Alicia Gerke, University of Iowa:

Vitamin D; Respiratory infection; Innate immunity

Additional relevant MeSH terms:

Respiratory Tract Infections; Infections; Respiratory Tract Diseases; Vitamin D; Cholecalciferol; Vitamins; Micronutrients; Physiological Effects of Drugs; Bone Density Conservation Agents; Calcium-Regulating Hormones and Agents