NCT01967628

Human Lung Responses to Respiratory Pathogens

• Status: Completed
• Phase: Phase 1 / Phase 2
• Study type: Interventional
• Enrollment: 98 (actual)
• Sponsor: University of Iowa · Academic / Other
• Sex: All
• Age: 18 Years – 60 Years
• Healthy volunteers: Accepted

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.

Conditions

• Respiratory Infection

Interventions

Type	Name	Description
DIETARY_SUPPLEMENT	Vitamin D3 (cholecalciferol)
DIETARY_SUPPLEMENT	Placebo Sugar Pill

Timeline

• Start date: 2007-06-01
• Primary completion: 2010-07-01
• Completion: 2010-10-01
• First posted: 2013-10-23
• Last updated: 2018-03-29
• Results posted: 2018-03-29

Locations

1 site across 1 country: United States