Primary Outcome Measures:
- Cytokine production (TNF-alpha, IL-6, IL-8, IL-10, IL-1RA, G-CSF, IL-1B, MCP-1). [ Time Frame: This is a cross-sectional study with no follow-up period. Therefore the study outcomes were measured at the baseline visit (Time = day 0) ]
A whole blood stimulation assay was performed on blood samples from study participants. The whole blood was stimulated using several pathogen-associated molecular patterns that were agonists to seven different TLR receptors: 1) Pam3SCK4, 2) Zymosan, 3) FSL-1, 4) LPS, 5) flagellin, 6) R848. After stimulation with the PAMP, the cytokine levels (TNF-alpha, IL-6, IL-8, IL-10, IL-1RA, G-CSF, IL-1B, and MCP-1) were measured and the cytokine level results are in picograms per liter. Note, there is no treatment in this observational non-interventional trial. Therefore the multiple cytokine levels for each patient will not be aggregated or summarized into one measure. This study was a small pilot study and the results are exploratory.
The airways of COPD patients are often colonized with bacteria leading to increased airway inflammation. This study sought to determine whether systemic cytokine responses to microbial pathogen-associated molecular patterns (PAMPs) are increased among subjects with severe COPD.
In an observational cross-sectional study of COPD subjects, PAMP-induced cytokine responses were measured in whole blood ex vivo. We used PAMPs derived from microbial products recognized by TLR 1, 2, 4, 5, 6, 7, and 8. Patterns of cytokine response to PAMPs were assessed using hierarchical clustering. One-sided t-tests were used to compare PAMP-induced cytokine levels in blood from patients with and without severe COPD, and for subjects with and without chronic bronchitis.