Acute Exacerbations of Chronic Obstructive Pulmonary Disease Identification of Biologic Clusters and Their Biomarkers
ABSTRACT Exacerbations of chronic obstructive pulmonary disease (COPD) are heterogeneous with respect to inflammation and etiology.
Investigate biomarker expression in COPD exacerbations to identify biologic clusters and determine biomarkers that recognize clinical COPD exacerbation phenotypes, namely those associated with bacteria, viruses, or eosinophilic airway inflammation.
Patients with COPD were observed for 1 year at stable and exacerbation visits. Biomarkers were measured in sputum and serum. Viruses and selected bacteria were assessed in sputum by polymerase chain reaction and routine diagnostic bacterial culture. Biologic phenotypes were explored using unbiased cluster analysis and biomarkers that differentiated clinical exacerbation phenotypes were investigated. Measurements and Main Results: A total of 145 patients (101 men and 44 women) entered the study. A total of 182 exacerbations were captured from 86 patients. Four distinct biologic exacerbation clusters were identified. These were bacterial-, viral-, or eosinophilic-predominant, and a fourth associated with limited changes in the inflammatory profile termed “pauciinflammatory.” Of all exacerbations, 55%, 29%, and 28% were associated with bacteria, virus, or a sputum eosinophilia. The biomarkers that best identified these clinical phenotypes were sputum IL-1β, 0.89 (area under receiver operating characteristic curve) (95% confidence interval [CI], 0.83–0.95); serum CXCL10, 0.83 (95% CI, 0.70–0.96); and percentage peripheral eosinophils, 0.85 (95% CI, 0.78–0.93), respectively.
The heterogeneity of the biologic response of COPD exacerbations can be defined. Sputum IL-1β, serum CXCL10, and peripheral eosinophils are biomarkers of bacteria-, virus-, or eosinophil-associated exacerbations of COPD. Whether phenotype-specific biomarkers can be applied to direct therapy warrants further investigation.
SourceAvailable from: Bryan E Hoffman[Show abstract] [Hide abstract]
ABSTRACT: The p38 mitogen-activated protein kinase (MAPK) intracellular signaling pathway responds to a variety of extracellular stimuli, including cytokines, Toll-like receptor agonists, and components of cigarette smoke to influence the expression of proinflammatory mediators. Activation of p38 MAPK is increased within the lungs of chronic obstructive pulmonary disease (COPD) patients. In clinical trials, treatment of COPD patients with p38 MAPK inhibitors has been shown to reduce systemic inflammation plasma biomarkers C-reactive protein (CRP) and fibrinogen. As CRP and fibrinogen have been associated with poor clinical outcomes in COPD patients, such as mortality, exacerbation, and hospitalization, we analyzed gene expression data from COPD subjects treated with dilmapimod with the aim of understanding the effects of p38 MAPK inhibition on the inflammatory genome of immune cells within the systemic circulation. Whole blood and induced sputum samples were used to measure mRNA levels by gene array and PCR. Pathway and network analysis showed STAT1, MMP-9, CAV1, and IL-1β as genes regulated by dilmapimod that could also influence fibrinogen levels, while only IL-1β was identified as a gene regulated by dilmapimod that could influence CRP levels. This suggests that p38 MAPK inhibits specific inflammatory pathways, leading to to differential effects on CRP and fibrinogen levels in COPD patients.02/2015; 3(1). DOI:10.1002/prp2.94
[Show abstract] [Hide abstract]
ABSTRACT: Bronchial asthma (BA) and Allergic rhinitis (AR) are common clinical problems encountered in day to day practice, where inhalational corticosteroids (ICS) or intranasal steroids (INS) are the mainstay of treatment. Iatrogenic Cushing syndrome (CS) is a well known complication of systemic steroid administration. ICS /INS were earlier thought to be safe, but now more and more number of case reports of Iatrogenic Cushing syndrome have been reported, especially in those who are taking cytochrome P450 (CYP 450) inhibitors. Comparing to the classical clinical features of spontaneous Cushing syndrome, iatrogenic Cushing syndrome is more commonly associated with osteoporosis, increase in intra-ocular pressure, benign intracranial hypertension, aseptic necrosis of femoral head and pancreatitis, where as hypertension, hirsuitisum and menstrual irregularities are less common. Endocrine work up shows low serum cortisol level with evidence of HPA (hypothalamo-pituitary-adrenal) axis suppression. In all patients with features of Cushing syndrome with evidence of adrenal suppression always suspect iatrogenic CS. Since concomitant administration of cytochrome P450 inhibitors in patients on ICS/INS can precipitate iatrogenic CS, avoidance of CYP450 inhibitors, its dose reduction or substitution of ICS are the available options. Along with those, measures to prevent the precipitation of adrenal crisis has to be taken. An update on ICS-/INS- associated iatrogenic CS and its management is presented here.The Open Respiratory Medicine Journal 01/2014; 8(1):74-84. DOI:10.2174/1874306401408010074
[Show abstract] [Hide abstract]
ABSTRACT: Acute lung injury (ALI) is a severe disease characterized by alveolar neutrophilia, with limited treatment options and high mortality. Experimental models of ALI are key in enhancing our understanding of disease pathogenesis. Lipopolysaccharide (LPS) derived from gram positive bacteria induces neutrophilic inflammation in the airways and lung parenchyma of mice. Efficient pulmonary delivery of compounds such as LPS is, however, difficult to achieve. In the approach described here, pulmonary delivery in mice is achieved by challenge to aerosolized Pseudomonas aeruginosa LPS. Dissolved LPS was aerosolized by a nebulizer connected to compressed air. Mice were exposed to a continuous flow of LPS aerosol in a Plexiglas box for 10 min, followed by 2 min conditioning after the aerosol was discontinued. Tracheal intubation and subsequent bronchoalveolar lavage, followed by formalin perfusion was next performed, which allows for characterization of the sterile pulmonary inflammation. Aerosolized LPS generates a pulmonary inflammation characterized by alveolar neutrophilia, detected in bronchoalveolar lavage and by histological assessment. This technique can be set up at a small cost with few appliances, and requires minimal training and expertise. The exposure system can thus be routinely performed at any laboratory, with the potential to enhance our understanding of lung pathology.