Leukotriene B4 levels in sputum from asthma patients.

Poor asthma control is associated with increased airway neutrophils. Leukotriene B4 (LTB4) is a potent neutrophil chemoattractant. We examined the levels of LTB4 levels in the sputum of asthma patients and the relationship with disease severity.

Repeatability of induced sputum measurements in moderate to severe asthma.

Background: Novel therapies are being developed for patients with moderate to severe asthma. These patients may have neutrophilic airway inflammation. Induced sputum is commonly used as an endpoint in clinical trials of asthma therapies.

Inhibition of the asthmatic allergen challenge response by the CRTH2 antagonist OC000459.

CRTH2 (chemoattractant receptor expressed on T-helper (Th) type 2 cells) is a G-protein-coupled receptor expressed by Th2 lymphocytes and eosinophils that mediates prostaglandin (PG)D(2)-driven chemotaxis. We studied the efficacy of the oral CRTH2 antagonist OC000459 in steroid-naïve asthmatic patients. A randomised, double-blind, placebo-controlled, two-way crossover study of 16 days' treatment with OC000459 (200 mg twice daily) on the late (LAR) and early (EAR) asthmatic responses to bronchial allergen challenge was conducted, with 16 subjects completing the study.

A comparison of the clinical and induced sputum characteristics of early- and late-onset asthma.

Background: There are few studies describing the phenotype of late-onset asthma (LOA). We sought to investigate the clinical and induced sputum characteristics of patients with LOA.

Methods: Nineteen patients with LOA diagnosed after the age of 40 years and 19 patients with early-onset asthma (EOA) diagnosed before the age of 20 years were recruited.

T lymphocyte insensitivity to corticosteroids in chronic obstructive pulmonary disease.

Background: There are increased numbers of activated lymphocytes in the lungs of chronic obstructive pulmonary disease (COPD) patients. The clinical benefits of corticosteroids in COPD patients are limited. Our hypothesis is that lymphocytes play a role in this corticosteroid insensitivity.

Non-invasive phenotyping using exhaled volatile organic compounds in asthma.

Background: Breath volatile organic compounds (VOCs) may be useful for asthma diagnosis and phenotyping, identifying patients who could benefit from personalised therapeutic strategies. The authors aimed to identify specific patterns of breath VOCs in patients with asthma and in clinically relevant disease phenotypes.

Methods: Breath samples were analysed by gas chromatography-mass spectrometry.