Persistence of rhinovirus RNA and IP-10 gene expression after acute asthma.

Background And Objective: Viral nucleic acid may be detected for up to 6 months after an acute asthma deterioration, but the pattern and consequences of viral persistence after acute asthma are incompletely understood. This study investigates the frequency of viral persistence after acute asthma, assesses viral infectivity and determines the host inflammatory responses to viral persistence.

Methods: Adults and children presenting to hospital with acute asthma and a confirmed respiratory virus infection were studied acutely and at recovery 4-6 weeks later by clinical evaluation and induced sputum for viral and inflammatory mediator detection.

Prospective assessment of protracted bacterial bronchitis: airway inflammation and innate immune activation.

Protracted bacterial bronchitis (PBB) is a common cause of paediatric chronic moist cough. PBB is defined as the presence of isolated chronic moist cough which resolves with antibiotic therapy within 2 weeks and an absence of pointers suggesting alternative diagnoses. Our aim was to describe the clinical profile and examine the airway cellularity and likely promoters of neutrophilic inflammation in the bronchoalveolar lavage (BAL) of children with PBB compared with chronic cough due to other causes and controls.

Reduced toll-like receptor 4 and substance P gene expression is associated with airway bacterial colonization in children.

Neuro-immune interactions are increasingly relevant to human health and disease. The neuropeptide Substance P also has antibacterial activity and bears similarities to the innate immune antibacterial defensins. This suggests possible co-regulation of neuropeptide and innate immune mediators.

Innate immune activation in neutrophilic asthma and bronchiectasis.

Background: The role of the innate immune system in the pathogenesis of asthma is unclear. Activation of innate immune receptors in response to bacterial lipopolysaccharide, viral infection and particulate matter triggers a pre-programmed inflammatory response, which involves interleukin (IL)8 and neutrophil influx. The inflammatory response in asthma is heterogeneous.

Virus infection in exacerbations of chronic obstructive pulmonary disease requiring ventilation.

Objectives: We aimed to characterise and quantify the incidence of common infectious agents in acute exacerbations of chronic obstructive pulmonary disease (COPD) requiring ventilation, with a focus on respiratory viruses.

Design: An epidemiological study conducted over 3 years.

Setting: A 12-bed intensive care unit (ICU).

Interleukin-10 gene expression in acute virus-induced asthma.

Rationale: Virus-induced asthma is characterized by marked neutrophil influx and eosinophil degranulation, suggesting a mode of immunopathogenesis different from that of allergen-induced asthma.

Objectives: This study compared induced sputum cytokine responses in subjects with severe asthma exacerbation and respiratory virus infection with those of patients with stable asthma, healthy control subjects, and virus-infected nonasthmatic subjects.

Methods: Subject infection status and pulmonary history were established on the basis of common cold and asthma questionnaires, and lung function and atopy tests were performed.