Disturbed Cytokine Production at the Systemic Level in Difficult-to-Control Atopic Asthma: Evidence for Raised Interleukin-4 and Decreased Interferon-gamma Release following Lipopolysaccharide Stimulation.

in International Archives of Allergy & Immunology (2012), 158(1), 1-8

Background: Disturbed cytokine production is thought to govern inflammation in asthma, which, in its turn, may lead to uncontrolled disease. The aim of this study was to assess the relationship between ... [more ▼]

Background: Disturbed cytokine production is thought to govern inflammation in asthma, which, in its turn, may lead to uncontrolled disease. The aim of this study was to assess the relationship between cytokine production from blood leucocytes and the level of asthma control. Methods: We compared the production of interleukin (IL)-4, IL-6, IL-10, interferon (IFN)-gamma and tumour necrosis factor-alpha from peripheral blood leucocytes in non-atopic healthy subjects (n = 22), atopic non-asthmatics (n = 10), well-controlled asthmatics [Juniper asthma control questionnaire (ACQ) score <1.5; n = 20] and patients with uncontrolled asthma despite inhaled or oral corticoids (ACQ score >/=1.5; n = 20). Fifty microlitres of peripheral blood was incubated for 24 h with RPMIc, lipopolysaccharide (LPS; 1 ng/ml) or phytohaemagglutinin (1 mug/ml), and cytokines were measured by immunotrapping (ELISA). Results: Both controlled and uncontrolled asthmatics as well as atopic non-asthmatics spontaneously produced more IL-4 than non-atopic healthy subjects (p < 0.001). IL-4 production induced by LPS was significantly greater (p < 0.05) in both asthma groups compared to atopic non-asthmatics and non-atopic healthy subjects. By contrast, IFN-gamma release induced by LPS was lower in uncontrolled asthmatics than in non-atopic healthy subjects (p < 0.05) and controlled asthmatics (p < 0.05). IL-10 release after LPS was greater in uncontrolled asthmatics than in atopic non-asthmatics (p < 0.05). No difference was observed regarding other cytokines. Conclusion: Blood cells from patients with difficult-to-control atopic asthma display highly skewed Th2 cytokine release following LPS stimulation. [less ▲]

Local and systemic cellular inflammation and cytokine release in chronic obstructive pulmonary disease.

in Cytokine (2011), 56(2), 298-304

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a chronic airway inflammatory disease caused by repeated exposure to noxious gases or particles. It is now recognized that the disease also ... [more ▼]

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a chronic airway inflammatory disease caused by repeated exposure to noxious gases or particles. It is now recognized that the disease also features systemic inflammation. The purpose of our study was to compare airway and systemic inflammation in COPD to that seen in healthy subjects and to relate the inflammation with the disease severity. METHODS: Ninety-five COPD patients, encompassing the whole severity spectrum of the disease, were recruited from our outpatient clinic and rehabilitation center and compared to 33 healthy subjects. Induced sputum and blood samples were obtained for measurement of inflammatory cell count. Interleukin (IL)-4, IL-6, IL-10, TNF-alpha and IFN-gamma produced by 24h sputum and blood cell cultures were measured. RESULTS: Compared to healthy subjects, COPD exhibited a prominent airway neutrophilic inflammation associated with a marked IL-10, IL-6 and TNF-alpha release deficiency that contrasted with a raised IFN-gamma production. Neutrophilic inflammation was also prominent at blood level together with raised production of IFN-gamma, IL-10 and TNF-alpha. Furthermore, sputum neutrophilia correlated with disease severity assessed by GOLD stages. Likewise the extent of TNF-alpha release from blood cells also positively correlated with the disease severity but negatively with that of sputum cell culture. Blood release of TNF-alpha and IL-6 negatively correlated with body mass index. Altogether, our results showed a significant relationship between cellular marker in blood and sputum but poor relationship between local and systemic release of cytokines. CONCLUSIONS: COPD is characterized by prominent neutrophilic inflammation and raised IFN-gamma production at both bronchial and systemic level. Overproduction of TNF-alpha at systemic level correlates with disease severity and inversely with body mass index. [less ▲]

Exhaled nitric oxide thresholds associated with a sputum eosinophil count >=3% in a cohort of unselected patients with asthma.

in Thorax (2010), 65(12), 1039-1044

Background It has been claimed that exhaled nitric oxide (FeNO) could be regarded as a surrogate marker for sputum eosinophil count in patients with asthma. However, the FeNO threshold value that ... [more ▼]

Background It has been claimed that exhaled nitric oxide (FeNO) could be regarded as a surrogate marker for sputum eosinophil count in patients with asthma. However, the FeNO threshold value that identifies a sputum eosinophil count >/=3% in an unselected population of patients with asthma has been poorly studied. Methods This retrospective study was conducted in 295 patients with asthma aged 15-84 years recruited from the asthma clinic of University Hospital of Liege. Receiver-operating characteristic (ROC) curve and logistic regression analysis were used to assess the relationship between sputum eosinophil count and FeNO, taking into account covariates such as inhaled corticosteroids (ICS), smoking, atopy, age and sex. Results Derived from the ROC curve, FeNO >/=41 ppb gave 65% sensitivity and 79% specificity (AUC=0.777, p=0.0001) for identifying a sputum eosinophil count >/=3%. Using logistic regression analysis, a threshold of 42 ppb was found to discriminate between eosinophilic and non-eosinophilic asthma (p<0.0001). Patients receiving high doses of ICS (>/=1000 mug beclometasone) had a significantly lower FeNO threshold (27 ppb) than the rest of the group (48 ppb, p<0.05). Atopy also significantly altered the threshold (49 ppb for atopic vs 30 ppb for non-atopic patients, p<0.05) and there was a trend for a lower threshold in smokers (27 ppb) compared with non-smokers (46 ppb, p=0.066). Age and sex did not affect the relationship between FeNO and sputum eosinophilia. When combining all variables into the logistic model, FeNO (p<0.0001), high-dose ICS (p<0.05) and smoking (p<0.05) were independent predictors of sputum eosinophilia, while there was a trend for atopy (p=0.086). Conclusion FeNO is able to identify a sputum eosinophil count >/=3% with reasonable accuracy and thresholds which vary according to dose of ICS, smoking and atopy. [less ▲]

L'omalizumab (Xolair) dans le traitement de l'asthme allergique persistant severe.

in Revue Médicale de Liège (2009), 64(5-6), 313-7

L’asthme est une maladie chronique des voies aériennes. La plupart des asthmatiques ont une inflammation bronchique liée à un processus immunologique faisant intervenir les immunoglobulines E (IgE). En ... [more ▼]

L’asthme est une maladie chronique des voies aériennes. La plupart des asthmatiques ont une inflammation bronchique liée à un processus immunologique faisant intervenir les immunoglobulines E (IgE). En dépit des thérapeutiques existantes, les patients atteints d’asthme sévère ont une qualité de vie sérieusement altérée et présentent un risque élevé d’exacerbations graves pouvant parfois être fatales. L’omalizumab est un anticorps (Ac) monoclonal humanisé dirigé contre les IgE circulantes, interférant ainsi avec une des cascades moléculaires importantes dans la pathogénie de l’asthme. L’omalizumab a montré qu’il était capable d’améliorer la qualité de vie et de réduire la fréquence des exacerbations ainsi que le recours aux corticoïdes inhalés et systémiques. Selon les nouvelles recommandations de l’asthme du GINA 2006, cet agent biologique est indiqué dans l’asthme allergique persistant sévère. [less ▲]