Platelet-activating factor- and leukotriene B4-induced release of lactoferrin from blood neutrophils of atopic and nonatopic individuals

A real - life observational pilot study to evaluate the effects of two-week treatment with montelukast in patients with chronic cough

Background

Different conditions make the proximal airways susceptible to tussigenic stimuli in the chronic cough (CC) syndrome. Leukotrienes can be implicated in the inflammatory mechanism at play in it. Montelukast is a selective cysteinyl-leukotriene receptor antagonist with proven effectiveness in patients with asthma. The aim of our real-life pilot study was to use montelukast to relieve cough symptoms in patients with CC allegedly due to the two frequent causes other than asthma – upper airway cough syndrome and gastroesophageal reflux (GER).

Methods

14 consecutive patients with CC were evaluated before and after 2 weeks of treatment with montelukast 10 mg daily. Cough was assessed by validated cough questionnaire. Questionnaires regarding the presence of gastroesophageal reflux were also completed. Cough reflex sensitivity to incremental doubling concentrations of citric acid and capsaicin was measured. Lung function, airway hyperresponsiveness and exhaled breath temperature (EBT), a non-invasive marker of lower airway inflammation, were evaluated to exclude asthma as an underlying cause. Thorough upper-airway examination was also conducted. Cell counts, eosinophil cationic protein (ECP), lactoferrin, myeloperoxidase (MPO) were determined in blood to assess systemic inflammation.

Results

Discomfort due to cough was significantly reduced after treatment (P < 0.001). Cough threshold for capsaicin increased significantly (P = 0.001) but not for citric acid. The values of lactoferrin and ECP were significantly reduced, but those of MPO rose. EBT and pulmonary function were not significantly affected by the treatment.

Conclusion

Patients with CC due to upper airway cough syndrome or gastroesophageal reflux (GER) but not asthma reported significant relief of their symptoms after two weeks of treatment with montelukast. ECP, lactoferrin, MPO altered significantly, highlighting their role in the pathological mechanisms in CC. Clinical trial ID at Clinicaltrials.gov is NCT01754220.

IL-17-producing peripheral blood CD177+ neutrophils increase in allergic asthmatic subjects

Background

A T helper cell (T_H) 17-biased response has been observed in patients with allergic asthma, particularly in those with neutrophil accumulation in the lung. Therefore, we sought to test the hypothesis that neutrophils might be an important source of interleukin (IL)-17 in allergic asthma.

Methods

Whole peripheral blood cells from non-asthmatic control subjects (n = 17) and patients with mild asthma (n = 7), moderate but persistent asthma (n = 4), or acute asthma (n = 6) were analyzed for IL-17A expression in CD177⁺ neutrophils. IL-17A expression was also analyzed in CD3⁺CD4⁺ and CD3⁺CD8⁺ lymphocyte populations. Asthmatic patients were classified as allergic to fungi, indoor allergens, or other allergens (e.g., pollen) based on a positive intradermal allergy test reaction.

Results

The percentage of CD177⁺ neutrophils in whole blood of asthmatic patients was higher than in healthy controls and highest in the moderate asthma group. Furthermore, the percentage of CD177⁺IL-17⁺ neutrophils was elevated in patients with mild asthma, whereas the CD4⁺ IL-17⁺ lymphocyte population was higher in asthmatic patients and highest in those with moderate but persistent asthma. We also found that the four patients that were allergic to fungi had the highest percentage of CD177⁺IL17⁺ neutrophils and CD8⁺IL17⁺ lymphocytes.

Conclusion

IL17⁺CD177⁺ Neutrophils increase in allergic asthma patients especially when allergic to fungi. This cell population, through release of IL-17, might be contributing during the initial phase asthmatic disease and/or during disease progression but its role has not yet been established.

The defect of the perforin granule system in cytotoxic T lymphocytes of atopic patients - are perforin reduction and hyperreleasability of clinical relevance? Zum Defekt des Perforin-Granulasystems zytotoxischer T-Lymphozyten bei Patienten mit Atopie - Sind Perforin-Reduktion und -Hyperreleasability klinisch relevant?

Perforin-containing lytic granules are secretory lysosomes of cytotoxic lymphocytes. They act as a negative regulator of activated T cells, control immunoglobulin production, contribute to the regulation of the TH1/TH2 balance, and occupy a central role in anti-viral defense mechanisms. This review focuses on recent evidence for a fundamental defect in the lymphocytic perforin system of atopic patients, namely perforin reduction and the hyperreleasability of perforin granules. These findings are set in relation to the immune imbalance in atopy, which is characterized by a weakly restrained proliferation of allergen-specific T and B cells, a predominance of Ttype-2 cytokines, and an increased susceptibility to cutaneous infections. In the context of the wellknown defect of secretory lysosomes in mast cells and keratinocytes of atopic patients, the possibility of a cell type-independent major pathological factor in atopy is discussed: pan-cellular reduction and hyperreleasability of secretory lysosomes.