Deborah Miotto

The C-C chemokine receptors CCR4 and CCR8 identify airway T cells of allergen-challenged atopic asthmatics

In vitro polarized human Th2 cells preferentially express the chemokine receptors CCR3, CCR4, and CCR8 and migrate to their ligands: eotaxin, monocyte-derived chemokine (MDC), thymus- and activation-regulated chemokine (TARC), and I-309. We have studied the expression of chemokines and chemokine receptors in the airway mucosa of atopic asthmatics. Immunofluorescent analysis of endobronchial biopsies from six asthmatics, taken 24 hours after allergen challenge, demonstrates that virtually all T cells express IL-4 and CCR4. CCR8 is coexpressed with CCR4 on 28% of the T cells, while CCR3 is expressed on eosinophils but not on T cells. Expression of the CCR4-specific ligands MDC and TARC is strongly upregulated on airway epithelial cells upon allergen challenge, suggesting an involvement of this receptor/ligand axis in the regulation of lymphocyte recruitment into the asthmatic bronchi. In contrast to asthma, T cells infiltrating the airways of patients with chronic obstructive pulmonary disease and pulmonary sarcoidosis produce IFN-gamma and express high levels of CXCR3, while lacking CCR4 and CCR8 expression. These data support the role of CCR4, of its ligands MDC and TARC, and of CCR8 in the pathogenesis of allergen-induced late asthmatic responses and suggest that these molecules could be considered as targets for therapeutic intervention.

Eotaxin and monocyte chemotactic protein-4 mRNA expression in small airways of asthmatic and nonasthmatic individuals

BACKGROUND Although an eosinophilic infiltrate has been observed in the small airways of asthmatic individuals, the mechanisms responsible for cellular recruitment in the lung periphery remain to be clarified. Eotaxin and monocyte chemotactic protein (MCP)-4 are 2 eosinophil-associated chemokines shown to be upregulated at sites of allergic inflammation. However, their expression within the small airways of asthmatic individuals remains to be elucidated. OBJECTIVE We sought to determine the expression of eotaxin and MCP-4 in the peripheral airways and parenchyma of lungs of subjects with asthma and to assess their relationship to the numbers of resident eosinophils. METHODS We examined surgically resected lung tissue from 6 asthmatic and 10 nonasthmatic subjects for the presence of eotaxin and MCP-4 mRNA by in situ hybridization. Chemokine mRNA expression was examined with respect to the numbers of eosinophils within the airways, as detected by immunocytochemistry for major basic protein. RESULTS Numbers of chemokine mRNA-positive cells were significantly increased in the large and small airways of asthmatic subjects compared with nonasthmatic subjects. Although eotaxin and MCP-4 mRNA were widely expressed in the lungs of subjects with asthma, their expression was particularly evident within the bronchial epithelium and inflammatory cells. In the airways of the asthmatic individuals, the expression of eotaxin mRNA was significantly correlated to the numbers of eosinophils present. CONCLUSION There is an increased expression of eotaxin and MCP-4 mRNA within the peripheral airways of lungs of asthmatic subjects, suggesting that these chemokines contribute to the small airways and peripheral lung inflammation in asthma.

Chronic obstructive pulmonary disease (COPD) and occupational exposures

Chronic obstructive pulmonary disease (COPD) is one of the leading causes of morbidity and mortality in both industrialized and developing countries.Cigarette smoking is the major risk factor for COPD. However, relevant information from the literature published within the last years, either on general population samples or on workplaces, indicate that about 15% of all cases of COPD is work-related.Specific settings and agents are quoted which have been indicated or confirmed as linked to COPD. Coal miners, hard-rock miners, tunnel workers, concrete-manufacturing workers, nonmining industrial workers have been shown to be at highest risk for developing COPD.Further evidence that occupational agents are capable of inducing COPD comes from experimental studies, particularly in animal models.In conclusion, occupational exposure to dusts, chemicals, gases should be considered an established, or supported by good evidence, risk factor for developing COPD. The implications of this substantial occupational contribution to COPD must be considered in research planning, in public policy decision-making, and in clinical practice.

Predominant emphysema phenotype in chronic obstructive pulmonary disease patients

Patients with fixed airflow limitation are grouped under the heading of chronic obstructive pulmonary disease (COPD). The authors investigated whether COPD patients have distinct functional, radiological and sputum cells characteristics depending on the presence or absence of emphysema. Twenty-four COPD outpatients, 12 with and 12 without emphysema on high-resolution computed tomography scan of the chest, were examined. Patients underwent chest radiography, pulmonary function tests and sputum induction and analysis. Subjects with documented emphysema had lower forced expiratory volume in one second (FEV1), FEV1/forced vital capacity ratio, and lower carbon monoxide diffusion constant (KCO), compared with subjects without emphysema. Chest radiograph score of emphysema was higher, chest radiograph score of chronic bronchitis was lower, and the number of sputum lymphocytes was increased in patients with emphysema, who also showed a negative correlation between KCO and pack-yrs. Chronic obstructive pulmonary disease patients with emphysema, documented by high-resolution computed tomography scan, have a different disease phenotype compared with patients without emphysema. Identification of chronic obstructive pulmonary disease-related phenotypes may improve understanding of the natural history and treatment of the disease.

Interleukin‐13 and ‐4 expression in the central airways of smokers with chronic bronchitis

The aim of this study was to determine whether the T‐helper 2‐type cytokines interleukin (IL)‐13 and ‐4 are involved in mucus hypersecretion, the hallmark of chronic bronchitis (CB). Surgical specimens were examined from 33 subjects undergoing lung resection for localised peripheral malignant pulmonary lesions: 21 smokers with symptoms of CB, 10 asymptomatic smokers (AS) and two nonsmokers with normal lung function. The number of IL‐4 and ‐13 positive (+) cells in the central airways was quantified. To better assess the cytokine profile, a count was also made of IL‐5+ and interferon (IFN)‐γ+ cells. Compared to AS, the CB group had an increased number of IL‐13+ and ‐4+ cells in the bronchial submucosa, while the number of IL‐5+ and IFN‐γ+ cells were similar in all the groups. No significant associations were found between the number of cells expressing IL‐13 or ‐4 and the number of inflammatory cells. Double labelling showed that 13.2 and 12.9% of IL‐13+ cells were also CD8+ and CD4+, whereas 7.5 and 5% of IL‐4+ cells were CD8+ and CD4+, respectively. In conclusion, T‐helper‐2 and ‐1 protein expression is present in the central airways of smokers and interleukin‐4 and ‐13 could contribute to mucus hypersecretion in chronic bronchitis.

Expression of protease activated receptor-2 (PAR-2) in central airways of smokers and non-smokers.

Background: Protease activated receptor-2 (PAR-2) is a transmembrane G protein coupled receptor preferentially activated by trypsin and tryptase. The protease activated receptors play an important role in most components of injury responses including cell proliferation, migration, matrix remodelling, and inflammation. Cigarette smoking causes an inflammatory process in the central airways, peripheral airways, lung parenchyma, and adventitia of pulmonary arteries. Methods: To quantify the expression of PAR-2 in the central airways of smokers and non-smokers, surgical specimens obtained from 30 subjects undergoing lung resection for localised pulmonary lesions (24 with a history of cigarette smoking and six non-smoking control subjects) were examined. Central airways were immunostained with an antiserum specific for PAR-2 and PAR-2 expression was quantified using light microscopy and image analysis. Results: PAR-2 expression was found in bronchial smooth muscle, epithelium, glands, and in the endothelium and smooth muscle of bronchial vessels. PAR-2 expression was similar in the central airways of smokers and non-smokers. When smokers were divided according to the presence of symptoms of chronic bronchitis and chronic airflow limitation, PAR-2 expression was increased in smooth muscle (median 3.8 (interquartile range 2.9–5.8) and 1.4 (1.07–3.4) respectively); glands (33.3 (18.2–43.8) and 16.2 (11.5–22.2), respectively); and bronchial vessels (54.2 (48.7–56.8) and 40.0 (36–40.4), respectively) of smokers with symptoms of chronic bronchitis with normal lung function compared with smokers with chronic airflow limitation (COPD), but the increase was statistically significant (p<0.005) only for bronchial vessels. Conclusions: PAR-2 is present in bronchial smooth muscle, glands, and bronchial vessels of both smokers and non-smokers. An increased expression of PAR-2 was found in bronchial vessels of patients with bronchitis compared with those with COPD.

Increased expression of major basic protein (MBP) and interleukin-5(IL-5) in middle ear biopsy specimens from atopic patients with persistent otitis media with effusion.

BACKGROUND: Molecular biologic evidence to support an etiologic role for allergy in the pathogenesis of persistent otitis media with effusion (OME) is lacking. OBJECTIVE: The goal of this article was to document expression of allergy-associated Th-2-type cytokines and inflammatory cells in the middle ear mucosa of children with persistent OME. METHODS: With immunocytochemistry (CDS, major basic protein) and in situ hybridization (interleukin-5 mRNA), middle ear biopsy specimens from 7 children with persistent OME were stained. Nonatopic stapedectomy patients with no history of otitis media served as controls (n = 7). RESULTS: There was a statistically significant (P < 0.05) difference in expression of CDS, major basic protein, and interleukin-5 between experimental and control subjects. All 8 OME patients proved to be atopic by ELISA testing. CONCLUSIONS: Type I allergy involving a Th-2-type cytokine and cellular profile may be a contributing factor in the persistence of OME in atopic children. SIGNIFICANCE: The middle ear may serve as a target organ for allergic inflammation, suggesting that appropriate allergy management may be a useful adjunct to the management of OME.

Macrophage expression of interleukin-10 is a prognostic factor in nonsmall cell lung cancer.

Interleukin (IL)-10 is expressed in many solid tumours and plays an ambiguous role in controlling cancer growth and metastasis. In order to determine whether IL-10 is involved in tumour progression and prognosis in nonsmall cell lung cancer (NSCLC), IL-10 expression in tumour cells and tumour-associated macrophages (TAMs) and its associations, if any, with clinicopathological features were investigated. Paraffin-embedded sections of surgical specimens obtained from 50 patients who had undergone surgery for NSCLC were immunostained with an antibody directed against IL-10. TAMs and tumour cells positive for IL-10 were subsequently quantified. IL-10-positive TAM percentage was higher in patients with stage II, III and IV NSCLC, and in those with lymph node metastases compared with patients with stage I NSCLC. High IL-10 expression by TAMs was a significant independent predictor of advanced tumour stage, and thus was associated with worse overall survival. Conversely, IL-10 expression by tumour cells did not differ between stages II, III and IV and stage I NSCLC. In conclusion, interleukin-10 expression by tumour-associated macrophages, but not by tumour cells, may play a role in the progression and prognosis of nonsmall cell lung cancer. These results may be useful in the development of novel approaches for anticancer treatments.

Anti-gabaergic neuron autoantibodies in a patient with stiff-man syndrome and ataxia

We describe a patient with autoimmune insulin-dependent diabetes whose original symptoms of trunk stiffness and rigidity of the abdomen were followed three years later by a pancerebellar syndrome. An autoantibody (autoAb) against GABAergic neurons was found in the patients serum and cerebrospinal fluid (CSF); on Western blot, this autoAb recognized a 64-kDa antigen of cerebellar protein. The detection of this antibody in a case with ataxia suggests that a spectrum of different neurological diseases may be observed in patients harbouring anti-GABAergic neuron autoAb and supports the concept that factors other than autoAb contribute to the clinical presentation of these disorders.

CD8+ T cells expressing IL-10 are associated with a favourable prognosis in lung cancer.

The dual role of tumour-infiltrating macrophages and lymphocytes on nonsmall cell lung cancer (NSCLC) progression and prognosis may be due to the differential activity of their phenotypes. To investigate the impact of inflammatory cells on NSCLC, we first quantified the number of macrophages (CD68+) and lymphocytes (CD8+ and CD4+) and the percentage of CD8+ cells expressing IL-10 (CD8+/IL-10+) in tumour stroma and epithelium. Then, we evaluated the possible relationships between the numbers of these cells and the clinicopathological features and the overall survival of patients. Paraffin-embedded sections of surgical specimens from 64 patients who had undergone surgery for NSCLC were immunostained with antibodies directed against CD68, CD4, CD8 and IL-10. The percentage of CD8+/IL-10+ cells was higher in cancer stroma of patients with stage I NSCLC than in those with stages II, III, and IV. High percentages of stromal CD8+/IL-10+ cells were associated with longer overall patient survival. In contrast, the number of CD68+, CD8+ and CD4+ cells did not differ between stage I NSCLC and stages II, III, and IV. In conclusion, the survival advantage of patients with stage I NSCLC may be related to the anti-tumour activity of the CD8+/IL-10+ cell phenotype.