T cells in sputum of asthmatic patients are activated independently of disease severity or control

Background: T cells play an important role in bronchial asthma. Although airway CD4+ T cells have been extensively studied previously, there are hardly any studies relating CD8+ T cell activation and disease symptoms. Objectives: The aim of this study was to analyse the association between T cell activation in induced sputum T cells and asthma severity and control; and to evaluate T cell subpopulations in the same subgroups. Methods: Fifty allergic asthmatic patients were recruited and lung function testing was performed. Airway cells were obtained by sputum induction via inhalation of hypertonic saline solution. CD3, CD4, CD8, CD28, CD25 and CD69 were studied by flow cytometry in whole induced sputum and peripheral blood cells. Results: Total induced sputum T cells and CD8+ T cells had a higher relative percentage of the activation markers CD25 and CD69 in comparison with peripheral blood. In sputum, the relative percentage of CD25 was higher in CD4+ T cells when compared to CD8+ T cells and the reverse was true regarding CD69. However, neither disease severity nor control were associated with the relative percentage of CD25 or CD69 expression on T cells in sputum. Conclusions: Both CD4+ and CD8+ T cells are activated in the lungs and peripheral blood of asthmatic patients. However, with the possible exception of CD69+ CD8+ T lymphocytes in the sputum, there is no association between T cell activation phenotype in the target organ and disease severity or control (AU)

Demographic, laboratory and clinical characterisation of adult portuguese asthmatic patients / Caracterızacıón demográfıca, analítıca y clínıca de pacıentes asmátıcos adultos portugueses

Background: Asthma is a heterogeneous chronic inflammatory condition characterised by reversible airway obstruction and hyperresponsiveness associated with underlying bronchial inflammation and structural changes. It represents an increasing health problem and is a huge burden on the patients, their families and society. The aim of the study was to characterise the adult asthmatic population attending a Hospital Allergy Clinic between the years of 2003 and 2006. Methods: Clinical files from the Allergy Outpatient Clinic of Cova da Beira Hospital were sequentially studied. The total population analysed included 335 female and 130 male asthmatic patients. Bronchial asthma was characterised by clinical history, skin prick testing to aeroallergens, determination of total and specific IgE and lung function testing, and classified according to international guidelines. Results: Of the patients studied, 70 % had allergic asthma, and 30 % had non-allergic asthma. When compared to allergic asthma, non-allergic asthma was more frequently associated with older age, perennial symptoms and female gender. More allergic than non-allergic asthma patients also had rhinitis and the reverse was true regarding drug allergy and oesophageal reflux. Grass pollen and mites were the major sensitisers for allergic asthmatics. The sensitisation profile was significantly different between urban- and rural-based asthmatic patients regarding tree pollen, fungi and moulds. Conclusions: In this population, rhinitis was more frequently associated with allergic than with non-allergic asthma. The two types of asthma did not differ in clinical severity or changes in lung function. Sensitisation profiles were different between the urban and rural patients

Antecedentes: el asma es un estado inflamatorio crónico heterogéneo, caracterizado por la obstrucción reversible de las vías aéreas e hiperreactividad asociada con la subyacente inflamación bronquial y cambios estructurales. Representa un creciente problema de salud y es una gran carga para los pacientes, sus familias y la sociedad. El objetivo de este estudio ha sido caracterizar la población de asmáticos adultos atendidos en el Clínica de Alergia del Hospital entre los años 2003 y 2006. Métodos: se estudió la documentación de los pacientes asistidos en el Ambulatorio de la Clínica de Alergia del Hospital Cova da Beira. El total de población analizada comprende 335 mujeres y 130 hombres. El asma bronquial se diagnóstico por la historia clínica, las pruebas cutáneas con aeroalergenos, la determinación de IgE total y específica y la función pulmonar, clasificándolos de acuerdo con las guías internacionales. Resultados: de los pacientes estudiados, el 70% tenían asma alérgica, y el 30% asma no alérgica. Comparando ambos grupos, el asma no alérgica estuvo asociada con mayor frecuencia con los pacientes de mayor edad, el género femenino y los síntomas perennes. Más pacientes con asma alérgica que no alérgica, también tenían rinitis, y lo contrario se observó con la alergia a medicamentos o el reflujo gastroesofágico. El polen de gramíneas y los ácaros del polvo fueron los alergenos más frecuentes en los asmáticos alérgicos. El perfil de sensibilización a polen de árboles, hongos y ácaros, fue significativamente distinto en los pacientes de la ciudad y los del área rural. Conclusiones: en esta población, la rinitis fue más frecuentemente asociada con el asma alérgica. Los dos tipos de asma no difieren en cuanto a la graveada o los cambios en la función pulmonar. Los perfiles de sensibilización fueron diferentes en el área urbana y en la rural

Functional and phenotypic characterization of CD8+CD28+ and CD28­ T cells in atopic individuals sensitized to Dermatophagoides pteronyssinus / Caracterización funcional y fenotípica de las células CD8+CD28+ y CD28¯ en individuos atópicos sensibilizados a Dermatophagoides pteroyissinus

Background: CD8+ T suppressor cells may play a role in immunoregulation. Recent studies have characterized this population by the lack of the CD28 molecule. These CD8+CD28– T cells differ phenotypically and functionally from CD8 + CD28 + T cells. Little is known about CD8 + CD28– cells in atopy. Our aim was to analyze the phenotype and functional properties of CD8 + CD28–T cells in atopic and non-atopic individuals. Methods: Peripheral blood mononuclear cells (PBMC) were obtained after density gradient centrifugation. CD8 + CD28– and CD8 + CD28 + T cells were isolated using immunomagnetic beads. Relative percentages of these cells and expression of several phenotypic markers were analyzed by flow cytometry. Proliferation was assessed by thymidine incorporation in isolated populations and in co-cultures with PBMC using Dermatophagoides pteronyssinusas stimulus. Cytokine synthesis was evaluated in culture supernatants by cytometric bead array. Results:The relative percentages of CD8+CD28– T cells and their phenotypic expression in atopic and non-atopic volunteers were not significantly different. However, CD8 + CD28– T cells showed greater proliferation than did CD8+CD28+ T cells when stimulated with D. pteronyssinus, although cytokine synthesis patterns were similar. CD8+CD28– co-cultures with PBMC showed greater proliferation than CD8+CD28+ T cell co-cultures, but cytokine synthesis patterns were not different. Conclusions: Our data confirm phenotypic and functional differences between CD28+ and CD28– T cells, irrespective of atopic status. Purified human CD8+CD28– T cells, freshly isolated from peripheral blood, do not have suppressor properties on allergen-specific proliferation or on cytokine synthesis in PBMC

Antecedentes: Células T CD8+ supresoras pueden tener un papel en inmunoregulación. Estudios recientes han demonstrado la falta de expresión de la molécula CD28 en esta población. Estas células T CD28− son diferentes fenotipica y funcionalmente de las células T CD28+. Se sabe muy poco de las células T CD8+CD28− en atopia. Nuestro objectivo ha sido analisar el fenótipo y función de células T CD8+CD28− en individuos atópicos y no atópicos. Métodos: Células mononucleares de la sangre periférica (CMSP) fueron obtenidas por gradiente de densidad. Células T CD8+CD28− y CD28+ fueran aisladas con cuentas inmunomagnéticas. Sus porcentages relativos y la expresión de varios marcadores fenotípicos fueran analizados con citometria de flujo. La proliferación fue estudiada por incorporación de timidina en las poblaciones aisladas y en co-culturas con CMSP, con Der p como estímulo. La sintesis de citocinas fue evaluada en los sobrenadantes de culturas por CBA. Resultados: Los porcentages relativos de células T CD8+CD28− y su expresión fenotípica no fueran distinctas entre atópicos y no atópicos. Las células T CD8+CD28− proliferaran mas que las células CD28+ quando estimuladas con Der p, aunque los padrones de síntesis de citocinas fueran similares. Co-culturas de células T CD8+CD28− con CMSP proliferaran mas que las co-culturas de células T CD8+CD28+ con las mismas células, pero los padrones de sintesis de citocinas no fueran diferentes. Conclusiones: Nuestros resultados confirman diferencias fenotípicas y funcionales entre células T CD28+ y CD28−, independientemente de la atopia. Células T CD8+CD28− humanas recientemente aisladas de la sangre periférica, no presentan propiedades supresoras sobre la proliferación o la sintesis de citocinas induzidas por alergenos en CMSP