title: Participation of CD161(+) and invariant natural killer T cells in pediatric asthma exacerbations.
abstract: Asthma has been defined as a disease of chronic airway inflammation in which many cells and cellular products participate with variable degrees of airflow obstruction and hyperresponsiveness that lead to recurrent episodes of wheezing, breathlessness, chest tightness, and coughing.  Prominent among these cellular elements are two cell types referred to as the invariant natural killer T (iNKT) cells and a subpopulation of T cells expressing the molecule CD161, which are both thought to play a role in the pathogenesis of asthma. Although the presence of iNKT and other CD161(+)  cells in murine models has been associated with asthma, relatively few studies have been performed in the adult patient with asthma that have been often conflicting and even fewer studies are available in children. The present study was performed to investigate the peripheral blood frequencies  of iNKT and CD161(+) T cells in children with asthma. A total of 35 children, 19 stable asthmatic patients, 6 who had experienced an asthmatic attack within 24 hours and had not received any treatment, and 10 healthy controls, aged 6-12 years, were enrolled in the study. iNKT  and CD161(+) T-cell frequencies in blood were measured together with quantitative levels of IL-4 and interferon (IFN) γ using a cytofluorimetric approach. The results show that iNKT cells are increased in pediatric asthmatic patients undergoing exacerbations of asthma. These  cells also produced less IFN-γ and more IL-4 than children with stable asthma and in healthy control children. These results suggest that iNKT cells might participate in the development of the asthmatic exacerbations. The increased production of IL-4 in conjunction with the decrease  of IFN-γ may be mechanistically responsible, at least partially, for the heightening of the immunologic response leading to the asthmatic attack in children. Knowledge of these interactive mechanisms involving the iNKT cell and our understanding of its role in the exacerbation of asthma  hold great promise in the development of better diagnostic predictive markers of disease progression as well as new forms of therapeutic interventions.
authors: Departamento de Investigaciones Inmunológicas, Instituto de Diagnóstico y Referencia Epidemiológicos, Mexico City, Mexico.
authors: Juan C
authors: JC
authors: Carpio-Pedroza
authors: Gilberto
authors: G
authors: Vaughan
authors: Blanca E
authors: BE
authors: del Rio-Navarro
authors: Jaime M
authors: JM
authors: del Río-Chivardí
authors: Arely
authors: A
authors: Vergara-Castañeda
authors: Luis A
authors: LA
authors: Jiménez-Zamudio
authors: Amelia
authors: A
authors: Morales-Flores
authors: Guadalupe
authors: G
authors: Rodríguez-Moreno
authors: Karina
authors: K
authors: Ruiz-Tovar
authors: Salvador
authors: S
authors: Fonseca-Coronado
authors: Livia M
authors: LM
authors: Gonçalves Rossi
authors: Alejandro
authors: A
authors: Escobar-Gutiérrez
mesh_terms: D001249:Asthma / Q000276:immunology*; D015704:CD4 Antigens / Q000378:metabolism; D002469:Cell Separation; D002648:Child; D018450:Disease Progression; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism*; D015847:Interleukin-4 / Q000378:metabolism*; D008213:Lymphocyte Activation; D018655:Lymphocyte Count; D008297:Male; D055651:NK Cell Lectin-Like Receptor Subfamily B / Q000378:metabolism; D055611:Natural Killer T-Cells / Q000276:immunology*
chemical_list: D015704:CD4 Antigens; D055651:NK Cell Lectin-Like Receptor Subfamily B; D015847:Interleukin-4; D007371:Interferon-gamma