@article {Mamessier:September 2008:0105-4538:1202,
	author = "Mamessier, E.",
	author = "Nieves, A.",
	author = "Lorec, A.-M.",
	author = "Dupuy, P.",
	author = "Pinot, D.",
	author = "Pinet, C.",
	author = "Vervloet, D.",
	author = "Magnan, A.",
	title = "T-cell activation during exacerbations: a longitudinal study in refractory asthma",
	journal = "Allergy",
	volume = "63",
	year = "September 2008",
	abstract = "Background:&#8194; <P></P>Asthma exacerbations represent the main source of costs and morbidity in asthma care, and drugs specifically designed to prevent exacerbations are needed. A prerequisite is to dispose of a precise knowledge of inflammatory events leading to exacerbations. Objective:&#8194; <P></P>To study T-cell activation during exacerbations from severe refractory asthmatics. Methods:&#8194; <P></P>Proportions of blood T-cell interleukin (IL)-13, interferon-&#947;, IL-4, IL-5, IL-10 production and of CD4+CD25+<SUP>high</SUP>CD62L+CD45RO+ [T regulatory (Treg)] cells were determined by flow cytometry. Blood cytokine mRNA was studied by reverse transcription-polymerase chain reaction and the respective protein levels were determined by cytokine beads array. Depletion of Treg cells was performed to study their activation. T-cell cytokines were detected in parallel in induced sputum. Results:&#8194; <P></P>At baseline, T helper 2 (Th2) cells were increased in asthmatics, whereas T helper 1 (Th1) and Treg T cells were decreased. T helper 2 cells increased before exacerbations, followed by Th1 cells, in blood and induced sputum, albeit Treg cells decreased in parallel with IL-10-producing T cells. Concordant results were found at the mRNA level. The suppressive activity of Treg cells was impaired during exacerbations compared to baseline. Conclusions:&#8194; <P></P>New insights are given into pathophysiology of asthma exacerbations: Although at baseline T-cell activation is Th2-biased, a mixed Th1&#47;Th2 activation occurs during exacerbations. The Treg cell deficiency found at baseline in SRA increases during exacerbations.",
	pages = "1202-1210(9)",
	url = "http://www.ingentaconnect.com/content/mksg/all/2008/00000063/00000009/art00011"
	doi = "doi:10.1111/j.1398-9995.2008.01687.x"
}