PT - JOURNAL ARTICLE AU - Nathalie Freymond AU - Vincent Cottin AU - Chahéra Khouatra AU - Jean-Emmanuel Kahn AU - Nadia Sivova AU - Lionel Prin AU - Fanny Legrand AU - Jean-François Cordier TI - TCR rearrangement in patients with eosinophilic lung disease DP - 2011 Sep 01 TA - European Respiratory Journal PG - p1835 VI - 38 IP - Suppl 55 4099 - http://erj.ersjournals.com/content/38/Suppl_55/p1835.short 4100 - http://erj.ersjournals.com/content/38/Suppl_55/p1835.full SO - Eur Respir J2011 Sep 01; 38 AB - Background: Expansion of monoclonal population of T-cells with T-cell receptor (TCR) rearrangements and aberrant cell surface immunophenotype produce IL-5 and contribute to the pathophysiology of the lymphocytic variant of the hypereosinophilic syndrome (HES).Objective: To characterise T-cell expansion in eosinophilic lung disease.Methods: T-cell expression profile was analysed by flow cytometry and TCR clonal gene rearrangements were studied by PCR in 45 consecutive patients with peripheral blood eosinophilia (greater than 1.0×109/L) and eosinophilic lung disease. Patients with myeloid or lymphocytic variants of HES or any identified cause of eosinophilia were excluded.Results: Clonal TCR rearrangements were detected in 11/45 patients (24%): 4/18 with hypereosinophilic asthma, 3/17 with Churg-Strauss syndrome, 3/9 with idiopathic chronic eosinophilic pneumonia (ICEP), and 1/1 with allergic bronchopulmonary aspergillosis. Seven patients had 2 clonal rearrangements or more. TCR rearrangements involved the TCRγ chain in 10 patients and the TCRδ chain in one patient with ICEP. Aberrant T-cell immunophenotype usually found in HES (CD3-CD4+, CD3+CD4-CD8-, or CD3+CD7)-, and known to produce IL-5, was not detected. No significant clinical or biological difference was found between patients with or without clonal TCR gene rearrangements. IL-5 serum level was normal in all patients.Conclusion: Expansion of TCR-Vγ or TCR-Vδ populations are present in a proportion of patients with eosinophilic lung disease without aberrant cell-surface immunophenotype. Further study is needed to evaluate whether T-cell clonality might contribute to the pathophysiology of these conditions or is only a transient reactive phenomenon.