TY - JOUR T1 - <em>From the authors:</em> JF - European Respiratory Journal JO - Eur Respir J SP - 285 LP - 286 DO - 10.1183/09031936.00047009 VL - 34 IS - 1 AU - S. Isajevs AU - I. Taivans AU - G. Strazda AU - U. Kopeika AU - M. Bukovskis AU - V. Gordjusina AU - A. Kratovska Y1 - 2009/07/01 UR - http://erj.ersjournals.com/content/34/1/285.abstract N2 - We would like to thank J. Domagala-Kulawik and colleagues for their interesting and useful comments on our previously published article on T-regulatory (Treg) cells in chronic obstructive pulmonary disease (COPD) 1. We took great interest in the findings of the study by Fijalkowski et al. 2, which showed that the proportion of Treg cells (identified by flow cytometry with CD4/CD25/CTLA4 antibodies) was significantly decreased in COPD patients. These results support our conclusions. Upregulation of Treg cells in central airways, as described in our article, corresponds to the the data of Fijalkowski et al. 2 of an increased Treg cell proportion in patients with inflammatory and tumourous lung disease. Inflammation in central airways is present in practically all smokers. Upregulation of Treg cells could be an adaptive reaction of the immune system to increase the peripheral tolerance against self-antigens produced by continuous irritation of airways by tobacco smoke. At the … ER -