The crucial role of dendritic cells in rhinitisKleinJan, AlexCurrent Opinion in Allergy and Clinical Immunology: February 2011 - Volume 11 - Issue 1 - p 12–17 doi: 10.1097/ACI.0b013e328342335f Rhinitis, sinusitis and upper airway disease: Edited by Ruby Pawankar and David P. Skoner Abstract Author Information Purpose of review Dendritic cells generally play an important role as sentinels in the immune system. They are also very important in protecting the airways from invading pathogens and harmful particles and antigens. This review discusses current knowledge about dendritic cell function and the interaction between dendritic cells and their surroundings, the epithelium, during their presence in the nasal mucosa. Recent findings There are some phenotypical differences between myeloid dendritic cells and plasmacytoid dendritic cells in different types of rhinitis. Since it has become possible to perform functional studies on purified dendritic cell populations obtained from the upper airway mucosa, a number of studies have appeared. Some confirm that thymic stromal lymphopoietin is present in the nasal mucosa and that it may influence dendritic cell–T-cell interaction in a pro-Th2 way. Epithelial cells share several characteristics with dendritic cells, but they cannot migrate and move antigens to draining lymph nodes. Summary Several functional dendritic cell studies have been published indicating that there are disease-dependent dendritic cell differences in rhinitis. In addition to these differences, factors like epithelial cells and T cells influence dendritic cells. Several new therapeutic options are available targeting direct or indirect dendritic cell functions. Department of Pulmonary Medicine, Erasmus MC Rotterdam, Rotterdam, The Netherlands Correspondence to Alex KleinJan, PhD, Department of Pulmonary Medicine, Erasmus MC Rotterdam, Dr Molewaterplein 50, 3015 GE Rotterdam, The Netherlands Tel: +31 10 7043701; fax: +31 10 7044728; e-mail: firstname.lastname@example.org Copyright © 2011 Wolters Kluwer Health, Inc. All rights reserved.