Inhaled and systemic glucocorticoids reduce regulatory T cells numbers in a HDM-model of allergy

Abstract

Event Abstract Back to Event Inhaled and systemic glucocorticoids reduce regulatory T cells numbers in a HDM-model of allergy Jamil Z. Kitoko1, 2*, Tatiana Paula T. Ferreira3, Carolina T. De Azevedo3, Ana Carolina S. De Arantes3, Marco A. Martins3 and Priscilla C. Olsen2, 3 1 Federal University of Rio de Janeiro, Carlos Chagas Filho Institute of Biophysics, Brazil 2 Federal University of Rio de Janeiro, School of Pharmacy, Brazil 3 Oswaldo Cruz Foundation/IOC, Brazil Introduction: Glucocorticoids (GCs) are the main anti-inflammatory compounds used to treat asthma. Several studies suggest that GCs may act by increasing the number and activity of regulatory T (Treg) cells, with subsequent upregulation of IL-10 production. Nevertheless, recent data have shown that GCs can negatively impact the levels of these anti-inflammatory cells. The aim of this study was to clarify the effect of treatment with GCs on Treg cells in experimental asthma. Methods and Results: AJ mice were intranasally challenged with house dust mite (HDM) extract 3 times a week, for 3 weeks. Treatments were performed during the last week of challenge with either nebulized budesonide (bude) or oral dexamethasone (dexa). Analyses were performed 24 h after the last challenge. Broncoalveolar lavage fluid (BALF) analyses showed that dexa reduced leukocyte infiltration (11.07 x105 ± 2.33, n=7), including eosinophil infiltration (4.53 x105 ± 1.55, n=7), both generated by HDM exposure (respectively, 23.71 ± 5.38 and 13.75 ± 3.66 (x105), n=7). Flow cytometry analyses reveals elevated numbers of CD4+CD25+Foxp3+ cells in BALF of mice challenged with HDM (6527 ± 1047, n=6), which were decreased by dexa or bude treatment (respectively, 1817 ± 424.1 and 2824 ± 486.1, n=6). Dexa or bude reduced cellularity (respectively, 3500 ± 471.4 and 9150 ± 1553 (x103), n=9) as well as values of CD4+CD25+Foxp3+ cells (respectively, 67060 ± 6851 and 88670 ± 8568, n=6) in thymus, compared to control groups. By ELISA, elevated numbers of IL-10 were detected in lung of HDM-group mice (432.7 ± 15.4, n=10), while dexa or bude treatment did not altered these values (respectively, 388.3 ± 30.52, n=9 and 451.1 ± 19.76, n=10). All group data are presented as mean ± SEM. License of FIOCRUZ’s Ethics Committee on Use of Laboratory Animals approval is LW-23/10. Conclusion: These data suggest that treatment with GCs reduces lung number of Treg cells in asthma, independently of the route of administration, probably by reducing thymic production of T cells. Acknowledgements CNPq, FAPERJ Keywords: Asthma, Glucocorticoids, Treg cells, Thymus Gland, HDM allergens Conference: IMMUNOCOLOMBIA2015 - 11th Congress of the Latin American Association of Immunology - 10o. Congreso de la Asociación Colombiana de Alergia, Asma e Inmunología, Medellin, Colombia, 13 Oct - 16 Oct, 2015. Presentation Type: Poster Presentation Topic: Immunotherapy Citation: Kitoko JZ, Ferreira TT, De Azevedo CT, De Arantes AS, Martins MA and Olsen PC (2015). Inhaled and systemic glucocorticoids reduce regulatory T cells numbers in a HDM-model of allergy. Front. Immunol. Conference Abstract: IMMUNOCOLOMBIA2015 - 11th Congress of the Latin American Association of Immunology - 10o. Congreso de la Asociación Colombiana de Alergia, Asma e Inmunología. doi: 10.3389/conf.fimmu.2015.05.00274 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 15 Apr 2015; Published Online: 14 Sep 2015. * Correspondence: Mr. Jamil Z Kitoko, Federal University of Rio de Janeiro, Carlos Chagas Filho Institute of Biophysics, Rio de Janeiro, Brazil, jamilkitoko@gmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Jamil Z Kitoko Tatiana Paula T Ferreira Carolina T De Azevedo Ana Carolina S De Arantes Marco A Martins Priscilla C Olsen Google Jamil Z Kitoko Tatiana Paula T Ferreira Carolina T De Azevedo Ana Carolina S De Arantes Marco A Martins Priscilla C Olsen Google Scholar Jamil Z Kitoko Tatiana Paula T Ferreira Carolina T De Azevedo Ana Carolina S De Arantes Marco A Martins Priscilla C Olsen PubMed Jamil Z Kitoko Tatiana Paula T Ferreira Carolina T De Azevedo Ana Carolina S De Arantes Marco A Martins Priscilla C Olsen Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.