Reprogramming in vivo th17 into th17/th2 by Sirp-α dendritic cells in the lungs

Quang Van et al. Allergy, Asthma & Clinical Immunology 2011, 7(Suppl 2):A27 http://www.aacijournal.com/content/7/S2/A27 ALLERGY, ASTHMA & CLINICAL IMMUNOLOGY MEETING ABSTRACT Open Access Reprogramming in vivo th17 into th17/th2 by Sirp-a dendritic cells in the lungs Vu Quang Van*, Marianne Raymond, Keiko Wakahara, Manuel Rubio, Marika Sarfati From Canadian Society of Allergy and Clinical Immunology Annual Scientific Meeting 2011 Quebec, Canada. 20-23 October 2011 Background Dendritic cells (DCs) play a crucial role in the development of the adaptive immune response. Unbalance DC response can cause Th1, Th17 or Th2-mediated diseases. By in vitro manipulation, Th2 and Th17 cell lines can be reprogrammed into Th1. This highlights the notion of the plasticity of different populations of CD4 T helper cells. So far, the conversion of Th17 memory cells into Th2 cells has not been demonstrated in the tissues. Methods Mice were immunized by repetitive administration of inflammatory DCs loaded with OVA protein antigen (OVA-DC), locally (intra-tracheal) or systematically (intravenous). Mice were sacrificed 24h after the last challenge and lymph nodes, serum, lungs and bronchoalveolar lavage were collected to evaluate the immune response. Results We showed here, that administration of OVA-DCs generated antigen-specific CD4 T cells that produced IL-17, IL-13 and IL-4 (Th17/Th2) and expressed GATA-3 in the lungs and the lymph nodes. The immunized mice developed an IgE-independent lung inflammation that displayed resistance to treatment with corticosteroids. This inflammation was characterized by a mixed infiltration of neutrophils and eosinophils in the bronchoalveolar lavage. We demonstrated that airway inflammatory SIRP-a DCs converted in vitro-generated Th17 but not Th2 cell lines into Th17/Th2. Finally, passive transfer of Th17/Th2 cells was sufficient to drive airway inflammation in naïve mice. Conclusion We propose that immunization with inflammatory DCs, regardless of the route of immunization, induces chronic inflammation of the airways, which is associated with a Th2/Th17 response. Published: 14 November 2011 doi:10.1186/1710-1492-7-S2-A27 Cite this article as: Quang Van et al.: Reprogramming in vivo th17 into th17/th2 by Sirp-a dendritic cells in the lungs. Allergy, Asthma & Clinical Immunology 2011 7(Suppl 2):A27. Submit your next manuscript to BioMed Central and take full advantage of: • Convenient online submission • Thorough peer review • No space constraints or color figure charges • Immediate publication on acceptance • Inclusion in PubMed, CAS, Scopus and Google Scholar • Research which is freely available for redistribution Immunoregulation Laboratory, Centre Hospitalier de l’Université de Montréal, Research Center CRCHUM, Notre-Dame Hospital, Montréal, Québec, H2L 4M1, Canada Submit your manuscript at www.biomedcentral.com/submit © 2011 Quang Van et al; licensee BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.  (...truncated)