Hypoxia directly enhances dendritic cell antigen presentation

Abstract

Event Abstract Back to Event Hypoxia directly enhances dendritic cell antigen presentation Sistiana Aiello1*, Federica Rocchetta1, Nadia Azzollini1, Paola Cassis1, Samantha Solini1, Marilena Mister1, Giuseppe Remuzzi1 and Marina Noris1 1 IRCCS Istituto di Ricerche Farmacologiche Mario Negri, Italy Danger molecules from ischemic tissues activate innate immunity by increasing dendritic cell (DC) immunogenicity. To evaluate whether hypoxia directly impacts on DC antigen presentation capacity, we used mouse B6-OVA-DCs, expressing chicken OVA peptides in the context of class I and II MHC, and OVA-specific TCR-transgenic B6 syngeneic CD8 (OTI) and CD4 (OTII) T cells. Bone-marrow derived OVA-DCs were pre-exposed for 4hr to 1% (hypoxia) or 20% O2 (normoxia) and then used as stimulators of OTI or OTII T cells for 2 days. Higher numbers of IFNγ-producing CD8 and CD4 T cell clones emerged (p<0.05) in response to hypoxic than to normoxic OVA-DCs (OTI 162±26, OTII 72±20 vs: OTI 115±23, OTII 36±15 spots/50000 cells, n=4). A larger increase of IFNγ-producing clones was found in response to hypoxic OVA-DCs exposed to conditioned medium (cm) from hypoxic OVA-B6 renal tubuli vs normoxic OVA-DC exposed to cm from normoxic tubuli (p<0.01). Similarly, non-transgenic B6-DCs pre-incubated with OVA protein (plus hypoxic tubular cm) during hypoxia, induced higher numbers of IFNγ-producing T cell clones than normoxic B6 DCs (pre-incubated with OVA plus normoxic tubular cm): OTI 60±15, OTII 50±10 vs OTI 31±8, OTII 23±6 spots, n=3, p<0.05. This indicates that hypoxia augmented the capacity of DCs to present and cross-present antigens to CD4 and CD8 T cells, respectively. Altogether these results suggest that hypoxia increases antigen presentation by DCs both by direct action on DCs and through release of soluble factors from injured tissues. Such events eventually translate into an augmented adaptive T cells immune response. Keywords: Ischemia, Dendritic Cells, Ovalbumin, OTI mice, OTII mice Conference: 15th International Congress of Immunology (ICI), Milan, Italy, 22 Aug - 27 Aug, 2013. Presentation Type: Abstract Topic: Adaptive Immunity Citation: Aiello S, Rocchetta F, Azzollini N, Cassis P, Solini S, Mister M, Remuzzi G and Noris M (2013). Hypoxia directly enhances dendritic cell antigen presentation. Front. Immunol. Conference Abstract: 15th International Congress of Immunology (ICI). doi: 10.3389/conf.fimmu.2013.02.00620 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: 13 Jun 2013; Published Online: 22 Aug 2013. * Correspondence: Dr. Sistiana Aiello, IRCCS Istituto di Ricerche Farmacologiche Mario Negri, Bergamo, Italy, sistiana.aiello@marionegri.it 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 Sistiana Aiello Federica Rocchetta Nadia Azzollini Paola Cassis Samantha Solini Marilena Mister Giuseppe Remuzzi Marina Noris Google Sistiana Aiello Federica Rocchetta Nadia Azzollini Paola Cassis Samantha Solini Marilena Mister Giuseppe Remuzzi Marina Noris Google Scholar Sistiana Aiello Federica Rocchetta Nadia Azzollini Paola Cassis Samantha Solini Marilena Mister Giuseppe Remuzzi Marina Noris PubMed Sistiana Aiello Federica Rocchetta Nadia Azzollini Paola Cassis Samantha Solini Marilena Mister Giuseppe Remuzzi Marina Noris 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.