State Subsets and Correlates with the Maturation Cells Is Restricted to the Nonplasmacytoid Prion Protein Expression by Mouse De
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Prion Protein Expression by Mouse Dendritic Cells Is Restricted to the Nonplasmacytoid Subsets and Correlates with the Maturation State This information is current as of September 30, 2021. Gloria Martínez del Hoyo, María López-Bravo, Patraporn Metharom, Carlos Ardavín and Pierre Aucouturier J Immunol 2006; 177:6137-6142; ; doi: 10.4049/jimmunol.177.9.6137 http://www.jimmunol.org/content/177/9/6137 Downloaded from References This article cites 43 articles, 18 of which you can access for free at: http://www.jimmunol.org/content/177/9/6137.full#ref-list-1 http://www.jimmunol.org/ Why The JI? Submit online. • Rapid Reviews! 30 days* from submission to initial decision • No Triage! Every submission reviewed by practicing scientists • Fast Publication! 4 weeks from acceptance to publication by guest on September 30, 2021 *average Subscription Information about subscribing to The Journal of Immunology is online at: http://jimmunol.org/subscription Permissions Submit copyright permission requests at: http://www.aai.org/About/Publications/JI/copyright.html Email Alerts Receive free email-alerts when new articles cite this article. Sign up at: http://jimmunol.org/alerts The Journal of Immunology is published twice each month by The American Association of Immunologists, Inc., 1451 Rockville Pike, Suite 650, Rockville, MD 20852 Copyright © 2006 by The American Association of Immunologists All rights reserved. Print ISSN: 0022-1767 Online ISSN: 1550-6606. The Journal of Immunology Prion Protein Expression by Mouse Dendritic Cells Is Restricted to the Nonplasmacytoid Subsets and Correlates with the Maturation State1 Gloria Martı´nez del Hoyo,* Marı´a Lo´pez-Bravo,* Patraporn Metharom,2† Carlos Ardavı´n,3,4* and Pierre Aucouturier3,4† Expression of the physiological cellular prion protein (PrPC) is remarkably regulated during differentiation and activation of cells of the immune system. Among these, dendritic cells (DCs) display particularly high levels of membrane PrPC, which increase upon maturation, in parallel with that of molecules involved in Ag presentation to T cells. Freshly isolated mouse Langerhans cells, dermal DCs, and DCs from thymus, spleen, and mesenteric lymph nodes expressed low to intermediate levels of PrPC. Highest levels of both PrPC and MHC class II molecules were displayed by lymph node CD8␣int DCs, which represent fully mature cells having migrated from peripheral tissues. Maturation induced by overnight culture resulted in increased levels of surface PrPC, as did in vivo DC activation by bacterial Downloaded from LPS. Studies on Fms-like tyrosine kinase 3 ligand bone marrow-differentiated B220؊ DCs confirmed that PrPC expression followed that of MHC class II and costimulatory molecules, and correlated with IL-12 production in response to TLR-9 engagement by CpG. However, at variance with conventional DCs, B220؉ plasmacytoid DCs isolated from the spleen, or in vitro differentiated, did not significantly express PrPC, both before and after activation by TLR-9 engagement. PrP knockout mice displayed higher numbers of .spleen CD8␣؉ DCs, but no significant differences in their maturation response to stimulation through TLR-4 and TLR-9 were noticed http://www.jimmunol.org/ Results are discussed in relation to the functional relevance of PrPC expression by DCs in the induction of T cell responses, and to the pathophysiology of prion diseases. The Journal of Immunology, 2006, 177: 6137–6142. he prion protein (PrP)5 was initially described as an es- (PRNP in humans), the structure of which is remarkably conserved sential component of the infectious agents responsible for between species (5). Its physiological product is expressed as a T transmissible spongiform encephalopathies (TSE) (1). GPI-anchored membrane protein termed cellular PrP (PrPC), in TSE are a group of neurodegenerative disorders that include many tissues at variable levels (6, 7). Because neurons generally Creutzfeldt-Jakob disease and kuru in humans, bovine spongiform display strong PrPC expression, and because the CNS is specifi- encephalopathy, sheep scrapie, and chronic wasting disease in deer cally involved during the clinical stages of TSEs, most studies by guest on September 30, 2021 and elk. Although the pathophysiology of TSE remains poorly were devoted to the potential functions of PrPC in the brain (8–11). understood (reviewed in Refs. 2 and 3), an almost invariable fea- Although PrP knockout (PrnpϪ/Ϫ) mice display no gross func- ture is the accumulation of an abnormal isoform of PrP (scrapie Sc tional anomaly, the structure of PrP and its regulated expression PrP, designated PrP ) in infected tissues of affected individuals. during development and cell differentiation suggest that its phys- PrP was found to be encoded by a unique gene of the host (4), Prnp iological role(s) might be more important than one would expect from observations in experimental animals (12). C *Department of Immunology and Oncology, Centro Nacional de Biotecnologı´a/Con- Outside the nervous system, PrP is particularly expressed on sejo Superior de Investigaciones Cientificas, Universidad Auto´noma, Madrid, Spain; the membrane of cells of hemopoietic lineages, including platelets, and †Universite´Pierre et Marie Curie, Unite´Mixte de Recherche S Institut National de la Sante´et de la Recherche Me´dicale Unite´712, Paris, France lymphocytes, and mononuclear phagocytes (7, 13–15). Published C Received for publication May 16, 2006. Accepted for publication August 2, 2006. studies have shown that PrP expression is finely tuned during the The costs of publication of this article were defrayed in part by the payment of page differentiation, maturation, and activation processes of T cells (16, charges. This article must therefore be hereby marked advertisement in accordance 17) and dendritic cells (DC) (18). These observations are of par- with 18 U.S.C. Section 1734 solely to indicate this fact. ticular interest because of the following: 1) lymphoid tissues are 1 This work was supported in part by grants from the Ministerio de Educacio´n y specifically involved in the early stages of TSEs (19, 20); 2) the Ciencia of Spain SAF-2003-07291, Groupement d’Inte´ret Scientifique Maladies a` C Prions, and European Union Contract QLK5-CT-2002-01044. P.M. was a recipient of expression of normal PrP is required for cells to support prion an Institut National de la Sante´et de la Recherche Me´dicale Poste Vert fellowship. replication (21–23); and 3) PrPc might function as a receptor for 2 Current address: Centre for Research in Vascular Biology, BioSciences Institute, scrapie PrP (24). Although sites of prion accumulation during the University College, Cork, Ireland. incubation period are relatively well defined in different TSE mod- 3 C.A. and P.A. contributed equally to this work. els (reviewed in Refs. 19 and 25), the mechanisms responsible for 4 Address correspondence and reprint requests to Dr. Pierre Aucouturier, Universite´ prion penetration and transport remain unclear. Because after ex- Pierre et Marie Curie, Unite´Mixte de Recherche S Institut National de la Sante´etde la Recherche Me´dicale Unite´712, 184 rue du Faubourg Saint-Antoine, 75571, Paris posure to pathogens and/or inflammatory compounds DCs migrate Cedex 12, France; E-mail address: [email protected] or Dr. Carlos Ar- from Ag capture areas to the T cell zones of organized lymphoid davı´n, Department of Immunology and Oncology, Centro Nacional de Biotecnologı´a/ Consejo Superior de Investigaciones Cientificas, Universidad Auto´noma, 28049 Ma- tissues, these cells represent potential candidates as prion carriers. drid, Spain; E-mail address: [email protected] Indeed, DCs were shown to transport prions to the mesenteric 5 Abbreviations used in this paper: PrP, prion protein; DC, dendritic cell; DDC, der- lymph after oral inoculation (26), and to transfer prion infection to mal DC; int, intermediate; LC, Langerhans cell; LN, lymph node; MS-LN, mesenteric LN; pDC, plasmacytoid DC; PrPC, cellular PrP; Flt3L, Fms-like tyrosine kinase 3 the brain (27). Other studies suggest that DCs can degrade TSE ligand; TC, tricolor; TSE, transmissible spongiform encephalopathy. agents (28, 29), as do macrophages (30). Copyright © 2006 by The American Association of Immunologists, Inc. 0022-1767/06/$02.00 6138 PrP EXPRESSION ON DC SUBSETS Thus, although DCs are clearly involved in TSE pathogenesis, carefully titrated to ensure correct quantitative comparisons. After FcR their precise role in the etiology of this disease remains unclear. In blocking with mAb 2.4G2, DCs were analyzed by gating on CD11c-pos- this study, we have specifically analyzed the expression of PrPC by itive cells, after triple staining with FITC-conjugated anti-CD11c (clone N418); PE-conjugated anti-CD8␣ (clone CT-CD8␣); and biotin-conju- DC subpopulations from the skin, thymus, spleen, and lymph gated anti-MHC class II (MHC II; clone FD11-54.3), anti-CD40 (clone nodes (LNs) of the mouse, in an attempt to determine whether FGK45), anti-CD86 (B7-2, clone GL1), or anti-PrP (clone SAF83; pro- distinct DC subsets would be more prone to be differentially tar- vided by J. Grassi, Commissariat a`l’Energie Atomique, Saclay, France), geted by prions. In light of another recent study (31), our results on followed by streptavidin-tricolor (TC; Caltag Laboratories). All analyses, C including before and after overnight culture, were performed in comparison PrP expression by DCs should also help in understanding its with the same cells incubated with the corresponding isotype control Ig. physiological role in the immune system. Analysis of LCs and DDCs was performed by gating on CD11c-positive cells, after double staining with FITC-conjugated anti-CD11c (clone N418) Materials and Methods and biotin-conjugated anti-MHC class II (clone FD11-54.3) or anti-PrP (clone SAF83), followed by streptavidin-PE (Caltag Laboratories). Mice Analysis of plasmacytoid DCs (pDCs) was performed by gating on Five- to 6-wk-old C57BL/6 mice were purchased from IFFA Credo. PrP CD11c-positive cells, after triple staining with FITC-conjugated anti- knockout (PrnpϪ/Ϫ) mice (21) were provided by C.