title: Skin langerin+ dendritic cells transport intradermally injected anti-DEC-205 antibodies but are not essential for subsequent cytotoxic CD8+ T cell responses.
abstract: Incorporation of Ags by dendritic cells (DCs) increases when Ags are targeted to endocytic receptors by mAbs. We have previously demonstrated in the mouse that mAbs against C-type lectins administered intradermally are taken up by epidermal Langerhans cells (LCs), dermal Langerin(neg) DCs, and dermal Langerin(+) DCs in situ. However, the relative contribution of these skin DC subsets to the induction of immune responses after Ag targeting has not been addressed in vivo. We show in this study that murine epidermal LCs and dermal DCs transport intradermally injected mAbs against the lectin receptor DEC-205/CD205 in vivo. Skin DCs targeted in situ with mAbs migrated through lymphatic vessels in steady state and inflammation. In the skin-draining lymph nodes, targeting mAbs were found in resident CD8α(+) DCs and in migrating skin DCs. More than 70% of targeted DCs expressed Langerin, including dermal Langerin(+) DCs and LCs. Numbers of targeted skin DCs in the nodes increased 2-3-fold when skin was topically inflamed by the TLR7 agonist imiquimod. Complete removal of the site where OVA-coupled anti-DEC-205 had been injected decreased endogenous cytotoxic responses against OVA peptide-loaded target cells by 40-50%. Surprisingly, selective ablation of all Langerin(+) skin DCs in Langerin-DTR knock-in mice did not affect such responses independently of the adjuvant chosen. Thus, in cutaneous immunization strategies where Ag is targeted to DCs, Langerin(+) skin DCs play a major role in transport of anti-DEC-205 mAb, although Langerin(neg) dermal DCs and CD8α(+) DCs are sufficient to subsequent CD8(+) T cell responses.
authors.affiliation: Department of Dermatology and Venereology, Innsbruck Medical University, A-6020 Innsbruck, Austria.
authors.forename: Vincent
authors.initials: V
authors.lastname: Flacher
authors.forename: Christoph H
authors.initials: CH
authors.lastname: Tripp
authors.forename: Bernhard
authors.initials: B
authors.lastname: Haid
authors.forename: Adrien
authors.initials: A
authors.lastname: Kissenpfennig
authors.forename: Bernard
authors.initials: B
authors.lastname: Malissen
authors.forename: Patrizia
authors.initials: P
authors.lastname: Stoitzner
authors.forename: Juliana
authors.initials: J
authors.lastname: Idoyaga
authors.forename: Nikolaus
authors.initials: N
authors.lastname: Romani
mesh_terms: D000818:Animals; D000906:Antibodies / Q000008:administration & dosage*; D015703:Antigens, CD / Q000276:immunology*; D000954:Antigens, Surface / Q000096:biosynthesis* / Q000502:physiology; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D055879:Gene Knock-In Techniques; D018836:Inflammation Mediators / Q000378:metabolism / Q000502:physiology*; D007271:Injections, Intradermal; D007801:Langerhans Cells / Q000276:immunology / Q000378:metabolism; D037181:Lectins, C-Type / Q000096:biosynthesis* / Q000276:immunology* / Q000502:physiology; D008198:Lymph Nodes / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D037241:Mannose-Binding Lectins / Q000096:biosynthesis* / Q000502:physiology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D015778:Minor Histocompatibility Antigens; D009924:Organ Culture Techniques; D021381:Protein Transport / Q000235:genetics / Q000276:immunology; D051381:Rats; D011956:Receptors, Cell Surface / Q000276:immunology*; D012867:Skin / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology* / Q000378:metabolism / Q000473:pathology
chemical_list: D000906:Antibodies; D015703:Antigens, CD; D000954:Antigens, Surface; C498497:Cd207 protein, mouse; C093569:DEC-205 receptor; D018836:Inflammation Mediators; D037181:Lectins, C-Type; D037241:Mannose-Binding Lectins; D015778:Minor Histocompatibility Antigens; D011956:Receptors, Cell Surface