title: Involvement of aquaporin-7 in the cutaneous primary immune response through modulation of antigen uptake and migration in dendritic cells.
abstract: Dendritic cells (DCs) have the ability to present antigen and play a critical role in the induction of the acquired immune response. Skin DCs uptake antigen and subsequently migrate to regional draining lymph nodes (LNs), where they activate naive T cells. Here we show that the water/glycerol channel protein aquaporin 7 (AQP7) is expressed on epidermal and dermal DCs and involved in the initiation of primary immune responses. AQP7-deficient DCs showed a decreased cellular uptake of low-molecular-mass compounds (fluorescein isothiocyanate and Lucifer yellow) and high-molecular-mass substances (ovalbumin and dextran), suggesting that AQP7 is involved in antigen uptake. AQP7-deficient DCs also exhibited reduced chemokine-dependent cell migration in comparison to wild-type DCs. Consistent with these in vitro results, AQP7-deficient mice demonstrated a reduced accumulation of antigen-retaining DCs in the LNs after antigen application to the skin, which could be attributed to decreased antigen uptake and migration. Coincidentally, AQP7-deficient mice had impaired antigen-induced sensitization in a contact hypersensitivity model. These observations suggested that AQP7 in skin DCs is primarily involved in antigen uptake and in the subsequent migration of DCs and is responsible for antigen presentation and the promotion of downstream immune responses.
authors.affiliation: Department of Dermatology, Graduate School of Medicine, Kyoto University, Kyoto, Japan. haramari@kuhp.kyoto-u.ac.jp
authors.forename: Mariko
authors.initials: M
authors.lastname: Hara-Chikuma
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Sugiyama
authors.forename: Kenji
authors.initials: K
authors.lastname: Kabashima
authors.forename: Eisei
authors.initials: E
authors.lastname: Sohara
authors.forename: Shinichi
authors.initials: S
authors.lastname: Uchida
authors.forename: Sei
authors.initials: S
authors.lastname: Sasaki
authors.forename: Shintaro
authors.initials: S
authors.lastname: Inoue
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Miyachi
mesh_terms: D000818:Animals; D000941:Antigens / Q000378:metabolism*; D020346:Aquaporins / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D002465:Cell Movement / Q000276:immunology*; D002478:Cells, Cultured; D002633:Chemotaxis / Q000276:immunology; D003713:Dendritic Cells / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D003877:Dermatitis, Contact / Q000276:immunology; D020405:Dermis / Q000166:cytology / Q000276:immunology*; D004195:Disease Models, Animal; D000078404:Epidermal Cells; D004817:Epidermis / Q000276:immunology*; D005990:Glycerol / Q000378:metabolism; D006241:Haptens / Q000276:immunology; D006967:Hypersensitivity / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D010047:Ovalbumin / Q000276:immunology / Q000494:pharmacology; D010873:Pinocytosis / Q000276:immunology; D014867:Water / Q000378:metabolism
chemical_list: D000941:Antigens; C491927:Aqp7 protein, mouse; D020346:Aquaporins; D006241:Haptens; D014867:Water; D010047:Ovalbumin; D005990:Glycerol