title: Langerhans Cells Suppress CD49a+ NK Cell-Mediated Skin Inflammation.
abstract: Recruitment of innate immune effector cells into sites of infection is a critical component of resistance to pathogen infection. Using a model of intradermal footpad injection of Candida albicans, we observed that inflammation as measured by footpad thickness and neutrophil recruitment occurred independent of adoptive immunity but was significantly reduced in MyD88(-/-) and IL-6(-/-) mice. Unexpectedly, huLangerin-DTA mice (ΔLC) that lack Langerhans cells (LC) developed increased skin inflammation and expressed higher amounts of IL-6, suggesting a suppressive role for LC. Increased inflammation also occurred in Rag1(-/-) ΔLC mice but was reversed by Ab-mediated ablation of NK cells. CXCR6(+)CD49a(+) NK cells are a liver-resident subset that can mediate inflammatory skin responses. We found that exaggerated skin inflammation was absent in ΔLC × CXCR6(-/-) mice. Moreover, the exaggerated response in ΔLC mice could be adoptively transferred with liver CD49a(+) NK cells. Finally, CD49a(+) NK cells in ΔLC but not control mice were recruited to the skin, and inhibition of their recruitment prevented the exaggerated response. Thus, in the absence of LC, CD49a(+) liver NK cells display an inappropriately proinflammatory phenotype that results in increased local skin inflammation. These data reveal a novel function for LC in the regulation of this recently described subset of skin tropic NK cells.
authors.affiliation: Department of Dermatology, Center for Immunology, University of Minnesota, Minneapolis, MN 55455;
authors.forename: Felix
authors.initials: F
authors.lastname: Scholz
authors.affiliation: Laboratory of Mammalian Cell Biology and Development, The Rockefeller University, New York, NY 10065;
authors.forename: Shruti
authors.initials: S
authors.lastname: Naik
authors.affiliation: Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, IA 52242; and Veterans Affairs Medical Center, Iowa City, IA 52241.
authors.forename: Fayyaz S
authors.initials: FS
authors.lastname: Sutterwala
authors.affiliation: Department of Dermatology, Center for Immunology, University of Minnesota, Minneapolis, MN 55455; dankaplan@umn.edu.
authors.forename: Daniel H
authors.initials: DH
authors.lastname: Kaplan
mesh_terms: D019264:Adoptive Transfer; D000818:Animals; D002176:Candida albicans / Q000276:immunology / Q000502:physiology; D002177:Candidiasis / Q000235:genetics / Q000276:immunology / Q000382:microbiology; D002478:Cells, Cultured; D003872:Dermatitis / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D004487:Edema / Q000235:genetics / Q000276:immunology / Q000382:microbiology; D005260:Female; D005434:Flow Cytometry; D005528:Foot / Q000382:microbiology / Q000473:pathology; D039423:Integrin alpha1 / Q000276:immunology* / Q000378:metabolism; D015850:Interleukin-6 / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D007694:Killer Cells, Natural / Q000276:immunology* / Q000378:metabolism / Q000637:transplantation; D007801:Langerhans Cells / Q000276:immunology* / Q000378:metabolism; D008099:Liver / Q000276:immunology / Q000378:metabolism; D008297:Male; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D020556:Neutrophil Infiltration / Q000235:genetics / Q000276:immunology; D054387:Receptors, CXCR / Q000276:immunology / Q000378:metabolism; D000075744:Receptors, CXCR6; D012867:Skin / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D013154:Spleen / Q000276:immunology / Q000378:metabolism
chemical_list: C482906:Cxcr6 protein, mouse; D039423:Integrin alpha1; D015850:Interleukin-6; D054387:Receptors, CXCR; D000075744:Receptors, CXCR6