title: Osteopontin deficiency affects imiquimod-induced psoriasis-like murine skin inflammation and lymphocyte distribution in skin, draining lymph nodes and spleen.
abstract: Osteopontin (OPN) that enhances autoimmunity is expressed in psoriasis lesions; however, its functions in psoriatic inflammation are unknown. We investigated the role of OPN in OPN deficient mice (OPN-/-) by inducing psoriasis-like inflammation through skin application of imiquimod (IMQ). OPN-/- mice treated with IMQ showed delayed onset ear swelling and attracted less inflammatory cells to the skin. IMQ-induced lymph node swelling was reduced in the absence of OPN, and IMQ-mediated expansion of B cells was inhibited. Further, reduction of CD4(+) T-cell numbers by IMQ in lymph nodes was suppressed in OPN-/- mice, with an increase in the CD4/CD8 ratio. A comparable pattern was found in spleen. Importantly, IMQ-induced IL-17 and IL-4 expression by CD4(+) lymph node T cells was reduced in OPN-/- mice. In conclusion, OPN may modulate psoriasis-like inflammation through altering lymphocyte distribution in skin and draining lymph nodes and by inducing IL-17 expression of inflammatory T cells.
authors: Department of Dermatology and Allergology, University of Ulm, Ulm, Germany.
authors: Denis F
authors: DF
authors: Frenzel
authors: Lisa
authors: L
authors: Borkner
authors: Jan
authors: J
authors: Scheurmann
authors: Kamayani
authors: K
authors: Singh
authors: Karin
authors: K
authors: Scharffetter-Kochanek
authors: Johannes M
authors: JM
authors: Weiss
mesh_terms: D000634:Aminoquinolines / Q000633:toxicity; D000818:Animals; D004195:Disease Models, Animal; D000077271:Imiquimod; D018655:Lymphocyte Count; D008214:Lymphocytes / Q000187:drug effects / Q000276:immunology / Q000473:pathology; D051379:Mice; D018345:Mice, Knockout; D053495:Osteopontin / Q000172:deficiency* / Q000235:genetics / Q000276:immunology; D011565:Psoriasis / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D012867:Skin / Q000187:drug effects / Q000276:immunology / Q000473:pathology; D013154:Spleen / Q000187:drug effects / Q000276:immunology / Q000473:pathology; D058504:Th17 Cells / Q000187:drug effects / Q000276:immunology
chemical_list: D000634:Aminoquinolines; C506896:Spp1 protein, mouse; D053495:Osteopontin; D000077271:Imiquimod
keywords: Th17; imiquimod; osteopontin; psoriasis