title: Eosinophil-derived leukotriene C4 signals via type 2 cysteinyl leukotriene receptor to promote skin fibrosis in a mouse model of atopic dermatitis.
abstract: Atopic dermatitis (AD) skin lesions exhibit epidermal and dermal thickening, eosinophil infiltration, and increased levels of the cysteinyl leukotriene (cys-LT) leukotriene C(4) (LTC(4)). Epicutaneous sensitization with ovalbumin of WT mice but not ΔdblGATA mice, the latter of which lack eosinophils, caused skin thickening, collagen deposition, and increased mRNA expression of the cys-LT generating enzyme LTC(4) synthase (LTC(4)S). Skin thickening and collagen deposition were significantly reduced in ovalbumin-sensitized skin of LTC(4)S-deficient and type 2 cys-LT receptor (CysLT(2)R)-deficient mice but not type 1 cys-LT receptor (CysLT(1)R)-deficient mice. Adoptive transfer of bone marrow-derived eosinophils from WT but not LTC(4)S-deficient mice restored skin thickening and collagen deposition in epicutaneous-sensitized skin of ΔdblGATA recipients. LTC(4) stimulation caused increased collagen synthesis by human skin fibroblasts, which was blocked by CysLT(2)R antagonism but not CysLT(1)R antagonism. Furthermore, LTC(4) stimulated skin fibroblasts to secrete factors that elicit keratinocyte proliferation. These findings establish a role for eosinophil-derived cys-LTs and the CysLT(2)R in the hyperkeratosis and fibrosis of allergic skin inflammation. Strategies that block eosinophil infiltration, cys-LT production, or the CysLT(2)R might be useful in the treatment of AD.
authors.affiliation: Division of Immunology, Children's Hospital, Boston, MA 02115, USA.
authors.forename: Michiko K
authors.initials: MK
authors.lastname: Oyoshi
authors.forename: Rui
authors.initials: R
authors.lastname: He
authors.forename: Yoshihide
authors.initials: Y
authors.lastname: Kanaoka
authors.forename: Abdallah
authors.initials: A
authors.lastname: ElKhal
authors.forename: Seiji
authors.initials: S
authors.lastname: Kawamoto
authors.forename: Christopher N
authors.initials: CN
authors.lastname: Lewis
authors.forename: K Frank
authors.initials: KF
authors.lastname: Austen
authors.forename: Raif S
authors.initials: RS
authors.lastname: Geha
mesh_terms: D019264:Adoptive Transfer; D000818:Animals; D049109:Cell Proliferation; D003094:Collagen / Q000378:metabolism; D003876:Dermatitis, Atopic / Q000150:complications / Q000276:immunology / Q000473:pathology*; D020405:Dermis / Q000276:immunology / Q000473:pathology; D004195:Disease Models, Animal; D004804:Eosinophils / Q000201:enzymology / Q000378:metabolism*; D005355:Fibrosis; D050980:GATA Transcription Factors / Q000378:metabolism; D005982:Glutathione Transferase / Q000172:deficiency / Q000378:metabolism; D006801:Humans; D007114:Immunization; D015603:Keratinocytes / Q000276:immunology / Q000473:pathology; D017997:Leukotriene C4 / Q000378:metabolism*; D051379:Mice; D010047:Ovalbumin / Q000276:immunology; D018077:Receptors, Leukotriene / Q000378:metabolism*; D015398:Signal Transduction; D012867:Skin / Q000201:enzymology / Q000276:immunology* / Q000473:pathology*
chemical_list: D050980:GATA Transcription Factors; D018077:Receptors, Leukotriene; D017997:Leukotriene C4; D010047:Ovalbumin; D003094:Collagen; C412375:cysteinyl leukotriene receptor 2; D005982:Glutathione Transferase; C041116:leukotriene-C4 synthase; C083169:leukotriene D4 receptor