Publications (2)14.95 Total impact
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Article: IL-10 controls dendritic cell-induced T-cell reactivation in the skin to limit contact hypersensitivity.
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ABSTRACT: IL-10 is a pleiotropic cytokine and potent negative regulator of both innate and adaptive immune responses. Consequently, IL-10-deficient (IL-10(-/-)) mice have enhanced contact hypersensitivity (CHS) to topical hapten. Although the importance of IL-10 production by (regulatory) T cells and Langerhans cells in regulating CHS has been established by cell type-specific il-10 gene targeting, it remains elusive to what extent IL-10 controls dendritic cell (DC) function in vivo. To this aim, we generated mice with a DC-specific deletion of the IL-10 receptor (IL-10R). Despite the ability of IL-10 to inhibit DC maturation in vitro, DCs of resting DC-IL10R(-/-) mice retained their immature phenotype in vivo. In contrast, IL-10R(-/-) DCs produced increased levels of proinflammatory cytokines and IL-10 after in vitro stimulation. Induction of CHS was indistinguishable from that seen in control mice at 24 hours after hapten challenge but resulted in increased ear swelling at 48 hours and delayed resolution of the inflammatory reaction. Adoptive T-cell transfer experiments revealed that only T-cell reactivation and not sensitization by IL-10R(-/-) DCs leads to enhanced CHS. Accordingly, the expression of proinflammatory cytokines and IL-10 was augmented in the skin of DC-IL10R(-/-) mice after hapten challenge. Our data demonstrate that IL-10 signaling in DCs is dispensable during naive T-cell priming but is critical to prevent an exaggerated effector T-cell response in the skin.The Journal of allergy and clinical immunology 01/2012; 129(1):143-50.e1-10. · 9.17 Impact Factor -
Article: TGF-beta is required to maintain the pool of immature Langerhans cells in the epidermis.
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ABSTRACT: The pivotal role of TGF-beta in Langerhans cell (LC) development has been previously established in TGF-beta-deficient mice, which lack epidermal LCs. As to whether TGF-beta also governs LC homeostasis and function remains elusive. To assess the role of TGF-beta-mediated control of cutaneous dendritic cells (DCs) in vivo, we generated mice with a conditional knockout of the TGF-beta receptor 1 (TbetaR1) under a DC-specific promoter (DC-TbetaR1(del) mice). While initial LC seeding occurred in DC-TbetaR1(del) mice, the cells disappeared from the epidermis during the first week of life. TbetaR1-deficient LCs demonstrated spontaneous maturation and gained migratory potential based on increased surface expression of MHC class II, costimulatory molecules, and CCR7 and downregulation of E-cadherin. In parallel to their early loss from the epidermis, migrating LCs were reduced in the dermis and skin-draining lymph nodes of adult DC-TbetaR1(del) mice, whereas the number of Langerin(+) dermal DCs was similar to wild-type. In the absence of LCs, low-dose contact hypersensitivity in DC-TbetaR1(del) mice was significantly diminished. In contrast, ear swelling was restored to wild-type levels when a higher hapten dose was applied to efficiently target TbetaR1-deficient dermal DCs. In conclusion, TGF-beta inhibits in vivo LC maturation and migratory phenotype, identifying TGF-beta as a critical factor controlling LC homeostasis in the steady state.The Journal of Immunology 09/2010; 185(6):3248-55. · 5.79 Impact Factor
