title: Regulation of E-cadherin-mediated adhesion in Langerhans cell-like dendritic cells by inflammatory mediators that mobilize Langerhans cells in vivo.
abstract: Adhesion of Langerhans cells (LC) to keratinocytes is mediated by E-cadherin. IL-1, TNF-alpha, and LPS mobilize LC from epidermis and presumably attenuate LC-keratinocyte adhesion. To determine whether these mediators modulated LC E-cadherin-dependent adhesion directly, we characterized their effects on LC-like dendritic cells expanded from murine fetal skin (FSDDC). FSDDC were propagated from day 16 C57BL/6 fetal skin and isolated as aggregates (FSDDC-A) in which homophilic adhesion was mediated by E-cadherin. IL-1, TNF-alpha, and LPS induced dissociation of FSDDC-A that began within 4 to 8 h and was complete within 20 h. Anti-IL-1RI mAb inhibited disaggregation caused by IL-1alpha and IL-1beta, but not that induced by TNF-alpha or LPS. Anti-TNF-alpha mAb inhibited the effect of TNF-alpha and LPS, but not that caused by IL-1alpha or IL-1beta. Flow cytometry of FSDDC-A revealed that IL-1, TNF-alpha, and LPS induced increased expression of MHC class II, CD40, and CD86 and decreased E-cadherin expression that was temporally related to dissociation of aggregates. IL-1 and TNF-alpha caused a rapid reduction in FSDDC E-cadherin mRNA levels that preceded the decrease in E-cadherin surface expression. These results demonstrate that cytokines that induce LC emigration in vivo act directly on LC-like cells in vitro, reduce E-cadherin mRNA levels, down-regulate E-cadherin surface expression, and induce a loss of E-cadherin-mediated adhesion.
authors.affiliation: Dermatology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
authors.forename: T
authors.initials: T
authors.lastname: Jakob
authors.forename: M C
authors.initials: MC
authors.lastname: Udey
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D000954:Antigens, Surface / Q000378:metabolism; D015820:Cadherins / Q000235:genetics / Q000502:physiology*; D002448:Cell Adhesion / Q000187:drug effects / Q000502:physiology; D002449:Cell Aggregation / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D016207:Cytokines / Q000494:pharmacology / Q000502:physiology; D018836:Inflammation Mediators / Q000494:pharmacology* / Q000502:physiology; D007375:Interleukin-1 / Q000494:pharmacology; D007801:Langerhans Cells / Q000166:cytology / Q000187:drug effects* / Q000502:physiology*; D008070:Lipopolysaccharides / Q000494:pharmacology; D051379:Mice; D010641:Phenotype; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
chemical_list: D000911:Antibodies, Monoclonal; D000954:Antigens, Surface; D015820:Cadherins; D016207:Cytokines; D018836:Inflammation Mediators; D007375:Interleukin-1; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha