title: Functional CD40 ligand is expressed on epidermal Langerhans cells.
abstract: Epidermal Langerhans cells (LC) are bone-marrow-derived major histocompatibility complex (MHC) class II antigen-expressing antigen-presenting cells (APC) that comprise 1-3% of total epidermal cells (EC). LC express high levels of MHC class II antigen and augment costimulatory molecules such as B7-1, B7-2 during culture. In a previous report, using purified murine LC, we showed that freshly prepared LC (fLC) do not express CD40, whereas cLC express CD40. Tumor necrosis factor alpha (TNF-alpha) enhanced CD40 expression on LC during culture. We examined the expression of CD40L on LC and found that both fLC and cLC expressed mRNA for CD40L. FACS analysis revealed that cLC cultured for 36 h expressed CD40L but fLC did not. When we examined the cytoplasmic CD40L, however, both fLC and cLC expressed cytoplasmic CD40L. TNF-alpha, which up-regulated CD40 expression on LC during culture, did not modulate CD40L. Co-culture of purified LC ith anti-CD40L markedly inhibited the up-regulation of B7-1 expression on LC and caused partial inhibition of B7-2 expression during culture. These results indicate that CD40L is expressed on cLC, and that CD40L on LC modulates the expression of costimulatory molecules such as B7-1 and B7-2 on LC.
authors.affiliation: Department of Dermatology, The University of Tokyo, Japan.
authors.forename: C G
authors.initials: CG
authors.lastname: Salgado
authors.forename: K
authors.initials: K
authors.lastname: Nakamura
authors.forename: M
authors.initials: M
authors.lastname: Sugaya
authors.forename: Y
authors.initials: Y
authors.lastname: Tada
authors.forename: A
authors.initials: A
authors.lastname: Asahina
authors.forename: Y
authors.initials: Y
authors.lastname: Koyama
authors.forename: S
authors.initials: S
authors.lastname: Irie
authors.forename: K
authors.initials: K
authors.lastname: Tamaki
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D015703:Antigens, CD / Q000096:biosynthesis; D051940:B7-2 Antigen; D019013:CD40 Antigens / Q000096:biosynthesis; D023201:CD40 Ligand; D002469:Cell Separation; D002478:Cells, Cultured; D003593:Cytoplasm; D005260:Female; D015870:Gene Expression; D015793:HLA-B7 Antigen / Q000096:biosynthesis; D007801:Langerhans Cells / Q000187:drug effects / Q000276:immunology*; D008562:Membrane Glycoproteins / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology / Q000494:pharmacology
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D051940:B7-2 Antigen; D019013:CD40 Antigens; C497965:Cd86 protein, mouse; D015793:HLA-B7 Antigen; D008562:Membrane Glycoproteins; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D023201:CD40 Ligand