title: The human thymic dendritic cell phenotype and its modification in culture.
abstract: In order to extend our study of human thymic dendritic cells (DC) we have purified DC by density gradient separation followed by treatment with CD1 and CD2 mAb and antibody-coated immunobeads. The resulting population contains 60 to 75% brightly HLA-DR+ cells. Morphological and functional studies demonstrate that these cells share the common characteristics of dendritic cells. Extensive phenotypic analysis of the purified DC has been made using a panel of mAb. Cytofluorometric assays with mAb reactive with common leucocyte antigen confirm that the brightly HLA-DR+ cells are of mesenchymal origin. Thymic DC express HLA-DQ and HLA-class I antigens. They are also positive for the expression of CD45RA molecules and some express the ICAM-1 and the LFA-1 molecules. DC do not stain with a wide variety of anti-T, -B, and -monocyte or -M phi mAb and lack Fc gamma RIII, CR2, and CR3. Freshly isolated DC failed to stain with OKT6 mAb; however, they progressively acquire the CD1 molecule after a few days culture. The acquisition of CD1 molecule is selective since CD4, CD2, and HLA-ABC molecules are not upregulated under the same conditions. From phenotypic results, it was therefore possible to sort brightly HLA-DR+ or -DQ+ cells and so obtain greater than 90 to 95% purified human thymic DC. Such homogeneous DC populations are obviously of great interest for the study of thymic DC functions.
authors.affiliation: Département de microbiologie et immunologie, Université de Montréal, Québec, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Lafontaine
authors.forename: D
authors.initials: D
authors.lastname: Landry
authors.forename: S
authors.initials: S
authors.lastname: Montplaisir
mesh_terms: D015703:Antigens, CD / Q000032:analysis*; D018949:Antigens, CD1; D015815:Cell Adhesion Molecules / Q000032:analysis; D002469:Cell Separation / Q000379:methods; D002478:Cells, Cultured; D002675:Child, Preschool; D003713:Dendritic Cells / Q000276:immunology*; D005434:Flow Cytometry / Q000379:methods; D006684:HLA-DR Antigens / Q000032:analysis*; D006649:Histocompatibility Antigens / Q000032:analysis; D006801:Humans; D016130:Immunophenotyping; D007223:Infant; D018799:Intercellular Adhesion Molecule-1; D017493:Leukocyte Common Antigens; D016169:Lymphocyte Function-Associated Antigen-1 / Q000032:analysis*; D013950:Thymus Gland / Q000276:immunology*
chemical_list: D015703:Antigens, CD; D018949:Antigens, CD1; D015815:Cell Adhesion Molecules; D006684:HLA-DR Antigens; D006649:Histocompatibility Antigens; D016169:Lymphocyte Function-Associated Antigen-1; D018799:Intercellular Adhesion Molecule-1; D017493:Leukocyte Common Antigens