Maturational steps of bone marrow-derived dendritic murine epidermal cells. Phenotypic and functional studies on Langerhans cells and Thy-1+ dendritic epidermal cells in the perinatal period.
The adult murine epidermis harbors two separate CD45+ bone marrow (BM)-derived dendritic cell systems, i.e., Ia+, ADPase+, Thy-1-, CD3- Langerhans cells (LC) and Ia-, ADPase-, Thy-1+, CD3+ dendritic epidermal T cells (DETC). To clarify whether the maturation of these cells from their ill-defined precursors is already accomplished before their entry into the epidermis or, alternatively, whether a specific epidermal milieu is required for the expression of their antigenic determinants, we studied the ontogeny of CD45+ epidermal cells (EC). In the fetal life, there exists a considerable number of CD45+, Ia-, ADPase+ dendritic epidermal cells. When cultured, these cells become Ia+ and, in parallel, acquire the potential of stimulating allogeneic T cell proliferation. These results imply that CD45+, Ia-, ADPase+ fetal dendritic epidermal cells are immature LC precursors and suggest that the epidermis plays a decisive role in LC maturation. The day 17 fetal epidermis also contains a small population of CD45+, Thy-1+, ADPase-, CD3- round cells. Over the course of 2 to 3 wk, they are slowly replaced by an ever increasing number of round and, finally, dendritic CD45+, Thy-1+, CD3+ EC. Thus, CD45+, Thy-1+, ADPase-, CD3- fetal EC may either be DETC precursors or, alternatively, may represent a distinctive cell system of unknown maturation potential. According to this latter theory, these cells would be eventually outnumbered by newly immigrating CD45+, Thy-1+, CD3+ T cells--the actual DETC.
Elbe
A
A
Department of Dermatology I, University of Vienna Medical School, Austria.
Tschachler
E
E
Steiner
G
G
Binder
A
A
Wolff
K
K
Stingl
G
G
D000818:Animals; D000954:Antigens, Surface; D001853:Bone Marrow / Q000502:physiology*; D002454:Cell Differentiation; D003713:Dendritic Cells / Q000276:immunology / Q000502:physiology*; D004817:Epidermis / Q000276:immunology / Q000502:physiology*; D005260:Female; D005333:Fetus; D000949:Histocompatibility Antigens Class II / Q000378:metabolism; D007700:Kinetics; D007801:Langerhans Cells / Q000276:immunology / Q000502:physiology*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D010641:Phenotype; D013234:Stem Cells / Q000276:immunology / Q000502:physiology; D018800:Thy-1 Antigens
D000954:Antigens, Surface; D000949:Histocompatibility Antigens Class II; D018800:Thy-1 Antigens