title: Maturation and migration of murine dendritic cells in situ. Observations in a skin organ culture model.
abstract: Dendritic cells reside in tissues such as skin in an immature state. Upon antigenic challenge they begin to mature and migrate to the draining lymph nodes. These processes are still poorly understood. One way to study in situ aspects of maturation and migration are skin organ culture models. In an attempt to learn more about the relationship between maturation and migration we investigated the expression of several marker molecules by immunohistochemistry. Sheets from normal murine ear skin and from skin that had been cultured for three days were compared. During culture the numbers of epidermal Langerhans cells decreased and accumulations of strongly MHC class II-positive cells ("cords") were found in the dermis. As compared to untreated skin, the few Langerhans cells remaining in the epidermal sheets after 2-3 days expressed increased levels of MHC class II and had also upregulated B7-2 (CD86) as described. They did not express the antigen recognized by mAb 2A1, a marker for mature dendritic cells. Double-staining of dermal sheets after 3 days of culture showed that dendritic cells in the "cords" expressed high levels of MHC class II and CD86 but were also reactive with mAb 2A1. This pattern is identical to those dendritic cells that had emigrated into the culture medium over the period of 3 days. Invariant chain (mAb In1) was detected at all stages of culture as opposed to isolated epidermal Langerhans cells in suspension where invariant chain expression disappears after 3 days of culture. We conclude that the up- (class II, B7-2, 2A1) and down-regulation (invariant chain) of dendritic cell molecules during migration does not happen in a synchronized manner. The molecule recognized by mAb 2A1 seems to appear late in maturation.
authors.affiliation: Department of Dermatology, University of Innsbruck, Austria.
authors.forename: H
authors.initials: H
authors.lastname: Stösel
authors.forename: F
authors.initials: F
authors.lastname: Koch
authors.forename: N
authors.initials: N
authors.lastname: Romani
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D015703:Antigens, CD / Q000378:metabolism; D000944:Antigens, Differentiation, B-Lymphocyte / Q000378:metabolism; D051940:B7-2 Antigen; D002454:Cell Differentiation; D002465:Cell Movement; D000949:Histocompatibility Antigens Class II / Q000378:metabolism; D007801:Langerhans Cells / Q000166:cytology* / Q000276:immunology / Q000502:physiology*; D008562:Membrane Glycoproteins / Q000378:metabolism; D051379:Mice; D009924:Organ Culture Techniques; D012867:Skin / Q000166:cytology
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D000944:Antigens, Differentiation, B-Lymphocyte; D051940:B7-2 Antigen; C497965:Cd86 protein, mouse; D000949:Histocompatibility Antigens Class II; D008562:Membrane Glycoproteins; C045084:invariant chain