MS-1 sinusoidal endothelial antigen is expressed by factor XIIIa+, HLA-DR+ dermal perivascular dendritic cells.
We have recently described a monoclonal antibody, termed MS-1, which reacts with sinusoidal endothelium as well as interstitial cells in a variety of nonlymphoid organs. In this report, we characterize the phenotypes of MS-1-positive cells in normal human skin. Double immunohistochemical and immunofluorescence labeling techniques demonstrate that MS-1 antibody identifies two cell types in human dermis: the first represented by weakly reactive lymphatic endothelial cells; and the second comprised of strongly reactive, highly dendritic perivascular cells which constitutively express both HLA-DR and factor XIIIa. These MS-1-positive dendritic interstitial cells are ultrastructurally distinctive, separate from mast cells, phagocytic macrophages, pericytes, blood vascular endothelial cells, and fibroblasts. MS-1-positive cells express this protein in discrete cytoplasmic compartments, and possibly as small plasma membrane-associated regions. The phenotype, dendritic morphology, and perivascular localization of MS-1-positive cells suggest that MS-1 antibody recognizes an epitope expressed by cells previously referred to as dermal perivascular dendritic cells or dermal dendrocytes. We have proposed that MS-1 protein may serve as an anchoring molecule for endothelial cells in sinusoidal spaces in the absence of well-formed basement membranes. MS-1 may similarly function to maintain the spatial relationship of dermal perivascular dendritic cells with the microvasculature.
Department of Dermatology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania.
L J
LJ
Walsh
S
S
Goerdt
J S
JS
Pober
H
H
Sueki
G F
GF
Murphy
D000938:Antigen-Presenting Cells / Q000276:immunology; D000941:Antigens / Q000032:analysis*; D003713:Dendritic Cells / Q000276:immunology* / Q000648:ultrastructure; D004727:Endothelium / Q000276:immunology*; D006684:HLA-DR Antigens / Q000032:analysis*; D006801:Humans; D010641:Phenotype; D012867:Skin / Q000276:immunology* / Q000648:ultrastructure; D011503:Transglutaminases / Q000032:analysis*
D000941:Antigens; D006684:HLA-DR Antigens; D011503:Transglutaminases