Down-regulation of Toll-like receptor expression in monocyte-derived Langerhans cell-like cells: implications of low-responsiveness to bacterial components in the epidermal Langerhans cells.
In the skin, there are unique dendritic cells called Langerhans cells, however, it remains unclear why this particular type of dendritic cell resides in the epidermis. Langerhans cell-like dendritic cells (LCs) can be generated from CD14(+) monocytes in the presence of GM-CSF, IL-4, and TGF-beta1. We compared LCs with monocyte-derived dendritic cells (DCs) generated from CD14(+) monocytes in the presence of GM-CSF and IL-4 and examined the effect of exposure to two distinct bacterial stimuli via Toll-like receptors (TLRs), such as peptidoglycan (PGN) and lipopolysaccharide (LPS) on LCs and DCs. Although stimulation with both ligands induced a marked up-regulation of CD83 expression on DCs, PGN but not LPS elicited up-regulation of expression CD83 on LCs. Consistent with these results, TLR2 and TLR4 were expressed on DCs, whereas only TLR2 was weakly detected on LCs. These findings suggest the actual feature of epidermal Langerhans cells with low-responsiveness to skin commensals.
Takeuchi
Junko
J
Department of Microbiology and Immunology, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, 113-8602, Tokyo, Japan.
Watari
Eiji
E
Shinya
Eiji
E
Norose
Yoshihiko
Y
Matsumoto
Misako
M
Seya
Tsukasa
T
Sugita
Masahiko
M
Kawana
Seiji
S
Takahashi
Hidemi
H
D001419:Bacteria / Q000378:metabolism*; D048429:Cell Size; D002478:Cells, Cultured; D003594:Cytoplasmic Granules / Q000378:metabolism; D015536:Down-Regulation; D000078404:Epidermal Cells; D004817:Epidermis / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D016753:Interleukin-10 / Q000378:metabolism; D018664:Interleukin-12 / Q000378:metabolism; D007801:Langerhans Cells / Q000166:cytology / Q000187:drug effects / Q000276:immunology / Q000378:metabolism*; D018950:Lipopolysaccharide Receptors / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism*; D009000:Monocytes / Q000166:cytology / Q000187:drug effects / Q000276:immunology / Q000378:metabolism*; D010457:Peptidoglycan / Q000494:pharmacology; D010641:Phenotype; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism*; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D051193:Toll-Like Receptors
D018950:Lipopolysaccharide Receptors; D008070:Lipopolysaccharides; D008562:Membrane Glycoproteins; D010457:Peptidoglycan; D011956:Receptors, Cell Surface; C495342:TLR2 protein, human; C495345:TLR4 protein, human; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D051193:Toll-Like Receptors; D016753:Interleukin-10; D018664:Interleukin-12