Fractalkine, a CX3C chemokine, is expressed by dendritic cells and is up-regulated upon dendritic cell maturation.
The lone CX3C chemokine, fractalkine (FK), is expressed in a membrane-bound form on activated endothelial cells and mediates attachment and firm adhesion of T cells, monocytes and NK cells. We now show that FK is associated with dendritic cells (DC) in epidermis and lymphoid organs. In normal human skin, dual-color fluorescence microscopy co-localized FK expression with Langerhans cells expressing CD1a. In tonsil, FK-positive DC expressed CD83, a marker for mature DC. Human and murine cultured DC up-regulated FK mRNA expression with maturation. Furthermore, CD40 ligation, but not TNF-alpha or lipopolysaccharide treatment, of activated, migratory DC that had migrated from skin explants resulted in a 2.5-fold increase of surface expression of FK without significant alterations of expression of CD80, CD86, CD54 or MHC class II. Since FK mediates adhesion of T cells to activated endothelial cells, the increased expression of FK during DC maturation (and particularly by CD40 ligation) may play a role in the ability of T cells and mature DC to form conjugates and engage in cell-cell communication.
Papadopoulos
E J
EJ
Dermatology Branch, National Cancer Institute, Bethesda, USA.
Sassetti
C
C
Saeki
H
H
Yamada
N
N
Kawamura
T
T
Fitzhugh
D J
DJ
Saraf
M A
MA
Schall
T
T
Blauvelt
A
A
Rosen
S D
SD
Hwang
S T
ST
D000818:Animals; D001483:Base Sequence; D023201:CD40 Ligand; D002448:Cell Adhesion / Q000276:immunology; D002450:Cell Communication / Q000276:immunology; D002454:Cell Differentiation / Q000276:immunology; D002460:Cell Line; D054428:Chemokine CX3CL1; D020523:Chemokines, CX3C; D019743:Chemokines, CXC / Q000235:genetics* / Q000378:metabolism*; D017931:DNA Primers / Q000235:genetics; D003713:Dendritic Cells / Q000166:cytology / Q000276:immunology*; D006801:Humans; D007801:Langerhans Cells / Q000276:immunology; D008544:Melanocytes / Q000276:immunology; D008562:Membrane Glycoproteins / Q000494:pharmacology; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D014066:Palatine Tonsil / Q000166:cytology / Q000276:immunology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012867:Skin / Q000166:cytology / Q000276:immunology; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D015854:Up-Regulation
C515538:CX3CL1 protein, human; D054428:Chemokine CX3CL1; D020523:Chemokines, CX3C; D019743:Chemokines, CXC; C515539:Cx3cl1 protein, mouse; D017931:DNA Primers; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D023201:CD40 Ligand