A novel lysosome-associated membrane glycoprotein, DC-LAMP, induced upon DC maturation, is transiently expressed in MHC class II compartment.
We have identified a novel lysosome-associated membrane glycoprotein localized on chromosome 3q26.3-q27, DC-LAMP, which is homologous to CD68. DC-LAMP mRNA is present only in lymphoid organs and DC. A specific MAb detects the protein exclusively in interdigitating dendritic cells. Expression of DC-LAMP increases progressively during in vitro DC differentiation, but sharply upon activation with LPS, TNFalpha, or CD40L. Confocal microscopy confirmed the lysosomal distribution of the protein. Furthermore, DC-LAMP was found in the MHC class II compartment immediately before the translocation of MHC class II molecules to the cell surface, after which it concentrates into perinuclear lysosomes. This suggests that DC-LAMP might change the lysosome function after the transfer of peptide-MHC class II molecules to the surface of DC.
Schering-Plough Laboratory for Immunological Research, Dardilly, France.
B
B
de Saint-Vis
J
J
Vincent
S
S
Vandenabeele
B
B
Vanbervliet
J J
JJ
Pin
S
S
Aït-Yahia
S
S
Patel
M G
MG
Mattei
J
J
Banchereau
S
S
Zurawski
J
J
Davoust
C
C
Caux
S
S
Lebecque
D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000032:analysis; D015703:Antigens, CD / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D001483:Base Sequence; D002454:Cell Differentiation / Q000502:physiology; D002455:Cell Division / Q000502:physiology; D018076:DNA, Complementary / Q000032:analysis; D003713:Dendritic Cells / Q000166:cytology* / Q000276:immunology / Q000378:metabolism*; D000949:Histocompatibility Antigens Class II / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D008196:Lymph / Q000166:cytology; D051907:Lysosomal Membrane Proteins; D008562:Membrane Glycoproteins / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000096:biosynthesis
D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D018076:DNA, Complementary; D000949:Histocompatibility Antigens Class II; D051907:Lysosomal Membrane Proteins; D008562:Membrane Glycoproteins; D012333:RNA, Messenger