Cathepsin G is differentially expressed in primary human antigen-presenting cells.
Cathepsins are required for the processing of antigens in order to make them suitable for loading on major histocompatibility complex (MHC) class II molecules, for subsequent presentation to CD4(+) T cells. It was shown that antigen processing in monocyte-derived dendritic cells (DC), a commonly used DC model, is different from that of primary human DC. Here, we report that the two subsets of human myeloid DC (mDC) and plasmacytoid DC (pDC) differ in their cathepsin distribution. The serine protease cathepsin G (CatG) was detected in mDC1, mDC2, pDC, cortical thymic epithelial cells (cTEC) and high levels of CatG were determined in pDC. To address the role of CatG in the processing and presentation of a Multiple Sclerosis-associated autoantigen myelin basic protein (MBP), we used a non-CatG expressing fibroblast cell line and fibroblasts, which were preloaded with purified CatG. We find that preloading fibroblasts with CatG results in a decrease of MBP84-98-specific T cell proliferation, when compared to control cells. Our data suggest a different processing signature in primary human antigen-presenting cells and CatG may be of functional importance.
Stoeckle
Christina
C
Hertie Institute for Clinical Brain Research, University of Tübingen, Germany.
Sommandas
Vinod
V
Adamopoulou
Eleni
E
Belisle
Kurt
K
Schiekofer
Stephan
S
Melms
Arthur
A
Weber
Ekkehard
E
Driessen
Christoph
C
Boehm
Bernhard O
BO
Tolosa
Eva
E
Burster
Timo
T
D017951:Antigen Presentation / Q000276:immunology; D000938:Antigen-Presenting Cells / Q000145:classification / Q000166:cytology / Q000201:enzymology / Q000276:immunology*; D016282:Aspartic Acid Endopeptidases / Q000378:metabolism; D001324:Autoantigens / Q000378:metabolism; D056649:Cathepsin G; D002403:Cathepsins / Q000276:immunology*; D002460:Cell Line; D003546:Cysteine Endopeptidases / Q000378:metabolism; D006801:Humans; D008297:Male; D009103:Multiple Sclerosis / Q000276:immunology; D004676:Myelin Basic Protein / Q000378:metabolism; D012697:Serine Endopeptidases / Q000276:immunology*
D001324:Autoantigens; D004676:Myelin Basic Protein; D002403:Cathepsins; D012697:Serine Endopeptidases; C534094:CTSG protein, human; D056649:Cathepsin G; D003546:Cysteine Endopeptidases; D016282:Aspartic Acid Endopeptidases