The role of the proteasome activator PA28 in MHC class I antigen processing.
The proteasome system is the major source for the generation of viral antigens and tumor antigens presented by major histocompatibility complex class I (MHC class I) molecules. A specific feature of the proteasomal antigen processing machinery is that five of its components are inducible by IFN-gamma. Two of these are the alpha and beta subunits of the proteasome activator PA28. Our results show that PA28 selectively up-regulates the presentation of viral MHC class I epitopes and that down regulation PA28 in tumor cells results in impaired presentation of a human TRP2 tumor antigen.
Institut für Biochemie, Charité-Medizinische Fakültät der, Humboldt Universität zu Berlin, Monbijoustrasse 2, 10117 Berlin, Germany.
Alice
A
Sijts
Yuancheng
Y
Sun
Katarina
K
Janek
Sylvie
S
Kral
Annettte
A
Paschen
Dirk
D
Schadendorf
Peter-M
PM
Kloetzel
D000818:Animals; D017951:Antigen Presentation; D000951:Antigens, Neoplasm / Q000378:metabolism; D018984:Epitopes, T-Lymphocyte; D015395:Histocompatibility Antigens Class I / Q000378:metabolism*; D006801:Humans; D009124:Muscle Proteins; D046988:Proteasome Endopeptidase Complex; D011506:Proteins / Q000502:physiology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology
D000951:Antigens, Neoplasm; D018984:Epitopes, T-Lymphocyte; D015395:Histocompatibility Antigens Class I; D009124:Muscle Proteins; C085047:PSME1 protein, human; D011506:Proteins; C486207:PSME2 protein, human; D046988:Proteasome Endopeptidase Complex