Antigen degradation or presentation by MHC class I molecules via classical and non-classical pathways.
Major histocompatibility complex (MHC) class I molecules usually present endogenous peptides at the cell surface. This is the result of a cascade of events involving various dedicated proteins like the peptide transporter associated with antigen processing (TAP) and the ER chaperone tapasin. However, alternative ways for class I peptide loading exist which may be highly relevant in a process called cross-priming. Both pathways are described here in detail. One major difference between these pathways is that the proteases involved in the generation of peptides are different. How proteases and peptidases influence peptide generation and degradation will be discussed. These processes determine the amount of peptides available for TAP translocation and class I binding and ultimately the immune response.
Division of Tumor Biology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, The Netherlands.
Monique
M
Grommé
Jacques
J
Neefjes
D000071181:ATP Binding Cassette Transporter, Subfamily B, Member 2; D000071450:ATP Binding Cassette Transporter, Subfamily B, Member 3; D018528:ATP-Binding Cassette Transporters / Q000502:physiology; D000818:Animals; D017951:Antigen Presentation; D000941:Antigens / Q000378:metabolism*; D003546:Cysteine Endopeptidases / Q000502:physiology; D003600:Cytosol / Q000378:metabolism; D006056:Golgi Apparatus / Q000378:metabolism; D015395:Histocompatibility Antigens Class I / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D009097:Multienzyme Complexes / Q000502:physiology; D010588:Phagosomes / Q000378:metabolism; D046988:Proteasome Endopeptidase Complex; D013379:Substrate Specificity
D000071181:ATP Binding Cassette Transporter, Subfamily B, Member 2; D000071450:ATP Binding Cassette Transporter, Subfamily B, Member 3; D018528:ATP-Binding Cassette Transporters; D000941:Antigens; D015395:Histocompatibility Antigens Class I; D009097:Multienzyme Complexes; C073119:TAP1 protein, human; C071692:TAP2 protein, human; D003546:Cysteine Endopeptidases; D046988:Proteasome Endopeptidase Complex