Proteasomal degradation within endocytic organelles mediates antigen cross-presentation

ABSTRACT: During MHC-I-restricted antigen processing, peptides generated by cytosolic proteasomes are translocated by the Transporter associated with Antigen Processing (TAP) into the endoplasmic reticulum, where they bind to newly synthesized MHC-I molecules. Dendritic cells and other cell types can also generate MHC-I complexes with peptides derived from internalized proteins, a process called cross-presentation. Here we show that active proteasomes within cross-presenting cell phagosomes can generate these peptides. Active proteasomes are detectable within endocytic compartments in mouse bone marrow-derived dendritic cells. In TAP-deficient mouse dendritic cells cross-presentation is enhanced by the introduction of human ?2-microglobulin, which increases surface expression of MHC-I and suggests a

SUBMITTER: Dr. Peter Cresswell 

PROVIDER: S-SCDT-EMBOJ-2018-99266 | biostudies-other |

REPOSITORIES: biostudies-other