FIG. 7.

Model for intracellular events leading to the inhibition of antigen-presentation by intracellular Salmonella. After uptake by BM-DC, Salmonella resides in a membrane-bound compartment that is not permissive for intracellular replication. The SPI2-T3SS is expressed and translocates a set of effector proteins into the cytoplasm of BM-DC. By mechanisms unknown thus far, these effectors interfere with the delivery of processed peptides to compartments that contain MHC-II complexes competent for peptide loading. A putative point of manipulation is the microtubule (MT)-dependent intracellular transport. SPI2 effectors are known to modify MT-dependent transport in other host cells.