(googled this and saw a little about what you are talking about)
If the DC's know (statistically) who to kill with their interferon etc... then maybe they know who to get antigen from? That would increase their efficiency in useful antigen gathering above the purely random across all tissues. (even if they still don't know a neo-antigen from a self antigen)
The cytokine environment tells them, this is a place to fumigate? The cytokine environment also tells them this is a good place to gather antigens?