One has to wonder whether destroy is all it does though. Analyzing this as cues about the surroundings seems like it could be pretty useful for successful living, and something evolution could well pick up on. Will we find eventually that some of those nucleic acid fragments were being hauled off for identification in something like an extra inner sense of smell?
No need to wonder if you study the lymphatic system.
Maybe so, but also maybe not quite my point, unless you know something I don't about it.
Sure, some samples will be off to antigen presentation, but does that inform more than this is an encountered foreign substance and this is how to bind to it for neutralization ? Seems like in principle you could take the overview picture have something like olfaction, but for things that hadn't been sufficiently cracked open when it passed the olfactory epithelium. Maybe it's starting to be sorted out, but I'm not up to date on what the neural feedback from the immune system carries.