Might interest some and perhaps be worth keeping an eye out for new studies.
In any case, this process is probably all messed up in us.
Small Intestine:
Researchers identify unexpected player in intestinal immunity: (slightly older 2012)
news.wustl.edu/news/Pages/23546.aspxHere is the full study: Goblet cells deliver luminal antigen to CD103+ DCs in the small intestine
www.ncbi.nlm.nih.gov/pmc/articles/PMC3313460/Newer findings (2014) in the colon:
Microbial sensing by goblet cells controls immune surveillance of luminal antigens in the colon:
www.nature.com/mi/journal/vaop/ncurrent/full/mi201458a.html