There are studies, from 1999, about "acquired" gluten intolerance.
They involve the actions of NSAIDs on the intestinal mucosa, and the blocking of Cox-2 cytokines. These cytokines prevent some peptides in food from passing thru the mucosa and entering the circulation. So blocking Cox-2 is not good for the mucosa.

It is possible this genetic flaw, works in tandem with this NSAID triggered event to provide peptides for the immune system to attack. This would explain why some with this flaw develop problems and others not. NSAIDs used to be on RX, and since going OTC are used heavily by people, and recommended by doctors still. After reading the NSAID studies long ago, I could see how acquired gluten sensitivity works, and today it seems to be on the rise especially. Ibuprofen and naproxen are the two most commonly used ones today OTC.