In theory they're only giving these "desensitization" shots to people who already have been diagnosed with celiac disease. But the idea of sensitization is real: among mothers with celiac disease, their babies are more likely to also have celiac disease the earlier they had wheat products introduced into their diet as babies. But even the diagnosis isn't everything. Among patients with chronic GI symptoms who were all definitively
negative for celiac disease, the ones who kept ingesting gluten had a death rate 4 times higher than those who decided to eliminate gluten despite being negative for celiac.
Why yes, I did write a final research paper this semester on gluten intolerance, why do you ask?
Another fun tidbit: in a study of over 1400 patients diagnosed with schizophrenia who had
no gastrointestinal symptoms at all, 23% of them blood-tested positive for celiac antibodies, and their "schizophrenic" symptoms improved dramatically when they were taken off gluten.