AGR2 and inflammatory bowel disease: While AGR2 expression is higher in patients with IBD in response to increased ER stress and damage, loss-of-function AGR2 genetic variants have also been associated with both CD and UC for their failure to restrain ER stress.21 A recent report of a non-functional AGR2 missense mutation in siblings with infantile IBD revealed AGR2 upregulation and increased ER stress.22 Therefore, to test whether AGR2 promotes or inhibits Enterobacteriaceae dysbiosis, we analyzed the microbiome of littermate, co-housed Agr2−/− and Agr2+/+ mice by 16S rRNA sequencing of ileal contents.