Notably, Ptpn2∆IEC mice failed to mount an IL-22 response to Citrobacter infection.52 While in the current study we did not identify which IL-22 producing cells failed to respond in Ptpn2∆IEC-mAIEC mice, based on our prior data with Ptpn2LysMCre mice,52 it is not unreasonable to suggest that the normal presence of PTPN2 in macrophages in Ptpn2∆IEC mice acted as a brake on macrophage IL-22 production in response to infection. This evidence concerns the gene IL22 and infection.