PTPN2 and type 1 diabetes mellitus: Second, we have shown that the inducible deletion of PTPN2 in the hematopoietic compartment of adult non‐autoimmune‐prone C57BL/6 mice is sufficient to promote the development of systemic inflammation and autoimmunity (Wiede et al, 2017b), whereas PTPN2 deletion in T cells in autoimmune‐prone NOD1 mice markedly accelerates type 1 diabetes onset, as well as other autoimmune and inflammatory disorders, including colitis (Wiede et al, 2019).