All experiments were carried out in accordance with the UBC Animal Care Committee and Canadian Council on Animal Care. Male non-diabetic 8–14 week old NSG mice (005557 NOD.Cg-Prkdc Il2rg/SzJ) were maintained on a 12-h light/dark cycle with ad libitum access to irradiated standard chow diet (#2919) and regular xGVHD monitoring19 . Blood glucose was measured in saphenous vein samples using a OneTouch Verio glucometer (LifeScan) or in intraperitoneal glucose-stimulated insulin secretion tests (ipGSIS), in which mice were fasted for 6 hours then challenged with 2 g/kg glucose. Human C-peptide and engrafted cell phenotype were measured weekly.