To study this in T1D, the in vitro-derived SC-β cells were acutely subjected to several chemical stressors and the persistence of SC-β cells was evaluated through assessment of the co-expression of β-cell markers C-peptide+/NKX6-1+ (Fig. 3b and Supplementary Fig. 6). Here, NKX6-1 is linked to type 1 diabetes mellitus.