KLRG1 and type 1 diabetes mellitus: Similar to our previous finding in the setting of T1D and immunotherapy (12), TIGIT+KLRG1+ memory CD8+ T cells had increased expression of T cell exhaustion markers including the transcription factor TOX and inhibitory receptors (i.e., LAG-3, CD160, CD244), and reduced expression of cell cycle genes (Figure 2A, Supplementary Table 2).