The cells from which these TCRs were derived (Figure 7C) exhibited very similar gene expression profiles for activation markers and cytotoxic genes in the TILT and Treg-T1D patients, confirming that a similar PRF1+GZMB+CD8+ T cell subset was present in both patient groups but selectively enriched in the ld-IL-2–treated TILT patients. Here, PRF1 is linked to type 1 diabetes mellitus.