Notably, Trem2, Cx3cr1, and Ccr5 were highly expressed in M1, M2, M3, and M5 subpopulations (Fig. 3c, e, g) and showed significantly higher expression in the T1D group compared to the Ctrl group, suggesting these genes may play critical roles in T1D pathology (Trem2: p < 0.001; Cx3cr1: p < 0.05; Ccr5: p < 0.001, Fig. 3d, f, h). Here, TREM2 is linked to type 1 diabetes mellitus.