Flow cytometry further revealed three prominent features associated with CD161 expression in BM: 1) MM CD8+ T cells and NK cells showed significantly increased CD161 expression versus HC, but no difference in CD4+ T cells (Figure S3C, Supporting Information); 2) among CD8+ T cells, the majority of CD161 expression was restricted to CD69+ TRM, but not CD69‐ Tcir (Figure 3B,C; Figure S3B,C, Supporting Information); 3) compared with HC, the expression of CD161 was significantly upregulated on CD8+ TRM isolated from MM patients (Figure 3C,E,F). Here, CD69 is linked to Miyoshi myopathy.