CD28 and Miyoshi myopathy: In CLL, CXCR5+PD‐1+ CD8 T cells show increased differentiation, whereas in DLBCL, MM, and FL, CXCR5+PD‐1+ CD8 T cells remain in a memory‐like state similar to HC, with high expression of CD27, CD28, and CCR7 (Fig. 3D and Supporting Information Fig. S3).