CD8A and B-cell chronic lymphocytic leukemia: PD-1 expression was higher in CD8+ cells from patients with unmutated IGHV genes (U-CLL), a marker of early relapse after fixed-duration therapy (Fig. 5E), and express the lowest p66Shc levels, compared to patients with mutated IGHV genes (M-CLL) (Supplementary Table 3) [20, 27].