CD4 and precursor B-cell acute lymphoblastic leukemia: In T lymphocytes, VISTA expression was also significantly upregulated, with higher levels observed on CD4+ T cells (29.83% vs. 24.59%, p = 0.045) and CD8+ T cells (22.55% vs. 14.3%, p = 0.005) in B-ALL patients compared to controls (Fig. 2A).