CD4 and neoplasm: ACM derived from OGJ patients with early-stage and late-stage tumours increased the expression of PD-L2 on the surface of CD4+ T cells (untrx: 0.65 ± 0.08 vs. early-stage: 2.38 ± 0.6%, p = 0.02, late-stage: 3.69 ± 0.9%, p = 0.01) and CD8+ T cells (untrx: 0.80 ± 0.1 vs. early-stage: 2.73 ± 0.9%, p = 0.03, late-stage: 4.21 ± 1.7%, p = 0.07) compared with untreated cells (Fig. 2B).