Fig. 5: Clinical implication of exosomes derived from the serum of patients with NSCLC.

a Representative images of immunohistochemistry for PD-L1. Scale bars: 50 μm. b Relationship between the number of PD-L1-positive exosomes and PD-L1 expression in tumor tissue. Each dot represents one individual; the horizontal lines represent the medians. c–j Inhibitory effect of exosomes on IL-2 and IFN-γ production in CD8⁺ T cells isolated from 24 patients with NSCLC. CD8⁺ T cells were stimulated with PMA (50 ng mL^–1), ionomycin (500 ng mL^–1), and brefeldin A (3 μg mL^–1) for 4 h after treatment with autologous exosomes from the same patient. Cells were stained with anti-CD8 antibody, fixed, and permeabilized, followed by intracellular staining with anti-human IL-2 and IFN-γ antibodies and analysis using a FACScan flow cytometer. c, d Inhibition of IL-2 and IFN-γ production in individual samples according to treatment with exosomes. e, h Summary of the analysis of IL-2 and IFN-γ production inhibition. Summary of the analysis of IL-2 and IFN-γ inhibition in patients with a high proportion of PD-L1-positive exosomes (f, i) and patients with a low proportion of PD-L1-positive exosomes (g, j). P = 0.0367 by an unpaired two-tailed Student’s t-test (B); P < 0.0001, P = 0.024, P = 0.012, and P = 0.074 by a paired two-tailed Student’s t-test (e–j)