Next, indirect assessment of exosomal surface levels of immune-checkpoint molecules PD-L1, PD-L2, CTLA-4, TIM-3, and LAG-3 was performed by measuring plasma versus exosome-depleted plasma of HD and HNSCC patients using multiplex bead-based immunoassays. This evidence concerns the gene HAVCR2 and head and neck squamous cell carcinoma.