Because HPV(+) and HPV(−) exosomes derived from plasma of patients who typed as HPV(+) or HPV(−) based on p16 analyses were equally efficient in their ability to mediate immune suppression or apoptosis in activated human effector T cells, we concluded that tumor-derived exosomes carrying an excess of inhibitory ligands and paucity of co-stimulatory proteins are likely to be immunosuppressive, as also previously reported (29). This evidence concerns the gene CDKN2A and neoplasm.