Other “physiologic” tolerogenic factors borrowed by tumor cells include indoleamine 2,3-dioxygenase [IDO; (35)], adenosine production via CD73 expression (36), and secretion of IL-10 (37, 38), transforming growth factor-β [TGF-β; (39)] or soluble CD83 (sCD83). Here, IL10 is linked to neoplasm.