IL6 and acquired polycythemia vera: Compared to normal controls, PV patients demonstrated significantly higher levels of IL1RA, IL5, IL6, IL7, IL8, IL12, IL13, IFNγ, granulocyte-macrophage colony-stimulating factor (GM-CSF), macrophage inflammatory protein 1α and 1β (MIP-1α and MIP-1β), HGF, IFNγ inducible protein 10 (IP-10), monokine induced by IFNγ (MIG), monocyte chemotactic protein-1 (MCP-1), and VEGF.