One study noted 17 cytokines had a significant upward linear trend with the severity of ME/CFS: CCL11 (Eotaxin-1), CXCL1 (GROα), CXCL10 (IP-10), IFN (interferon)-y, interleukin (IL)-4, IL-5, IL-7, IL-12p70, IL-13, IL-17F, leptin, G-CSF, GM-CSF, LIF, NGF, SCF, and TGF-α (231). Here, CXCL1 is linked to myalgic encephalomeyelitis/chronic fatigue syndrome.