In order to correlate miRNA levels with the eventual inflammatory status of ME/CFS patients, the levels of seven of the most relevant cytokines involved in autoimmune diseases (IFN-γ, IL-17A, IL-2, IL-21, IL-23, IL-6, and TNF-α) were quantified in plasma samples from 39 patients and 20 controls, using the MILLIPLEX MAP Human High Sensitivity T Cell Panel—Immunology Multiplex Assay on Luminex 200 System. Here, IL21 is linked to autoimmune disease.