An in vitro study on MS patient's peripheral blood mononuclear cells (PBMCs), conducted in 2016, showed increased activity of TH1 and Th17 subsets on the production of IL-17 and IFN-γ in relapsing patients and a decrease in IL-17 production after the addition of 5-HT [19]. The gene discussed is IFNG; the disease is myeloid sarcoma.