In a previous study on MS patients [22] we found that the “down- or up-regulation” of sCD30 levels, respectively linked to the “up- or down-regulation” of TGFβ levels, within physiological or pathological ranges, are dual biomarker for homeostasis or imbalance in immunological and neurological pathways and success or failure of IFNβ therapeutic treatment. The gene discussed is IFNB1; the disease is myeloid sarcoma.