IL4 and myeloid sarcoma: As Th1 cells primarily secrete pro-inflammatory cytokines like IFN-γ, IL-2, and TNF-α whereas Th2 rather secrete anti-inflammatory cytokines such as IL-4, IL-5 and IL-10, exercise can promote a shift from a Th1-mediated pro-inflammatory to a rather anti-inflammatory Th2-mediated cytokine milieu [58,60] which is of particular interest because an imbalance of Th1- and Th2-cells is considered relevant in MS pathogenesis [62].