IL4 and myeloid sarcoma: MS was also associated with alterations in the immune system e.g. elevated levels of blood pro-inflammatory cytokines TNF-α and IFN-γ of MS rats exposed to subsequent open field stress in adulthood [5], increased activity of colonic myeloperoidase [11], [13] and increased colonic mRNA expression of cytokines IFN-γ, IL-1β, IL-2, IL-4, and IL-10 [13].