IL4 and ischemia: In the current study, we have studied the effects of soluble factors derived from differently activated human macrophages (M1(IFN-γ), M2a(IL-4), and M2(LS)) on proliferation, differentiation, and survival of SH-SY5Y cells under serum deprivation (an in vitro ischemia model) and a combination of deprivation and CoCl2-induced hypoxia (an in vitro ischemia/hypoxia model).