Effect of co-culturing of MNC on ratio of neuronal apoptosis and preservation of neuronal networks. Apoptosis was induced by 48 hours incubation of neuronal cells under hypoxic conditions. Afterwards 4.5 × 105 CFSE stained MNC were directly applied to neuronal cells (0.3 × 105/well). For three days co-cultures were observed under normoxia. In co-cultures with MNC rate of apoptosis was clearly reduced compared to post-hypoxic cultures (A). Combined phase contrast and fluorescence micrograph of post-hypoxic neuronal cells and MNC (green) in direct co-culture (B).