Nestin-positive MSCs increase astrocytes number in differentiating neural stem cell cultures. Neurosphere-derived GFP-expressing cells were co-cultivated with npMSCs or nnMSCs on polyornithine-coated dishes. After 5 days, the cells were fixed and immunostained with antibodies raised against GFAP (A, D, red), Tuj1 (B, E, red) and O4 (C, F, red). Nuclei were counterstained with EtD1 (blue). Co-cultures with npMSCs are illustrated in A (n = 12, ***Student T-test, P < 0.001), B (n = 12, ***Student T test, P < 0.0001) and C (n = 8, ***Student T test, P < 0.0001). Co-cultures with nnMSCs are illustrated in D (n = 8, Student T test, P > 0.05), E (n = 8, ***Student T test, P < 0.001) and F (n = 8, Student T test, P > 0.05). Stained cells counting results are shown in G and include the control condition of neurosphere-derived cells without co-culture. Scale bars = 20 μm in A-F.