(a) The combination of IL-1β, IL-6, VCAM1, IP-10, Cathepsin S, and TGFβ2 (Combo) enhanced NeuroD1 promoter activity in NSPCs, analyzed by luciferase activity assays (p<0.01, n=14); (b) Immunofluorescent images showing TuJI+ neurons (red) differentiated from NSPCs that were treated by IL-1β, IL-6, Combo and RA in the absence of FGF-2. Such fluorescent staining results were quantified using unbiased stereology quantification to generate data shown in Fig 4c and Fig 5d. (c) A Z-stack confocal image of a TuJI+ neurons differentiated from IL-6 treated NSPCs; (d) IL-1β, IL-6 and Combo could promote neuronal differentiation of NSPCs indicated by the percentage of TuJI+ neurons. Combo was significantly more potent than IL-1β and IL-6 alone. *, p<0.05; **, p<0.01, ***, p<0.001 (unpaired, 2-tailed, student's t-test).