OLIG1 and ischemic stroke: Although Tbx18-tdT+ cells can generate a small number of Sox2+ i-NSCs following ischemic stroke at both 1 and 3 dpi (Figure 5B-C, and Figure S9A-B), they barely produce DCX+ neuroblasts and Olig1+ OL lineage cells (Figure 5D-G and Figure S9D-E).