Supplementary Figure 10: Trajectories and morphologies of P1S5D grafted neurons at 1.5 months after transplantation.

(a) Landmarks of the adult mouse brain are identified by tissue autofluorescence. The image represents 100-μm thick maximum projection of optical sections taken at the center of an adult mouse brain after iDISCO processing, and shows the major myelinated tracts from 488 nm laser excitation via endogenous fluorescence. (b) Examples of axons from grafted neurons following major pathways. iDISCO treated 1.5 months old mouse brain grafted at birth, stained for GFP. In the hippocampus, grafted neurons that are present in CA3 (arrow) and are sending axons along the fimbria tract toward the septum. In the cortex, grafted neuron project fibers across the hemisphere following callosal axons. (c) Examples of axons from grafted neurons not following major pathways. Maximum projections, 100 μm thick, of whole iDISCO treated 1.5 months old mouse brains grafted at birth, stained for GFP. In the striatum, GFP+ axons descending from the grafted neurons in the cortex are seen mainly outside of the main descending tracts. In the cortex, large bundles of GFP+ axons are observed in aberrant position. (d) A few representative morphologies seen in the grafted brains: most human neurons are clustered in the graft core, and therefore their dendritic morphologies are masked. However, a few GFP+ neurons are found outside of the graft core and exhibit diverse morphologies as shown. N = 3. Scale bars: 1 mm (a), 500 μm (b,c), 200 μm (d).