Figure 4.

iPSC-derived hNPCs injected into the sensorimotor cortex extend axons along the intrinsic pyramidal tract, projecting to the brain stem. Tissue was stained with anti-human nuclear antigen (anti-HuNu) which detected the cell bolus at the injection site which was either dispersed (white arrows in A) or more compact (white arrows in B). The projections were identified using anti-human neural cell adhesion molecule (anti-hNCAM) and were observed emanating from the bolus through areas of the intrinsic pyramidal tract. These included the internal capsule (C–E), the cerebral peduncles, (F,G) and areas of the pyramids (H,J,J*). To confirm that the fibers observed at 2 weeks post-transplantation within the brain stem were within the pyramidal tract, tissue was stained for protein kinase C gamma (PKCγ), to detect the pyramids (I,J,J*). Abbreviations: ic, internal capsule; cp, cerebral peduncle; py, pyramidal tract. Scale bar in (A,B,F,G) = 250 μm, (C,H) = 200 μm; (D,E,I) = 500 μm; (J,J*) = 150 μm.