Figure 5. Analysis of neuronal grafts.

Confocal analysis of CM-iPSC-derived grafts, 16 weeks post-transplantation. (A) Staining for the microglial marker Iba1 showed the absence of activated microglial cells around the grafts. The insert shows high magnification of microglial cells with a resting phenotype. (B) Staining for the astrocytic marker GFAP revealed the absence of astrogliosis around the grafts. (C) Staining for the proliferation marker Ki-67 showing absence of proliferating cells 16 weeks after transplantation. (D–F) Confocal analysis of iPSC grafts showed that most grafts contained midbrain-like DA neurons. The grafted TH+ cells (red) were colabeled with antibodies against human NCAM (blue) (D–F), FOXA2 (green) (D–E), GIRK2 (blue) (E), Pitx3 (green) (F). (G) Confocal images showing TH+ neurons (red) in a representative graft co-expressing the calcium-binding protein calbindin (red). (H) Confocal images showing the localization of human syntaxin within the graft and in the host striatum. (I) Correlation between number of TH+ neurons and number of rotations (n=9; simple regression, r=0.885, r²=0.784, P=0.01). Scale bar: 100 µm (A–D), 50 µm (A–E), 20 µm (F–I).