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of the tissue when transplanted regardless of their potential filtration capacity
(Sharmin et al. 2015 ). Although some reports have shown directed or simultaneous
induction of UB lineage cells, they are not programmed enough to exhibit function-
ality (Xia et al. 2013 ; Takasato et al. 2015 ). Therefore, it is desirable to induce fully
competent UB to recapitulate a functional kidney organoid. Furthermore, the
a b c
f
e
*bm
bm
d
en
g
bm
en
Fig. 9.10 Transplanted iPS cell-derived nephron progenitors form vascularized glomeruli. (a)
Hematoxylin-eosin staining showing red blood cells in the induced glomeruli. (b) Hematoxylin-
eosin staining showing the eosin-positive precipitates in the Bowman’s space. (c) Staining of neph-
rin (magenta) and CD31 (green). Right panel shows the basal localization of nephrin. Scale bars:
A, C–F, I, 100 μm; B, 1 μm; G, H, J, 10 μm. (d) Induced podocytes surrounding the vascular
endothelial cells and extending multiple cell processes, shown by transmission electron micro-
copy. (e and f) Formation of slit diaphragm-like structures (arrows) between the cell processes of
induced podocytes. Note the electron-dense substance in the Bowman’s capsule (asterisk). (g)
Fenestrated endothelial cells with diaphragms (black arrowheads). bm, Basement membrane
derived from induced podocytes; en, endothelial cells. Scale bars: A, 1 μm; B, E, 0.5 μm; C, D, F,
0.2 μm
A. Taguchi and R. Nishinakamura