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employs embryonic spinal cord and Wnt4-expressing 3T3 feeder cells efficiently
differentiates both mouse and human PSC-derived nephron progenitors into neph-
ron structures. These three-dimensional nephron structures include spherical glo-
merular podocytes and proximo-distally specified nephric tubules (Fig. 9.7).
Intriguingly, such conformation changes take place in a similar sequence to those of
the in vivo morphological processes. At day 3 of differentiation, renal vesicle-like
structures were observed. At day 6, S-shaped bodies were specified into E-cadherin+
presumptive distal tubules, cadherin 6+ proximal tubules, and WT1+ glomerular
podocytes. Finally, capillary convolution takes place within the glomerular struc-
ture, later developing into the spherical renal corpuscle at approximately day 9
(Sharmin et al. 2015 ) (Fig. 9.8). Scanning electron microscopy identified the
Bowman’s capsule surrounding the glomerulus and primitive foot process-like and
slit diaphragm-like structures in between the induced podocytes in vitro.
The podocytes are aligned along the type IV collagen-positive basement mem-
brane. Additionally, an apicobasally polarized distribution of cell surface molecules
is present, including apically distributed podocalyxin and basally localized nephrin,
podocin, and neph1 (Fig. 9.9). Microarray gene expression analysis utilizing a
newly generated nephrin-GFP knock-in iPSC identified well-conserved molecular
signatures within mouse adult podocytes and human adult glomeruli. Such mole-
cules include podocyte development-related transcriptional factors and cytokines
D3HEWT1/GFPGFPD6 D6 D9Fig. 9.8 Fluorescent visualization of human glomerular podocytes generated from NPHS1-GFP
iPS cells. Histologic sections of glomeruli developing in vitro. Tissues at days 3, 6, and 9 after
recombination with the spinal cord were analyzed. Top panels: hematoxylin-eosin (HE) staining.
Middle panels: GFP (green) staining. Bottom panels: dual staining with GFP and WT1. Nuclei
were stained with 4′9,6-diamidino-2-phenylindole (DAPI, blue). Scale bars, 20 μm
A. Taguchi and R. Nishinakamura