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Kidney spheroids generate a functional quiescent niche leading to enhanced tubulogenic potency of human kidney-derived cells

ABSTRACT: Cell-based approaches utilizing autologous human renal cells require their isolation, expansion in vitro and reintroduction back into the host for renal tissue regeneration. Nevertheless, human kidney epithelial cells (hKEpC) lose their phenotype, dedifferentiate and assume the appearance of fibroblasts after relatively few passages in culture. We hypothesized that growth conditions may influence hKEpC phenotype and function. hKEpC retrieved from human nephrectomy tissue samples showed the ability to reproducibly form kidney-spheres when grown in suspension culture developed in non-adherent conditions. Genetic labeling and time-lapse microscopy indicated, at least in part, the aggregation of hKEpC into 3D-spheroids rather than formation of pure clonally expanded spheres. Characterization of hKEpC spheroids by real-time PCR and FACS analysis showed up-regulation of some renal developmental and 'stemness' markers compared to monolayer and mostly an EpCAM+CD24+CD133+CD44+ spheroid cell phenotype. Oligonucleotide microarrays which were used to identify global transcriptional changes accompanying spheroid formation, showed predominantly up-regulation of cell matrix/cell contact molecules and cellular biogenesis processes and down-regulation of cell cycle, growth and locomotion. Accordingly, hKEpC spheroids proliferated slowly as indicated by low Ki-67 staining, but when grafted in low cell numbers onto the chorioallantoic membrane (CAM) of the chick embryo, they exclusively reconstituted various renal tubular epithelia. Moreover, efficient generation of kidney spheroids was observed after long-term monolayer culture resulting in re-establishment of tubulogenic capacity upon CAM grafting. Thus, generation of a specialized quiescent niche in hKEpC spheroids may provide a functional benefit for kidney-derived cells in vivo.

ORGANISM(S): Homo sapiens

PROVIDER: GSE28052 | GEO | 2011/12/31

SECONDARY ACCESSION(S): PRJNA139767

REPOSITORIES: GEO

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Kidney spheroids generate a functional quiescent niche leading to enhanced tubulogenic potency of human kidney-derived cells

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