Studying The Effect of Novel CAKUT Associated Genes on Kidney Development Using Human Pluripotent Stem Cell Derived Kidney Organoids

Pluripotent Stem Cells are a unique class of cells characterized by their capacity for unlimited self-renewal and ability to differentiate into all three germ layers that comprise the human body. Since their discovery, human pluripotent stem cells (hPSCs) have been increasingly utilized as a tool for the development of cell therapy as well as to model genetic diseases and study embryonic development.

Mutations in DACT1 as well as an additional gene involved in WNT/JNK signaling, were recently discovered during genetic screening of patients suffering from Congenital Anomalies of the Kidney and Urinary Tract (CAKUT). To model the effect of these mutations on embryonic kidney development, we established several lines of hPSCs, in which we targeted each of these genes using the CRISPR/Cas9 system. By directing the differentiation of these mutant hPSCs into kidney organoids, we aimed to create a model that could be used to identify potential pathogenic phenotypes, and thereby to elucidate the molecular mechanisms underlying genetically unsolved cases of CAKUT disease in patients harboring these mutations.

Using this organoid model system, we identified significant phenotypes in mutated cells including impairment of nephron tubule formation as well as differences in structural morphology, limited nephrogenesis, and rapid deterioration of established structures. The results of this work provide a strong foundation supporting both the use of genetically modified hPSC derived kidney organoids to model congenital kidney disease as well as the novel association of these genes with CAKUT in humans.