Adult renal tubular organoids can be produced from different human individuals in a completely same protocol

IntroductionOrganoids are miniature organs produced by newly emerging technologies. Kidney organoids originated from human inducible pluripotent stem cells (iPSCs) were developed to recapitulate renal diseases. However, producing iPSC kidney organoids from multiple individuals at the same time and in a uniform condition is still impossible. Here, we report adult renal tubular organoids, "tubuloids", established from primary renal epithelial cells from multiple human individuals in a uniform manner. MethodsKidneys obtained from patients due to the surgery for malignancy were minced into small pieces, and primary renal epithelial tubule cells are cultured. 4 patients had normal kidney function and 4 had mild chronic kidney disease (CKD). Growth factors were added to the primary cultured cells at the same time and Matrigel was added to these 8 lines. ResultsPrimary cultured renal epithelial cells from normal kidneys showed a large number of fine, swollen epithelial appearance. On the other hand, primary cultured kidney epithelial cells from mild CKD kidneys were smaller and slightly elongated than those of normal kidneys. The growth speed was faster in normal kidney cells than in mild CKD cells. At the beginning of the three-dimensionalization (day 0), normal renal tubuloids grew faster than mild CKD tubuloids. The difference in size between normal tubuloids and mild CKD ones became less noticeable on day 5. Both types of tubuloids reached almost same size on day 10. All 8 strains are of different human origin, and uniform tubuloids could be produced at the same time and in a uniform protocol. ConclusionIn terms of pathological models, the differences between mouse models and humans cannot be ignored, and there is a great need for a more human-like model of human pathology from both medical and research perspectives. Our renal tubular organoids can be produced in a uniform manner at the same time. It is expected to be used as a new type of convenient human pathological model.