Generation and characterization of human cryptorchid-specific induced pluripotent stem cells from urine

Cryptorchidism is a common congenital birth defect in human beings with the possible complication of infertility. An in vitro model of cryptorchidism might be valuable due to the inaccessibility of human embryos for research purposes. In this study, we reprogrammed urine cells containing genetic variations in insulin-like factor 3, zinc finger (ZNF) 214, and ZNF215 from a cryptorchid patient by introducing human OCT4, SOX2, C-MYC, and KLF4 with lentivirus. The cells were then replated on irradiated mouse embryonic fibroblasts and cultured with the human embryonic stem (ES) cell medium. The compact colonies with well-defined borders were manually picked, and 2 induced pluripotent cell lines were fully characterized. Our results demonstrated that these 2 cell lines were similar to human ES cells in morphological appearance, marker expression, and epigenetic status of the pluripotent cell-specific gene, OCT4. These cells could be differentiated into cells of all 3 germ layers in teratomas and in vitro, including into the VASA-positive germ cell lineage. Both parental urine cells and the reprogrammed cells possessed the normal karyotype and the same short tandem repeat loci, indicating that these 2 cell population share the same genetic identity. This establishment and characterization of human urine-derived cryptorchid-specific induced pluripotent stem cells could present a good human genetic system for future studies investigating the molecular mechanism of cryptorchidism.