SUMMARY
Despite recent advances in pluripotent stem cell-based approaches inducing the skeletal cells, recapitulating human limb skeletal development in terms of structure and longitudinally oriented growth remains an unresolved challenge. Here, we report a method to differentiate human pluripotent stem cells into region-specific skeletal organoids harboring the interzone/articular chondrocyte progenitors (IZ/ACP) and growth plate chondrocytes (GPC), via PRRX1⁺ limb-bud mesenchymal cells. Comparative analysis demonstrated marked similarities of IZ/ACP and GPC organoid to the human embryonic limb, further characterized with in vivo graft fate and regenerative capacity. We also mimicked the limb skeletal developmental process in a spatially structured manner by vertically positioning two IZ/ACP organoids at both ends of a GPC organoid, namely human skeletal assembloid. Notably, human skeletal assembloid recapitulated an endochondral ossification with a longitudinal skeletal growth upon transplantation. In sum, our study provides a novel research platform for human limb skeletal development and disease.
Competing Interest Statement
The authors have declared no competing interest.
