Purpose of review: The kidney has an elaborate and complicated structure comprising several cell types. Damage or destruction of the kidney thus necessitates reconstruction of all the component cell types to regenerate a functional three-dimensional renal structure. Therefore, despite all the recent advances in our understanding and technical approaches to stem cell and developmental biology, the anatomical complexity of the renal system makes de-novo kidney regeneration the most difficult challenge for organ regenerative therapy.
Recent findings: To build a transplantable neo-kidney, some investigators propose using organogenesis. We suggest the metanephros of the developing kidney and blastocyst complementation can potentially generate a whole kidney with the required three-dimensional structure and renal function to produce urine and erythropoietin. In addition, some researchers are investigating the in-vitro differentiation of pluripotent stem cells into mature renal cells for in-vivo use.
Summary: We review the current challenges to making a transplantable neo-kidney using stem cells.