Transplantation of renal precursor cells: a new therapeutic approach.

The number of kidney transplantations performed per year is limited due to availability of donor organs. One possible solution to the organ shortage is the use of renal xenografts. However, the transplantation of xenografts is complicated by hyperacute and acute rejection. It has been postulated that the host immune response might be attenuated following the transplantation of renal precursor cells or embryonic kidneys (metanephroi) instead of developed (adult) kidneys. Transplanted metanephroi become chimeric organs in that their blood supply originates, at least in part, from the host. It is possible to transplant a developing metanephros, without the use of immunosuppression, from one rat to another. Transplanted metanephroi grow, develop, become vascularized, and function in host rats. Transplantation of metanephroi may be a promising novel therapeutic approach for the treatment of chronic renal failure.