Kidney Transplant in a Bone Marrow Transplant Patient

Interesting transplant case:

A 35 year old man with a history of acute myelogenous leukemia, status post a bone marrow transplant from his sister eight years ago and now cured, who developed chronic kidney disease as a result of prior calcineurin inhibitor toxicity and prior XRT. His CKD has progressed over the past several years and now is at the point where his GFR is <15 and he is starting to lose weight.

He undergoes a living related kidney transplant, from his sister--the same sister who was the bone marrow donor. What is the preferred immunosuppression regimen?

Answer: nothing. The patient's bone marrow is completely repopulated by cells deriving from the patient's sister, and therefore her B & T cells will not recognize the transplanted kidney as foreign. Pretty slick.