• Patient and graft survival [ Time Frame: At 1 year post-transplant ] [ Designated as safety issue: Yes ]
  

• Patient and graft survival [ Time Frame: At 3 years post-transplant ] [ Designated as safety issue: Yes ]
  
• Incidence rate of biopsy-proven acute rejection, defined as a renal biopsy demonstrating acute cellular or humoral rejection of Banff Grade IA or greater [ Time Frame: 3 years ] [ Designated as safety issue: No ]
  
• Incidence of chronic allograft nephropathy, determined using renal biopsies and laboratory values, including 24-hour urine protein excretion [ Time Frame: 3 years ] [ Designated as safety issue: No ]
  
• Incidence of graft-versus-host disease (GVHD) [ Time Frame: 3 years ] [ Designated as safety issue: Yes ]
  
• Incidence of adverse events associated with renal transplantation and immunosuppression [ Time Frame: 3 years ] [ Designated as safety issue: Yes ]
  

Organ transplantation is a common procedure in hospitals, but organ rejection and serious side effects are potential problems for the patient. Mycophenolate mofetil, sirolimus, and tacrolimus are drugs used to decrease immune system activity in people who have received organ transplants so that the new organ will not be rejected. Alemtuzumab is a monoclonal antibody that binds to and depletes excess T cells in the bone marrow of leukemia patients. In this study, alemtuzumab will be used to destroy the recipient's white blood cells (WBCs) at the time of transplantation. It is hoped that WBCs produced after alemtuzumab administration will recognize the transplanted liver as "self" and will not attack the new kidney.

To further assist the immune system in accepting the donor kidney, some patients in this study will also receive two infusions of bone marrow stem cells from the kidney donor. Bone marrow stem cells are adult blood cells from which other specialized blood cells, such as T cells, develop. Treatment with these cells is believed to create a state of "chimerism" in the body, where the immune cells of both the donor and recipient can coexist and tolerate the presence of a donor organ. This study will evaluate the safety and effectiveness of an antirejection regimen including alemtuzumab and other immunosuppressive medications and donor bone marrow stem cell infusions in patients undergoing kidney transplantation.

This study will last 3 years. Participants will be randomly assigned to receive either the full immunosuppressive therapy and donor bone marrow stem cell infusions (Group 1) or immunosuppressive therapy alone (Group 2). Patients will undergo kidney transplantation at the start of the study on Day 0. Patients will receive inpatient infusions of alemtuzumab on Days 0 and 4. Starting on Day 0, patients will begin taking mycophenolate mofetil; starting on Day 1, patients will also begin taking tacrolimus. On Day 5, patients in Group 1 will receive their first of 2 infusions of purified stem cells taken from the kidney donor's bone marrow; their second infusion of stem cells will occur sometime between Months 4 and 6 post-transplant.

Beginning between Months 4 and 6 post-transplant, all participants will begin receiving low-dose maintenance immunosuppressive therapy with sirolimus, as is typical for post-transplant antirejection therapy. One year post-transplant, patients will be evaluated for the potential to withdraw some or all of this maintenance immunotherapy. Participants will be monitored for 3 years post-transplant. Urine collection will occur at Week 1 and Months 1, 3, 6, and 9. At Months 12, 24, and 30, participants will undergo kidney biopsies. Blood collection will occur at regular intervals for laboratory tests to evaluate the immune system's response to the transplanted kidney.