• Efficacy of treatment without calcineurin inhibitors, compared to current standard immunosuppressive treatment [ Time Frame: Throughout study ] [ Designated as safety issue: No ]
  
• Adverse effects of treatment without calcineurin inhibitors, compared to current standard immunosuppressive treatment, especially hypertension, serious infections and chronic nephrotoxicity [ Time Frame: Throughout study ] [ Designated as safety issue: No ]
  

• Immune inhibition detected by sensitive and specific assays (including intragraft and peripheral monitoring) for expression patterns of activation and effector function markers [ Time Frame: Throughout study ] [ Designated as safety issue: No ]
  

Renal transplantation is widely recognized as the treatment of choice for children with end-stage renal disease (ESRD). Although outcomes of renal transplantation in children have improved during the past decade, success has been limited by both non-specific tolerance and the complications associated with immunosuppressants. Steroids and calcineurin inhibitors have the most toxic side effects. Use of sirolimus for immunosuppression has not been associated with as many complications. Recent studies from Europe have demonstrated that sirolimus can be combined with MMF and steroids to provide excellent graft survival in the absence of calcineurin inhibitors. Steroid side-effects can be lessened by tapering the steroid dose to an every-other-day schedule. This protocol tests whether immunosuppression by IL-2r antibody, sirolimus, MMF, and alternate-day steroids will provide comparable graft survival for living donor recipients, compared to current immunosuppression, but with reduced complications of calcineurin inhibitors.

Evaluations prior to transplantation include a complete history and physical examination, CBC, liver function tests, and antibodies for CMV, EBV, HIV, HbsAG, and HCV. All appropriate vaccinations are provided before transplantation. Transplant recipients receive immunosuppression therapy using antibody induction (daclizumab), corticosteroids, mycophenolate mofetil, and sirolimus. Serum sirolimus levels are measured so that doses can be adjusted to maintain certain blood levels of the drug. Bactrim and ganciclovir are given for infection prophylaxis. If the patient has consistent high levels of fasting cholesterol, treatment with lipitor may be given. A transplant biopsy is performed at the time of the transplant and at 3, 6, and 12 months post transplantation and at times when a rejection is suspected. A radionuclide GFR is done at the same time points, and at 1, 24, and 36 months. The protocol biopsies, blood, and urine samples will be analyzed by genomic methods to determine differences in gene expression post transplantation. In the event of a first acute rejection, patients are treated with Solu-Medrol for 3 consecutive days. A second rejection (at the discretion of the transplant center) or severe rejection (Banff Grade 3) is treated with antibody therapy and, after a second or severe rejection, the immunosuppressant regimen is changed. Patients are followed for 36 months with routine physical examinations and laboratory assessments.