Can right-sided hand-assisted retroperitoneoscopic donor nephrectomy be advocated above standard laparoscopic donor nephrectomy: a randomized pilot study.

Endoscopic techniques have contributed to early recovery and increased quality of life (QOL) of live kidney donors. However, laparoscopic donor nephrectomy (LDN) may have its limitations, and hand-assisted retroperitoneoscopic donor nephrectomy (HARP) has been introduced, mainly as a potentially safer alternative. In a randomized fashion, we explored the feasibility and potential benefits of HARP for right-sided donor nephrectomy in a referral center with longstanding expertise on the standard laparoscopic approach. Forty donors were randomly assigned to either LDN or HARP. Primary outcome was operating time, and secondary outcomes included QOL, complications, pain, morphine requirement, blood loss, warm ischemia time, and hospital stay. Follow-up time was 1 year. Skin-to-skin time did not significantly differ between both groups (162 vs. 158 min, P = 0.98). As compared to LDN, HARP resulted in a shorter warm ischemia time (2.8 vs. 3.9 min, P < 0.001) and increased blood loss (187 vs. 50 ml, P < 0.001). QOL, complication rate, pain, or hospital stay was not significantly different between the groups. Right-sided HARP is feasible but does not confer clear benefits over standard right-sided LDN yet. Further studies should explore the value of HARP in difficult cases such as the obese donor and the value of HARP for transplantation centers starting a live kidney donation program (Dutch Trial Register number: NTR3096). Nevertheless, HARP is a valuable addition to the surgical armamentarium in live donor surgery.

Susceptibility of human mesenchymal stem cells to tacrolimus, mycophenolic acid, and rapamycin.

BACKGROUND: Mesenchymal stem cells (MSC) have multilineage differentiation and immunomodulatory capacities and are potentially useful for therapeutic applications, such as tissue regeneration and control of alloreactivity. MSC are present in most tissues including the transplantable organs. It is therefore unavoidable that MSC will be exposed to immunosuppressive drugs in a clinical transplantation setting. The molecular targets of these drugs are expressed in MSC, but the effect of their inhibition on MSC functioning is unknown. METHODS: MSC were isolated and expanded from heart tissue and the effects of the calcineurin inhibitor tacrolimus, the cell cycle inhibitor mycophenolic acid (MPA), and the mammalian target of rapamycin inhibitor on MSC survival, proliferation, differentiation, and immunosuppressive capacity were examined. RESULTS: Short-term exposure to the immunosuppressants did not induce toxicity or apoptosis in MSC, but high-dose tacrolimus induced toxicity after 7 days. MPA and rapamycin inhibited MSC proliferation at therapeutic doses. The immunosuppressants had differential effects on the differentiation capacity of MSC. Tacrolimus reduced the expression of troponin T type 2 and desmin during cardiomyogenic differentiation of MSC, whereas MPA decreased the deposition of calcified minerals during osteogenic differentiation. Rapamycin stimulated lipid production during adipogenic differentiation. Unexpectedly, MSC had adverse effects on the immunosuppressive efficacy of tacrolimus and rapamycin. There was no such effect of MSC on the function of MPA. Preincubation of MSC with tacrolimus increased the immunosuppressive capacity of MSC. DISCUSSION: This study demonstrates that therapeutic concentrations of immunosuppressive drugs affect MSC function. MSC affect the efficacy of immunosuppressive medication. These findings are important for potential clinical use of MSC in combination with immunosuppressants.

No important influence of limited steroid exposure on bone mass during the first year after renal transplantation: a prospective, randomized, multicenter study.

BACKGROUND: Steroid-related bone loss is a recognized complication after renal transplantation. In a prospective, randomized, multicenter study we compared the influence of a steroid-free immunosuppressive regimen with a regimen with limited steroid exposure on the changes in bone mass after renal transplantation. METHODS: A total of 364 recipients of a renal transplant were randomized to receive either daclizumab (1 mg/kg on days 0 and 10 after transplantation; steroid-free group n=186) or prednisone (0.3 mg/kg per day tapered to 0 mg at week 16 after transplantation; steroids group n=178). All patients received tacrolimus, mycophenolate mofetil, and, during the first 3 days, 100 mg prednisolone intravenously. Changes in bone mineral density (BMD) were evaluated in 135 and 126 patients in the steroid-free and steroids group, respectively. RESULTS: The mean (+/- SD) BMD of the lumbar spine decreased slightly in both groups during the first 3 months after transplantation (steroid-free -1.3 +/- 4.0% [P<0.01]; steroids -2.3 +/-4.2% [P<0.01]). In the following months, lumbar BMD recovered in both groups (P<0.01), resulting in a lumbar BMD at 12 months after transplantation comparable with the baseline value. No difference between the groups was found at 3 months (steroid-free versus steroids +1.0%; 95% confidence interval -0.0%-+2.0%, P=0.060) and at 12 months after transplantation (steroid-free versus steroids +0.9%; 95% confidence interval -0.8%-+2.6%, NS). CONCLUSION: The use of a moderate dose of steroids during 4 months after transplantation has no important influence on bone mass during the first year after renal transplantation. On average, both regimens prevented accelerated bone loss.