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The influence of donor age on function of renal allografts from live related donors.

To assess the influence of donor age on renal allograft outcome, we retrospectively analyzed all 169 consecutive cyclosporine-treated live related donor kidney transplants, of whom 40 were HLA identical siblings. All recipients were similar with respect to demographic and immunologic characteristics. Incidence of rejection episodes and graft survival rates at 1 and 5-year posttransplant were independent of donor age. Best renal function, as assessed by the mean of the lowest 3 serum creatinine concentration levels in the first 2 months posttransplant correlated positively with donor age, particularly among HLA mismatched male recipients (r = 0.4, P < 0.002). Short and intermediate term renal function was inferior, but stable in the older donor recipient group when compared to the younger cohort. Mean serum creatinine levels at 5 years in recipients of kidneys from older donors (age > 55 years) was 2.6 mg/dl compared to 1.7 and 1.9 mg/dl in recipients of kidneys from donors between the ages of 18-39 and 40-54 years, respectively (P < 0.001). In view of the universal shortage of organs and the negligible morbidity to the donors, our results should not discourage the use of kidneys from elderly (age > 55 years) donors.

Adult↗

Short-term immunosuppressive treatment of the donor ameliorates consequences of ischemia/ reperfusion injury and long-term graft function in renal allografts from older donors.

BACKGROUND: Grafts from so-called "marginal donors" are increasingly used for organ transplantation. The combination of reduced organ quality and additional inflammatory damages may be particularly detrimental in these grafts. In a previous study, we showed the beneficial effects on long-term graft outcome of "suboptimal" grafts by the induction of heme oxygenase-1. Here we tested the impact of short-term donor treatment with established immunosuppressants. METHODS: Twelve-month-old Fischer 344 donor rats either were treated with prednisolone, mycophenolate mofetil, RAD, or FK506 24 hr and 1 hr before organ harvesting or remained untreated. Renal allografts were perfused with University of Wisconsin solution and kept at 4 degrees C for an ischemic period of 2 hr. Morphologic, immunohistologic, and real time reverse transcriptase-polymerase chain reaction analyses for relevant markers were performed at serial intervals and at the end of the observation period (6 months). RESULTS: All animals survived the observation period, although the ischemic time resulted in accelerated chronic graft dysfunction. Grafts from donors treated with prednisolone or FK506 demonstrated significantly improved graft function and structure by 6 months. Mononuclear infiltrates were significantly reduced by the end of the observation period, whereas intragraft mRNA levels of tumor necrosis factor-alpha and interleukin-10 were significantly altered during the early period after transplantation. Minor improvements in graft function and histologic alterations of suboptimal grafts were observed after pretreatment with mycophenolate mofetil and RAD. CONCLUSION: Donor treatment with approved immunosuppressants, in particular prednisolone or FK506, represents a novel therapeutic strategy of clinical relevance, most importantly when using grafts from marginal donors.

Age Factors↗

Function of pancreas allografts more than 1 year following transplantation.

At the University of Iowa, Iowa City, 75 pancreas transplant procedures were performed for type I diabetes mellitus from March 1984 to September 1988. Forty-seven of these transplants were performed simultaneously with kidney transplants from the same donor; 23 followed previous kidney transplants, and 5 were preuremic pancreas-only transplants. The 1-year patient survival rate is 85% and pancreas graft survival rate is 54%. The simultaneous kidney and pancrease group had a 1-year patient survival rate of 82%, a pancreas graft survival rate of 59%, and a renal graft survival rate of 73%. Thirty-one of 70 kidney and pancreas recipients had a functioning pancreas 1 year post transplantation and 26 of 31 currently have a functioning pancreas and are insulin free. Patient symptoms of neuropathy and gastroenteropathy are improved with long-term graft function. Some patients may develop type II diabetes post transplantation with impaired glucose tolerance despite high insulin production by the graft. Pancreas transplantation is the only therapy that achieves a euglycemic state as indicated by glycosylated hemoglobin and glucose tolerance testing. Centers must continue to follow up patients on a long-term basis to determine the final effects on the secondary complications of diabetes.

Diabetes Mellitus, Type 1↗

Rapid conversion to sirolimus for chronic progressive deterioration of the renal function in kidney allograft recipients.

The aim of this study was to evaluate the safety of conversion to sirolimus (SRL) immunosuppression among 19 renal transplant recipients (KTX) with progressive chronic renal allograft dysfunction (CRAD). Conversion to SRL was performed with concomitant sharp withdrawal of the calcineurin inhibitor (CI). SRL was added at a starting dose of 3 mg, then adjusted to obtain SRL target trough blood levels of 8 to 10 ng/mL. CI were stopped the evening before starting SRL. All patients enrolled in the study have now completed 6 months of follow-up: all are alive without acute rejection or major infection following rapid conversion to SRL. No significant change in the 6 months postconversion hematologic and hepatic profile was observed compared with the preconversion values, while significant dyslipidemia was induced. After conversion to SRL, significant amelioration of the renal function was found in 36% of patients, stabilization in 21%, and continuous deterioration in 43%. Patients whose renal function improved were found to have been converted at a significantly lower creatinine: (pre 2.6 +/- 0.9 vs post 1.9 +/- 0.2; P =.038) with respect to those patients who had continuous renal deterioration. In KTX with CRAD, sharp withdrawal of CI with concomitant conversion to SRL is safe, avoiding major infections, acute rejections, and significant side effects. Short-term amelioration of the renal function is best obtained when early conversion is performed. Long-term follow-up will be necessary to confirm these preliminary data.

Creatinine↗

Two-color immunofluorescence flow cytometric analysis of lymphocytes in long-term renal allograft recipients.

We used 2-color immunofluorescence flow cytometry (FACS 440) and monoclonal antibodies (Becton-Dickinson) to study peripheral blood lymphocytes subsets from 26 patients with well functioning renal allografts for longer than 5 years. Comparisons were made to a group of 25 healthy volunteers and 25 dialysis patients awaiting renal transplantation. As anticipated, there was no significant difference with respect to the absolute number or percentage of activated (T11+ and HLA-DR+) and cytotoxic (Leu-2+ and Leu-15-)T lymphocytes among the 3 groups. However, there was a significantly decreased absolute number (p equals 0.0001) and percentage (p equals 0.0001) of suppressor cells (Leu-2+ and Leu-15+) in the transplant patients compared to the healthy control group. No significant differences existed between the transplant and dialysis groups. There also was an increase in the percentage (p equals 0.000) but not in the absolute number of T helper lymphocytes (Leu-3+ and Leu-8-) in the transplant population compared to healthy controls. No significant difference existed between the transplant and dialysis groups. These findings suggest that a normal value of cytotoxic (Leu-2+ and Leu-15-) and activated (T11+ and HLA-DR+) T lymphocytes may be a good prognostic indicator of long-term survival of renal allografts. Also, the highly significant decrease in the number of Leu-2+ and Leu-15+ cells in long-term, well functioning allografts indicates that additional functional characterization of this subset may be necessary.

Adult↗

Successful extrarenal transplantation from non-heart-beating donors.

The current organ shortage has made utilization of organs from less-than-ideal donors more common. Although several transplant centers use kidneys from non-heart-beating donors (NHBDs), there has been reluctance to extend the use of these donors to extrarenal organs. Of the 130 donors referred to our organ procurement organization between January 1993 and May 1994, 16 (12.3%) were NHBDs. Organ retrieval from 10 of these resulted in extrarenal donation, 5 resulted in renal donation only, and 1 resulted in no retrieval as a result of prolonged warm ischemia (> 2 hr). A total of 39 organs were transplanted from these NHBDs. A rapid en bloc retrieval technique was used for extrarenal NHBDs. The mean warm ischemic time was 15.4 min; preservation times were similar for both NHBDs and heart-beating donors. After liver transplantation (n = 5), one episode of primary nonfunction that was technical in origin required retransplantation. Following simultaneous pancreas-kidney transplantation (n = 6), all patients were insulin independent and free of graft pancreatitis; one patient required hemodialysis (16.7%). After isolated renal transplantation (n = 21), 3 patients (14.3%) required hemodialysis. Three of 4 liver recipients are alive after a mean follow-up period of 12.7 months; all simultaneous pancreas-kidney and renal transplant recipients are alive after a mean follow-up period of 8.4 and 8.3 months, respectively. Three liver allografts, 5 pancreas and kidney allografts, and 19 renal allografts are functioning. The lung allograft was lost to rejection 81 days after transplantation; however, the recipient is alive 3 months after retransplantation. Our results demonstrate that in controlled situations, extrarenal organs can be utilized from NHBDs and can be expected to function similarly to organs retrieved from heart-beating donors. We increased the number of transplanted organs by 8.6% using NHBDs for both renal and extrarenal donation. Continued application of these techniques will likely further increase the number of organs retrieved for transplantation.

Heart↗

Conversion to sirolimus from cyclosporine may induce nephrotic proteinuria and progressive deterioration of renal function in chronic allograft nephropathy patients.

Antiproliferative and non-nephrotoxic properties of sirolimus have been exploited for treatment of patients with chronic graft dysfunction. In this paper we point to the possible association of nephrotic syndrome and renal impairment with rapid conversion from cyclosporine (CsA) to sirolimus in patients with chronic nephropathy. Five male patients, ages 34 to 56 years, with chronic renal failure in the course of glomerulonephritis, were transplanted between 1997 and 1999. For the first 49 to 65 months, the immunosuppressive regimen consisted of CsA, azathioprine (AZA), and prednisone. Thereafter, due to chronic nephropathy evidenced by biopsy, conversion to sirolimus was performed with sharp withdrawal of CsA. The serum creatinine level prior to conversion was 1.9 +/- 0.3 mg/dL. Trace to 86 mg/dL proteinuria was found in 3 patients, while 2 patients had about 200 mg/dL. After 2 to 4 months of sirolimus treatment the proteinuria progressed (558 +/- 183 mg/dL); edema, hypoproteinemia, hypoalbuminemia, and hyperlipidemia developed; and the serum creatinine increased to 3.5 +/- 0.8 mg/dL. Biopsies performed in three patients revealed new pathologic changes. After 4 to 5 months, we performed reconversion to calcineurin inhibitor. Proteinuria decreased to 0 to 150 mg/dL; nevertheless the serum creatinine was continuously rising. Six to 15 months after the conversion, 3 patients returned to dialysis. The fourth patient, who was earlier reconverted, has a serum creatinine level of 2.0 mg/dL after 15 months. In conclusion, conversion from CsA to sirolimus may induce nephrotic syndrome with progressive deterioration of renal function. Converted patients require careful monitoring of proteinuria and renal function. Early reconversion to calcineurin inhibitor may prevent progressive deterioration of graft function.

Adult↗

Effects of intraventricular substantia nigra allografts as a function of donor age.

Transplantation of fetal substantia nigra into the brain can alleviate some of the manifestations of animal models of Parkinson's disease. The purpose of the present experiment was to determine the optimal embryonic donor age for solid tissue substantia nigra grafts. Rats with unilateral substantia nigra lesions were tested for rotational behavior in response to apomorphine. Animals then received intraventricular grafts of ventral mesencephalon from fetal donors of 11, 13, 15, 17, or 19 days gestational age, and were tested for rotational behavior 6 and 12 weeks after transplantation. After 12 weeks, animals receiving grafts from donors of 11 through 17 days gestation showed similar decreases (means = 42-58%) in rotation. All 4 groups showed greater decreases in rotation than the 19 day group (17%). In both the 11 and 13 day groups, however, there were substantial decreases in rotational behavior from the 6th to the 12th week testing periods. This study confirms that during a critical period of rat fetal development, between 17 and 19 days gestational age, the substantia nigra loses much of its ability to produce functional effects after transplantation. Grafts from very immature donors did not, however, produce markedly greater effects, and the youngest grafts required more time for the development of maximal effects.

Animals↗

Peripheral blood and intrahepatic subsets of T lymphocyte activation and function in liver allograft rejection and drug-induced tolerance in rats.

T lymphocyte kinetics in liver allograft rejection were studied by measuring levels of activated (CD25+ and class II MHC+) T lymphocytes (CD5+) and T cell subsets (CD4 and CD8) in peripheral blood and the livers of allogeneic DA (RT1b) to LEW (RT1') and syngeneic LEW to LEW orthotopic rat liver transplants. Median survival was 10 days in untreated allogeneic rats (n = 17). Mean (+/- SEM) T lymphocyte class II MHC expression increased from 3.4 +/- 0.44% (day 2/3) to 4.9 +/- 1.1% (day 7) (p = 0.01). Complete sequential data were available for nine animals over the period of rejection confirming the increase in class II MHC expression (p = 0.05) and showing a decrease in CD25 expression (p = 0.05). There was a significant fall in CD4:CD8 ratio from day 2/3 to day 7 (p = 0.002). CD25 and class II MHC molecule expression and the CD4:CD8 ratio remained unchanged over the comparable period in the syngeneic LEW to LEW control model (n = 5, p > 0.3 for all comparisons). Cyclosporin A (5 mg/kg/day) was given orally for 17 days and then withdrawn to induce allograft tolerance in a further nine DA to LEW rats (median survival > 100 days). Samples taken at 2/3, 7, 17, 30, 40 and 100 days showed that T cell activation marker expression remained low during cyclosporin treatment (e.g. class II MHC expression 2.32 +/- 0.35%; CD25 expression 3.53 +/- 0.44% on day 7) but increased thereafter (e.g. class II MHC expression 8.19 +/- 0.65%. CD25 13.25 +/- 0.95% on day 100). There was a fall in CD4:CD8 ratio throughout (p < 0.001). Intrahepatic mononuclear cells were harvested from six normal livers, four allogeneic livers (at 10 days), five syngeneic livers (at 10 days) and five tolerant allografts (at 100 days). Rejecting grafts showed the highest proportion of T lymphocytes (66.8 +/- 4.0% vs 18.5 +/- 3.6% in controls, p = 0.01). T cell activation was higher in both rejecting and tolerant grafts versus normal control livers (p = 0.05 for CD25 and p < 0.01 for class II MHC expression). CD8+ lymphocytes predominated in the hepatic infiltrate in all models, although the majority of these cells were both CD5 and alpha beta T cell receptor negative. There was a higher proportion of T cells in tolerant allografts (44.5 +/- 5.2%, p < 0.01) compared with control animals. Serial changes in peripheral T lymphocyte subsets may be useful in monitoring experimental acute rejection. In peripheral blood, the increase in T cell activation and loss of CD4+ lymphocytes, along with evidence of increased intragraft infiltration by this subset implies that it has a primary role in the development of tolerance in this nodel.

Animals↗