A comparative, randomized trial of concentration-controlled sirolimus combined with reduced-dose tacrolimus or standard-dose tacrolimus in renal allograft recipients.

BACKGROUND: The clinical safety and efficacy of sirolimus plus reduced-dose tacrolimus was evaluated in de novo renal allograft recipients enrolled in a comparative, open-label study. METHODS: One hundred twenty-eight renal allograft recipients were randomly assigned (1:1) to receive reduced-dose tacrolimus plus sirolimus (rTAC) or standard-dose tacrolimus and sirolimus (sTAC) for 6 months. The primary efficacy endpoint was calculated creatinine clearance values at 6 months. RESULTS: Demographic variables were similar between groups. At 6 months, mean (± standard deviation) calculated creatinine clearance was significantly improved in the rTAC group (63.8 vs 52.7 mL/min, P = .005), although mean serum creatinine values were not significantly different. Patient survival (95.2% and 96.9%) and graft survival (93.7% and 98.5%) were similar between the rTAC and sTAC groups, respectively. Acute rejection rates were 17.5% with rTAC and 7.7% with sTAC (P = .095). CONCLUSIONS: The rTAC regimen provided effective immunosuppression and was associated with improved creatinine clearance. Adequate immunosuppressant exposure must be achieved in the early postoperative period to minimize the risk of acute rejection.

Renal function in renal or liver transplant recipients after conversion from a calcineurin inhibitor to sirolimus.

Two Six-month pilot studies were conducted in renal (n = 17) or liver (n = 15) transplant recipients to evaluate renal function after conversion from calcineurin inhibitor (CI)- to sirolimus (SRL)-based immunosuppression. After an SRL loading dose, doses were individualized to achieve whole blood trough levels of 10-22 ng/mL. Overall, serum creatinine did not change from baseline to six months post-conversion but an improvement from 219.9 to 201.4 micromol/L at three months was noted in renal transplant recipients (p < 0.05). Another finding was a numerical increase in the mean glomerular filtration rate (GFR) from 26.8 to 33.2 mL/min/1.73 m(2) at six months among liver transplant recipients (NS). All patients survived and all grafts were functioning at the end of the study. In conclusion, renal function remained stable, with a tendency towards improvement, after abrupt conversion from CI- to SRL-based therapy in renal or liver transplant recipients with moderate renal insufficiency.

Bicêtre hospital experience with sirolimus-based therapy in human renal transplantation: the Sirolimus European Renal Transplant Study.

In 11 European centers, first cadaveric renal allograft recipients were randomized to CsA (n = 42) or sirolimus (n = 41). Dosing of these agents was concentration-controlled and open-labeled. All patients received corticosteroids and azathioprine. At 12 months, graft survival (98% sirolimus vs 93% CsA), patient survival (100% vs 98%), and incidence of biopsy-confirmed acute rejection (41% vs 38%) were similar. Serum creatinine was lower with sirolimus, significantly (P

Sirolimus in association with mycophenolate mofetil induction for the prevention of acute graft rejection in renal allograft recipients.

INTRODUCTION: A previous trial in renal transplantation comparing sirolimus (rapamycin) to cyclosporine (CsA) in a triple-drug therapy regimen with azathioprine and corticosteroids found that the incidence of acute rejection was similar (approximately 40%) with a trend for better renal function with sirolimus. METHODS: In 14 European centers, first cadaveric renal allograft recipients were randomized to receive sirolimus (n = 40) or CsA (n = 38) in an open-label design. All patients received corticosteroids and mycophenolate mofetil 2 g/day. Sirolimus and CsA were concentration controlled; trough levels of mycophenolic acid and prednisolone were also measured. RESULTS: At 12 months, graft survival (92.5% sirolimus vs. 89.5% CsA), patient survival (97.5% sirolimus vs. 94.7% CsA), and the incidence of biopsy-proven acute rejection (27.5% sirolimus vs. 18.4% CsA) were not statistically different. The use of antibodies to treat suspected rejection episodes was also similar (7.5% sirolimus vs. 5.3% CsA). More sirolimus patients received bolus steroid therapy (20 vs. 11, P = 0.068). From month 2 onward, the calculated glomerular filtration rate was consistently higher in sirolimus-treated patients. The adverse events reported more frequently with sirolimus were thrombocytopenia (45% vs. 8%) and diarrhea (38% vs. 11%). In the CsA group, increased creatinine (18% vs. 39%), hyperuricemia (3% vs. 18%), cytomegalovirus infection (5% vs. 21%), and tremor (5% vs. 21%) were observed significantly more often. DISCUSSION: Patient and graft survival and the incidence of biopsy-proven acute rejection at 12 months were comparable between sirolimus and CsA, whereas safety profiles were different. These data suggest that sirolimus may be used as primary therapy for the prevention of acute rejection.

[The immune system of the hunter-gatherer meets poverty and excess]. / Jägarens-samlarens immunsystem möter fattigdom och överflöd.

The immune system is closely integrated with the neuroendocrine system, and infection-induced increases in cytokines such as IL-1, IL-6 and TNF have numerous effects on the central nervous system. These include stimulation of the hypothalamus-pituitary-adrenal (HPA) axis, as well as of leptin production. The increase in leptin causes loss of appetite, which may be deleterious for children who are living under conditions of poverty, have frequent infections and are often already undernourished. These cytokines may also be involved in problems of obesity, since they activate the HPA-axis and since TNF is produced by fat cells and can cause insulin resistance. The immune system originally developed for hunter-gatherers may not be well adapted to the pathology of poverty or that of excess.

Sirolimus (rapamycin)-based therapy in human renal transplantation: similar efficacy and different toxicity compared with cyclosporine. Sirolimus European Renal Transplant Study Group.

BACKGROUND: Sirolimus (rapamycin) is a potent immunosuppressant with a mechanism of action different from cyclosporine (CsA) or tacrolimus. METHODS: In 11 European centers, first cadaveric renal allograft recipients were randomized to CsA (n=42) or sirolimus (n=41). Dosing of these agents was concentration-controlled and open-labeled. All patients received corticosteroids and azathioprine. RESULTS: At 12 months, graft survival (98% sirolimus vs. 90% CsA), patient survival (100% vs. 98%), and incidence of biopsy-confirmed acute rejection (41% vs. 38%) were similar. Serum creatinine was lower with sirolimus, significantly (P< or =0.05) so at 3 and 4 months, and serum uric acid and magnesium were normal. Laboratory abnormalities reported significantly more often with sirolimus included hypertriglyceridemia (51% vs. 12%), hypercholesterolemia (44% vs. 14%), thrombocytopenia (37% vs. 0%), leukopenia (39% vs. 14%), and, of lesser importance, increased liver enzymes and hypokalemia. These abnormalities improved 2 months after transplantation when the sirolimus target trough level was lowered from 30 to 15 ng/ml. Occurrence of cytomegalovirus was comparable (14% vs. 12%); incidences of herpes simplex (24% vs. 10%, P=0.08) and pneumonia (17% vs. 2%, P=0.03) were higher with sirolimus. No gingival hyperplasia was seen with sirolimus, tremor was rare, and hypertension was less frequent (17% vs. 33%). Two malignancies were observed with CsA and none with sirolimus. CONCLUSIONS: Results at 12 months suggest that sirolimus can be used as base therapy in the prophylaxis of acute renal transplant rejection, and has a safety profile that differs from CsA.

A randomized multicenter trial of the anti-ICAM-1 monoclonal antibody (enlimomab) for the prevention of acute rejection and delayed onset of graft function in cadaveric renal transplantation: a report of the European Anti-ICAM-1 Renal Transplant Study Group.

BACKGROUND: T-cell activation through T-cell receptor engagement requires co-stimulatory molecules and also adhesion molecules such as ICAM-1. Moreover ICAM-1 mediates leukocyte invasion from the blood into tissue during inflammatory processes. In animal studies using mouse monoclonal antibodies against ICAM-1 (enlimomab), renal allograft survival has been improved and reperfusion damage from ischemia reduced. The European Anti-ICAM-1 Renal Transplant Study (EARTS) was a randomized, double-blind, parallel-group, placebo-controlled study lastingl year and performed in 10 transplant centers in Europe. METHODS: A total of 262 recipients of cadaveric kidneys were given either enlimomab or a placebo for 6 days and were given triple immunosuppressive therapy of cyclosporine, azathioprine, and prednisolone. The primary efficacy endpoint was the incidence of the first acute rejection within 3 months, and each event was assessed by a committee including investigators and independent pathologists. RESULTS: There was no significant difference in the incidences of first acute rejection at 3 months between the placebo and enlimomab groups (39% vs. 45%), and enlimomab did not reduce the risk of delayed onset of graft function (DGF) (26% vs. 31%). Neither was there a difference in patient survival (95% vs. 91%) or graft survival (89% vs. 84%) at 1 year. Fatal events occurred in 19 (7%) patients (7 placebo, 12 enlimomab). Clinically, the most important non-fatal adverse events were infections; however, there was no statistically significant difference between the incidences in the two groups (70% vs. 79%). CONCLUSION: Short term enlimomab induction therapy after renal transplantation did not reduce the rate of acute rejection or DGF.

Alterations of the post transplant blood lymphocyte phenotype subsets as a marker of rejection in renal allograft recipients.

The postoperative alterations of absolute levels of lymphocyte phenotype subsets in peripheral blood were studied in recipients of living donor renal allografts and in kidney donors. The results were expressed as per cent changes of the preoperative values. The lymphocyte subsets, CD3, CD4 and CD8 cells, decreased to approximately 50% following the surgical trauma, with rapid recovery to preoperative levels within 1 week in kidney donors and in recipients without rejection episodes. In contrast, the T-cell levels in recipients with rejection episodes remained low after 1 week, before clinical signs of rejection, and was predictive for the later occurrence of acute rejection episodes. The T-cell levels in the recipients with rejection episodes remained low during the first 6 weeks, maybe due to the rejection treatments given during this period. The B-lymphocytes were not affected in any of the recipient groups. The alterations observed were not explained by CMV infections, which occurred mainly after the observation period of 6 weeks. In conclusion, the operation per se induced alterations in circulating T-lymphocyte subsets and low T-cell levels after 1 week were predictive of rejection episodes.

Physical performance does not improve in elderly patients following successful kidney transplantation.

In a prospective study before, and during 1 year following, kidney transplantation, physical strength and performance were tested in patients over the age of 60 and in younger control patients. Quadriceps strength increased significantly in the control patients (+3.3 +/- 3.2 kg, n = 11, P = 0.007) but remained stable in the successfully grafted elderly patients (-0.1 +/- 4.2 kg, n = 16). Grip strength tended to increase in the control patients (P = 0.064) but not in the elderly. Stepping up on a chair--a test of strength and coordination in combination--could be performed by all control patients on all occasions. Fourteen of 16 elderly patients managed it before transplant, but only 3/12 after 3 weeks, 5/13 after 6 months, and 10/16 after 1 year. Forced expiratory volume during 1 s and working capacity on the ergometer bicycle also tended to decline during 1 year. We conclude that the average elderly person does not gain strength during 1 year after successful kidney transplantation.

Cell-mediated immune responses in renal transplant recipients treated with cyclosporin and prednisolone with or without azathioprine.

The cell-mediated immune response was studied, using mixed lymphocyte reactivity (MLR) and cell-mediated lympholysis (CML) tests, in patients with well-functioning kidney grafts from living donors at 6 and 12 months and at 2-5 years after transplantation. The patients were allocated to treatment with cyclosporin A (CyA) and prednisolone (group A) or with CyA, prednisolone and azathioprine (group B). The MLR towards a third party were in the range of that of untreated controls while the anti-donor activities were reduced after 6 months in both groups. The CML activities in group A towards a third party were in the range of that of untreated controls at all times, while the anti-donor activities were decreased. By contrast, the CML activities in group B towards a third party were decreased during the first year and were in the range of that of normal controls at 2-5 years. The anti-donor CML activities were low at all times in group B. In summary, the two CyA protocols allowed the induction of donor-specific unresponsiveness within the first post-transplant year. The anti-third party activities were low during the first post-transplant year in recipients with triple therapy but not in those without azathioprine.

Alteration in T cell subset phenotypes as cell markers for rejection or long-term allograft acceptance in allografted rats treated with antithymocyte globulin.

The alterations in the absolute levels of lymphocyte phenotype subsets were measured in a rat model for heart allograft acceptance induced by antithymocyte globulin (ATG). In untreated, allografted rats all T lymphocytes decreased with 50% within 3 days after transplantation and recovered within 1 week. ATG alone induced a depletion of 75% of the T lymphocytes, which did not normalise until 60 days after treatment. During the first 10 days, ATG-treated rats with an accepted allograft had higher levels of T lymphocytes than those with rejections while the T lymphocytes recovered faster after day 10 in the later rats. The study demonstrates different alterations in T lymphocytes phenotype subsets between rejecting rats and rats with long-term accepted allograft. It also shows that the operation trauma with rejection as well as the ATG treatment strongly influence the T cell subsets.

Effect of captopril treatment on allograft survival and induction of unresponsiveness in heart-transplanted, ATG-treated rats.

The angiotensin-converting enzyme inhibitor captopril has been suggested to have an immunomodulatory effect both in clinical and experimental studies. To further investigate this possible effect in organ transplantation, captopril was given to inbred rats before transplantation of an allogeneic heart. Captopril was found to prolong graft survival significantly compared to untreated controls. In rats treated with a tolerogenic dose of ATG, additional captopril administration tended to increase the proportion of rats with long-term functioning grafts, but this did not reach statistical significance. It is concluded that captopril displays an immunosuppressive effect that seems to be weak, since no augmentation of ATG-induced transplantation unresponsiveness was seen.

Adjuvant treatment with ursodeoxycholic acid prevents acute rejection in rats receiving heart allografts.

Adjuvant treatment with ursodeoxycholic acid (UDCA) for liver-transplant recipients has been reported to reduce the frequency of acute rejection episodes. To explore this effect further, UDCA was given to rats in an experimental heart transplantation model, with or without concomitant immunosuppressive treatment with antihymocyte globulin (ATG). UDCA was administered orally 7 days before and 14 days after transplantation. Rats treated with UDCA alone or in combination with ATG were compared with untreated controls and ATG-treated recipients. Adjuvant treatment with UDCA was found to induce prolonged graft survival and increase the amount of transplant tolerance in rats. Serum levels of bilirubin and aminotransferases were not altered irrespective of the UDCA dose given. The results indicate that UDCA has an immunomodulatory capacity that might not be restricted to the liver, but also might apply to other transplanted organs as well.