Immunosuppression: evolution in practice and trends, 1994-2004

Roma ethnicity and clinical outcomes in kidney transplant recipients

BACKGROUND

Racial and ethnic disparities among North American patients with chronic kidney disease have received significant attention. In contrast, little is known about health-related outcomes of patients with end-stage renal disease among the Roma minority, also known as gypsies, compared to Caucasian individuals. We prospectively assessed the association between Roma ethnicity and long-term clinical outcomes in kidney transplant recipients.

METHODS

In a prevalent cohort of renal transplant recipients, followed up over a median of 94 months, we prospectively collected socio-demographic, medical (and transplant related) characteristics and laboratory data at baseline from 60 Roma and 1,003 Caucasian patients (mean age 45 (SD = 11) and 49 (SD = 13) years, 33 and 41% women, 18 and 17% with diabetes mellitus, respectively). Survival analyses examined the associations between Roma ethnicity and all-cause mortality and death-censored graft loss or death with functioning renal allograft.

RESULTS

During the follow-up period, 341 patients (32%) died. Two-hundred eighty (26%) patients died with a functioning graft and 201 patients (19%) returned to dialysis. After multivariable adjustments, Roma ethnicity was associated with 77% higher risk of all-cause mortality (Hazard Ratio (HR): 1.77; 95% confidence interval (CI): 1.02, 3.07), two times higher risk of mortality with functioning graft (2.04 [1.17-3.55]) and 77% higher risk of graft loss (1.77 [1.01-3.13]), respectively.

CONCLUSIONS

Roma ethnicity is independently associated with increased mortality risk and worse graft outcome in kidney transplant recipients. Further studies should identify the factors contributing to worse outcomes among Roma patients.

The influence of induction therapy for kidney transplantation after a non-renal transplant

BACKGROUND AND OBJECTIVES

Non-renal transplant recipients who subsequently develop ESRD and undergo kidney transplantation are medically and immunologically complex due to comorbidities, high cumulative exposure to immunosuppressants, and sensitization to alloantigen from the prior transplant. Although prior non-renal transplant recipients are one of the fastest growing segments of the kidney wait list, minimal data exist to guide the use of antibody induction therapy (IT+) at the time of kidney after lung (KALu), heart (KAH), and liver (KALi) transplant.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This retrospective cohort study used national registry data to examine IT use and survival after kidney transplantation. Separate multivariate Cox regression models were constructed to assess patient survival for IT+ and IT- KALu (n=232), KAH (n=588), and KALi (n=736) recipients.

RESULTS

Use of IT increased during the study period. The percentage of patients considered highly sensitized (panel reactive antibody ≥20%) was not statistically significant between IT+ and IT- groups. IT+ was not associated with improvement in 1- and 10-year patient survival for KALu (P=0.20 and P=0.22, respectively) or for KAH (P=0.90 and P=0.14, respectively). However, IT+ among KALi was associated with inferior patient survival at 1 and 10 years (P=0.04 and P=0.02, respectively).

CONCLUSIONS

Use of IT for kidney transplantation among prior non-renal transplant recipients may not offer a survival advantage in KALu or KAH. However, due to limited power, these findings should be interpreted cautiously. IT+ was associated with inferior outcomes for KALi. Use of IT should be judicially reconsidered in this complex group of recipients.

Role of T cell-nuclear factor κB in transplantation

Nuclear factor (NF) κB is a pleiotropic transcription factor that is ubiquitously expressed. After transplantation of solid organs, NF-κB in the graft is activated within a few hours as a consequence of ischemia/reperfusion and then again after a few days in intragraft infiltrating cells during the process of acute allograft rejection. In the present article, we review the components of the NF-κB pathway, their mechanisms of activation, and their role in T cell and antigen-presenting cell activation and differentiation and in solid organ allograft rejection. Targeted inhibition of NF-κB in selected cell types may promote graft survival with fewer adverse effects compared with global immunosuppressive therapies.

How delayed graft function impacts exposure to mycophenolic acid in patients after renal transplantation

INTRODUCTION

Mycophenolic acid (MPA) plasma concentrations are highly variable on standard-dose mycophenolate mofetil therapy. At creatinine clearances below 25 mL/min, MPA clearance increases as a result of a higher nonprotein-bound fraction. Patients with delayed graft function (DGF) after renal transplantation are exposed to low total MPA concentrations, when risk of rejection is highest. This study investigated the influence of DGF on MPA exposure and on clinical outcome.

METHODS

Adult renal transplantation patients treated with mycophenolate mofetil, corticosteroids, and either microemulsified cyclosporine (n = 459) or tacrolimus (n = 371) participated in a randomized controlled trial (the Fixed-Dose Concentration-Controlled [FDCC] Study). Abbreviated MPA areas under the curve (AUCs) were obtained on Day 3, Day 10, Week 4, and Month 3, to calculate MPA AUC₀₋₁₂. Free MPA AUC values were available for a subgroup of patients (n = 269).

RESULTS

The overall incidence of DGF was 187 of 830 (23%) and did not differ between cyclosporine-treated (24%) and tacrolimus- (21%) treated patients. The incidence of biopsy-proven acute rejection at 12 months was significantly higher in patients with DGF (13.8% versus 21.4%). Patients with DGF had significantly lower dose-corrected MPA AUC on Day 3 and Day 10. Free MPA fraction and dose-corrected free MPA AUC were significantly higher in patients with DGF, from Day 3 until Month 3. The total number of patients with at least one opportunistic infection was significantly higher in patients with DGF (33.2%) compared with patients without DGF (25.8%) (P = 0.048). Patients with DGF developing opportunistic infections did not have higher total MPA AUC nor higher free MPA AUC compared with those without opportunistic infections.

CONCLUSION

Patients with DGF have significantly lower dose-corrected MPA AUC in the first month after renal transplantation, presumably as a result of enhanced MPA clearance on account of the elevated MPA free fraction. Because patients with DGF have a higher rate of acute rejection and lower MPA exposure, higher dosing of mycophenolate mofetil in such patients may improve outcome. However, the already increased incidence of opportunistic infections in patients with DGF is a concern.

Comparison of azathioprine with mycophenolate mofetil in a living donor kidney transplant programme

There are conflicting data regarding the comparative efficacy of mycophenolate mofetil (MMF) versus azathioprine (AZA) as maintenance immunosuppressive agent in kidney transplantation. The data are even less in combination with tacrolimus (TAC) in living donor kidney transplantation. A total of 205 living donor kidney transplants, on TAC-based triple drug immunosuppression were included in the study. A total of 113 patients received AZA and rest 92 were on MMF based protocol. TAC levels were monitored and graft biopsy was done whenever rejection was suspected. The outcomes were evaluated in terms acute rejection (AR) episodes at 1 year, infections, renal function, graft loss, and death between two groups. The study group comprised 163 males (79.5%) and 42 (20.5%) females. The mean age of patients was 42.4±11.8 years in the AZA group and 39.4 ±13.4 in the MMF group (P=0.09). The mean duration of follow-up was 491.7±240.7 and 478.8±334.4 days respectively in the AZA and MMF groups (P=0.75). Thirty-seven of 92 (40.2%) patients in the MMF group and 70/113 (61.9%) patients in the AZA group received IL-2 RAb induction (P=0.002). 32 patients (15.6 %) developed AR within a year. The incidence of AR was similar in patients who received MMF (12/92, 13%) and those who received AZA (20/113, 17.5%), (P=0.36). There was no difference in the incidence of AR in the subgroup of patients who received IL-2 RAb compared to those who did not receive induction in the two groups (5/37 vs. 7/55 in the MMF group and 10/70 vs. 10/43 in the AZA group, P=0.72). The incidence of infections was similar in the two groups (19/92, 20.6% vs. 25/113, 22.1%, P=0.79). Three patients developed CMV disease, of which two were in the MMF group. Graft loss occurred in 7/205 (3.4%) and death in 8/205 (3.9%) patients. Six of eight patients who died had functioning grafts. The rate of graft loss (3/92 vs. 4/113, P=0.97) and death (5/92 vs. 3/113, P=0.27) was similar in two groups. The overall patient survival was 94.5% and death censored graft survival was 97.4%. Cost comparison suggests AZA to be 6-10 times cheaper than MMF. This study suggests that, in tacrolimus-based immunosuppression, azathioprine may be as good as MMF as maintenance immunosuppressive drug in living donor kidney transplantation. It is also a more cost-effective immunosuppression.

Immunosuppression: does one regimen fit all?

There has been considerable interest in the individualization of immunosuppressive regimens in an attempt to avoid side effects and improve long-term outcomes. Most available studies have addressed steroid and calcineurin inhibitor minimization in an attempt to prevent the development of chronic allograft dysfunction and cardiovascular mortality. Herein, we evaluate the available evidence for incorporation of these novel strategies in standard clinical care of kidney transplant recipients. Protocol biopsies, pharmacogenetics, and other assays have been developed to guide tailoring of immunosuppression; however, although promising results have been obtained, trials showing their ability to improve long-term outcome are lacking and urgently needed.

Relationship of tacrolimus exposure and mycophenolate mofetil dose with renal function after renal transplantation

INTRODUCTION

The most common immunosuppressive treatment in de novo renal transplantation is a triple regimen that includes tacrolimus, mycophenolate mofetil (MMF) and corticosteroids, and that may also include antibody induction. Whether nephrotoxicity is an issue with tacrolimus at the currently used dosages remains an open question.

METHODS

We pooled data from three large, randomized, de novo renal transplantation studies (Symphony, Fixed Dose Concentration Controlled [FDCC], and OptiCept) that used variations of the triple regimen with respect to tacrolimus target levels, MMF dosing, and antibody induction. We used multivariate linear regression to explore the relationship of renal function at 1 year after transplantation (estimated glomerular filtration rate) with tacrolimus levels and MMF dose measured over the previous 6 months. The model included also a series of possible confounders. RESULTS.: The analysis population consisted of 998 patients. On average, tacrolimus levels were in a range considered low (mean ± standard deviation 7.2 ± 2.54 ng/mL), and MMF dose was 1.5 ± 0.61 g/day. Lower tacrolimus levels and higher MMF doses were associated with significantly better renal function. There were other variables associated with renal function, most notably acute rejection, donor age, and delayed graft function. Subanalyses in each of the three studies gave a consistent picture. There was no overt difference in the effect sizes when patients with stage II (estimated glomerular filtration rate 60-89 mL/min) or stage III (30-59 mL/min) chronic kidney disease were assessed separately.

CONCLUSION

Tacrolimus seems to have a moderate but consistent nephrotoxic effect even in modern efficient immunosuppressive regimens where it is used at lower doses than in previous years.

Genomic-derived markers for early detection of calcineurin inhibitor immunosuppressant-mediated nephrotoxicity

Calcineurin inhibitor (CI) therapy has been associated with chronic nephrotoxicity, which limits its long-term utility for suppression of allograft rejection. In order to understand the mechanisms of the toxicity, we analyzed gene expression changes that underlie the development of CI immunosuppressant-mediated nephrotoxicity in male Sprague-Dawley rats dosed daily with cyclosporine (CsA; 2.5 or 25 mg/kg/day), FK506 (0.6 or 6 mg/kg/day), or rapamycin (1 or 10 mg/kg/day) for 1, 7, 14, or 28 days. A significant increase in blood urea nitrogen was observed in animals treated with CsA (high) or FK506 (high) for 14 and 28 days. Histopathological examination revealed tubular basophilia and mineralization in animals given CsA (high) or FK506 (low and high). We identified a group of genes whose expression in rat kidney is correlated with CI-induced kidney injury. Among these genes are two genes, Slc12a3 and kidney-specific Wnk1 (KS-Wnk1), that are known to be involved in sodium transport in the distal nephrons and could potentially be involved in the mechanism of CI-induced nephrotoxicity. The downregulation of NCC (the Na-Cl cotransporter coded by Slc12a3) in rat kidney following CI treatment was confirmed by immunohistochemical staining, and the downregulation of KS-Wnk1 was confirmed by quantitative real-time-polymerase chain reaction (qRT-PCR). We hypothesize that decreased expression of Slc12a3 and KS-Wnk1 could alter the sodium chloride reabsorption in the distal tubules and contribute to the prolonged activation of the renin-angiotensin system, a demonstrated contributor to the development of CI-induced nephrotoxicity in both animal models and clinical settings. Therefore, if validated as biomarkers in humans, SLC12A3 and KS-WNK1 could potentially be useful in the early detection and reduction of CI-related nephrotoxicity in immunosuppressed transplant patients when monitoring the health of kidney xenographs in clinical practice.

Induction antibody therapy in renal transplantation using early steroid withdrawal: long-term results comparing anti-IL2 receptor and anti-thymocyte globulin

BACKGROUND

The present study intends to investigate the effects of anti-IL2 receptors (anti-IL2R) vs. lymphocyte-depleting agents in the early steroid withdrawal (ESW) scheme.

METHODS

This is a retrospective cohort of 167 consecutive adult renal transplant recipients. Immunosuppression was based on tacrolimus and mycophenolate mofetil. Antibody induction therapy was carried out with lymphocyte-depleting agent (thymoglobulin) or anti-IL2R (Basiliximab or Daclizumab). ESW protocol was performed by administering intravenous methlyprednisolone as follows: 500 mg on day 0, 250 mg on day 1, 125 mg on day 2, 60 mg on day 3, and then stopped.

RESULTS

Among the 167 studied patients, 79 (47.3%) received anti-IL2R and 88 (52.7%) received thymoglobulin induction. Significantly fewer episodes of acute rejection were seen at one year in patients treated with thymoglobulin as compared to anti-IL2R (25.6% vs. 11.4%, p=0.01). At five years, a significant difference in graft survival was observed in anti-IL2R-treated patients compared with thymoglobulin (83.5% vs. 95.5%, p=0.01). Multivariate analysis disclosed that female sex, antibody induction therapy using thymoglobulin and a trough tacrolimus level higher than 10 were protective factors against acute rejection, while there was a trend to increased risk of acute rejection at first year post-transplantation in patients presenting delayed graft function (DGF). Antibody induction was independently associated with patient and graft survival at five years (OR 0.213, 95% CI 0.046-0.991, p=0.04).

CONCLUSION

ESW scheme seems to be safe and its use is beneficial since there are fewer adverse effects. Thymoglobulin induction therapy is associated with fewer rejection episodes. Induction therapy with thymoglobulin is associated with higher patient and allograft survival when comparing with anti-IL2R.

Randomized trial of immunosuppressive regimens in renal transplantation

The optimal long-term regimen for immunosuppression for kidney transplant recipients is unknown. We conducted a randomized trial involving 150 kidney transplant recipients to compare tacrolimus/sirolimus, tacrolimus/mycophenolate mofetil (MMF), and cyclosporine/sirolimus. All patients received daclizumab induction and maintenance corticosteroids. Median follow-up was 8 yr post-transplant. Acute rejection (AR) occurred significantly less often among those treated with tacrolimus/MMF (12%) than among those treated with tacrolimus/sirolimus (30%) or cyclosporine/sirolimus (28%). Mean estimated GFR was consistently higher in the tacrolimus/MMF arm, especially after controlling for donor age in a multivariable model during the first 36 mo (P ≤ 0.008). The rate of dying with a functioning graft was significantly higher among those treated with tacrolimus/sirolimus (26%) than among those treated with tacrolimus/MMF (12%) or cyclosporine/sirolimus (4%). We did not observe significant differences in actuarial graft survival at 8 yr post-transplant between the groups. Patient noncompliance seemed responsible for 45% (13/29) of observed graft failures, with 11 of these occurring after 36 mo. Significantly more viral infections, protocol violations, and need for antilipid therapy occurred among patients receiving sirolimus, but we did not observe differences between the groups with regard to infections requiring hospitalization or new-onset diabetes. Taken together, these results suggest that maintenance therapy with tacrolimus/MMF is more favorable than either tacrolimus/sirolimus or cyclosporine/sirolimus.

The effects of AEB071 (sotrastaurin) with tacrolimus on rat heterotopic cardiac allograft rejection and survival

BACKGROUND

AEB071 (sotrastaurin) is a specific inhibitor of protein kinase C that prevents T-cell activation. Our previous study demonstrated that AEB071 monotherapy could prevent acute cardiac allograft rejection in rats. Herein, we investigated the effects of AEB071 combined with various doses of tacrolimus (Tac) on the allograft rejection and survival in a rat heart transplantation model.

MATERIALS AND METHODS

Heterotopic cardiac transplantation from Brown-Norway to Lewis rats was performed. Cardiac allograft survival was assessed by monitoring heartbeats in six recipients of each experimental group. Another four recipient rats were selectively sacrificed in each group at d 7 post-transplantation for histologic examination. Serum transaminases, blood urea nitrogen, and creatinine concentrations were measured.

RESULTS

AEB071 monotherapy prolonged allograft mean survival time (MST) compared with the untreated control group. Also a combination of AEB071 and Tac prolonged MST compared with monotherapy groups with higher dose of Tac. In the cardiac graft histology, AEB071 combined with Tac 0.6 mg/kg/d significantly decreased the rejection grade as indicative of decreased inflammatory cell infiltration into the graft. No experimental group was found with any abnormal histologic or serologic evidence of liver and kidney toxicity.

CONCLUSION

AEB071 combined with a smaller dosage of Tac may be clinically possible to establish calcineurin inhibitor (CNI) minimization protocol in solid organ transplantation.

Renal Transplantation - An Experience of 500 Patients

BACKGROUND

Renal transplantation is the treatment modality of choice for patients with end stage kidney failure. We present our experience of graft and patient survival of initial 500 renal transplants performed between May 1991 and July 2006, at Army Hospital (R&R).

MATERIAL AND METHODS

All patients received triple drug immunosuppression with cyclosporine/tacrolimus, azathioprine/ mycophenolate mofetil and steroids. Patients in high risk group received induction therapy with IL-2 receptor blockers/anti-thymocyte globulin.

RESULTS

Majority of the recipients (79%) were males, whereas majority of the donors (59.4%) were females. In the donor profile, 385 (77%) transplants were live related, 108 (21.6 %) were spousal and 7 (1.4%) were cadaveric transplants. Mean age of the donors and recipients was 42.11 ± 11.53 years (range 19-72 years) and 33 ± 9.39 years (range 5-60 years) respectively. Eighty two patients (16.4%) were lost to follow up and the present data on rejections, patients and graft survival pertains to 418 patients. These patients have been followed up for a mean period of 2.63 years (SE, 0.122; median 1.8 years; range 0-13.36 years). Acute rejection episodes occurred in 115 (27.3%) patients and 95% of these could be reversed with steroids/ATG. Sixty eight patients (16%) have died on follow-up. Our one-year, 5 year and 10 year estimated graft survival is 95.4% (SE, 0.01), 80.5% (SE, 0.03) and 53.1% (SE, 0.09) respectively and patient survival at one year is 93.2% (SE, 0.01). The estimated graft and patient survival in our series is 9.83 (95% CI, 8.92-10.73) and 9.80 (8.93-10.67) years respectively.

CONCLUSION

This centre's short-term graft survival of 95.4% is comparable to the best centres of the world.

The role of basiliximab in the evolving renal transplantation immunosuppression protocol

Basiliximab is a chimeric mouse-human monoclonal antibody directed against the alpha chain of the interleukin-2 (IL-2) receptor on activated T lymphocytes. It was shown in phase III trials to reduce the number and severity of acute rejection episodes in the first year following renal transplantation in adults and children, with a reasonable cost-benefit ratio. The drug does not increase the incidence of opportunistic infections or malignancies above baseline in patients treated with conventional calcineurin inhibitor-based immunosuppression. In the field of renal transplantation, basiliximab does not increase kidney or patient survival, despite the reduction in the number of rejection episodes. Basiliximab may reduce the incidence of delayed graft function. In comparison with lymphocyte-depleting antibodies basiliximab appears to have equal efficacy in standard immunological risk patients. Recently, IL-2 receptor monoclonal antibodies have been used with the objective of reducing or eliminating the more toxic elements of the standard immunosuppression protocol. Several trials have incorporated basiliximab in protocols designed to avoid or withdraw rapidly corticosteroids, as well as protocols which substitute target-of-rapamycin (TOR) inhibitors for calcineurin inhibitors.

In vivo CYP3A activity is significantly lower in cyclosporine-treated as compared with tacrolimus-treated renal allograft recipients

In vitro studies have identified cyclosporine and tacrolimus as CYP3A inhibitors. In the current study in renal allograft recipients, we used intravenously and orally administered midazolam as a drug probe to assess whether the study drugs at doses that are generally used in clinical practice have differential effects on in vivo hepatic and first-pass CYP3A activities. Systemic and apparent oral midazolam clearance were 24% (269 ± 73 vs. 354 ± 102 ml/min, P = 0.022) and 31% (479 ± 190 vs. 688 ± 265 ml/min, P = 0.013), respectively, lower in cyclosporine-treated patients (n = 20) than in matched tacrolimus-treated patients (n = 20). The latter displayed midazolam clearances similar to those in two larger cohorts of nonmatched tacrolimus-treated patients (n = 58 and n = 80) and to those receiving a calcineurin inhibitor-free regimen (n = 6). This implies that in vivo hepatic and first-pass CYP3A activities are significantly lower in patients receiving cyclosporine than in those receiving tacrolimus, indicating that, at the doses generally used in clinical practice, cyclosporine is the stronger of the two with respect to CYP3A inhibition. This observation has important implications in the context of drug-drug interactions in transplant recipients.

A dimension reduction approach for modeling multi-locus interaction in case-control studies

Studying one locus or one single nucleotide polymorphism (SNP) at a time may not be sufficient to understand complex diseases because they are unlikely to result from the effect of only one SNP. Each SNP alone may have little or no effect on the risk of the disease, but together they may increase the risk substantially. Analyses focusing on individual SNPs ignore the possibility of interaction among SNPs. In this paper, we propose a parsimonious model to assess the joint effect of a group of SNPs in a case-control study. The model implements a data reduction strategy within a likelihood framework and uses a test to assess the statistical significance of the effect of the group of SNPs on the binary trait. The primary advantage of the proposed approach is that the dimension reduction technique produces a test statistic with degrees of freedom significantly lower than a multiple logistic regression with only main effects of the SNPs, and our parsimonious model can incorporate the possibility of interaction among the SNPs. Moreover, the proposed approach estimates the direction of association of each SNP with the disease and provides an estimate of the average effect of the group of SNPs positively and negatively associated with the disease in the given SNP set. We illustrate the proposed model on simulated and real data, and compare its performance with a few other existing approaches. Our proposed approach appeared to outperform the other approaches for independent SNPs in our simulation studies.

Mycophenolate mofetil initiation in renal transplant patients at different times posttransplantation: the TranCept Switch study

BACKGROUND

Despite evidence of favorable long-term effects of mycophenolate mofetil (MMF) in renal transplantation, its introduction at different times posttransplant has not been studied in large cohorts.

METHODS

Single-organ renal allograft recipients (n=2217) who had MMF introduced 6 months to more than 20 years posttransplantation for various reasons were included in TranCept Switch, a multicenter, noninterventional, observational 4-year study. Changes in renal function before and after the introduction of MMF were analyzed.

RESULTS

MMF was introduced because of renal function decline in 43% of patients and poor tolerability with previous treatment in 23% of patients. The change in slope of the calculated glomerular filtration rate (modification of diet in renal diseases formula) regression line before and after MMF initiation was +2.01 mL/min per year (P<0.001) on average. The greatest benefit was noted in patients who received MMF because of renal function decline and in whom calcineurin inhibitor treatment was subsequently reduced or withdrawn (+3.09 mL/min per year). Time from transplantation to MMF introduction influenced the glomerular filtration rate at MMF initiation (slow progressive deterioration) but not the direction of the slope change, which was positive even for late introduction.

CONCLUSION

MMF introduction may be associated with improvement or stabilization of renal function even several years after transplantation.

Cyclosporine a mediates pathogenesis of aggressive cutaneous squamous cell carcinoma by augmenting epithelial-mesenchymal transition: role of TGFβ signaling pathway

Organ transplant recipients (OTRs) develop multiple aggressive and metastatic non-melanoma skin cancers (NMSCs). Yet, the underlying mechanism remains elusive. Employing a variety of immune-compromised murine models, immunoblotting, immunohistochemical and immunofluorescence techniques, we show that human squamous xenograft tumors in nude mice grow faster and become significantly larger in size following treatment with the immunosuppressive drug, cyclosporine A (CsA). Re-injected tumor cells isolated from CsA-treated xenografts continued to form larger tumors in nude mice than those from vehicle-controls and retained the CsA-signatures of calcineurin signaling inhibition. Similar results were obtained when these tumors were grown in SCID-beige mice or in immuno-competent mice inoculated with syngeinic tumor cells. Consistently, tumors in the CsA group manifested enhanced cellular proliferation and decreased apoptosis. Tumors in CsA-treated animals also showed an augmented epithelial-mesenchymal transition (EMT) characterized by an increased expression of fibronectin, α-SMA, vimentin, N-cadherin, MMP-9/-2, snail and twist with a concomitant decrease in E-cadherin. CsA-treated xenograft tumors manifested increased TGFβ1 expression and TGFβ-dependent signaling characterized by increased nuclear p-Smad 2/3. Our data demonstrate that CsA alters the phenotype of skin SCCs to an invasive and aggressive tumor-type by enhancing expression of proteins regulating EMT acting through the TGFβ1 signaling pathway providing at least one unique mechanism by which multiple aggressive and metastatic NMSCs develop in OTRs.

Single and local blockade of interleukin-6 signaling promotes neuronal differentiation from transplanted embryonic stem cell-derived neural precursor cells

Safe and efficient transplantation of embryonic stem (ES) cells to the brain requires that local inflammatory and immune responses to allogeneic grafts are inhibited. To investigate cytokines that affect graft cell survival and differentiation, we used stromal cell-derived inducing activity to induce the differentiation of neural progenitor cells (NPCs) from mouse ES cells and transplanted the NPCs into mouse brain. Examination of surrounding brain tissue revealed elevated expression levels of interleukin (IL)-1β, IL-4, and IL-6 in response to NPC transplantation. Among these, only IL-6 reduced neuronal differentiation and promoted glial differentiation in vitro. When we added anti-IL-6 receptor antibodies to NPCs during transplantation, this single and local blockade of IL-6 signaling reduced the accumulation of host-derived leukocytes, including microglia. Furthermore, it also promoted neuronal differentiation and reduced glial differentiation from the grafted NPCs to an extent similar to that with systemic and continuous administration of cyclosporine A. These results suggest that local administration of anti-IL-6 receptor antibodies with NPCs may promote neuronal differentiation during the treatment of neurological diseases with cell replacement therapy.

Survival of living-related kidney graft recipients in the era of modern immunosuppressive treatment

BACKGROUND AND OBJECTIVES

Currently, there is no consensus about immunosuppressive therapy following kidney transplantation. Acute rejection rates and allograft survival rates are the clinical outcomes traditionally used to compare the efficacy of various immunosuppressive regimens. Therefore, we conducted this study to evaluate whether patient survival rates improved in the era of modern immunosuppressive treatment during living-related kidney transplantation.

DESIGN AND SETTING

Retrospective cohort study in a university-based tertiary internal medicine teaching hospital performed between 1999 and 2009 and patients followed up to 7 years.

PATIENTS AND METHODS

Survival rates were assessed in 38 patients receiving basiliximab and mycophenolate mofetil (regimen A) and 32 patients receiving antithymocyte globulin and azathioprine (regimen B). The rest of the regimen (cyclosporine A and steroids) remained the same. A secondary end point was acute rejection episode.

RESULTS

Seven-year survival rates were 100% and 72% (P=.001) and 7-year acute rejection-free survival rates were 82% and 53% (P=.03), in groups A and B, respectively.

CONCLUSION

Long-term survival after living-related kidney transplantation has improved in the era of modern immunosuppressive treatment.

CD40-specific costimulation blockade enhances neonatal porcine islet survival in nonhuman primates

The widespread clinical implementation of alloislet transplantation as therapy for type 1 diabetes has been hindered by the lack of suitable islet donors. Pig-to-human islet xenotransplantation is one strategy with potential to alleviate this shortage. Long-term survival of porcine islets has been achieved using CD154-specific antibodies to interrupt the CD40/CD154 costimulation pathway; however, CD154-specific antibodies seem unlikely candidates for clinical translation. An alternative strategy for CD40/CD154 pathway interruption is use of CD40-specific antibodies. Herein, we evaluate the ability of a chimeric CD40-specific monoclonal antibody (Chi220) to protect islet xenografts. Neonatal porcine islets (~50,000 IEQ/kg) were transplanted intraportally into pancreatectomized diabetic macaques. Immunosuppression consisted of induction therapy with Chi220 and the IL-2 receptor-specific antibody basiliximab, and maintenance therapy with sirolimus and the B7-specific fusion protein belatacept. Chi220 effectively promoted xenoislet engraftment and survival, with five of six treated recipients achieving insulin-independent normoglycemia (median rejection-free survival 59 days; mean 90.8 days, maximum 203 days). No thromboembolic phenomena were observed. CD40 represents a promising alternative to CD154 as a therapeutic target, and the efficacy of CD40-specific antibodies in islet xenotransplantation warrants further investigation.

Operative risks of domino liver transplantation for the familial amyloid polyneuropathy liver donor and recipient: a double analysis

Although domino liver transplantation (LT) is an established procedure, data about the operative risks are limited. This study aimed at evaluating the operative risks of domino LT. Two retrospective analyses were conducted (comparison of familial amyloid polyneuropathy [FAP] liver donors [61 patients] vs. FAP nondonors [39 patients] and FAP liver recipients [61 patients] vs. deceased donor liver recipients [61 patients]). First analysis showed a 60-day mortality of 6.6% for FAP donors and 7.7% for FAP nondonors (p = 1.0). No patient developed primary graft nonfunction. Acute rejection was higher in FAP nondonors compared to FAP donors (38.5% vs. 13.1%). Both groups had similar vascular and biliary complication rates. ICU stay was similar, whereas total hospitalization was longer for FAP nondonors. Both groups had similar 1- and 5-year patient and graft survival rates (83.4% vs. 87.2%, and 79.8% vs. 71.8%, p = 0.7) and (83.3% vs. 87.2%, and 79.1% vs.71.8%, p = 0.7). The second analysis showed a 1.6% mortality for FAP liver recipients vs. 3.2% of the control group (p = 1). Both groups had similar morbidity and technical complication rates (18.0% vs. 13.1%, p = 0.45) and (0.18 vs. 0.15, p = 0.65). The domino procedure does not add any risk to FAP donor or recipient. It increases the organ pool allowing transplantation of marginal recipients who otherwise are denied deceased donor liver transplantation.

Pharmacokinetics of once- versus twice-daily tacrolimus formulations in kidney transplant patients receiving expanded criteria deceased donor organs: a single-center, randomized study

BACKGROUND

Noncompliance to immunosuppressive treatment is 1 of the risk factors for kidney graft loss. The once-daily, prolonged-release tacrolimus formulation may improve treatment adherence. We sought to compare the pharmacokinetics of both tacrolimus formulations in older de novo recipients of a cadaveric renal transplant from an expanded-criteria donor.

PATIENTS AND METHODS

This randomized study included 27 patients (14 on once daily prolonged-release formulation [QD] and 13, on the twice-daily formulation [BID]), who were treated with 0.1 mg/kg per day of tacrolimus (target blood level, 5-8 ng/mL) mycophenolate mofetil prednisone and basiliximab induction.

RESULTS

At 24 hours, in combination with the blood levels were 4.70±2.50 versus 4.70±3.04 ng/mL (P=NS). There were no significant differences in the AUC0-24 of tacrolimus (QD/BID) at 3 days (300.8±60.15 vs 287.7±125.78 ng.h/mL) or 21 days (303.05±99.79 vs 275.26±75.37 ng.h/mL), nor in blood levels (ng/mL) at 1 month (8.76±2.46 vs 8.8±1.89), 3 months (7.30±1.72 vs 8.80±1.89) and 6 months (7.19±1.89 vs 6.60±1.71). At 3 days, there was a strong correlation between AUC0-24 and Cmin both for tacrolimus QD (r=.872) and BID (r = 1.0). The incidences of acute rejection episodes were: 0% versus 16.6%; graft survivals, 100% versus 92.3% (P=NS); and patient survivals, both 100%.

CONCLUSION

For older de novo recipients of kidneys from expanded criteria donors tacrolimus QD is comparable to the same dose in the BID formulation with similar at least short-term transplant outcomes.

Risk factors for early-onset and late-onset post-transplant lymphoproliferative disorder in kidney recipients in the United States

Solid-organ transplant recipients have an elevated risk for some malignancies because of the requirement for immunosuppression [1]. In particular, non-Hodgkin's lymphoma (NHL) is common and comprises one end of a spectrum of post-transplant lymphoproliferative disorder (PTLD) ranging from benign hyperplasia to lymphoid malignancy [2]. PTLD risk is influenced by the type of organ transplanted, the age and Epstein-Barr virus (EBV) serostatus of the transplant recipient, and the intensity of immunosuppression [3-9]. PTLD incidence is high immediately after transplantation, decreases subsequently, and then rises again 4-5 years from transplantation [10,11]. This incidence pattern suggests the presence of separate early-onset and late-onset PTLD subtypes. Early-onset PTLDs tend to be EBV-positive and, when extranodal, are more likely than late-onset PTLDs to be localized to the transplanted organ [12,13]. Late-onset PTLD is less likely to be associated with EBV and, overall, is more likely than early-onset PTLD to be extranodal [13,14]. The Scientific Registry of Transplant Recipients (SRTR) includes data on a large number of solid-organ transplant recipients in the United States and information on malignancies diagnosed post-transplantation. We used these data to conduct a retrospective cohort study among kidney transplant recipients to examine differences in risk factors between early-onset PTLD and late-onset PTLD.

CYP3A5 *1 allele: impacts on early acute rejection and graft function in tacrolimus-based renal transplant recipients

BACKGROUND

Tacrolimus is a major immunosuppressant, which has a narrow therapeutic range and wide interindividual variation. The effects of genetic polymorphisms of cytochrome P450 3A (CYP3A) 5 and Adenosine triphosphate-binding cassette subfamily B member 1 (ABCB1) genes on the achievement of target tacrolimus trough levels and clinical outcomes in renal transplants were evaluated.

METHODS

A total of 62 patients participated in this prospective study. After an initial fixed oral dose (0.08 mg/kg two times per day), tacrolimus doses were adjusted to a target range based on daily measurement of blood trough concentration. Every patient underwent 10-day scheduled biopsy. Both the patients and investigators were blinded for the genetic polymorphisms.

RESULTS

Those subjects expressing CYP3A5 (n=29) evidenced significantly lower tacrolimus trough levels between days 1 and 5 after transplantation, when compared with nonexpressers (n=33). Significantly higher overall incidences of early T-cell-mediated rejection (TCR) of at least Banff grade 1 in severity (P=0.017), including clinical rejection within 10 days and subclinical rejection in biopsies at postoperative day 10 were detected in CYP3A5 expressers. The severity of TCR according to Banff '07 classification was associated with CYP3A5 genotypes (P=0.012). Moreover, multivariate analysis identified CYP3A5 expression as an independent risk factor for TCR (odds ratio: 2.79; P=0.043). Significantly lower estimated glomerular filtration rates until 1 month and numerically lower estimated glomerular filtration rates by 12 months were noted in the CYP3A5 expressers. The genetic polymorphisms of the ABCB1 genes exerted no significant effects.

CONCLUSION

We confirmed the significant effects of CYP3A5 polymorphism on the achievement of target tacrolimus trough levels and the development of acute rejection in early period after transplantation and consequent renal allograft function.

Elderly Transplant Recipients

While the total number of organs transplanted in this country has increased over the years, there is still an ever-widening gap between the need for organs and our capacity to meet that need as the overall waiting list continues to grow. This is due in part to significant advances in transplant techniques and outcomes such that Americans with organ failure now seek transplants in greater numbers. Additionally, life-expectancy gains in the United States are creating an aging population who are more likely to suffer organ failure than younger Americans. The national transplant waiting list has continued to shift toward older candidates. The Scientific Registry of Transplant Recipients (SRTR) reported that at the end of 2007, 59.7% of all 97,248 candidates on the waiting list for all organs were 50 years old or older, and 14.9% were 65 years or older. These percentages are substantially higher than they were in 1998 (41.5 and 8.1%, respectively) [1].

Preclinical evaluation of tacrolimus colloidal dispersion for inhalation

Substantial improvements in transplant therapy have been made in the past four decades resulting in the acceptance of organ transplantation as a viable treatment for late-stage disease and organ failure. More recently, lung transplantation has gained acceptance; however, high incidence of chronic rejection and opportunistic infections has limited success rates in comparison with other transplant procedures. To achieve more targeted therapy, pulmonary administration of nebulized tacrolimus (TAC) colloidal dispersion once daily for 28 consecutive days in Sprague Dawley (SD) rats has been investigated for safety and systemic elimination. A liquid dispersion of colloidal TAC and lactose (1:1 ratio by weight) was aerosolized using a vibrating mesh nebulizer and administered via a nose-only dosing chamber. Blood chemistry and histological comparisons to saline-dosed animals showed no clinically significant differences in liver and kidney function or lung tissue damage. Maximum blood and lung concentrations sampled 1h after the final dose showed TAC concentrations of 10.1 ± 1.4 ng/mL and 1758.7 ± 80.0 ng/g, respectively. Twenty-four hours after the final dose, systemic TAC concentrations measured 1.0 ± 0.5 ng/mL, which is well below clinically accepted trough concentrations (5-15 ng/mL) for maintenance therapy, and therefore, would not be expected to induce toxic side effects. The propensity for pulmonary retention seen when compared to single dose lung levels may be due to macrophage uptake and the lipophilic nature of TAC. Additionally, three month stability testing of TAC powder for reconstitution showed no changes in amorphous nature or drug potency when stored at ambient conditions. TAC colloidal dispersion proved to be non-toxic when administered by pulmonary inhalation to SD rats over 28 days while providing therapeutic concentrations locally. This delivery strategy may prove safe and effective for the prevention of lung allograft rejection in lung transplant recipients.

Kidney graft outcomes in living-related transplantation have improved with substitution of basiliximab and mycophenolate mofetil for antithymocyte globulin and azathioprine: a single center retrospective cohort study

BACKGROUND

Despite significant reduction in acute rejection rates and improvements in one year kidney allograft outcomes over the past decade, there is an overall lack of improvement in long-term allograft outcomes. We conducted this study to evaluate whether immunosuppressive regimens involving basiliximab and mycophenolate mofetil improved allograft outcomes in living-related kidney transplantation beyond the first year.

METHODS

In a retrospective cohort study we analyzed kidney graft survival, acute rejection-free survival, kidney function, delayed graft function, and primary non-function in patients receiving an immunosuppressive regimen that included basiliximab and mycophenolate mofetil (group A), and compared to patients receiving antithymocyte globulin and azathioprine (group B). The rest of the treatment protocols remained the same, including cyclosporine A and steroids in both groups.

RESULTS

Seven-year graft survival rates in groups A and B were 83% and 44%, respectively (p=0.005), 7-year acute rejection-free survival rates were 82% and 53%, respectively (p=0.03), kidney function was better (p=0.004) and its deterioration rate was lower (p=0.006) in patients receiving regimen A. In group A 1 primary non-function event was observed in contrast to 4 composite events of delayed graft function and primary non-function in group B (p>0.05).

CONCLUSION

Long-term graft outcomes in living-related kidney transplantation have improved with substitution of basiliximab and mycophenolate mofetil for antithymocyte globulin and azathioprine in immunosuppressive protocols.

The impact of IL2ra induction therapy in kidney transplantation using tacrolimus- and mycophenolate-based immunosuppression

BACKGROUND

IL2 receptor antagonist (IL2ra) induction therapy has gained favor due to an excellent safety profile and improved outcomes in randomized trials using cyclosporine-based immunosuppression. However, there have been no large randomized trials or retrospective analyses examining the effect of IL2ra versus no induction using tacrolimus and mycophenolate (TAC/MPA)-based therapy.

METHODS

A retrospective analysis from the Scientific Renal Transplant Registry of adult, primary kidney transplant recipients from 2000 to 2008 with initial immunosuppression of TAC/MPA and prednisone, who received IL2ra induction therapy or no induction therapy (n=28,686) was performed. The primary outcome was acute rejection at 1 year, and secondary outcomes were graft and patient survival at 1 and 3 years. Multivariable analysis was used to control for factors shown to influence the incidence of acute rejection, and separate analyses were performed for deceased versus living donors.

RESULTS

Acute rejection at 1 year was significantly lower with IL2ra (11.6%) versus no induction therapy (13.0%; P=0.001). One-year (95.7% vs. 95.8%) and 3-year (87.5% vs. 87.8%) graft survival, and 1-year (97.4% vs. 97.5%) and 3-year (92.8% vs. 93.2%) patient survival, was not different between those receiving IL2ra and no induction therapy. On multivariable analysis, the relative risk of acute rejection with IL2ra was 0.90 (95% CI, 0.85-0.96; P=0.001), and the effect was greater in living donors (relative risk, 0.82; P<0.001) than deceased donors (relative risk, 0.95; P=0.23).

CONCLUSION

The benefit of IL2ra induction with TAC/MPA/prednisone maintenance immunosuppression is less than previously reported due to a low baseline incidence of acute rejection.

Reduced C0 concentrations and increased dose requirements in renal allograft recipients converted to the novel once-daily tacrolimus formulation

BACKGROUND

Recently, a once-daily prolonged release formulation of tacrolimus (TacOD) has been approved for the prevention of renal allograft rejection. Studies reported equivalent area under the concentration-time curve0-24 and predose trough (C0) concentrations when compared with the standard twice-daily tacrolimus (Tac) formulation. Hence, the package insert advices a 1:1 mg conversion. Here, we report our independent experience with conversion to TacOD according to the manufacturer's instructions.

METHODS

Retrospective single-center study evaluating the evolution of C0 concentrations and dose requirements after conversion to TacOD in 284 renal allograft recipients. Potential clinical, biochemical, and genetic determinants of changes in C0 concentrations and dose requirements after conversion were explored in univariate and multivariate analyses.

RESULTS

After conversion, C0 concentrations decreased significantly (-1.36+/-2.51 microg/L or -12.66%+/-24.36%, P<0.0001). In 38.3% of patients, this decrease exceeded 20%. TacOD dose was increased in 52.5% of patients. Average dose requirements increased to 0.71+/-1.78 mg/day or 14.68%+/-28.87% (P<0.0001). In 28.0% of patients, dose requirements increased more than 20%. Dose changes were more profound in patients converted within 1 year after transplantation, and in this subgroup (n=78), higher creatinine and lower hemoglobin levels were associated with a larger increase in dose requirements in multivariate analysis (r=0.35, P<0.0001). Despite dose adjustments, average C0 concentrations remained 9.09%+/-28.85% lower after conversion (P<0.0001).

CONCLUSIONS

Conversion from standard twice-daily tacrolimus formulation to TacOD on a 1:1 mg basis results in reduced Tac C0 concentrations and increased dose requirements. Thus, conversion is not as straightforward as suggested by the manufacturer, and converted patients should be monitored strictly until stable C0 concentrations are achieved.

Sotrastaurin and cyclosporine drug interaction study in healthy subjects

INTRODUCTION

Sotrastaurin is an immunosuppressant that inhibits protein kinase C and blocks T-lymphocyte activation. The authors determined the effect of combining sotrastaurin with the calcineurin inhibitor cyclosporine on the pharmacokinetics and biomarker responses to both drugs.

METHODS

This was a randomized, 4-period, crossover study in 20 healthy subjects who received single oral doses of (1) sotrastaurin 100 mg, (2) cyclosporine 400 mg, (3) 100 mg sotrastaurin with 100 mg cyclosporine and (4) 100 mg sotrastaurin with 400 mg cyclosporine. Blood samples were collected to measure drug levels and biomarkers of T-lymphocyte activation (interleukin-2 and tumor necrosis factor producing T-cells and interleukin-2 messenger RNA levels) and of T-lymphocyte proliferation (thymidine uptake).

RESULTS

Sotrastaurin did not alter cyclosporine AUC; however, low-dose and high-dose cyclosporine increased sotrastaurin AUC by 1.2-fold [90% confidence interval, 1.1-1.4] and 1.8-fold [1.6-2.1], respectively. Adding high-dose cyclosporine to a low-therapeutic dose of sotrastaurin significantly enhanced the inhibition of cytokine production by 31% [95% confidence interval, 25-36%], of interleukin-2 messenger RNA levels by 13% [7-19%], and of thymidine uptake by 37% [32-42%] compared with sotrastaurin alone. Addition of low-dose cyclosporine elicited slightly lower enhancements in inhibition by 21% [14-28%], 6% [-4-16%], and 26% [21-30%], respectively, compared with sotrastaurin alone.

CONCLUSIONS

Sotrastaurin did not alter the pharmacokinetics of cyclosporine, but cyclosporine increased sotrastaurin AUC up to 1.8-fold. The combined drugs elicited a significantly greater inhibition of T-cell activation and proliferation than sotrastaurin alone.

A risk prediction model for delayed graft function in the current era of deceased donor renal transplantation

Delayed graft function (DGF) impacts short- and long-term outcomes. We present a model for predicting DGF after renal transplantation. A multivariable logistic regression analysis of 24,337 deceased donor renal transplant recipients (2003-2006) was performed. We developed a nomogram, depicting relative contribution of risk factors, and a novel web-based calculator (http://www.transplantcalculator.com/DGF) as an easily accessible tool for predicting DGF. Risk factors in the modern era were compared with their relative impact in an earlier era (1995-1998). Although the impact of many risk factors remained similar over time, weight of immunological factors attenuated, while impact of donor renal function increased by 2-fold. This may reflect advances in immunosuppression and increased utilization of kidneys from expanded criteria donors (ECDs) in the modern era. The most significant factors associated with DGF were cold ischemia time, donor creatinine, body mass index, donation after cardiac death and donor age. In addition to predicting DGF, the model predicted graft failure. A 25-50% probability of DGF was associated with a 50% increased risk of graft failure relative to a DGF risk < 25%, whereas a > 50% DGF risk was associated with a 2-fold increased risk of graft failure. This tool is useful for predicting DGF and long-term outcomes at the time of transplant.

Process of care events in transplantation: effects on the cost of hospitalization

Deviations in the processes of healthcare delivery that affect patient outcomes are recognized to have an impact on the cost of hospitalization. Whether deviations that do not affect patient outcome affects cost has not been studied. We have analyzed process of care (POC) events that were reported in a large transplantation service (n = 3,012) in 2005, delineating whether or not there was a health consequence of the event and assessing the impact on hospital resource utilization. Propensity score matching was used to adjust for patient differences. The rate of POC events varied by transplanted organ: from 10.8 per 1000 patient days (kidney) to 17.3 (liver). The probability of a POC event increased with severity of illness. The majority (81.5%) of the POC events had no apparent effect on patients' health (63.6% no effect and 17.9% unknown). POC events were associated with longer length of stay (LOS) and higher costs independent of whether there was a patient health impact. Multiple events during the same hospitalization were associated with the highest impact on LOS and cost. POC events in transplantation occur frequently, more often in sicker patients and, although the majority of POC events do not harm the patient, their effect on resource utilization is significant.

The anti-fibrotic effect of mycophenolic acid-induced neutral endopeptidase

Mycophenolic acid (MPA) appears to have anti-fibrotic effects, but the molecular mechanisms underlying this are unknown. We prospectively studied 35 stable kidney transplant recipients maintained on cyclosporine and azathioprine. We converted 20 patients from azathioprine to enteric-coated mycophenolate sodium (EC-MPS) and continued the remaining 15 patients on azathioprine. Exploratory mRNA expression profiling, performed on five randomly selected EC-MPS patients, revealed significant upregulation of neutral endopeptidase (NEP), which is an enzyme that degrades angiotensin II. We confirmed these microarray data by measuring levels of NEP expression in all subjects; in addition, we found that NEP gene expression correlated inversely with proteinuria. In an additional 33 patients, glomerular and tubular NEP protein levels from renal graft biopsies were significantly higher among the 13 patients receiving cyclosporine + EC-MPS than among the 12 patients receiving cyclosporine + azathioprine or 8 patients receiving cyclosporine alone. Glomerular NEP expression inversely correlated with glomerulosclerosis and proteinuria, and tubular NEP expression inversely correlated with interstitial fibrosis. Incubation of human proximal tubular cells with MPA increased NEP gene expression in a dose- and time-dependent manner. Moreover, MPA reduced angiotensin II-induced expression of the profibrotic factor plasminogen activator inhibitor-1, and a specific NEP inhibitor completely reversed this effect. Taken together, our data suggest that MPA directly induces expression of neutral endopeptidase, which may reduce proteinuria and slow the progression of renal damage in kidney transplant recipients.

From cancer to transplantation: an evaluation of period analysis for calculating up-to-date long-term survival estimates

The timeliness of survival monitoring is particularly important in a field such as transplantation medicine, where progress occurs rapidly. Period analysis, a method successfully applied for improving the timeliness of survival monitoring in population-based cancer survival analysis, could potentially be useful in the field of transplantation as well. Using data from the Collaborative Transplant Study, the authors compared the ability of traditional, cohort-based analysis methods and the period analysis method to provide timely 5-year graft and patient survival estimates for kidney, heart, and liver transplants in 6 age groups (0-17, 18-29, 30-39, 40-49, 50-59, >or=60 years) on 378 occasions between 1990-1992 and 2000-2002. Overall, period estimates provided superior predictions for the survival of most recent transplants on 344 of 378 occasions (91%); in the organ-specific analysis, this proportion ranged between 83% for heart and 100% for kidney graft survival. This evaluation provides evidence that the period analysis method can improve the timeliness of survival monitoring in solid organ transplantation. The method appears useful for providing more up-to-date long-term survival estimates than traditional methods, and its use in pertinent studies is encouraged.

Ten-year graft survival of deceased-donor kidney transplantation: a single-center experience

BACKGROUND

Kidney transplantation is the treatment of choice for end-stage renal disease that restores the patients' quality of life and reduces the morbidity and mortality rates induced by renal failure and its complications. However, after transplantation the organ and patient survival rates are important issues of interest in many centers worldwide.

SUBJECTS AND METHODS

This is a historical cohort study planned to determine the organ survival rate after kidney transplantation from deceased donor during a period of 10 years (March 1999-March 2009) in Shiraz Transplant Center, Namazi Hospital, Shiraz, Iran. We tried to clarify the probable contributory risk factors implicating in graft loss. Kaplan-Meier method was used to determine the survival rate. Log-rank test was used to compare survival curves, and Cox regression model to define the hazard ratio and for modeling of factors implicating in survival rate.

RESULTS

Mean follow-up period was 37.54 +/- 28.6 months. Allograft survival rates at 1, 3, 5, and 9 years after kidney transplantation from deceased donor (calculated by Kaplan-Meier method) was found to be 93.7, 89.1, 82.1, and 80.1%, respectively. Duration of dialysis before operation and creatinine level at discharge were showed to be the most important factors influencing survival rate of renal allograft.

CONCLUSION

Overall long-term graft survival in our cohort is satisfactory and comparable with reports from large centers in the world. Duration of dialysis before operation and creatinine level at discharge are the only independent factors that could correlate with long-term graft survival in our cohort.

Immunosuppression in simultaneous pancreas-kidney transplantation: progress to date

Simultaneous pancreas-kidney transplantation (SPKT) is the treatment of choice for patients with end-stage renal failure due to type 1 diabetes mellitus. With advances in surgical techniques and immunosuppression management, outcomes have improved, with current 1- and 10-year pancreas graft survival rates of 86% and 53%, respectively. Induction therapy with either alemtuzumab or rabbit antithymocyte globulin (rATG) in combination with a calcineurin inhibitor (CNI) and mycophenolate mofetil (MMF) or sirolimus appears to be safe and effective in the setting of rapid steroid withdrawal (RSW), with excellent graft survival and low rejection rates. There are no large randomized trials between alemtuzumab and rATG to determine whether one is better than the other. Anti-interleukin (IL)-2 receptor antibody induction and no induction in combination with a CNI, MMF or sirolimus, and prednisone have demonstrated excellent graft survival rates but are associated with a higher incidence of acute rejection. The efficacy of anti-IL-2 receptor antibodies or no induction in the setting of RSW is unproven. Both of the CNIs, ciclosporin and tacrolimus, are effective in preventing acute rejection in SPKT recipients; however, pancreas allograft survival may be better with tacrolimus. MMF is more effective than azathioprine in preventing acute rejection. Sirolimus appears to be effective in preventing acute rejection, but the combination of sirolimus with a CNI may accentuate the nephrotoxicity of the CNI. RSW with induction therapy is safe and effective in SPKT recipients, but longer follow-up data on outcomes are needed. Recent analysis of registry data shows that most transplant centres are using an induction agent followed by a combination of tacrolimus, MMF and corticosteroids in SPKT recipients.