Donor-derived urologic cancers after renal transplantation: A retrospective non-randomized scientific analysis.

BACKGROUND: Malignancies in the urinary tract and the kidney graft are quite common after kidney transplantation. In some selected cases tumours develop from donor-derived tissue. OBJECTIVES: We hypothesised that there is a clinical value to investigate donor/recipient origin in urologic malignancies in renal transplant recipients. METHODS: In this retrospective study, including patients transplanted between the years 1969 and 2014 at Uppsala University Hospital, Sweden, 11 patients with malignancies in urinary tract and 4 patients with malignancies in kidney transplants were investigated. Donor/recipient origin of tumour tissue was analysed by polymerase chain reaction (PCR) of human leucocyte antigen (HLA) genotypes or by fluorescence in situ hybridization (FISH analysis) of sex chromosomes. HLA genotype and sex chromosomes of the tumour were compared to the known HLA genotype and sex chromosomes of recipient and donor. RESULTS: Three of ten cancers in the urinary tract and three of four cancers in the kidney transplants were donor-derived. CONCLUSIONS: We suggest that urologic malignancies in renal transplant recipients can be investigated for transplant origin. In addition to conventional therapy the allograft immune response against these tumours can be valuable to treat donor-derived cancers.

Prior antithymocyte globulin therapy and survival in post-transplant lymphoproliferative disorders.

Background: Treatment with antithymocyte globulin (ATG) is a well-recognized risk factor for the development of post-transplant lymphoproliferative disorders (PTLD) after solid organ transplantation, but it is unknown how its use affects overall survival after PTLD.Methods: A total of 114 patients with PTLD and available data on immunosuppressive regimen were included from a nation-wide case series of solid organ transplant recipients in Sweden. Prior use of ATG was correlated to clinical features, PTLD subtype, and survival.Results: A total of 47 (41%) patients had received ATG prior to the diagnosis of PTLD. The ATG-treated patients were more likely to be recipients of hearts or lungs, and less likely of kidneys (p < 0.01). They had experienced more acute rejections (p = 0.02). The PTLDs arose earlier, median 2.0 vs. 6.6 years post-transplant (p = 0.002) and were more often situated in the allograft (32% vs. 7%, p < 0.001) in patients with prior ATG vs. no ATG treatment. The PTLDs in the ATG group were more often Epstein-Barr virus-positive (80% vs. 40%, p < 0.001). There were more polymorphic PTLDs (17% vs. 1.5%, p = 0.004) and less T-cell PTLDs (4% vs. 19%, p = 0.02) in the ATG group than in the no ATG group. Diffuse large B-cell lymphoma was equally common in patients with and without prior ATG therapy, but the non-germinal center subtype was more frequent in the ATG group (p = 0.001). In an adjusted Cox proportional hazards regression model, prior ATG treatment and better performance status were associated with superior overall survival, whereas older age, T-cell subtype of PTLD, presence of B symptoms, and elevated lactate dehydrogenase were associated with inferior overall survival. Patients receiving ATG solely as rejection therapy had superior overall survival compared with those receiving ATG as induction therapy or both (p = 0.03).Conclusions: ATG therapy, especially rejection therapy, prior to PTLD development is an independent prognostic factor for superior overall survival after PTLD diagnosis.

Intratumoral immunostimulatory AdCD40L gene therapy in patients with advanced solid tumors.

AdCD40L is a replication-deficient virus carrying the gene for CD40 ligand which has previously been evaluated in patients with urothelial cancer and malignant melanoma. Herein, we present the results of repeated intratumoral injections of AdCD40L in seven patients with metastatic solid cancer. One patient who developed urothelial cancer derived from a renal transplant was treated with repeated injections of AdCD40L alone. The remaining patients suffered from cholangiocarcinoma, kidney, breast, rectal, or ovarian cancer and received AdCD40L repeatedly (4x) in combination with cyclophosphamide. The treatment was safe and generally well-tolerated. Two patients had clinical benefit of the treatment and one of them was accepted for re-treatment. Circulating proinflammatory cytokines were commonly increased after treatment, but save for TNFα, significances were not reached which could be due to the low number of patients. Similar to earlier findings in AdCD40L-treated melanoma patients, IL8 plasma levels were high in the present study. In conclusion, gene therapy by repeated intratumoral AdCD40L injections alone, or in combination with cyclophosphamide, is feasible and safe in patients with solid cancers. The potential of intratumoral CD40L gene transfer as treatment of cancer was illustrated by the clinical improvement in two out of seven patients.

Safety and efficacy of eculizumab for the prevention of antibody-mediated rejection after deceased-donor kidney transplantation in patients with preformed donor-specific antibodies.

The presence of preformed donor-specific antibodies in transplant recipients increases the risk of acute antibody-mediated rejection (AMR). Results of an open-label single-arm trial to evaluate the safety and efficacy of eculizumab in preventing acute AMR in recipients of deceased-donor kidney transplants with preformed donor-specific antibodies are reported. Participants received eculizumab as follows: 1200 mg immediately before reperfusion; 900 mg on posttransplant days 1, 7, 14, 21, and 28; and 1200 mg at weeks 5, 7, and 9. All patients received thymoglobulin induction therapy and standard maintenance immunosuppression including steroids. The primary end point was treatment failure rate, a composite of biopsy-proved grade II/III AMR (Banff 2007 criteria), graft loss, death, or loss to follow-up, within 9 weeks posttransplant. Eighty patients received transplants (48 women); the median age was 52 years (range 24-70 years). Observed treatment failure rate (8.8%) was significantly lower than expected for standard care (40%; P < .001). By 9 weeks, 3 of 80 patients had experienced AMR, and 4 of 80 had experienced graft loss. At 36 months, graft and patient survival rates were 83.4% and 91.5%, respectively. Eculizumab was well tolerated and no new safety concerns were identified. Eculizumab has the potential to provide prophylaxis against injury caused by acute AMR in such patients (EudraCT 2010-019631-35).

Perfusion of Porcine Kidneys With Macromolecular Heparin Reduces Early Ischemia Reperfusion Injury.

BACKGROUND: Previously, we have been able to demonstrate the possibility of coating the inner surface of the renal arteries in porcine kidneys with a heparin conjugate during hypothermic machine perfusion (HMP). The purpose of this study was to assess the efficacy of this treatment in reducing early ischemia-reperfusion injury. METHOD: Brain death was induced in male landrace pigs by stepwise volume expansion of an epidural balloon catheter until negative cerebral perfusion pressure (CPP) was obtained. Both kidneys (matched pairs; n = 6 + 6) were preserved for 20 hours by HMP during which 50 mg heparin conjugate was added to one of the HMP systems (treated group). A customized ex vivo normothermic oxygenated perfusion (NP) system with added exogenous creatinine was used to evaluate early kidney function. Blood, urine and histological samples were collected during the subsequent 3 hours of NP. RESULTS: Kidney weight was lower at the end of NP (P = 0.017) in the treated group compared with control kidneys. The rate of decline in creatinine level was faster (P = 0.024), total urinary volume was higher (P = 0.031), and the level of urine neutrophil gelatinase-associated lipocalin (NGAL) was lower (P = 0.031) in the treated group. Histologically, less tubular changes were seen (P = 0.046). During NP intrarenal resistance remained lower (P < 0.0001) in the treated group. CONCLUSIONS: Perfusion of porcine kidneys with heparin conjugate during HMP reduces preservation injury and improves organ function shortly after reperfusion. No increased risk of bleeding was seen in this setup. This protective strategy may potentially improve the quality of transplanted kidneys in the clinical setting.

IgG Endopeptidase in Highly Sensitized Patients Undergoing Transplantation.

BACKGROUND: Donor-specific antibodies create an immunologic barrier to transplantation. Current therapies to modify donor-specific antibodies are limited and ineffective in the most highly HLA-sensitized patients. The IgG-degrading enzyme derived from Streptococcus pyogenes (IdeS), an endopeptidase, cleaves human IgG into F(ab')2 and Fc fragments inhibiting complement-dependent cytotoxicity and antibody-dependent cellular cytotoxicity, which suggests that IdeS might be useful for desensitization. We report on the combined experience of two independently performed open-label, phase 1-2 trials (conducted in Sweden and the United States) that assessed the efficacy of IdeS with regard to desensitization and transplantation of a kidney from an HLA-incompatible donor. METHODS: We administered IdeS to 25 highly HLA-sensitized patients (11 patients in Uppsala or Stockholm, Sweden, and 14 in Los Angeles) before the transplantation of a kidney from an HLA-incompatible donor. Frequent monitoring for adverse events, outcomes, donor-specific antibodies, and renal function was performed, as were renal biopsies. Immunosuppression after transplantation consisted of tacrolimus, mycophenolate mofetil, and glucocorticoids. Patients in the U.S. study also received intravenous immune globulin and rituximab after transplantation to prevent antibody rebound. RESULTS: Recipients in the U.S. study had a significantly longer cold ischemia time (the time elapsed between procurement of the organ and transplantation), a significantly higher rate of delayed graft function, and significantly higher levels of class I donor-specific antibodies than those in the Swedish study. A total of 38 serious adverse events occurred in 15 patients (5 events were adjudicated as being possibly related to IdeS). At transplantation, total IgG and HLA antibodies were eliminated. A total of 24 of 25 patients had perfusion of allografts after transplantation. Antibody-mediated rejection occurred in 10 patients (7 patients in the U.S. study and 3 in the Swedish study) at 2 weeks to 5 months after transplantation; all these patients had a response to treatment. One graft loss, mediated by non-HLA IgM and IgA antibodies, occurred. CONCLUSIONS: IdeS reduced or eliminated donor-specific antibodies and permitted HLA-incompatible transplantation in 24 of 25 patients. (Funded by Hansa Medical; ClinicalTrials.gov numbers, NCT02224820 , NCT02426684 , and NCT02475551 .).

High Posttransplant Cancer Incidence in Renal Transplanted Patients With Pretransplant Cancer.

BACKGROUND: Patients with previous cancer have increasingly been accepted for renal transplantation. Posttransplant cancer risk and survival rates of these patients are unknown. Our objective was to assess the risk of posttransplant cancer in this patient group. METHODS: In this retrospective, nested case-control study, we assessed the outcome of all (n = 95) renal transplanted patients with pretransplant cancer diagnoses in the Uppsala-Örebro region, Sweden. The control group was obtained from the Collaborative Transplant Study registry and included European patients without pretransplant cancer. The other control group comprised the entire renal transplanted population in Uppsala. Development of recurrent cancer, de novo cancer, and patient survival were determined. RESULTS: Patients with pretransplant cancer showed higher incidence of posttransplant cancers and shorter survival compared with the control groups (P < 0.001). No obvious pattern in malignant diagnoses was observed. Death-censored graft survival was unaffected. CONCLUSIONS: Despite previously adequate cancer treatments and favorable prognoses, almost half of the patients experienced a posttransplant cancer. These observations do not justify abstaining from transplanting all patients with previous malignancies, because more than 50% of the patients survive 10 years posttransplantation. A careful oncological surveillance pretransplant as well as posttransplant is recommended.

Association between HLA-A1 and -A2 types and Epstein-Barr virus status of post-transplant lymphoproliferative disorder.

The susceptibility to Epstein-Barr virus (EBV)-related post-transplant lymphoproliferative disorder (PTLD) may be affected by the human leukocyte antigen (HLA) type. We investigated HLA-A and HLA-B allele frequencies, focusing on HLA-A1 and -A2, in a population-based case series of EBV + (n = 60) and EBV- (n = 44) PTLD after solid organ transplantation. The proportion of EBV + PTLD was highest in HLA-A1 homozygotes (100%), lower in carriers of HLA-A1/AX (79%), HLA-A1/A2 (55%), HLA-A2/AX (54%), and lowest in HLA-A2 homozygotes (37%). HLA-A1 type was overrepresented (22% versus 7%, p = 0.05) and HLA-A2 type underrepresented (57% versus 80%, p = 0.01) in patients with EBV + compared with EBV - PTLD. EBV + PTLD in HLA-A1 carriers developed almost exclusively in already EBV-seropositive individuals. EBV status of PTLD was not related to any other HLA-A or HLA-B type. Our findings suggest that HLA-A1 carriers may have an increased risk of EBV + PTLD due to a decreased ability to control the latent EBV infection.

Malignancies in transplanted patients: Multidisciplinary evaluation and switch to mTOR inhibitors after kidney transplantation - experiences from a prospective, clinical, observational study.

Background Solid organ transplant recipients are at increased risk of developing malignancies. The objective of this prospective, observational, one-armed study was to study the feasibility to add a mammalian target of rapamycin (mTOR) inhibitor to the immunosuppressive regimen in transplanted patients with post-transplant malignancies. During the trial the need to improve identification of post-transplant malignancies and to reassure adequate oncological treatment of these patients became evident. Multidisciplinary team (MDT) evaluation of oncological and immunosuppressive treatments was implemented for all patients with malignancies after renal or combined renal and pancreas transplantation because of the trial. Material and methods At Uppsala University Hospital, Sweden, a MDT consisting of transplant surgeons, nephrologists, oncologists and dermatologists evaluated 120 renal or combined renal and pancreas-transplanted recipients diagnosed with malignancies from September 2006 to July 2012. To identify all malignancies, the population was linked to the Regional Tumor Registry (RTR). We recorded to which extent a switch to mTOR inhibitors was possible and how often the originally planned oncological managements were adjusted. All patients were followed for three years. (ClinicalTrials.gov: NCT02241564). Results In 76 of 120 patients (63%) a switch to mTOR inhibitors was possible. Immunosuppression was interrupted in seven patients (6%), reduced in three patients (2%) and remained unchanged in 34 of 120 patients (28%). Identification of post-transplant malignancies increased significantly after linkage to RTR (p = 0.015). The initially recommended oncological treatment was adjusted in 23 of 44 patients (52%) with solid or hematological malignancies; 36 of these patients (82%) were treated according to national guidelines. Conclusion In two thirds of the patients the immunosuppressive treatment could be changed to an mTOR inhibitor with anti-tumor effects in transplanted patients with post-transplant malignancies. The use of regional tumor registers considerably improved the identification of patients with post-transplant malignancies indicating that post-transplant malignancies might be timely underreported in transplant registers.

A population-based study of 135 lymphomas after solid organ transplantation: The role of Epstein-Barr virus, hepatitis C and diffuse large B-cell lymphoma subtype in clinical presentation and survival.

BACKGROUND: Epstein-Barr virus (EBV) plays a major role in the development of post-transplant lymphoproliferative disorder (PTLD), but there is an increasing awareness of EBV-negative PTLD. The clinical presentation of EBV-negative PTLD has not been as well characterised as EBV-positive cases. Further, there is limited knowledge on the clinical importance of diffuse large B-cell lymphoma (DLBCL) cell of origin subtype post-transplant. MATERIALS AND METHODS: We studied the role of EBV, hepatitis C (HCV) and DLBCL subtype in clinical presentation and survival in 135 post-transplant lymphomas diagnosed 1980-2006 in a population-based cohort of 10 010 Swedish solid organ transplant recipients. The lymphomas were re-evaluated according to WHO 2008, examined for EBV, and clinical data were collected from medical records. RESULTS: Lymphoma incidence rate was 159/100 000 person-years and is also reported by lymphoma subtype. EBV-negative lymphomas constituted 48% and were associated with HCV infection (p = 0.02), bone marrow involvement (p < 0.001), and T-cell phenotype (p = 0.002). Among DLBCL, 78% were of non-germinal centre subtype, which was associated with EBV-positivity (69%, p = 0.001), early occurrence (p = 0.03), heart/liver/lung/pancreas recipients (p = 0.02), anti-T-cell globulin (p = 0.001), and tacrolimus treatment (p = 0.02). DLBCL subtypes had similar overall survival. Five-year overall survival was 42% in all treated patients. Independent poor prognostic factors were older age, B symptoms, ECOG 2-4, kidney/pancreas/heart recipients, T-cell lymphoma, and HCV-infection. CONCLUSIONS: With long follow-up, a large part of PTLD is EBV-negative, due to a high proportion of T-cell lymphomas and low of polymorphic PTLD. EBV-negative PTLD have a different clinical presentation. HCV may play an aetiological role in late-onset PTLD and was revealed as a new prognostic factor for inferior survival that needs to be confirmed in larger studies. The heavier immunosuppression in non-kidney transplantations seems to play a role in the development of non-germinal centre DLBCL. DLBCL cell of origin subtype lacks prognostic importance in the transplant setting.

Islet engraftment and revascularization in clinical and experimental transplantation.

Proper revascularization after transplantation is assumed to be crucial for appropriate islet graft function. We developed a novel noninvasive imaging method, based on adenoviral transduction of islets with a hypoxia responsive reporter gene, for continuous in vivo monitoring of hypoxia in islet grafts in a mouse model. In addition, morphological data were obtained from a deceased patient previously subject to intraportal transplantation. We detected only transient hypoxia in a minority of the animals transplanted. Importantly, a clear response to hypoxia was observed in vitro after removal of the islet grafts on day 28 after transplantation. Also, the morphological data from the deceased patient demonstrated an extensive revascularization of the transplanted islets. In fact, no differences could be seen between native islets, in pancreas biopsies taken prior to islet isolation, and transplanted islets regarding the number, distribution, and shape of the blood vessels. However, fewer small islets (diameter <39 µm) were found in the liver compared to those found in native pancreases. Notably, an absolute majority of the transplanted islets were found remaining within the venous lumen, in direct contact with the vessel wall. In conclusion, the results presented show less pronounced islet graft hypoxia after subcapsular transplantation than previously reported using more invasive methods. Also, formation of an extensive intraislet capillary network, similar to that seen in native islets in the pancreas, was seen after clinical islet transplantation.

No association between infections, HLA type and other transplant-related factors and risk of cutaneous squamous cell carcinoma in solid organ transplant recipients.

Recipients of solid organ transplants are at a markedly increased risk of cutaneous squamous cell carcinoma (SCC). We investigated potential associations between post-transplant infections, HLA type, and other transplant-related factors and risk of SCC, taking immuno-suppressive treatment into account. A population-based case-control study was conducted. All patients who developed SCC during follow-up (1970-1997) were eligible as cases (n = 207). Controls (n = 189) were individually matched to the cases on age and calendar period of transplantation. Detailed exposure information was collected through an extensive, blinded review of medical records. Odds ratios were computed with conditional logistic regression. There were no significant associations with any infectious agents, or with number and timing of infections, specific HLA-type, donor characteristics, or other transplant characteristics and risk of post-transplant SCC. These results suggest that risk of post-transplant SCC is neither closely related to specific post-transplant infectious disorders, nor to the infectious load or specific HLA types.

Isolation, expansion and functional assessment of CD4+CD25+FoxP3+ regulatory T cells and Tr1 cells from uremic patients awaiting kidney transplantation.

BACKGROUND: The immunosuppressive properties of regulatory T cells have emerged as an attractive tool for the development of immunotherapies in various disease contexts, e.g. to treat transplantation induced immune reactions. This paper focuses on the process of obtaining and functionally characterizing CD4+CD25+FoxP3+ regulatory T cells and Tr1 cells from uremic patients awaiting kidney transplantation. METHODS: From October 2010 to March 2011 uremic patients awaiting living donor kidney transplantation, and their corresponding kidney donors, were enrolled in the study. A total of seven pairs were included. Isolation of CD4+CD25+FoxP3+ regulatory T cells was performed by magnetic activated cell sorting of peripheral blood mononuclear cells obtained from the uremic patients. Donor specific Tr1 cells were differentiated by repetitive stimulation of immature CD4+ T cells with immature dendritic cells, with the T cells coming from the future kidney recipients and the dendritic cells from the corresponding kidney donors. Cells were then expanded and functionally characterized by the one-way mixed leukocyte reaction and assessment of IL-10 production. Phenotypic analysis was performed by flow cytometry. RESULTS: The fraction of CD4+CD25+FoxP3+ regulatory T cells after expansion varied from 39.1 to 50.4% and the cells retained their ability to substantially suppress the mixed leukocyte reaction in all but one patient (3.8-19.2% of the baseline stimulated leukocyte activity, p<0.05). Tr1 cells were successfully differentiated from all but one patient and produced high levels of IL-10 when stimulated with immature dendritic cells (1,275-11,038% of the baseline IL-10 secretion, p<0.05). CONCLUSION: It is practically feasible to obtain and subsequently expand CD4+CD25+FoxP3+ regulatory T cells and Tr1 cells from uremic patients without loss of function as assessed by in vitro analyses. This forms a base for adoptive regulatory T cell therapy in the setting of living donor kidney transplantation.

Further evidence for amyloid deposition in clinical pancreatic islet grafts.

BACKGROUND: The reasons for the long-term complete or partial loss of islet graft function are unknown, but there are obviously other reasons than just pure allogeneic graft rejection. Earlier studies have shown that deposition of islet amyloid polypeptide amyloid in transplanted islets may indicate a mechanism for loss of ß cells. MATERIALS AND METHODS: Sections from liver material from four deceased islet-bearing recipients have been scrutinized for the presence of amyloid. Clinical data and certain aspects of the islet graft pathology of these patients have been published previously. RESULT: With this extended histological analysis, we demonstrate the occurrence of amyloid deposits in islets transplanted into the liver in three of four patients with type 1 diabetes. CONCLUSION: The finding adds evidence to the assumption that aggregation of islet amyloid polypeptide might be an important cause of progressing ß-cell dysfunction in clinically transplanted islets.

Immunosuppressive treatment after solid organ transplantation and risk of post-transplant cutaneous squamous cell carcinoma.

BACKGROUND: The risk of cutaneous squamous cell carcinoma (CSCC) is found to be substantially increased after organ transplantation. The association with specific immunosuppressive regimens has been previously investigated, but results are not concordant. We aimed to clarify the relationship between separate immunosuppressive drugs, drug load, timing and risk of post-transplant CSCC. METHODS: A population-based nested case-control study was performed in the Swedish organ transplantation cohort (n = 5931). All patients who developed CSCC during the follow-up (1970-97) were eligible as cases (n = 207). Controls (n = 189) were randomly selected from the cohort and individually matched to the cases on follow-up time, age at and calendar period of transplantation. Exposure information was collected through extensive and standardized review of medical records. RESULTS: The median time to CSCC was 6.7 years. Post-transplant azathioprine (Aza) treatment considerably increased the risk of CSCC during all time periods analysed, and the risk augmented with increasing dose and duration. Patients who after the entire follow-up period had received a high accumulated dose of Aza had an 8.8-fold increased risk of CSCC in multivariate analysis (P < 0.0001), compared to patients never treated with Aza. Additionally, a high accumulated dose of corticosteroids during the same period conferred a 3.9-fold elevated risk of CSCC (P = 0.09), compared to the lowest accumulated dose of corticosteroids. Cyclosporine treatment was not associated with the risk of CSCC post-transplantation. CONCLUSIONS: This study provides evidence that Aza treatment, but not cyclosporine treatment, is strongly associated with post-transplant CSCC risk. The results suggest that the risk of CSCC after organ transplantation is not only an effect of the immunosuppressive load per se.

A randomized, doubleblind, placebo-controlled, study of single-dose rituximab as induction in renal transplantation.

UNLABELLED: We performed a prospective, double blind, randomized, placebo-controlled multicenter study on the efficacy and safety of rituximab as induction therapy, together with tacrolimus, mycophenolate mofetil, and steroids. The primary endpoint was defined as acute rejection, graft loss, or death during the first 6 months. Secondary endpoints were creatinine clearance, incidence of infections, and incidence of rituximab-related adverse event. RESULTS: We enrolled 140 patients (44 living donor and 96 deceased donor), and of those, 68 rituximab and 68 placebo patients fulfilled the study. In all the patients receiving rituximab, there was a complete depletion of CD19/CD20 cells, whereas there was no change in the number of CD19/CD20 cells in the placebo group. There were 10 treatment failures in the rituximab group versus 14 in the placebo group (P=0.348). There were eight rejection episodes in the rituximab group versus 12 in the placebo group (P=0.317) Creatinine clearance was 66+/-22 mL/min in the study group and 67+/-23 mL/min in the placebo group. There was no difference in the number of bacterial infections, cytomegalovirus infections, and BK virus infections or fungal infections. CONCLUSION: We performed a placebo-controlled study of rituximab induction in renal transplantation. There was a tendency toward fewer and milder rejections during the first 6 months in the rituximab group. Although induction with one dose of rituximab induced a complete depletion B cells, there was no increase in the incidence of infectious complications or leukopenia and it seems safe, therefore, to conduct further studies on the use of rituximab in transplantation.

No beneficial effect of two-layer storage compared with UW-storage on human islet isolation and transplantation.

BACKGROUND: Shipment of pancreata between distant centers is frequently associated with prolonged cold ischemia time (CIT) that leads to poorer outcomes for islet transplantation. Clinical pilot trials have indicated that oxygenation of explanted human pancreata utilizing the two-layer method (TLM) allows the use of marginal donor pancreata for islet transplantation. The present study aimed to clarify whether TLM enhances the ischemic tolerance of human pancreata. METHODS: We analyzed retrospectively the outcome of 200 human islet isolations performed after TLM preservation or storage in University of Wisconsin solution (UWS). RESULTS: Donor characteristics and digestion parameters did not vary significantly between TLM-preserved and UWS-stored pancreata. No differences were observed between experimental groups with regard to islet yield, purity, or dynamic glucose stimulation index after either short or prolonged CIT. However, CIT and stimulation index were negatively correlated in each experimental group. The isolation outcome in donors aged > or =60 years was not increased after TLM preservation when compared to UWS storage. No effect was observed regarding islet posttransplant function in recipients with established kidney grafts. CONCLUSIONS: The present study suggests that the ischemic tolerance of human pancreata cannot be extended by TLM preservation. In addition, TLM does not seem to improve the isolation outcome for pancreata from elderly donors.