Long‐term outcome of belatacept therapy in de novo kidney transplant recipients – a case‐match analysis

While belatacept has shown favorable short‐ and midterm results in kidney transplant recipients, only projections exist regarding its potential impact on long‐term outcome. Therefore, we performed a retrospective case‐match analysis of the 14 belatacept patients originally enrolled in the phase II multicenter trial at our center. Fifty six cyclosporine (CyA)‐treated patients were matched according to age at transplantation, first/retransplant, and donor type. Ten years after kidney transplantation, kidney function remained superior in belatacept‐treated patients compared with the CyA control group. Moreover, none of the belatacept‐treated patients had donor‐specific antibodies ≥10 years post‐transplantation compared with 38.5% of tested CyA‐treated subject (0/10 vs. 5/13; P = 0.045). Notably, however, patient and graft survival was virtually identical in both groups (71.4% vs. 71.3%; P = 0.976). In the present single‐center study population, patients treated with belatacept demonstrated a patient and graft survival at 10 years post‐transplant which was comparable to that of similarly selected CNI‐treated patients. Larger studies with sufficient statistical power are necessary to definitively determine long‐term graft survival with belatacept.     

Eurotransplant donor‐risk‐index and recipient factors: influence on long‐term outcome after liver transplantation – A large single‐center experience

The organ shortage has led to increased use of marginal organs. The Eurotransplant Donor‐Risk‐Index (ET‐DRI) was established to estimate outcome after Liver Transplantation (LT). Currently, data on impact of ET‐DRI on long‐term outcome for different indications and recipient conditions are missing. Retrospective, single‐center analysis of long‐term graft survival (GS) of 1767 adult primary LTs according to indication, labMELDcategory (1: ≤18; 2: >18–25; 3: >25–35; 4: >35), and ET‐DRI. Mean ET‐DRI in our cohort was 1.63 (±0.43). One‐, 10, and 15‐yr GS was 83.5%, 63.3%, and 54.8%. Long‐term GS was significantly influenced by ET‐DRI. Accordingly, four ET‐DRI categories were defined and analyzed with respect to underlying disease. Significant impact of these categories was observed for: Alcohol, cholestatic/autoimmune diseases (CD/AIH), and HCV, but not for HCC, HBV, cryptogenic cirrhosis, and acute liver failure. labMELD categories showed no significant influence on graft, but on patient survival. Matching ET‐DRI categories with labMELD revealed significant differences in long‐term GS for labMELDcategories 1, 2, and 3, but not 4. In multivariate analysis, HCV combined with ET‐DRI > 2 and labMELDcategory 3 combined with ET‐DRI > 2 emerged as negative predictors. To achieve excellent long‐term graft survival, higher risk organs (ET‐DRI > 1.4) should be used restrictively for patients with CD/AIH or HCV. Organs with ET‐DRI > 2 should be avoided in patients with a labMELD of >25–35.     

Progressive improvement in short‐, medium‐ and long‐term graft survival in kidney transplantation patients in Ireland – a retrospective study

It is often quoted that while short‐term graft survival in kidney transplantation has improved in recent years, it has not translated into a commensurate improvement in long‐term graft survival. We considered whether this was true of the entire experience of the national kidney transplant program in Ireland. A retrospective analysis of the National Kidney Transplant Service (NKTS) database was undertaken to investigate patient and graft survival for all adult first deceased donor kidney transplant recipients in Ireland, 1971–2015. Three thousand two hundred and sixty recipients were included in this study. Kaplan–Meier methods were used to estimate survival at each time period post transplant for the various eras of transplantation. Uncensored graft survival has improved over the course of the program in Ireland at various time points despite risk factors for graft failure progressively increasing over successive eras. For example the graft survival at 15 years post transplant has increased from 10% in 1971–1975 to 45% by 1996–2000. Ireland has experienced a progressive improvement in long‐term graft survival following kidney transplantation. Whether these trends are attributable to biological or nonbiological factors is unclear but likely involves a combination of both.     

Prolonged survival of pig islets xenograft by adenovirus‐mediated expression of either the membrane‐bound human FasL or the human decoy Fas antigen gene

Abstract: Background: Pig islets are considered an attractive alternative treatment for patients with Type 1 diabetes. However, pig islet xenografts, transplanted into non‐human primates, are directly rejected by cell‐mediated processes. We have previously reported that cell‐mediated xenograft‐rejections, and especially human CD8⁺ cytotoxic T lymphocytes (CTL)‐mediated cytotoxicity, are highly detrimental to pig xenograft cells. Moreover, we have explored novel strategies for the prevention of CTL killing by overexpression of either human decoy Fas antigen or membrane‐bound human FasL in pig endothelial cells. In this study, we assessed the cytoprotective effects of these molecules for pig islets both in vitro and in vivo. Materials and methods: Pig islets were freshly isolated by modified Ricordi’s methods. Subsequently, these islets were transfected with an adenoviral expression vector containing the DNA fragments of either membrane‐bound human FasL or human decoy Fas. Transfected islets were transplanted into preimmunized diabetic rats under the kidney capsule. Control pig islets (i.e., MOCK), which were transfected with an adenoviral expression vector containing only the enhanced green fluorescent protein gene, were also transplanted. Results: Efficiency of adenoviral expressions of these molecules in pig islets was approximately 80% at a multiplicity of infection of 100. In an in vitro assay, approximately 80% suppression of cytotoxicity was observed in membrane‐bound human FasL‐expressing pig islets and 60% inhibition of CTL killing was displayed in decoy Fas expression pig islets. In an in vivo transplant model, prolonged survival of pig islets xenografts, expressing either membrane‐bound human FasL or human decoy Fas genes, was elicited in comparison with that of control islets xenografts. Conclusion: The extracellular remodeling of either death receptor or death ligand genes by adenoviral expression was effective for the prevention of CTL‐mediated xenocytotoxicity in pig islets.     

A case of esophageal adenocarcinoma on long‐term rapamycin monotherapy

Cancer in transplant recipients represents a therapeutic challenge even when the patient is already under mTOR inhibitors. A 78‐year‐old man received a deceased donor kidney transplant in 1993. After 6 months, he developed a multifocal cutaneous and nonvisceral Kaposi's Sarcoma while on cyclosporine immunosuppressant therapy. The patient was converted to sirolimus monotherapy in 2001 with subsequent complete recovery within 2 years. In 2007, the patient was diagnosed with an esophageal adenocarcinoma stage IIA. An esophagectomy was performed without requirement of further treatment. He has continued on sirolimus monotherapy ever since, with no other incidents and no recurrences of either tumor. In this report, we describe an interesting case of a second cancer while on immunosuppressive therapy with anticancer activity. Moreover, the present knowledge of the matter is discussed.     

Development of a chemiluminescence immunoassay using recombinant non‐structural epitope‐based proteins to accurately differentiate foot‐and‐mouth disease virus‐infected and vaccinated bovines

The contamination of inactivated vaccine with non‐structural proteins (NSP s) leads to a high false‐positive rate, which is a substantial barrier to accurately differentiate foot‐and‐mouth disease virus (FMDV )‐infected animals from vaccinated animals. To address this problem, a new chemiluminescence immunoassay (CLIA ) method was developed to detect antibodies targeting the two recombinant epitope‐based proteins located in 3A and 3B. The 3Aepitp‐3Bepitp CLIA exhibited a diagnostic sensitivity of 94.0% and a diagnostic specificity of 97.5% for the detection of serum samples (naïve bovines, n  = 52, vaccinated bovines, n  = 422, infected bovines, n  = 116) from animals with known status. The CLIA method also had a concordance rate of 88.1% with the PrioCHECK FMDV NSP ELISA based on the detection of 270 serum samples from the field. Importantly, the 3Aepitp‐3Bepitp CLIA produced no false‐positives when used to detect FMDV in samples from bovines that had been vaccinated up to five times, and it was demonstrated a low false‐positive rate when the bovines had been vaccinated up to ten (2.15%) and fifteen times (5.93%). Therefore, the 3Aepitp‐3Bepitp CLIA detects FMDV in samples from frequently vaccinated bovines with high accuracy and represents an alternative method to differentiate FMDV ‐infected and vaccinated bovines.     

The survival effect of E‐cadherin and catenins in colorectal carcinomas

Aim The E‐cadherin/catenin complex plays an important role in epithelial tissue architecture. Decreased expression of cell adhesion molecules (E‐cadherin, α‐, β‐ and γ‐catenin) have been reported to correlate with invasive behaviour. The aim of this study was to investigate the relation between the expression of adhesion molecules and clinicopathological characteristics and survival in colorectal carcinoma. Method The expression of adhesion molecules were studied by immunohistochemistry in 138 colorectal carcinomas. Results The mean age of the patients was 65 years (range: 21–89 years). In primary carcinomas, a reduction in membranous expression of E‐cadherin, α‐catenin, β‐catenin, γ‐catenin was demonstrated (70%, 68%, 73%, 77%, respectively). Nuclear expression of β‐catenin was found in eight (5%) patients. Decreased membranous β‐ and γ‐catenin expression significantly correlated with tumour differentiation (P = 0.013, P = 0.03, respectively). There was a significant association between advanced stage of the tumour and decreased membranous α‐catenin expression (P = 0.012). Decreased E‐cadherin and β‐catenin membranous expression correlated with short survival following curative resection of the primary tumour (P = 0.04, P = 0.03, respectively). Conclusion The decreased membranous expression of E‐cadherin and β‐catenin and increased cytoplasmic expression of β‐catenin might be used as a prognostic marker to monitor patients with colorectal cancer.     

The influence of body mass index on the long-term survival of patients with renal cell carcinoma after tumour nephrectomy

OBJECTIVE

To assess whether under‐ or overweight at the time of surgery has any effect on the survival of the patients with renal cell carcinoma (RCC), as obesity increases the risk of developing RCC.

PATIENTS AND METHODS

We prospectively evaluated 780 patients who had nephrectomy for RCC between 1990 and 2005. We used uni‐ and multivariate Cox proportional hazards models to assess the effect of body mass index (BMI), tumour stage, Fuhrman grade, age, sex, histological type and performance status on cancer‐specific survival (CSS). Patients were grouped according to BMI (in kg/m²), as underweight (<18.5), normal (18.5–<25), overweight (25–<30) and obese (≥30).

RESULTS

The median (range) follow‐up was 5.3 (0.5–15.4) years, the patients being followed until June 2006; 254 patients died during the follow‐up. Multivariate analyses of all patients showed that tumour stage, Fuhrman grade, Karnofsky performance status, age, sex and BMI were independent prognostic factors for CSS. While underweight patients had a significantly worse prognosis than those of normal weight, overweight or obese patients had a similar outcome to that of patients of normal weight. In a subgroup analyses including patients with localized RCC only, there was a strong tendency to less aggressive disease in the overweight group (P = 0.081).

CONCLUSIONS

Being underweight is an unfavourable and new risk factor for CSS in patients with RCC treated by nephrectomy. Although not significant, there seems to be a limited favourable prognostic effect of overweight on CSS in patients with localized RCC.     

Enhanced effect of human mesenchymal stem cells expressing human TNF‐αR‐Fc and HO‐1 gene on porcine islet xenotransplantation in humanized mice

Background

Porcine islet xenotransplantation is considered an attractive alternative treatment for type 1 diabetes mellitus. However, it is largely limited because of initial rejection due to Instant Blood‐Mediated Inflammatory Reaction (IBMIR), oxidative stress, and inflammatory responses. Recently, soluble tumor necrosis factor‐ɑ receptor type I (sTNF‐αR) and heme oxygenase (HO)‐1 genes (HO‐1/sTNF‐αR) have been shown to improve the viability and functionality of porcine islets after transplantation.

Methods

In this study, genetically modified mesenchymal stem cells (MSCs) expressing the HO‐1/sTNF‐αR genes (HO‐1/sTNF‐αR‐MSC) were developed using an adenoviral system, and porcine islet viability and function were confirmed by in vitro tests such as GSIS, AO/PI, and the ADP/ATP ratio after coculturing with HO‐1/sTNF‐αR‐MSCs. Subsequently, isolated porcine islets were transplanted underneath the kidney capsule of diabetic humanized mice without MSCs, with MSCs or with HO‐1/sTNF‐αR‐MSCs.

Results

According to the results, the HO‐1/sTNF‐αR‐MSC‐treated group exhibited improved survival of porcine islets and could reverse hyperglycemia more than porcine islets not treated with MSCs or islets cotransplanted with MSCs. Moreover, the HO‐1/sTNF‐αR‐MSC group maintained its morphological characteristics and the insulin secretion pattern of transplanted porcine islets similar to endogenous islets in immunocompetent humanized mice.

Conclusions

Our results suggest that HO‐1/sTNF‐αR‐MSCs are efficient tools for porcine islet xenotransplantation, and this study may provide basic information for pre‐clinical animal models and future clinical trials of porcine islet xenotransplantation.     

Influence of age at ileoanal pouch creation on long‐term changes in functional outcomes

Aim We reviewed the functional results and quality of life (QOL) of patients who had had an ileoanal pouch (IPAA) for at least 15 years. Method Retrospective analysis was undertaken of data accrued prospectively into a pouch database since 1983. Patients who had retained an IPAA for at least 15 years were identified. Trends in IPAA function and QOL of the patients were determined over a time‐period of 15 years after formation of the IPAA. Data were compared for patients who were < 35, 35–55 and > 55 years of age when the IPAA was formed. Results Three hundred and ninety‐six of a total of 3276 patients in the database (53% men, median age 36 years and median follow‐up 17.1 years) underwent IPAA with at least 15 years of follow‐up. The final pathology was ulcerative colitis in 78%; 66.4% of patients had a restorative proctocolectomy, 91.4% underwent temporary diversion, 59% had a J‐pouch configuration and 63.1% a stapled anastomosis. The frequency of bowel movements remained the same over the follow‐up period. There was an increase in the incidence of incontinence and urgency after 15 years with no significant change in dietary, social, work and sexual restrictions during follow‐up. Patients in all three age groups experienced deterioration in pouch function at 15 years of follow up compared with the function at 5 years. The QOL of the patients remained high and stable. Conclusion There is a deterioration of pouch function after 15 years, irrespective of the age of the patient when the IPAA was formed. Despite this, QOL appears to be high for all patients who retain their pouch.     

Islet Transplantation in Type 1 Diabetics Using an Immunosuppressive Protocol Based on the Anti‐LFA‐1 Antibody Efalizumab

The applicability of islet transplantation as treatment for type 1 diabetes is limited by renal and islet toxicities of currently available immunosuppressants. We describe a novel immunosuppressive regimen using the antileukocyte functional antigen‐1 antibody efalizumab which permits long‐term islet allograft survival while reducing the need for corticosteroids and calcineurin inhibitors (CNI). Eight patients with type 1 diabetes and hypoglycemic unawareness received intraportal allogeneic islet transplants. Immunosuppression consisted of antithymocyte globulin induction followed by maintenance with efalizumab and sirolimus or mycophenolate. When efalizumab was withdrawn from the market in mid 2009, all patients were transitioned to regimens consisting of mycophenolate and sirolimus or mycophenolate and tacrolimus. All patients achieved insulin independence and four out of eight patients became independent after single‐islet transplants. Insulin independent patients had no further hypoglycemic events, hemoglobin A1c levels decreased and renal function remained stable. Efalizumab was well tolerated and no serious adverse events were encountered. Although long‐term follow‐up is limited by discontinuation of efalizumab and transition to conventional imunnosuppression (including CNI in four cases), these results demonstrate that insulin independence after islet transplantation can be achieved with a CNI and steroid‐free regimen. Such an approach may minimize renal and islet toxicity and thus further improve long‐term islet allograft survival.     

The usefulness and limitations of the diabetic macaque model in evaluating long‐term porcine islet xenograft survival

Abstract: Background: Various groups have reported prolonged diabetes reversal and graft function after porcine islet transplantation into diabetic macaques using different experimental designs (macaque source, islet source, type of immunosuppression): subsequently, the International Xenotransplantation Association has published recommendations for entering a clinical trial. Our experiments showed limitations that affected consistent achievement of long‐term survival. We aimed to identify these limitations and underlying causes to emphasize the translational value of this highly relevant type 1 diabetic macaque model. Methods: We reviewed data from our institution and literature data on long‐term porcine islet xenograft survival in the diabetic macaque model, especially focusing on aspects of incomplete diabetes reversal relative to macaque normal values. This phenomenon was compared with diabetes reversal in an allo‐islet transplant model in macaques and with chronic insulin treatment of diabetic macaques, all with 180‐day follow‐up. This comparison enabled to identify potential model limitations and underlying causative factors. Results: Especially in the xenograft model, the achievement of long‐term graft survival revealed limitations including chronic, mild hyperglycemia and absence of body weight (BW) gain or even progressive BW loss. Metabolic incompatibilities in glycemic control (i.e., insulin kinetics) between the pig and macaque species underlie chronic, mild hyperglycemia. This phenomenon might not bear relevance for the pig‐to‐human species combination because the glycemic control in pigs and humans is similar and differs from that in nonhuman primates (NHP). Weight loss could be related to changes in the gastrointestinal tract related with local high exposure to orally administered immunosuppressants; these must be given at higher dose levels because of low bioavailability in macaques to achieve systemic exposure at therapeutic levels. This is aggravated by insufficient graft insulin production in proportion to the needs of macaques: this model limitation has no translational value to the pig‐to‐human setting. Nutritional deficits can result in incorrect interpretation of blood glucose levels and C‐peptide levels regarding graft function. Likewise, nutritional status alters physiologic responses, influencing susceptibility to infectious and noninfectious complications. Conclusion: The model‐induced confounding described interferes with accurate interpretation of safety and efficacy studies, which affects the translational value of pig‐to‐NHP islet cell transplant studies to the pig‐to‐human transplant condition.