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1.
Transpl Int ; 37: 12750, 2024.
Article in English | MEDLINE | ID: mdl-38881801

ABSTRACT

Patients with end-stage heart disease who undergo a heart transplant frequently have simultaneous kidney insufficiency, therefore simultaneous heart and kidney transplantation is an option and it is necessary to understand its characteristics and long-term variables. The recipient characteristics and operative and long-term variables were assessed in a meta-analysis. A total of 781 studies were screened, and 33 were thoroughly reviewed. 15 retrospective cohort studies and 376 patients were included. The recipient's mean age was 51.1 years (95% CI 48.52-53.67) and 84% (95% CI 80-87) were male. 71% (95% CI 59-83) of the recipients were dialysis dependent. The most common indication was ischemic cardiomyopathy [47% (95% CI 41-53)] and cardiorenal syndrome [22% (95% CI 9-35)]. Also, 33% (95% CI 20-46) of the patients presented with delayed graft function. During the mean follow-up period of 67.49 months (95% CI 45.64-89.33), simultaneous rejection episodes of both organ allografts were described in 5 cases only. Overall survival was 95% (95% CI 88-100) at 30 days, 81% (95% CI 76-86) at 1 year, 79% (95% CI 71-87) at 3, and 71% (95% CI 59-83) at 5 years. Simultaneous heart and kidney transplantation is an important option for concurrent cardiac and renal dysfunction and has acceptable rejection and survival rates.


Subject(s)
Graft Rejection , Graft Survival , Heart Transplantation , Kidney Transplantation , Humans , Male , Middle Aged , Female , Cardio-Renal Syndrome/surgery , Delayed Graft Function , Retrospective Studies , Kidney Failure, Chronic/surgery , Kidney Failure, Chronic/complications , Heart Failure/surgery , Heart Failure/mortality , Treatment Outcome
2.
Pediatr Nephrol ; 38(1): 145-159, 2023 01.
Article in English | MEDLINE | ID: mdl-35507150

ABSTRACT

BACKGROUND: Primary FSGS manifests with nephrotic syndrome and may recur following KT. Failure to respond to conventional therapy after recurrence results in poor outcomes. Evaluation of podocyte B7-1 expression and treatment with abatacept (a B7-1 antagonist) has shown promise but remains controversial. METHODS: From 2012 to 2020, twelve patients developed post-KT FSGS with nephrotic range proteinuria, failed conventional therapy, and were treated with abatacept. Nine/twelve (< 21 years old) experienced recurrent FSGS; three adults developed de novo FSGS, occurring from immediately, up to 8 years after KT. KT biopsies were stained for B7-1. RESULTS: Nine KTRs (75%) responded to abatacept. Seven of nine KTRs were B7-1 positive and responded with improvement/resolution of proteinuria. Two patients with rFSGS without biopsies resolved proteinuria after abatacept. Pre-treatment UPCR was 27.0 ± 20.4 (median 13, range 8-56); follow-up UPCR was 0.8 ± 1.3 (median 0.2, range 0.07-3.9, p < 0.004). Two patients who were B7-1 negative on multiple KT biopsies did not respond to abatacept and lost graft function. One patient developed proteinuria while receiving belatacept, stained B7-1 positive, but did not respond to abatacept. CONCLUSIONS: Podocyte B7-1 staining in biopsies of KTRs with post-transplant FSGS identifies a subset of patients who may benefit from abatacept. A higher resolution version of the Graphical abstract is available as Supplementary information.


Subject(s)
Glomerulosclerosis, Focal Segmental , Podocytes , Adult , Child , Humans , Young Adult , Glomerulosclerosis, Focal Segmental/drug therapy , Glomerulosclerosis, Focal Segmental/pathology , Abatacept/therapeutic use , Proteinuria/drug therapy , Proteinuria/etiology , Podocytes/pathology , Staining and Labeling , Recurrence
3.
Diabetologia ; 64(7): 1626-1641, 2021 07.
Article in English | MEDLINE | ID: mdl-33912981

ABSTRACT

AIMS/HYPOTHESIS: We and others previously reported the presence of tertiary lymphoid organs (TLOs) in the pancreas of NOD mice, where they play a role in the development of type 1 diabetes. Our aims here are to investigate whether TLOs are present in the pancreas of individuals with type 1 diabetes and to characterise their distinctive features, in comparison with TLOs present in NOD mouse pancreases, in order to interpret their functional significance. METHODS: Using immunofluorescence confocal microscopy, we examined the extracellular matrix (ECM) and cellular constituents of pancreatic TLOs from individuals with ongoing islet autoimmunity in three distinct clinical settings of type 1 diabetes: at risk of diabetes; at/after diagnosis; and in the transplanted pancreas with recurrent diabetes. Comparisons were made with TLOs from 14-week-old NOD mice, which contain islets exhibiting mild to heavy leucocyte infiltration. We determined the frequency of the TLOs in human type 1diabetes with insulitis and investigated the presence of TLOs in relation to age of onset, disease duration and disease severity. RESULTS: TLOs were identified in preclinical and clinical settings of human type 1 diabetes. The main characteristics of these TLOs, including the cellular and ECM composition of reticular fibres (RFs), the presence of high endothelial venules and immune cell subtypes detected, were similar to those observed for TLOs from NOD mouse pancreases. Among 21 donors with clinical type 1 diabetes who exhibited insulitis, 12 had TLOs and had developed disease at younger age compared with those lacking TLOs. Compartmentalised TLOs with distinct T cell and B cell zones were detected in donors with short disease duration. Overall, TLOs were mainly associated with insulin-containing islets and their frequency decreased with increasing severity of beta cell loss. Parallel studies in NOD mice further revealed some differences in so far as regulatory T cells were essentially absent from human pancreatic TLOs and CCL21 was not associated with RFs. CONCLUSIONS/INTERPRETATION: We demonstrate a novel feature of pancreas pathology in type 1 diabetes. TLOs represent a potential site of autoreactive effector T cell generation in islet autoimmunity and our data from mouse and human tissues suggest that they disappear once the destructive process has run its course. Thus, TLOs may be important for type 1 diabetes progression.


Subject(s)
Diabetes Mellitus, Type 1/pathology , Tertiary Lymphoid Structures/pathology , Adolescent , Adult , Aged , Aged, 80 and over , Animals , Autoantibodies/analysis , Autoantibodies/blood , Autoimmunity/physiology , Child , Child, Preschool , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 1/immunology , Female , Humans , Islets of Langerhans/pathology , Male , Mice , Mice, Inbred NOD , Microscopy, Fluorescence , Middle Aged , Pancreas/pathology , Tertiary Lymphoid Structures/blood , Tertiary Lymphoid Structures/immunology , Young Adult
4.
Am J Transplant ; 21 Suppl 3: 17-59, 2021 09.
Article in English | MEDLINE | ID: mdl-34245223

ABSTRACT

The First World Consensus Conference on Pancreas Transplantation provided 49 jury deliberations regarding the impact of pancreas transplantation on the treatment of diabetic patients, and 110 experts' recommendations for the practice of pancreas transplantation. The main message from this consensus conference is that both simultaneous pancreas-kidney transplantation (SPK) and pancreas transplantation alone can improve long-term patient survival, and all types of pancreas transplantation dramatically improve the quality of life of recipients. Pancreas transplantation may also improve the course of chronic complications of diabetes, depending on their severity. Therefore, the advantages of pancreas transplantation appear to clearly surpass potential disadvantages. Pancreas after kidney transplantation increases the risk of mortality only in the early period after transplantation, but is associated with improved life expectancy thereafter. Additionally, preemptive SPK, when compared to SPK performed in patients undergoing dialysis, appears to be associated with improved outcomes. Time on dialysis has negative prognostic implications in SPK recipients. Increased long-term survival, improvement in the course of diabetic complications, and amelioration of quality of life justify preferential allocation of kidney grafts to SPK recipients. Audience discussions and live voting are available online at the following URL address: http://mediaeventi.unipi.it/category/1st-world-consensus-conference-of-pancreas-transplantation/246.


Subject(s)
Diabetes Mellitus, Type 1 , Kidney Transplantation , Pancreas Transplantation , Graft Survival , Humans , Quality of Life , Renal Dialysis
5.
Clin Transplant ; 35(12): e14370, 2021 12.
Article in English | MEDLINE | ID: mdl-34032328

ABSTRACT

BACKGROUND: The Coronavirus disease 2019(COVID-19) pandemic has negatively impacted worldwide organ transplantation. However, there is limited information on recipients transplanted after SARS-CoV-2 infection. A full understanding of this scenario is required, as transplantation is a life-saving procedure and COVID-19 remains an ongoing threat. METHODS: Abdominal organ transplant recipients diagnosed with COVID-19 prior to transplantation were identified by chart review and clinical data were collected. The primary outcome was the transplant outcome including graft loss, rejection and death, and reactivation of infection post-transplant. RESULTS: We identified 14 patients who received abdominal organ transplants after symptomatic PCR confirmed SARS-CoV-2 infection; four patients had a positive PCR at the time of admission for transplantation. The median time of follow-up was 79 (22-190) days. One recipient with negative PCR before transplant tested positive 9 days after transplant. One of 14 transplanted patients developed disseminated mold infection and died 86 days after transplant. During the follow-up, only one patient developed rejection; thirteen patients had favorable graft outcomes. CONCLUSIONS: We were able to perform abdominal transplantation for patients with COVID-19 before transplant, even with positive PCR at the time of transplant. Larger studies are needed to determine the time to safe transplant after SARS-CoV-2 infection.


Subject(s)
COVID-19 , Kidney Transplantation , Hospitalization , Humans , SARS-CoV-2 , Transplant Recipients
6.
Clin Transplant ; 34(12): e14123, 2020 12.
Article in English | MEDLINE | ID: mdl-33070366

ABSTRACT

A randomized trial of 150 primary kidney transplant recipients, initiated in May 2000, compared tacrolimus (TAC)/sirolimus (SRL) vs. TAC/mycophenolate mofetil (MMF) vs. cyclosporine microemulsion (CSA)/SRL (N = 50/group). All patients received daclizumab induction and maintenance corticosteroids. With current median follow-up of 18 years post-transplant, biopsy-proven acute rejection (BPAR) occurred less often in TAC/MMF (26% (13/50)), vs. the TAC/SRL (36% (18/50)) and CSA/SRL (34% (17/50)) arms combined (p = .23), with statistical significance favoring TAC/MMF (p = .05) after controlling for the multivariable (Cox model) effects of recipient age, recipient race/ethnicity, and donor age. First BPAR rate was clearly more favorable for TAC/MMF after stratifying patients by having 0-1 (N = 72) vs. 2-3 (N = 78) unfavorable baseline characteristics (recipient age <50 years, African American or Hispanic recipient, and donor age ≥50 years) (p = .02). Mean estimated glomerular filtration rate (eGFR), using the CKD-EPI formula, was consistently higher for TAC/MMF, particularly after controlling for the multivariable effect of donor age, throughout the first 96 months post-transplant (p ≤ .008). These differences were translated into an observed more favorable graft failure due to immunologic cause (CAI/TG) rate for TAC/MMF (p = .06), although no significant differences in overall death-uncensored graft loss were observed. Previously reported significantly higher study drug discontinuation and requirement for antilipid therapy rates in the SRL-assigned arms were maintained over time. Overall, these results at 18 years post-transplant more definitively show that TAC/MMF should be the gold standard for achieving optimal, long-term maintenance immunosuppression in kidney transplantation.


Subject(s)
Kidney Transplantation , Tacrolimus , Adrenal Cortex Hormones/therapeutic use , Child , Cyclosporine/therapeutic use , Drug Therapy, Combination , Graft Rejection/etiology , Graft Rejection/prevention & control , Humans , Immunosuppressive Agents/therapeutic use , Middle Aged , Mycophenolic Acid , Sirolimus , Tacrolimus/therapeutic use
7.
Kidney Int ; 95(3): 498-500, 2019 03.
Article in English | MEDLINE | ID: mdl-30784659

ABSTRACT

Focal segmental glomerulosclerosis is a glomerular disorder with a high rate of recurrence. Although kidney biopsies remain the gold standard to diagnose recurrent focal segmental glomerulosclerosis, non-invasive prognostic assays could facilitate preventive treatments and offer insight into disease pathogenicity and heterogeneity. Srivastava et al. describe a simple, cell-based assay to predict recurrence of focal segmental glomerulosclerosis. Although the study needs to be optimized and validated, its novelty is that it does not depend on the specificity of a given permeability factor.


Subject(s)
Glomerulosclerosis, Focal Segmental , Kidney Diseases , Podocytes , Humans , Recurrence , Sensitivity and Specificity
8.
Clin Transplant ; 33(7): e13619, 2019 07.
Article in English | MEDLINE | ID: mdl-31152563

ABSTRACT

Pancreas transplant achieves consistent long-term euglycemia in type 1 diabetes. Allograft thrombosis (AT) causes the majority of early graft failure. We compared outcomes of four anticoagulation regimens administered to 95 simultaneous kidney-pancreas or isolated pancreas transplanted between 1/1/2015 and 11/20/2018. Early postoperative anticoagulation regimens included the following: none, subcutaneous heparin/aspirin, with or without dextran, and heparin infusion. The regimens were empirically selected based on each surgeon's assessment of hemostasis of the operative field and personal preference. A sonographic-based global scoring system of AT is presented. The 47-month recipients and graft survival were 95% and 86%, respectively. Recipients with or without AT had similar survival. Five and four grafts were lost due to death and AT, respectively. Outcomes of prophylaxis regimens correlated with intensity of anticoagulation. Compared with no anticoagulation, an increase in hemorrhagic complications occurred exclusively with iv heparin. The higher arterial AT score found in regimens lacking antiplatelet therapy highlights the importance of early antiaggregants therapy. Abnormal fibrinolysis was associated with an increase in AT score. Platelet dysfunction, warm ischemia time, and enteric drainage were predictive of AT and, along with other known risk factors, were incorporated into an algorithm that matches intensity of early postoperative anticoagulation to the thrombotic risk.


Subject(s)
Anticoagulants/therapeutic use , Diabetes Mellitus, Type 1/surgery , Graft Rejection/drug therapy , Kidney Transplantation/adverse effects , Pancreas Transplantation/adverse effects , Postoperative Complications/drug therapy , Thrombosis/drug therapy , Female , Follow-Up Studies , Graft Rejection/diagnosis , Graft Rejection/etiology , Graft Survival , Humans , Male , Middle Aged , Postoperative Complications/diagnosis , Postoperative Complications/etiology , Prognosis , Retrospective Studies , Risk Factors , Thrombosis/diagnosis , Thrombosis/etiology
9.
Clin Transplant ; 33(5): e13532, 2019 05.
Article in English | MEDLINE | ID: mdl-30866102

ABSTRACT

BACKGROUND: Previous studies have demonstrated inferior patient and graft survival following kidney transplant (KT) in HIV+/HCV+ coinfected patients compared to HIV+/HCV- recipients. However, these studies were conducted prior to the availability of direct-acting antiviral (DAA) agents and data in the modern era are lacking. METHODS: Single center retrospective study of HIV+/HCV+ coinfected KT recipients (2007-2017). Outcomes were assessed for the pre-DAA and post-DAA (ie, after December 2013) eras including 1-year patient survival, death-censored graft survival, and acute rejection; and serious infections (defined as infections requiring admission to the intensive care unit during initial transplant hospitalization or re-admission to the hospital after discharge) within the first 6 months post-transplant. RESULTS: A total of 13 consecutive HIV+/HCV+ recipients were identified. Median time of post-transplant follow-up was 722 days. Seven patients were transplanted in the DAA era; five of them had anti-HCV Ab+ donors, with two donors being HCV NAT positive; all received DAA therapy, six of them post-transplant (median time from KT to DAA: 83 days; IQR, 54-300). All the patients in the pre-DAA era were on a protease inhibitor-containing ART regimen. One-year patient and death-censored graft survivals were 83% and 67%, respectively, for the patients transplanted in the pre-DAA era, and 100% for both outcomes in the subgroup of patients transplanted in the post-DAA era (P > 0.05). Compared to patients in the post-DAA era, those in the pre-DAA era had higher incidence of serious infections (0 vs 67%; P = 0.02). Acute rejection exclusively occurred in the pre-DAA group (n = 1; 17%). CONCLUSIONS: Outcomes of HIV+/HCV+ KT recipients, including HIV-/HCV+ to HIV+/HCV+ transplants, in the DAA era were excellent in this small cohort. Larger studies are needed.


Subject(s)
Coinfection/complications , Graft Rejection/mortality , HIV Infections/complications , Hepatitis C/complications , Kidney Failure, Chronic/mortality , Kidney Transplantation/mortality , Postoperative Complications/mortality , Adult , Aged , Antiviral Agents/therapeutic use , Coinfection/virology , Female , Follow-Up Studies , Graft Rejection/etiology , Graft Rejection/pathology , Graft Survival , HIV Infections/drug therapy , HIV Infections/virology , HIV-1/drug effects , HIV-1/isolation & purification , Hepacivirus/isolation & purification , Hepatitis C/virology , Humans , Kidney Failure, Chronic/surgery , Kidney Failure, Chronic/virology , Kidney Transplantation/adverse effects , Male , Middle Aged , Patient Readmission , Postoperative Complications/etiology , Postoperative Complications/pathology , Prognosis , Retrospective Studies , Risk Factors , Survival Rate , Time Factors , Transplant Recipients
10.
Kidney Int ; 94(6): 1151-1159, 2018 12.
Article in English | MEDLINE | ID: mdl-30301568

ABSTRACT

Studies suggest that altered renal lipid metabolism plays a role in the pathogenesis of diabetic kidney disease and that genetic or pharmacological induction of cholesterol efflux protects from the development of diabetic kidney disease and focal segmental glomerulosclerosis (FSGS). Here we tested whether altered lipid metabolism contributes to renal failure in the Col4a3 knockout mouse model for Alport Syndrome. There was an eight-fold increase in the cholesterol content in renal cortexes of mice with Alport Syndrome. This was associated with increased glomerular lipid droplets and cholesterol crystals. Treatment of mice with Alport Syndrome with hydroxypropyl-ß-cyclodextrin (HPßCD) reduced cholesterol content in the kidneys of mice with Alport Syndrome and protected from the development of albuminuria, renal failure, inflammation and tubulointerstitial fibrosis. Cholesterol efflux and trafficking-related genes were primarily affected in mice with Alport Syndrome and were differentially regulated in the kidney cortex and isolated glomeruli. HPßCD also protected from proteinuria and mesangial expansion in a second model of non-metabolic kidney disease, adriamycin-induced nephropathy. Consistent with our experimental findings, microarray analysis confirmed dysregulation of several lipid-related genes in glomeruli isolated from kidney biopsies of patients with primary FSGS enrolled in the NEPTUNE study. Thus, lipid dysmetabolism occurs in non-metabolic glomerular disorders such as Alport Syndrome and FSGS, and HPßCD improves renal function in experimental Alport Syndrome and FSGS.


Subject(s)
2-Hydroxypropyl-beta-cyclodextrin/therapeutic use , Glomerulosclerosis, Focal Segmental/drug therapy , Kidney Glomerulus/pathology , Nephritis, Hereditary/drug therapy , 2-Hydroxypropyl-beta-cyclodextrin/pharmacology , Animals , Autoantigens/genetics , Biopsy , Cholesterol/metabolism , Collagen Type IV/genetics , Doxorubicin/toxicity , Female , Glomerulosclerosis, Focal Segmental/chemically induced , Glomerulosclerosis, Focal Segmental/metabolism , Glomerulosclerosis, Focal Segmental/pathology , Humans , Lipid Metabolism/drug effects , Mice , Mice, Knockout , Nephritis, Hereditary/genetics , Nephritis, Hereditary/metabolism , Nephritis, Hereditary/pathology , Observational Studies as Topic
11.
Clin Transplant ; 32(10): e13392, 2018 10.
Article in English | MEDLINE | ID: mdl-30152116

ABSTRACT

Two major barriers to achieving long-term graft survival include patient nonadherence in taking the prescribed immunosuppression and antibody-mediated rejection(AMR). We were therefore interested in determining the prognostic impact of developing an AMR component to rejection in a prospective randomized trial of 200 kidney transplant recipients who received dual induction therapy (rATG combined with either daclizumab or alemtuzumab) and planned early corticosteroid withdrawal. With a median follow-up of 96 months post-transplant, 40/200 developed a first BPAR; 9/200 developed a second BPAR. An AMR component to rejection was observed in 70% (28/40) of cases. Percentages having C4d deposition, histopathologic evidence of acute AMR, and presence of DSAs/non-DSAs at the time of first developing the AMR component were 64.3% (18/28), 60.7% (17/28), and 53.6% (15/28), respectively. Development of an AMR component was associated with a significantly higher death-censored graft failure rate following rejection in comparison with the patient state of experiencing BPAR but without developing an AMR component (estimated hazard ratio: 4.52, P = 0.01). The observed percentage developing graft failure following development of an AMR component was 53.6% (15/28) vs only 20.0%(3/15) if it was not observed. Actuarial death-censored graft survival at 60 months following development of an AMR component was 28.3 ± 11.9%. In summary, it appears that more effective AMR prevention/treatment strategies are warranted.


Subject(s)
Graft Rejection/etiology , Isoantibodies/adverse effects , Kidney Failure, Chronic/surgery , Kidney Transplantation/adverse effects , Postoperative Complications , Adolescent , Adult , Aged , Female , Follow-Up Studies , Glomerular Filtration Rate , Graft Rejection/pathology , Graft Survival , Humans , Kidney Function Tests , Male , Middle Aged , Prognosis , Prospective Studies , Risk Factors , Survival Rate , Young Adult
12.
Clin Transplant ; 32(5): e13232, 2018 05.
Article in English | MEDLINE | ID: mdl-29488657

ABSTRACT

Body mass index (BMI) > 35-40 kg/m2 is often a contraindication, while Roux-en-Y gastric bypass (RYGB) is performed to enable kidney transplantation. This single-center retrospective study evaluated pre- and post-transplant outcomes of 31 morbidly obese patients with end-stage renal disease having RYGB before kidney transplantation between July 2009 and June 2014. Fourteen RYGB patients were subsequently transplanted. Nineteen recipients not having GB with a BMI ≥ 36 kg/m2 at transplantation were used as historical controls. Mean BMI (±SE) before RYGB was 43.5 ± 0.7 kg/m2 (range: 35.4-50.5 kg/m2 ); 87.1% (27/31) achieved a BMI < 35 kg/m2 . The percentage having improved diabetes/hypertension control was 29.0% (9/31); 25.8% (8/31) had complications (mostly minor) after RYGB. Among transplanted patients, blacks/Hispanics comprised 78.6% (11/14) and 84.2% (16/19) of RYGB and controls; 57.1% (8/14) and 63.2% (12/19) had a (mostly long-standing) pretransplant history of diabetes. While biopsy-proven acute rejection (BPAR) occurred significantly higher among RYGB vs control patients (6/14 vs 3/19, P = .03), patients developing T-cell BPAR were also significantly more likely to have a tacrolimus (TAC) trough level < 4.0 ng/mL within 3 weeks of T-cell BPAR (P = .0007). In Cox's model, the impact of having a TAC level < 4.0 ng/mg remained significant (P = .007) while the effect of RYGB was no longer significant (P = .13). Infections, graft, and patient survival were not significantly different. Despite obvious effectiveness in achieving weight loss, RYGB will need more careful post-transplant monitoring given the observed higher BPAR rate.


Subject(s)
Gastric Bypass/methods , Graft Survival , Kidney Failure, Chronic/surgery , Kidney Transplantation/methods , Obesity, Morbid/surgery , Postoperative Complications , Adult , Aged , Body Mass Index , Female , Follow-Up Studies , Glomerular Filtration Rate , Humans , Kidney Function Tests , Male , Middle Aged , Obesity, Morbid/physiopathology , Prognosis , Retrospective Studies , Risk Factors , Weight Loss , Young Adult
13.
J Am Soc Nephrol ; 27(4): 1029-41, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26400569

ABSTRACT

Nephrin belongs to a family of highly conserved proteins with a well characterized function as modulators of cell adhesion and guidance, and nephrin may have a role in metabolic pathways linked to podocyte and pancreatic ß-cell survival. However, this role is incompletely characterized. In this study, we developed floxed nephrin mice for pancreatic ß-cell-specific deletion of nephrin, which had no effect on islet size and glycemia. Nephrin deficiency, however, resulted in glucose intolerance in vivo and impaired glucose-stimulated insulin release ex vivo Glucose intolerance was also observed in eight patients with nephrin mutations compared with three patients with other genetic forms of nephrotic syndrome or nine healthy controls.In vitro experiments were conducted to investigate if nephrin affects autocrine signaling through insulin receptor A (IRA) and B (IRB), which are both expressed in human podocytes and pancreatic islets. Coimmunoprecipitation of nephrin and IRB but not IRA was observed and required IR phosphorylation. Nephrin per se was sufficient to induce phosphorylation of p70S6K in an phosphatidylinositol 3-kinase-dependent but IR/Src-independent manner, which was not augmented by exogenous insulin. These results suggest a role for nephrin as an independent modulator of podocyte and pancreatic ß-cell nutrient sensing in the fasting state and the potential of nephrin as a drug target in diabetes.


Subject(s)
Insulin/metabolism , Membrane Proteins/physiology , Receptor, Insulin/physiology , Signal Transduction/physiology , TOR Serine-Threonine Kinases/physiology , Adolescent , Animals , Child , Female , Humans , Insulin Secretion , Insulin-Secreting Cells/physiology , Male , Mice , Phosphorylation/physiology , Podocytes/physiology
14.
N Engl J Med ; 369(25): 2416-23, 2013 Dec 19.
Article in English | MEDLINE | ID: mdl-24206430

ABSTRACT

Abatacept (cytotoxic T-lymphocyte-associated antigen 4-immunoglobulin fusion protein [CTLA-4-Ig]) is a costimulatory inhibitor that targets B7-1 (CD80). The present report describes five patients who had focal segmental glomerulosclerosis (FSGS) (four with recurrent FSGS after transplantation and one with primary FSGS) and proteinuria with B7-1 immunostaining of podocytes in kidney-biopsy specimens. Abatacept induced partial or complete remissions of proteinuria in these patients, suggesting that B7-1 may be a useful biomarker for the treatment of some glomerulopathies. Our data indicate that abatacept may stabilize ß1-integrin activation in podocytes and reduce proteinuria in patients with B7-1-positive glomerular disease.


Subject(s)
B7-1 Antigen/metabolism , Glomerulosclerosis, Focal Segmental/drug therapy , Immunoconjugates/pharmacology , Abatacept , Adolescent , Adult , B7-1 Antigen/antagonists & inhibitors , Biomarkers/metabolism , Child , Female , Glomerulosclerosis, Focal Segmental/complications , Glomerulosclerosis, Focal Segmental/immunology , Humans , Immunoconjugates/therapeutic use , Male , Podocytes/drug effects , Podocytes/metabolism , Proteinuria/drug therapy , Proteinuria/etiology , Young Adult
15.
Transpl Int ; 29(10): 1117-25, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27421771

ABSTRACT

Kidney grafts are often preserved initially in static cold storage (CS) and subsequently on hypothermic machine perfusion (MP). However, the impact of CS/MP time on transplant outcome remains unclear. We evaluated the effect of prolonged CS/MP time in a single-center retrospective cohort of 59 donation after circulatory death (DCD) and 177 matched donation after brain death (DBD) kidney-alone transplant recipients. With mean overall CS/MP times of 6.0 h/30.0 h, overall incidence of delayed graft function (DGF) was higher in DCD transplants (30.5%) than DBD transplants (7.3%, P < 0.0001). In logistic regression, DCD recipient (P < 0.0001), longer CS time (P = 0.0002), male recipient (P = 0.02), and longer MP time (P = 0.08) were associated with higher DGF incidence. In evaluating the joint effects of donor type (DBD vs. DCD), CS time (<6 vs. ≥6 h), and MP time (<36 vs. ≥36 h) on DGF incidence, one clearly sees an unfavorable effect of MP time ≥36 h (P = 0.003) across each donor type and CS time stratum, whereas the unfavorable effect of CS time ≥6 h (P = 0.01) is primarily seen among DCD recipients. Prolonged cold ischemia time had no unfavorable effect on renal function or graft survival at 12mo post-transplant. Long CS/MP time detrimentally affects early DCD/DBD kidney transplant outcome when grafts were mainly preserved by MP; prolonged CS time before MP has a particularly negative impact in DCD kidney transplantation.


Subject(s)
Cold Temperature , Kidney Failure, Chronic/surgery , Kidney Transplantation/methods , Organ Preservation/methods , Adult , Cryopreservation , Delayed Graft Function , Female , Glomerular Filtration Rate , Humans , Immunosuppression Therapy , Male , Middle Aged , Perfusion , Prospective Studies , Regression Analysis , Retrospective Studies , Time Factors
16.
Transpl Int ; 29(2): 216-26, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26442829

ABSTRACT

The premise that lower TAC trough levels are associated with subsequently higher first BPAR risk during the first 12 mo post-transplant was recently questioned. Using our prospectively followed cohort of 528 adult, primary kidney transplant recipients (pooled across four randomized trials) who received reduced TAC dosing plus an IMPDH inhibitor, TAC trough levels measured at seven time points, 7, 14 days, 1, 2, 3, 6 and 9 months post-transplant, were utilized along with Cox's model to determine the multivariable significance of TAC level(t) (a continuous time-dependent covariate equaling the most recently measured TAC level prior to time t) on the hazard rate of developing first BPAR during the first 12 months post-transplant. The percentage developing BPAR during the first 12 months post-transplant was 10.2% (54/528). In univariable analysis, lower TAC level(t) was associated with a significantly higher BPAR rate (P = 0.00006), and its significance was maintained even after controlling for 2 significant baseline predictors (African-American/Hispanic Recipient and Developed DGF) in Cox's model (multivariable P = 0.0003). Use of a cutpoint, TAC level(t) <4.0 vs. ≥4.0 ng/ml, yielded an even greater association with BPAR rate (univariable and multivariable P < 0.000001), with an estimated hazard ratio of 6.33. These results suggest that TAC levels <4.0 ng/ml should be avoided during the first 12 months post-transplant when TAC is used in combination with fixed-dose mycophenolate with or without corticosteroids and induction therapy.


Subject(s)
Graft Rejection/etiology , Immunosuppressive Agents/pharmacokinetics , Kidney Transplantation/adverse effects , Tacrolimus/pharmacokinetics , Acute Disease , Adult , Aged , Delayed Graft Function/etiology , Female , Humans , Male , Middle Aged , Proportional Hazards Models , Prospective Studies , Time Factors
17.
Curr Urol Rep ; 17(1): 3, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26695405

ABSTRACT

Population of patients with end-stage renal disease increases every day. There is a vast difference in the number of patients on the waiting list for a kidney transplant, and the number of donors and the gap increases every year. The use of more marginal organs can increase the donor pool. These organs include the kidneys with small renal cell carcinomas (RCTC). There has been a number of reports in the literature about the use of these grafts for renal transplant after tumor excision and reconstruction. These grafts have been reported to be used with good renal function outcomes without an increased risk for malignancy recurrences. We present the collection of evidence for the use of kidneys with RCC for transplantation, technique used for surgical resection, and reconstruction as well as insights on the recommendations for the use of these grafts.


Subject(s)
Kidney Neoplasms/surgery , Kidney Transplantation , Cadaver , Carcinoma, Renal Cell/surgery , Humans , Kidney Failure, Chronic/surgery , Living Donors
18.
Curr Opin Organ Transplant ; 21(4): 412-8, 2016 08.
Article in English | MEDLINE | ID: mdl-27348473

ABSTRACT

PURPOSE OF REVIEW: The review analyzes the current biomarkers used in monitoring pancreas transplant, from the simple and time-tested, to more sophisticated, including markers of allo- and autoimmunity, that are likely to play a larger role in future studies. RECENT FINDINGS: Evaluation of alloimmunity includes serum levels of donor-specific antibody, and, ultimately, pancreas transplant biopsies with C4d staining. Our center has focused on markers of autoimmunity, including assessment of autoantibodies and autoreactive T cells. We have found that conversion of autoantibodies (including GAD65, IA-2, and ZnT8), or the development of a new positive autoantibody, particularly ZnT8, are associated with type 1 diabetes (T1D) recurrence in the pancreas transplant. Autoreactive T cells have also been identified in the peripheral blood, pancreas transplant and peripancreas transplant-lymph nodes, that have the potential to mediate human ß/islet cell destruction in vivo. SUMMARY: The monitoring of pancreas transplant biomarkers, particularly those associated with autoimmunity, has led to new insights into the pathogenesis of T1D. Progress in the elucidation of mechanisms of autoimmunity may lead to novel therapeutic approaches to both T1D recurrence of the pancreas transplant and perhaps also new onset T1D.


Subject(s)
Autoantibodies/blood , Biomarkers, Tumor/metabolism , Pancreas Transplantation/methods , Humans
19.
Diabetologia ; 58(2): 334-45, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25361829

ABSTRACT

AIMS/HYPOTHESIS: To better understand the implications of new-onset diabetes after transplant (NODAT), we used our prospectively followed cohort of 628 adult primary kidney transplant recipients to determine the prognostic impact of pretransplant diabetes and NODAT. METHODS: The study cohort consisted of all participants in four randomised immunosuppression trials performed at our centre since May 2000. For each cause-specific hazard analysed, Cox stepwise regression was used to determine a multivariable model of significant baseline predictors; the multivariable influence of having pretransplant diabetes and NODAT (t) (the latter defined as a zero-one, time-dependent covariate) was subsequently tested. Similar analyses of estimated glomerular filtration rate (eGFR) at 36 and 60 months post transplant were performed using stepwise linear regression. Finally, a repeated measures analysis of mean HbA1c as a function of diabetes category (pretransplant diabetes vs NODAT) and randomised trial (first to fourth) was performed. RESULTS: Median follow-up was 56 months post transplant. Patients with pretransplant diabetes comprised 23.4% (147/628), and 22.5% (108/481) of the remaining patients developed NODAT. Pretransplant diabetes had no prognostic influence on first biopsy-proven acute rejection and death-censored graft failure hazard rates, nor on eGFR, but was associated with significantly higher rates of death with a functioning graft (DWFG) (p = 0.003), DWFG due to a cardiovascular event (p = 0.005) and infection that required hospitalisation (p = 0.03). NODAT (t) had no unfavourable impact on any of these hazard rates nor on eGFR, with actuarial freedom from DWFG remaining at over 90% among patients in pre- and post-NODAT states at 72 months post transplant/NODAT. Mean HbA1c for patients in the first to fourth randomised trials, averaged across diabetes category, decreased by trial (7.28%, 6.92%, 6.87% and 6.64% [56.1, 52.1, 51.6 and 49.1 mmol/mol], respectively; p = 0.02). CONCLUSIONS/INTERPRETATION: Less-than-expected post-NODAT risk for graft loss and death may exist in the current climate of tighter glucose monitoring post transplant.


Subject(s)
Diabetes Mellitus/etiology , Kidney Transplantation/adverse effects , Transplant Recipients/statistics & numerical data , Cohort Studies , Diabetes Mellitus/blood , Diabetes Mellitus/mortality , Female , Follow-Up Studies , Graft Rejection , Graft Survival , Humans , Immunosuppressive Agents , Kidney Transplantation/mortality , Male , Middle Aged , Prognosis , Prospective Studies , Risk Factors
20.
Curr Diab Rep ; 15(12): 121, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26547222

ABSTRACT

Type 1 diabetes recurrence (T1DR) affecting pancreas transplants was first reported in recipients of living-related pancreas grafts from twins or HLA identical siblings; given HLA identity, recipients received no or minimal immunosuppression. This observation provided critical evidence that type 1 diabetes (T1D) is an autoimmune disease. However, T1DR is traditionally considered very rare in immunosuppressed recipients of pancreas grafts from organ donors, representing the majority of recipients, and immunological graft failures are ascribed to chronic rejection. We have been performing simultaneous pancreas-kidney (SPK) transplants for over 25 years and find that 6-8 % of our recipients develop T1DR, with symptoms usually becoming manifest on extended follow-up. T1DR is typically characterized by (1) variable degree of insulitis and loss of insulin staining, on pancreas transplant biopsy (with most often absent), minimal to moderate and rarely severe pancreas, and/or kidney transplant rejection; (2) the conversion of T1D-associated autoantibodies (to the autoantigens GAD65, IA-2, and ZnT8), preceding hyperglycemia by a variable length of time; and (3) the presence of autoreactive T cells in the peripheral blood, pancreas transplant, and/or peripancreatic transplant lymph nodes. There is no therapeutic regimen that so far has controlled the progression of islet autoimmunity, even when additional immunosuppression was added to the ongoing chronic regimens; we hope that further studies and, in particular, in-depth analysis of pancreas transplant biopsies with recurrent diabetes will help identify more effective therapeutic approaches.


Subject(s)
Autoimmunity , Diabetes Mellitus, Type 1/immunology , Pancreas Transplantation , Autoantibodies/blood , Autoantibodies/immunology , Diabetes Mellitus, Type 1/surgery , Humans , Pancreas/immunology , Pancreas/surgery , Recurrence
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