Cardio-hepatic risk assessment by CMR imaging in liver transplant candidates.

BACKGROUND: The preoperative workup of orthotopic liver transplantation (OLT) patients is practically complex given the need for multiple imaging modalities. We recently demonstrated in our proof-of-concept study the value of a one-stop-shop approach using cardiovascular MRI (CMR) to address this complex problem. However, this approach requires further validation in a larger cohort, as detection of hepatocellular carcinoma (HCC) as well as cardiovascular risk assessment is critically important in these patients. We hypothesized that coronary risk assessment and HCC detectability is acceptable using the one-stop-shop CMR approach. METHODS: In this observational study, patients underwent CMRI evaluation including cardiac function, stress CMR, thoracoabdominal MRA, and abdominal MRI on a standard MRI scanner in one examination. RESULTS: Over 8 years, 252 OLT candidates underwent evaluation in the cardiac MRI suit. The completion rates for each segment of the CMR examination were 99% for function, 95% completed stress CMR, 93% completed LGE for viability, 85% for liver MRI, and 87% for MRA. A negative CMR stress examination had 100% CAD event-free survival at 12 months. A total of 63 (29%) patients proceeded to OLT. Explant pathology confirmed detection/exclusion of HCC. CONCLUSIONS: This study further defines the population suitable for the one-stop-shop CMR concept for preop evaluation of OLT candidates providing a road map for integrated testing in this complex patient population for evaluation of cardiac risk and detection of HCC lesions.

Proteasome inhibition with bortezomib: an effective therapy for severe antibody mediated rejection after renal transplantation.

Antibody-mediated rejection (AMR) following renal transplantation is less responsive to conventional anti-rejection therapies. Plasmapheresis (PP), intravenous immunoglobulin (IVIg), rabbit antithymocyte globulin (rATG) and rituximab deplete immature B-cells but not mature plasma cells. The proteasome inhibitor bortezomib has activity against mature plasma cell, the source of damaging donor-specific antibody (DSA).We present the successful use of bortezomib in 2 patients who developed AMR following kidney transplantation. The first patient was a 54-year-old white female who received living-unrelated kidney transplantation from her husband. She developed severe AMR early after transplantation with rising DSA titers consistent with an anamnestic immune response by memory cells to the donor antigens. Renal function deteriorated despite treatment with pulse methylprednisolone (MP), PP and IVIg. After initiation of therapy with bortezomib, DSA titers became negative and serum creatinine returned to baseline with histological resolution of AMR. The second patient was a 19-year-old white male who received deceased donor kidney transplantation and developed AMR within 2 weeks, refractory to therapy with pulse MP, PP and IVIg with rising DSA. Bortezomib use resulted in disappearance of DSA and renal function improvement. Both patients tolerated the treatment well with stable renal function at last follow-up. The novel mechanisms of action and preliminary results with bortezomib are encouraging, but require larger studies and longer follow-up.

Alemtuzumab preconditioning with tacrolimus monotherapy-the impact of serial monitoring for donor-specific antibody.

BACKGROUND: Antibody preconditioning with tacrolimus monotherapy has allowed many renal allograft recipients to be maintained on spaced weaning. METHODS: Of 279 renal allograft recipients transplanted between March 2003 and December 2004, 222 (80%) had spaced weaning (i.e., reduction of tacrolimus monotherapy dosing to every other day, three times a week, twice a week, or once a week) attempted. Routine monitoring for donor-specific antibody (DSA) was begun in September 2004. Mean follow-up is 34+/-6.5 months after transplantation and 26+/-8.1 months after the initiation of spaced weaning. RESULTS: One hundred and twenty-two (44%) patients remained on spaced weaning. One- and 2-year actual patient/graft survival was 99%/99%, and 97%/96%. Fifty-six (20%) patients experienced acute rejection after initiation of spaced weaning. One- and 2-year actual patient/graft survival was 100%/98%, and 94%/78%. Forty-two (15%) patients with stable renal function had spaced weaning stopped because of the development of DSA, which disappeared in 17 (40%). One- and 2-year actual patient and graft survival was 100% and 100%. CONCLUSION: Adult renal transplant recipients who are able to be maintained on spaced weaning have excellent outcomes. Patients with stable renal function who have reversal of weaning because of the development of DSA also have excellent outcomes. Routine monitoring for DSA may allow patients to avoid late rejection after spaced weaning.

Alemtuzumab induction and tacrolimus monotherapy in pancreas transplantation: One- and two-year outcomes.

BACKGROUND: Alemtuzumab (Campath-1H) induction with tacrolimus monotherapy has been shown to provide effective immunosuppression for kidney, liver, lung, and small bowel transplantation. This drug combination was evaluated in pancreas transplant recipients. METHODS: Sixty consecutive pancreas transplants (30 simultaneous pancreas-kidney, 20 pancreas after kidney, and 10 pancreas alone) were carried out under this protocol between July 2003 to January 2005. The mean follow-up was 22 months (range 17-33). RESULTS: One-year patient, pancreas, and kidney allograft survival were 95%, 93%, and 90%, respectively. With 22 months follow-up, patient, pancreas, and kidney survival were 94%, 89%, and 87%, respectively. The rejection rate was 30% (18/60), with four patients (7%) experiencing steroid-resistant rejection. Major infection occurred in three (5%) patients resulting in two (3.3%) deaths from disseminated histoplasmosis and a herpes virus infection. One patient with cryptococcal meningitis was successfully treated. Seven (11.7%) patients experienced cytomegalovirus infection, all of whom responded to treatment with ganciclovir. One (1.7%) case of polymorphic posttransplant lymphoproliferative disease was seen, which regressed with a temporary discontinuation of tacrolimus and high-dose ganciclovir. The mean serum creatinine of the 30 simultaneous pancreas-kidney transplants at one year posttransplant was 1.37+/-0.33 mg/ml. The preexisting creatinine in pancreas after kidney transplants was not adversely affected by this immunosuppressive protocol. CONCLUSION: A single dose of perioperative alemtuzumab followed by daily tacrolimus monotherapy provides effective immunosuppression for pancreas transplantation, but the optimal use of this drug combination is not yet clear.

Pancreas transplantation under alemtuzumab (Campath-1H) and tacrolimus: Correlation between low T-cell responses and infection.

BACKGROUND: Alemtuzumab induction and tacrolimus-based immunosuppression has been effective in pancreas transplantation. Despite the encouraging results of this minimalistic approach to immunosuppression, infection still remains a significant cause of morbidity. The Cylex ImmuKnow [corrected] assay was used in this study to compare pancreas recipient clinical states (stable, rejection, infection) with T cell responses. METHODS: Blood samples were taken from pancreas recipients pretransplant and at approximately three-month intervals posttransplant for analysis of T cell responses. When possible, T cell responses were also quantified during changes in clinical status (infection or rejection). RESULTS: A range between 100-300 ng/ml adenosine triphosphate (ATP) was found in stable patients (mean 194+/-123, n = 51) with good graft function and no infection or rejection. A low T cell response was highly correlated with infectious states. The fourteen patients with infections/posttransplant lymphoproliferative disease had a mean ATP of 48 ng/ml. Risk hazard analysis showed that patients with ATP levels <100 ng/ml were four to seven times more susceptible to infection compared to stable patients. Four patients with rejection showed a T cell response of 550 ng/ml ATP, which was statistically significant compared to stable patients, although the sampling numbers (9) were too small to be conclusive. CONCLUSION: The Cylex ImmuKnow [corrected] assay is a valuable tool to more precisely modulate immunosuppression in pancreas transplant patients. In particular, the assay is extremely useful in detecting overly immunosuppressed patients vulnerable to infections.

Outcomes of Early Steroid Withdrawal in Recipients of Deceased-Donor Expanded Criteria Kidney Transplants in the Era of Induction Therapy.

OBJECTIVES: This study explored the safety of early steroid withdrawal in recipients of expanded criteria deceased-donor kidney transplants. MATERIALS AND METHODS: Using the Organ Procurement and Transplant Network-United Network of Organ Sharing database, we identified patients who underwent expanded criteria deceased-donor kidney transplant between January 2000 and December 2008 after receiving induction with rabbit-antithymocyte globulin (n = 3717), alemtuzumab (n = 763), or interleukin 2 blocking agent (n = 2600) followed by calcineurin inhibitor and mycophenolate mofetil-based maintenance with and without steroid therapy. RESULTS: Adjusted overall graft survival (hazard ratio 1.32; 95% confidence interval, 1.1-1.56; P = .002) and patient survival (hazard ratio 1.46, 95% confidence interval, 1.16-1.83, P = .001) were inferior, whereas death-censored graft survival (hazard ratio 1.13; 95% confidence interval, 0.87-1.47; P = .35) was similar for chronic steroid maintenance versus early steroid withdrawal groups in rabbit-antithymocyte globulin-induced patients. Graft and patient outcomes were similar for chronic steroid maintenance versus early steroid withdrawal groups among alemtuzumab and interleukin 2 blocking agent-induced patients. Among rabbit-antithymocyte globulin-induced patients, adjusted overall graft survival (hazard ratio 1.57; 95% confidence interval, 1.2-2.0; P < .001) and patient survival (hazard ratio 1.5; 95% CI, 1.15-2.1; P = .004) were inferior, whereas death-censored graft survival (hazard ratio 1.5; 95% confidence interval, 0.97-2.43; P = .07) trended inferior for chronic steroid maintenance versus early steroid withdrawal groups in recipients > 60 years old (n = 1729). CONCLUSIONS: Our study showed safety of early steroid withdrawal in recipients of expanded criteria deceased-donor kidney transplants who underwent perioperative induction followed by calcineurin inhibitor and mycophenolate mofetil maintenance. Among rabbit-antithymocyte globulin-induced patients, chronic steroid maintenance was associated with inferior graft and patient outcomes, an effect limited to older recipients.

Impact of steroid maintenance on the outcomes in first-time deceased donor kidney transplant recipients: Analysis by induction type.

AIM: To analyze the impact of steroid maintenance on the outcomes in kidney transplant recipients stratified by induction agent received. METHODS: Patients who underwent first-time deceased donor kidney transplantation between 2000 and 2008 after receiving induction therapy with rabbit-antithymocyte globulin (r-ATG), alemtuzumab or an interleukin-2 receptor blocker (IL-2B) and discharged on a calcineurin inhibitor (CNI)/mycophenolate mofetil (MMF)-regimen along with or without steroids were identified from the Organ Procurement and Transplant Network/United Network of Organ Sharing database. For each induction type, adjusted overall and death-censored graft as well as patient survivals were compared between patients discharged on steroid vs no steroid. Among r-ATG induced patients, analysis was repeated after splitting the group into low and high immune risk groups. RESULTS: Among the 37217 patients included in the analysis, 17863 received r-ATG (steroid = 13001, no-steroid = 4862), 3028 alemtuzumab (steroid = 852, no-steroid = 2176) and 16326 IL-2B (steroid = 15008, no-steroid = 1318). Adjusted overall graft survival was inferior (HR = 1.16, 95%CI: 1.06-1.27, P = 0.002) with similar death-censored graft survival (HR = 0.99, 95%CI: 0.86-1.14, P = 0.86) for steroid vs no-steroid groups in r-ATG induced patients. Both adjusted overall and death-censored graft survivals for steroid vs no-steroid groups were similar in alemtuzumab (HR = 0.92, 95%CI: 0.73-1.15, P = 0.47 and HR = 0.87, 95%CI: 0.62-1.22, P = 0.43 respectively) and IL-2B (HR = 1.05, 95%CI: 0.91-1.21, P = 0.48 and HR = 0.94, 95%CI: 0.75-1.18, P = 0.60 respectively) induced groups. Adjusted patient survivals were inferior for steroid vs no-steroid groups in r-ATG induced (HR = 1.31, 95%CI: 1.15-1.49, P < 0.001) but similar in alemtuzumab (HR = 1.02, 95%CI: 0.75-1.38, P = 0.92) and IL-2B (HR = 1.17, 95%CI: 0.97-1.40, P = 0.10) induced patients. Among the r-ATG induced group there were 4346 patients in the low immune risk and 13517 patients in the high immune risk group. Adjusted overall graft survivals were inferior for steroid vs no steroid groups in both low immune (HR = 1.34, 95%CI: 1.09-1.64, P = 0.001) and high immune (HR = 1.18, 95%CI: 1.07-1.30, P = 0.005) risk groups. Adjusted death-censored graft survivals for steroid vs no steroid groups were similar in both low (HR = 1.06, 95%CI: 0.78-1.45, P = 0.70) and high (HR = 1.04, 95%CI: 0.98-1.20, P = 0.60) immune risk groups. Adjusted patient survivals were inferior for steroid vs no steroid groups in both low immune (HR = 1.54, 95%CI: 1.18-2.02, P < 0.001) and high immune (HR = 1.32, 95%CI: 1.16-1.51, P = 0.002) risk groups. Overall, there were significantly higher deaths from infections and cardiovascular causes in patients maintained on steroids. CONCLUSION: Our study showed an association between steroid addition to a CNI/MMF-maintenance regimen and increased death with functioning graft in patients receiving r-ATG induction for first-time deceased donor kidney transplantation.

Exploratory use of cardiovascular magnetic resonance imaging in liver transplantation: a one-stop shop for preoperative cardiohepatic evaluation.

BACKGROUND: Preoperative cardiovascular risk stratification in orthotopic liver transplantation candidates has proven challenging due to limitations of current noninvasive modalities. Additionally, the preoperative workup is logistically cumbersome and expensive given the need for separate cardiac, vascular, and abdominal imaging. We evaluated the feasibility of a "one-stop shop" in a magnetic resonance suite, performing assessment of cardiac structure, function, and viability, along with simultaneous evaluation of thoracoabdominal vasculature and liver anatomy. METHODS: In this pilot study, patients underwent steady-state free precession sequences and stress cardiac magnetic resonance (CMR), thoracoabdominal magnetic resonance angiography, and abdominal magnetic resonance imaging (MRI) on a standard MRI scanner. Pharmacologic stress was performed using regadenoson, adenosine, or dobutamine. Viability was assessed using late gadolinium enhancement. RESULTS: Over 2 years, 51 of 77 liver transplant candidates (mean age, 56 years; 35% female; mean Model for End-stage Liver Disease score, 10.8; range, 6-40) underwent MRI. All referred patients completed standard dynamic CMR, 98% completed stress CMR, 82% completed late gadolinium enhancement for viability, 94% completed liver MRI, and 88% completed magnetic resonance angiography. The mean duration of the entire study was 72 min, and 45 patients were able to complete the entire examination. Among all 51 patients, 4 required follow-up coronary angiography (3 for evidence of ischemia on perfusion CMR and 1 for postoperative ischemia), and none had flow-limiting coronary disease. Nine proceeded to orthotopic liver transplantation (mean 74 days to transplantation after MRI). There were six ascertained mortalities in the nontransplant group and one death in the transplanted group. Explant pathology confirmed 100% detection/exclusion of hepatocellular carcinoma. No complications during CMR examination were encountered. CONCLUSIONS: In this proof-of-concept study, it appears feasible to perform a comprehensive, efficient, and safe preoperative liver transplant imaging in a CMR suite-a one-stop shop, even in seriously ill patients.

Effect of high-dose erythropoietin on graft function after kidney transplantation: a randomized, double-blind clinical trial.

BACKGROUND AND OBJECTIVES: Delayed graft function (DGF) is associated with adverse long-term outcomes after deceased-donor kidney (DDK) transplantation. Ischemia-reperfusion injury plays a crucial role in the development of DGF. On the basis of promising animal data, this study evaluated any potential benefits of erythropoietin-alfa (EPO-α) given intra-arterially at the time of reperfusion of renal allograft on the degree of allograft function, as well as tubular cell injury measured by urinary biomarkers in the early post-transplant period. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: A prospective, randomized, double-blind, placebo-controlled clinical trial was conducted to evaluate the influence of EPO-α administered intraoperatively on the outcomes of DDK transplantations performed at the study center between March 2007 and July 2009. RESULTS: Seventy-two patients were randomly assigned to EPO-α (n=36) or placebo (n=36). The incidences of DGF, slow graft function, and immediate graft function did not significantly differ between the treatment and control groups (41.7% versus 47.2%, 25.0% versus 36.1%, and 33.3% versus 16.7%, respectively; P=0.24). The groups had similar levels of urinary biomarkers, including neutrophil gelatinase-associated lipocalin and IL-18 at multiple times points soon after transplantation; urinary output during the first 3 postoperative days; 1-month renal function; and BP readings, hemoglobin, and adverse effects during the first month. CONCLUSIONS: This study did not show any clinically demonstrable beneficial effects of high-dose EPO-α given intra-arterially during the early reperfusion phase in DDK transplant recipients in terms of reducing the incidence of DGF or improving short-term allograft function.

Influence of induction modality on the outcome of deceased donor kidney transplant recipients discharged on steroid-free maintenance immunosuppression.

BACKGROUND: Over last several years, alemtuzumab induction has been increasingly used in kidney transplantation especially in patients maintained on steroid-free immunosuppression. It is unclear which induction agent is associated with better graft and patient outcomes in these patients. METHODS: Using Organ Procurement and Transplant Network/United Network of Organ Sharing database, graft and patient survivals were compared with multivariate analysis for deceased donor kidney transplant recipients from January 2000 to December 2008 who received induction with rabbit-antithymocyte globulin (r-ATG), alemtuzumab, or an interleukin-2 (IL-2) receptor blocker and were discharged on a calcineurin inhibitor/mycophenolate mofetil/steroid-free immunosuppression. RESULTS: When compared with r-ATG (n=5348), adjusted graft survival was inferior with alemtuzumab (n=2428, hazards ratio [HR] 1.26, 95% confidence interval [CI] 1.10-1.43, P=0.001) and IL-2 receptor blocker (n=1396, HR 1.19, 95% CI 1.01-1.39, P=0.04) inductions and patient survival was inferior with alemtuzumab (HR 1.29, 95% CI 1.08-1.55, P=0.006). Alemtuzumab induction was associated with higher adjusted graft failure risks in patients with panel reactive antibody more than 20% (HR 1.30, 95% CI 1.01-1.68, P=0.04), recipients of expanded criteria donor kidneys (HR 1.58, 95% CI 1.23-2.02, P<0.001), and kidneys with cold ischemia time more than 24 hr (HR 1.31, 95% CI 1.04-1.65, P=0.02) and higher patient death risks in recipients of expanded criteria donor kidney (HR 1.66, 95% CI 1.20-1.30, P=0.002) and kidneys with cold ischemia time more than 24 hr (HR 1.44, 95% CI 1.04-2.00, P=0.03). Adjusted graft survival rates were similar for different induction agents in the low-immune risk group. CONCLUSIONS: When compared with alemtuzumab and IL-2 receptor blocker, r-ATG induction seems to be associated with superior outcomes in deceased donor kidney transplant recipients maintained on calcineurin inhibitor/mycophenolate mofetil/steroid-free regimen.

The role of liver-derived regulatory dendritic cells in prevention of type 1 diabetes.

Development of type 1 diabetes has been attributed to T-cell-mediated autoimmunity, which is regulated by antigen-presenting cells. To study the role of liver-derived B220(+) regulatory dendritic cells (DCs) in the development of diabetes in non-obese diabetic (NOD) mice, we found that liver 220(+) DCs could easily be propagated from young NOD mice, but that such propagation was extremely difficult from mice older than 11 weeks, when insulitis began. This was not simply an age-related phenomenon, because liver B220(+) DCs were readily propagated from both young and old congenic non-obese diabetic-resistant (NOR) and normal BALB/c mice. It was therefore speculated that the development of diabetes might be associated with a lack of precursors of B220(+) DC in the liver in this animal model. Unfortunately, the specific marker for precursors of liver B220(+) DC has not been identified. An alternative approach to supplement liver B220(+) DCs by intravenous administration significantly inhibited the development of diabetes by inducing T-cell hyporesponsiveness via enhancement of their apoptotic death. Liver B220(+) DCs were capable of effectively presenting antigens but, unlike plasmacytoid DCs, did not express CD11c and were not interferon-alpha producers. These observations may throw new light on the aetiopathology of type 1 diabetes.

Mechanistic insights into achievement of cardiac allograft long-term survival by treatment with immature dendritic cells and sub-dose sirolimus.

BACKGROUND: Administration of immature dendritic cells (DC) prolongs but does not result in indefinite allograft survival. We attempted to achieve this goal by adding a sub-therapeutic dose of immunosuppression. METHODS: DC propagated from B10 (H-2(b)) mouse bone marrow (BM) were transfected with nuclear factor-kappaB (NF-kappaB)-binding-site-specific oligodeoxyribonucleotide (ODN). The allostimulatory activity of transfected and normal DC were examined in mixed-lymphocyte reaction (MLR) and cytotoxic T-lymphocyte (CTL) assays in vitro, and their influence on allograft survival by systemic administration of DC in vivo. RESULTS: Transfection of DC with NF-kappaB ODN resulted in complete abrogation of NF-kappaB activity and inhibition of co-stimulation. Allogeneic (C3H, H-2(k)) T cells stimulated by ODN DC demonstrated impairment in MLR and CTL activity. Administration of ODN DC significantly prolonged B10 allograft survival. In contrast to cyclosporine, which failed to enhance the effect of ODN DC, a combination of ODN DC with sirolimus at 6 mg/kg/day for 6 days achieved long-term survival in all allografts. This was associated with low CTL activity of either graft-infiltrating cells or splenic T cells and increased TUNEL-positive cells in T-cell areas of recipient mesenteric lymph nodes. Analysis of transcription factor nuclear translocation with Cellomics indicated that stimulation with ODN DC showed inhibited T-cell nuclear translocation of signal transducer and activator of transcription (Stat)1 and Stat3, extracellular signal-related kinase (ERK) and activating transcription factor (ATF)-2, but not NF-kappaB and P38, compared with mature DC. The selective inhibition was enhanced by sirolimus, but not cyclosporine. CONCLUSIONS: Sirolimus enhances immature DC tolerogenicity by induction of T-cell apoptosis, and promotes immature DC-induced inhibition of Stat1, ERK and ATF-2 activation.

Pancreatic transplantation at the University of Pittsburgh.

Campath-1H preconditioning with tacrolimus monotherapy is an effective immunosuppressive regimen for pancreas transplantation, with acceptable patient and graft survival rates early after transplantation. Rejection rates are low under this protocol if the tacrolimus level is kept consistently >10 ng/ml. This immunosuppressive protocol, combined with recent technical refinements, has resulted in lower rates of thrombosis and overall complications. Pancreatic transplantation en-bloc with visceral grafts has the following unique features: Diabetes is a rare indication, and HLA matching is not required. The gland is immunologically protected by the simultaneously transplanted visceral organs. Disease gravity, surgical complexity and gut alloimmunity influence the overall pancreatic allograft survival. The current UNOS listing criteria and data registry should be modified for obvious logistic and scientific reasons.