Hepatic ischemia/reperfusion injury can be modulated with thymoglobulin induction therapy

Small bowel transplant - novel indications and recent progress

INTRODUCTION

Advances in the management of intestinal failure have led to a reduction in the number of intestinal transplants. The number of bowel transplants has been mainly stable even though a slight increase has been observed in the last 5 years.

AREAS COVERED

Standard indication includes patients with a reasonable life expectancy. Recent progress can be deduced by the increased number of intestine transplants in adults: this is due to the continuous improvement of 1-year graft survival worldwide (without differences in 3- and 5-year) associated with better abdominal wall closure techniques. This review aims to provide an update on new indications and changes in trends of pediatric and adult intestine transplantation. This analysis, which stretches through the past 5 years, is based on a collection of related manuscripts from PubMed.

EXPERT COMMENTARY

Intestinal transplants should be solely intended for a group of individuals for whom indications for transplantation are clear and both medical and surgical rehabilitations have failed. Nevertheless, many protocols developed over the years have not yet solved the key question represented by the over-immunosuppression. Novel indications and recent progress in the bowel transplant field, minimal yet consistent, represent a pathway to be followed.

Immunosuppression in Donation After Circulatory Death Liver Transplantation: Can Induction Modify Graft Survival?

Recipients of donation after circulatory death (DCD) LTs historically have an increased risk of graft failure. Antibody induction (AI) with antithymocyte globulin (ATG) or anti-interleukin 2 receptor (anti-IL2R) immunotherapy may decrease the incidence of graft failure by mitigating ischemia/reperfusion injury. A retrospective review of the United Network for Organ Sharing (UNOS) database for LTs between 2002 and 2015 was conducted to determine whether ATG or anti-IL2R AI was associated with graft survival in DCD. A secondary endpoint was postoperative renal function as measured by estimated glomerular filtration rate at 6 and 12 months. Among DCD recipients, ATG (hazard ratio [HR] = 0.71; P = 0.03), but not anti-IL2R (HR = 0.82; P = 0.10), was associated with a decrease in graft failure at 3 years when compared with recipients without AI. ATG (HR = 0.90; P = 0.02) and anti-IL2R (HR = 0.94; P = 0.03) were associated with a decreased risk of graft failure in donation after brain death (DBD) liver recipients at 3 years compared with no AI. When induction regimens were compared between DCD and DBD, only ATG (HR = 1.19; P = 0.19), and not anti-IL2R (HR = 1.49; P < 0.01) or no AI (HR = 1.77; P < 0.01), was associated with similar survival between DCD and DBD. In conclusion, AI therapy with ATG was associated with improved longterm liver allograft survival in DCD compared with no AI. ATG was associated with equivalent graft survival between DCD and DBD, suggesting a beneficial role of immune cell depletion in DCD outcomes.

Induction immunosuppression in adults undergoing liver transplantation: a network meta-analysis

BACKGROUND

Liver transplantation is considered the definitive treatment for people with liver failure. As part of post-liver transplantation management, immunosuppression (suppressing the host immunity) is given to prevent graft rejections. Immunosuppressive drugs can be classified into those that are used for a short period during the beginning phase of immunosuppression (induction immunosuppression) and those that are used over the entire lifetime of the individual (maintenance immunosuppression), because it is widely believed that graft rejections are more common during the first few months after liver transplantation. Some drugs such as glucocorticosteroids may be used for both induction and maintenance immunosuppression because of their multiple modalities of action. There is considerable uncertainty as to whether induction immunosuppression is necessary and if so, the relative efficacy of different immunosuppressive agents.

OBJECTIVES

To assess the comparative benefits and harms of different induction immunosuppressive regimens in adults undergoing liver transplantation through a network meta-analysis and to generate rankings of the different induction immunosuppressive regimens according to their safety and efficacy.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, Science Citation Index Expanded, World Health Organization International Clinical Trials Registry Platform, and trials registers until July 2019 to identify randomised clinical trials in adults undergoing liver transplantation.

SELECTION CRITERIA

We included only randomised clinical trials (irrespective of language, blinding, or status) in adults undergoing liver transplantation. We excluded randomised clinical trials in which participants had multivisceral transplantation and those who already had graft rejections.

DATA COLLECTION AND ANALYSIS

We performed a network meta-analysis with OpenBUGS using Bayesian methods and calculated the odds ratio (OR), rate ratio, and hazard ratio (HR) with 95% credible intervals (CrIs) based on an available case analysis, according to National Institute of Health and Care Excellence Decision Support Unit guidance.

MAIN RESULTS

We included a total of 25 trials (3271 participants; 8 treatments) in the review. Twenty-three trials (3017 participants) were included in one or more outcomes in the review. The trials that provided the information included people undergoing primary liver transplantation for various indications and excluded those with HIV and those with renal impairment. The follow-up in the trials ranged from three to 76 months, with a median follow-up of 12 months among trials. All except one trial were at high risk of bias, and the overall certainty of evidence was very low. Overall, approximately 7.4% of people who received the standard regimen of glucocorticosteroid induction died and 12.2% developed graft failure. All-cause mortality and graft failure was lower with basiliximab compared with glucocorticosteroid induction: all-cause mortality (HR 0.53, 95% CrI 0.31 to 0.93; network estimate, based on 2 direct comparison trials (131 participants; low-certainty evidence)); and graft failure (HR 0.44, 95% CrI 0.28 to 0.70; direct estimate, based on 1 trial (47 participants; low-certainty evidence)). There was no evidence of differences in all-cause mortality and graft failure between other induction immunosuppressants and glucocorticosteroids in either the direct comparison or the network meta-analysis (very low-certainty evidence). There was also no evidence of differences in serious adverse events (proportion), serious adverse events (number), renal failure, any adverse events (proportion), any adverse events (number), liver retransplantation, graft rejections (any), or graft rejections (requiring treatment) between other induction immunosuppressants and glucocorticosteroids in either the direct comparison or the network meta-analysis (very low-certainty evidence). However, because of the wide CrIs, clinically important differences in these outcomes cannot be ruled out. None of the studies reported health-related quality of life.

FUNDING

the source of funding for 14 trials was drug companies who would benefit from the results of the study; two trials were funded by neutral organisations who have no vested interests in the results of the study; and the source of funding for the remaining nine trials was unclear.

AUTHORS' CONCLUSIONS

Based on low-certainty evidence, basiliximab induction may decrease mortality and graft failure compared to glucocorticosteroids induction in people undergoing liver transplantation. However, there is considerable uncertainty about this finding because this information is based on small trials at high risk of bias. The evidence is uncertain about the effects of different induction immunosuppressants on other clinical outcomes, including graft rejections. Future randomised clinical trials should be adequately powered, employ blinding, avoid post-randomisation dropouts (or perform intention-to-treat analysis), and use clinically important outcomes such as mortality, graft failure, and health-related quality of life.

Association of More Intensive Induction With Less Acute Rejection Following Intestinal Transplantation: Results of 445 Consecutive Cases From a Single Center

BACKGROUND

In intestinal transplantation, acute cellular rejection (ACR) remains a significant challenge to achieving long-term graft survival. It is still not clear which are the most important prognostic factors.

METHODS

We performed a Cox multivariable analysis of the hazard rates of developing any ACR, severe ACR, and cause-specific graft loss during the first 60 months posttransplant among 445 consecutive intestinal transplant recipients at our institution since 1994. Of particular interest was to determine the prognostic influence of induction type: rabbit antithymocyte globulin (rATG; 2 mg/kg × 5)/rituximab (150 mg/m × 1; begun in 2013), alemtuzumab (2001-2011), and less intensive forms.

RESULTS

First ACR and severe ACR occurred in 61.3% (273/445) and 22.2% (99/445) of cases. The following 3 multivariable predictors were associated with significantly lower hazard rates of developing ACR and severe ACR: transplant type modified multivisceral or full multivisceral (P = 0.0009 and P < 0.000001), rATG/rituximab induction (P < 0.000001 and P < 0.01), and alemtuzumab induction (P = 0.004 and P = 0.07). For both ACR and severe ACR, the protective effects of rATG/rituximab and alemtuzumab were highly significant (P ≤ 0.000005 for ACR; P ≤ 0.01 for severe ACR) but only during the first 24 days posttransplant (when the ACR hazard rate was at its peak). The prognostic effects of rATG/rituximab and alemtuzumab on ACR/severe ACR disappeared beyond 24 days posttransplant (ie, nonproportional hazards). While significant protective effects of both rATG/rituximab and alemtuzumab existed during the first 6 months posttransplant for the hazard rate of graft loss-due-to-rejection (P = 0.01 and P = 0.003), rATG/rituximab was additionally associated with a consistently lower hazard rate of graft loss-due-to-infection (P = 0.003). All significant effects remained after controlling for the propensity-to-be-transplanted since 2013.

CONCLUSIONS

More intensive induction was associated with a significant lowering of ACR risk, particularly during the early posttransplant period.

Safety of Antithymocyte Globulin in Patients Undergoing Liver Transplantation With Livers From Donation After Circulatory Death Donors

Background: Studies suggest that rabbit-antithymocyte globulin (rATG) decreases biliary complications (BCs) after donation-after-circulatory-death-donor liver transplantation (DCD LTx), but safety data are lacking. Objective: Our aim was to assess the safety of rATG for this indication. The secondary end point was efficacy of rATG for this indication. Methods: Adult recipients of DCD LTx were divided into 2 cohorts: protocolized use of rATG in the modern era (July 1, 2013, to December 31, 2016) and a historical control without rATG (January 1, 2005, to June 30, 2013). Incidence of infection, leukopenia, and thrombocytopenia were compared for the safety assessment, incidence of BCs, ischemic cholangiopathy (IC), and transplant outcomes for the efficacy assessment. Results: A total of 83 patients met inclusion criteria: 42 in the historical cohort and 41 in the modern cohort. The modern cohort had significantly fewer bacterial infections at 3 months (historical 54.8% vs modern 23%; P = 0.004) and 1 year (historical 62.1% vs modern 34.2%, P = 0.004). The modern cohort also had fewer fungal infections at these time points (historical 33.3% and 47.9% vs modern 15% and 15%; P = 0.001). There were no significant differences in platelet or white blood cell reduction between groups. There was a nonsignificant, but numerical, trend toward reduced IC/BC in the modern cohort at 1 year (IC: historical 30.1% vs modern 13.2%, P = 0.08; BC: historical 51% vs modern 37.5%, P = 0.13). There was no difference in graft/patient survival. Conclusion and Relevance: Our data suggest no major safety issues with rATG in DCD LTx. Our study should ease clinical apprehension surrounding rATG use for this indication. Future prospective studies are needed to further evaluate the role of rATG and its impact on efficacy end points.

Increased transfusion-free survival following auxiliary pig liver xenotransplantation

BACKGROUND

Pig to baboon liver xenotransplantation typically results in severe thrombocytopenia and coagulation disturbances, culminating in death from hemorrhage within 9 days, in spite of continuous transfusions. We studied the contribution of anticoagulant production and clotting pathway deficiencies to fatal bleeding in baboon recipients of porcine livers.

METHODS

By transplanting liver xenografts from α1,3-galactosyltransferase gene-knockout (GalT-KO) miniature swine donors into baboons as auxiliary organs, leaving the native liver in place, we provided the full spectrum of primate clotting factors and allowed in vivo mixing of porcine and primate coagulation systems.

RESULTS

Recipients of auxiliary liver xenografts develop severe thrombocytopenia, comparable to recipients of conventional orthotopic liver xenografts and consistent with hepatic xenograft sequestration. However, baboons with both pig and native livers do not exhibit clinical signs of bleeding and maintain stable blood counts without transfusion for up to 8 consecutive days post-transplantation. Instead, recipients of auxiliary liver xenografts undergo graft failure or die of sepsis, associated with thrombotic microangiopathy in the xenograft, but not the native liver.

CONCLUSION

Our data indicate that massive hemorrhage in the setting of liver xenotransplantation might be avoided by supplementation with primate clotting components. However, coagulation competent hepatic xenograft recipients may be predisposed to graft loss related to small vessel thrombosis and ischemic necrosis.

Antibody induction versus placebo, no induction, or another type of antibody induction for liver transplant recipients

BACKGROUND

Liver transplantation is an established treatment option for end-stage liver failure. To date, no consensus has been reached on the use of immunosuppressive T-cell antibody induction for preventing rejection after liver transplantation.

OBJECTIVES

To assess the benefits and harms of immunosuppressive T-cell specific antibody induction compared with placebo, no induction, or another type of T-cell specific antibody induction for prevention of acute rejection in liver transplant recipients.

SEARCH METHODS

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Science Citation Index Expanded, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) until September 2013.

SELECTION CRITERIA

Randomised clinical trials assessing immunosuppression with T-cell specific antibody induction compared with placebo, no induction, or another type of antibody induction in liver transplant recipients. Our inclusion criteria stated that participants within each included trial should have received the same maintenance immunosuppressive therapy. We planned to include trials with all of the different types of T-cell specific antibodies that are or have been used for induction (ie., polyclonal antibodies (rabbit of horse antithymocyte globulin (ATG), or antilymphocyte globulin (ALG)), monoclonal antibodies (muromonab-CD3, anti-CD2, or alemtuzumab), and interleukin-2 receptor antagonists (daclizumab, basiliximab, BT563, or Lo-Tact-1)).

DATA COLLECTION AND ANALYSIS

We used RevMan analysis for statistical analysis of dichotomous data with risk ratio (RR) and of continuous data with mean difference (MD), both with 95% confidence intervals (CIs). We assessed the risk of systematic errors (bias) using bias risk domains with definitions. We used trial sequential analysis to control for random errors (play of chance). We presented outcome results in a summary of findings table.

MAIN RESULTS

We included 19 randomised clinical trials with a total of 2067 liver transplant recipients. All 19 trials were with high risk of bias. Of the 19 trials, 16 trials were two-arm trials, and three trials were three-arm trials. Hence, we found 25 trial comparisons with antibody induction agents: interleukin-2 receptor antagonist (IL-2 RA) versus no induction (10 trials with 1454 participants); monoclonal antibody versus no induction (five trials with 398 participants); polyclonal antibody versus no induction (three trials with 145 participants); IL-2 RA versus monoclonal antibody (one trial with 87 participants); and IL-2 RA versus polyclonal antibody (two trials with 112 participants). Thus, we were able to compare T-cell specific antibody induction versus no induction (17 trials with a total of 1955 participants). Overall, no difference in mortality (RR 0.91; 95% CI 0.64 to 1.28; low-quality of evidence), graft loss including death (RR 0.92; 95% CI 0.71 to 1.19; low-quality of evidence), and adverse events ((RR 0.97; 95% CI 0.93 to 1.02; low-quality evidence) outcomes was observed between any kind of T-cell specific antibody induction compared with no induction when the T-cell specific antibody induction agents were analysed together or separately. Acute rejection seemed to be reduced when any kind of T-cell specific antibody induction was compared with no induction (RR 0.85, 95% CI 0.75 to 0.96; moderate-quality evidence), and when trial sequential analysis was applied, the trial sequential monitoring boundary for benefit was crossed before the required information size was obtained. Furthermore, serum creatinine was statistically significantly higher when T-cell specific antibody induction was compared with no induction (MD 3.77 μmol/L, 95% CI 0.33 to 7.21; low-quality evidence), as well as when polyclonal T-cell specific antibody induction was compared with no induction, but this small difference was not clinically significant. We found no statistically significant differences for any of the remaining predefined outcomes - infection, cytomegalovirus infection, hepatitis C recurrence, malignancy, post-transplant lymphoproliferative disease, renal failure requiring dialysis, hyperlipidaemia, diabetes mellitus, and hypertension - when the T-cell specific antibody induction agents were analysed together or separately. Limited data were available for meta-analysis on drug-specific adverse events such as haematological adverse events for antithymocyte globulin. No data were found on quality of life.When T-cell specific antibody induction agents were compared with another type of antibody induction, no statistically significant differences were found for mortality, graft loss, and acute rejection for the separate analyses. When interleukin-2 receptor antagonists were compared with polyclonal T-cell specific antibody induction, drug-related adverse events were less common among participants treated with interleukin-2 receptor antagonists (RR 0.23, 95% CI 0.09 to 0.63; low-quality evidence), but this was caused by the results from one trial, and trial sequential analysis could not exclude random errors. We found no statistically significant differences for any of the remaining predefined outcomes: infection, cytomegalovirus infection, hepatitis C recurrence, malignancy, post-transplant lymphoproliferative disease, renal failure requiring dialysis, hyperlipidaemia, diabetes mellitus, and hypertension. No data were found on quality of life.

AUTHORS' CONCLUSIONS

The effects of T-cell antibody induction remain uncertain because of the high risk of bias of the randomised clinical trials, the small number of randomised clinical trials reported, and the limited numbers of participants and outcomes in the trials. T-cell specific antibody induction seems to reduce acute rejection when compared with no induction. No other clear benefits or harms were associated with the use of any kind of T-cell specific antibody induction compared with no induction, or when compared with another type of T-cell specific antibody. Hence, more randomised clinical trials are needed to assess the benefits and harms of T-cell specific antibody induction compared with placebo, and compared with another type of antibody, for prevention of rejection in liver transplant recipients. Such trials ought to be conducted with low risks of systematic error (bias) and low risk of random error (play of chance).

Antibody induction versus corticosteroid induction for liver transplant recipients

BACKGROUND

Liver transplantation is an established treatment option for end-stage liver failure. To date, no consensus has been reached on the use of immunosuppressive T-cell specific antibody induction compared with corticosteroid induction of immunosuppression after liver transplantation.

OBJECTIVES

To assess the benefits and harms of T-cell specific antibody induction versus corticosteroid induction for prevention of acute rejection in liver transplant recipients.

SEARCH METHODS

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Science Citation Index Expanded, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) on 30 September 2013 together with reference checking, citation searching, contact with trial authors and pharmaceutical companies to identify additional trials.

SELECTION CRITERIA

We included all randomised clinical trials assessing immunosuppression with T-cell specific antibody induction versus corticosteroid induction in liver transplant recipients. Our inclusion criteria stated that participants within each included trial should have received the same maintenance immunosuppressive therapy.

DATA COLLECTION AND ANALYSIS

We used RevMan for statistical analysis of dichotomous data with risk ratio (RR) and of continuous data with mean difference (MD), both with 95% confidence intervals (CIs). We assessed risk of systematic errors (bias) using bias risk domains with definitions. We used trial sequential analysis to control for random errors (play of chance).

MAIN RESULTS

We included 10 randomised trials with a total of 1589 liver transplant recipients, which studied the use of T-cell specific antibody induction versus corticosteroid induction. All trials were with high risk of bias. We compared any kind of T-cell specific antibody induction versus corticosteroid induction in 10 trials with 1589 participants, including interleukin-2 receptor antagonist induction versus corticosteroid induction in nine trials with 1470 participants, and polyclonal T-cell specific antibody induction versus corticosteroid induction in one trial with 119 participants.Our analyses showed no significant differences regarding mortality (RR 1.01, 95% CI 0.72 to 1.43), graft loss (RR 1.12, 95% CI 0.82 to 1.53) and acute rejection (RR 0.84, 95% CI 0.70 to 1.00), infection (RR 0.96, 95% CI 0.85 to 1.09), hepatitis C virus recurrence (RR 0.89, 95% CI 0.79 to 1.00), malignancy (RR 0.59, 95% CI 0.13 to 2.73), and post-transplantation lymphoproliferative disorder (RR 1.00, 95% CI 0.07 to 15.38) when any kind of T-cell specific antibody induction was compared with corticosteroid induction (all low-quality evidence). Cytomegalovirus infection was less frequent in patients receiving any kind of T-cell specific antibody induction compared with corticosteroid induction (RR 0.50, 95% CI 0.33 to 0.75; low-quality evidence). This was also observed when interleukin-2 receptor antagonist induction was compared with corticosteroid induction (RR 0.55, 95% CI 0.37 to 0.83; low-quality evidence), and when polyclonal T-cell specific antibody induction was compared with corticosteroid induction (RR 0.21, 95% CI 0.06 to 0.70; low-quality evidence). However, when trial sequential analysis regarding cytomegalovirus infection was applied, the required information size was not reached. Furthermore, diabetes mellitus occurred less frequently when T-cell specific antibody induction was compared with corticosteroid induction (RR 0.45, 95% CI 0.34 to 0.60; low-quality evidence), when interleukin-2 receptor antagonist induction was compared with corticosteroid induction (RR 0.45, 95% CI 0.35 to 0.61; low-quality evidence), and when polyclonal T-cell specific antibody induction was compared with corticosteroid induction (RR 0.12, 95% CI 0.02 to 0.95; low-quality evidence). When trial sequential analysis was applied, the trial sequential monitoring boundary for benefit was crossed. We found no subgroup differences for type of interleukin-2 receptor antagonist (basiliximab versus daclizumab). Four trials reported on adverse events. However, no differences between trial groups were noted. Limited data were available for meta-analysis on drug-specific adverse events such as haematological adverse events for antithymocyte globulin. No data were available on quality of life.

AUTHORS' CONCLUSIONS

Because of the low quality of the evidence, the effects of T-cell antibody induction remain uncertain. T-cell specific antibody induction seems to reduce diabetes mellitus and may reduce cytomegalovirus infection when compared with corticosteroid induction. No other clear benefits or harms were associated with the use of T-cell specific antibody induction compared with corticosteroid induction. For some analyses, the number of trials investigating the use of T-cell specific antibody induction after liver transplantation is small, and the numbers of participants and outcomes in these randomised trials are limited. Furthermore, the included trials are heterogeneous in nature and have applied different types of T-cell specific antibody induction therapy. All trials were at high risk of bias. Hence, additional randomised clinical trials are needed to assess the benefits and harms of T-cell specific antibody induction compared with corticosteroid induction for liver transplant recipients. Such trials ought to be conducted with low risks of systematic error and of random error.

Peritransplant absolute lymphocyte count as a predictive factor for advanced recurrence of hepatitis C after liver transplantation

Lymphocytes play an active role in natural immunity against hepatitis C virus (HCV). We hypothesized that a lower absolute lymphocyte count (ALC) may alter HCV outcome after liver transplantation (LT). The aim of this study was to investigate the impact of peritransplant ALC on HCV recurrence following LT. A total of 289 LT patients between 2005 and 2011 were evaluated. Peritransplant ALC (pre-LT, 2-week, and 1-month post-LT) and immunosuppression were analyzed along with recipient and donor factors in order to determine risk factors for HCV recurrence based on METAVIR fibrosis score. When stratifying patients according to pre- and post-LT ALC (<500/μL versus 500-1,000/μL versus >1,000/μL), lymphopenia was significantly associated with higher rates of HCV recurrence with fibrosis (F2-4). Multivariate Cox regression analysis showed posttransplant ALC at 1 month remained an independent predictive factor for recurrence (P = 0.02, hazard ratio [HR] = 2.47 for <500/μL). When peritransplant ALC was persistently low (<500/μL pre-LT, 2-week, and 1-month post-LT), patients were at significant risk of developing early advanced fibrosis secondary to HCV recurrence (F3-4 within 2 years) (P = 0.02, HR = 3.16). Furthermore, severe pretransplant lymphopenia (<500/μL) was an independent prognostic factor for overall survival (P = 0.01, HR = 3.01). The use of rabbit anti-thymocyte globulin induction (RATG) had a remarkable protective effect on HCV recurrence (P = 0.02, HR = 0.6) despite its potential to induce lymphopenia. Subgroup analysis indicated that negative effects of posttransplant lymphopenia at 1 month (<1,000/μL) were significant regardless of RATG use and the protective effects of RATG were independent of posttransplant lymphopenia.

CONCLUSION

Peritransplant ALC is a novel and useful surrogate marker for prediction of HCV recurrence and patient survival. Immunosuppression protocols and peritransplant management should be scrutinized depending on peritransplant ALC.

Intestinal and multivisceral transplantation immunosuppression protocols--literature review

INTRODUCTION

Currently the most used techniques for small bowel transplant are isolated intestinal transplantation, multivisceral transplantation (MVT), and modified multivisceral transplantation. One important factor is early diagnosis of acute cellular rejection (ACR). In addition, improvements in immunosuppression have recently reduced the number and enhanced treatment of ACR episodes, enabling graft recovery.

OBJECTIVE

We analyzed immunosuppression protocols of leading transplantation centers in the last 5 years.

METHOD

We reviewed papers published in PubMed from major multivisceral and intestinal transplantation centers from 2006 to 2010 in adult recipients. The 211 adults transplanted in seven centers were divided into three groups according to the immunosuppression protocol used: protocol 1: daclizumab induction with tacrolimus and steroid maintenance; protocol 2: alemtuzumab and tacrolimus; and protocol 3: thymoglobulin and rituximab and tacrolimus.

RESULTS

Protocol 2 showed the lowest rate of ACR (34%). Protocols 1 and 3 displayed 54% and 48% ACR rates; respectively. However, protocol 1 patients developed only mild ACR, whereas those in protocols 2 and 3 developed moderate ACR in 26.3% and 11.7%, and severe ACR in 7.9% and 47% of cases, respectively. The infection rate was considerably lower in protocol 3 (7.4%). Protocols 1 and 2 showed infection rates of 62.5% and 52%, respectively. One-year patient survival rates were 70%, 79% and 81%, respectively. Three-year patient survival rates were 62%, 56%, and 78% for protocols 1, 2 and 3, respectively.

CONCLUSION

Protocol 2 was the strongest immunosuppressive regimen capable of reducing ACR rates when compared with the other protocols, but the strong effect resulted in high infection rate that impacts 1-year patient survival. Protocol 3 seems to be the best available one balancing ACR and infection rates.

Current protective strategies in liver surgery

During liver resection surgery for cancer or liver transplantation, the liver is subject to ischaemia (reduction in blood flow) followed by reperfusion (restoration of blood flow), which results in liver injury [ischemia-reperfusion (IR) or IR injury]. Modulation of IR injury can be achieved in various ways. These include hypothermia, ischaemic preconditioning (IPC) (brief cycles of ischaemia followed by reperfusion of the organ before the prolonged period of ischaemia i.e. a conditioning response), ischaemic postconditioning (conditioning after the prolonged period of ischaemia but before the reperfusion), pharmacological agents to decrease IR injury, genetic modulation of IR injury, and machine perfusion (pulsatile perfusion). Hypothermia decreases the metabolic functions and the oxygen consumption of organs. Static cold storage in University of Wisconsin solution reduces IR injury and has prolonged organ storage and improved the function of transplanted grafts. There is currently no evidence for any clinical advantage in the use of alternate solutions for static cold storage. Although experimental data from animal models suggest that IPC, ischaemic postconditioning, various pharmacological agents, gene therapy, and machine perfusion decrease IR injury, none of these interventions can be recommended in clinical practice. This is because of the lack of randomized controlled trials assessing the safety and efficacy of ischaemic postconditioning, gene therapy, and machine perfusion. Randomized controlled trials and systematic reviews of randomized controlled trials assessing the safety and efficacy of IPC and various pharmacological agents have demonstrated biochemical or histological improvements but this has not translated to clinical benefit. Further well designed randomized controlled trials are necessary to assess the various new protective strategies in liver resection.

The effect of murine anti-thymocyte globulin on experimental kidney warm ischemia-reperfusion injury in mice

Kidney ischemia-reperfusion injury (IRI) is an important contributor to delayed graft function (DGF) and poor outcome of allografts. Small clinical studies suggest a beneficial role for human anti-thymocyte globulin (ATG) in DGF. We investigated the short-term effect of mouse anti-thymocyte globulin (mATG) on kidney warm IRI in mice. We administered either mATG, rabbit immunoglobulin (RIgG), or saline with different dosing schedules in three different IRI models: 30 min bilateral, 60 min bilateral, and 45min unilateral IRI. mATG effectively depleted circulating T cells but had less effect on kidney-infiltrating T cells. There was no difference in serum creatinine levels between groups in each study. Scoring of renal tubular damage and regenerating tubules revealed no difference between groups. The percentage of CD3(+)CD4(-)CD8(-) double-negative (DN) T cells, which were reported to contribute to the pathogenesis of lupus nephritis, increased and the percentages of regulatory T cells and NK cells decreased in the post-ischemic kidneys of mATG treated mice. mATG did not alter the expression of pro-inflammatory cytokines such as IFN-gamma or anti-inflammatory cytokines such as IL-10 in post-ischemic kidneys. mATG treatment, whether initiated before ischemia or immediately after reperfusion, had minimal effects on renal injury following warm IRI in mice.

Induction immunosuppression with thymoglobulin and rituximab in intestinal and multivisceral transplantation

BACKGROUND

Induction immunosuppression is now a common practice after intestinal and multivisceral transplantation. We report our experience in 27 adult recipients who received rituximab and rabbit antithymocyte globulin (rATG) in combination as induction agents.

MATERIAL AND METHODS

Twenty-seven adult patients received 29 intestinal transplants between July 2004 and March 2007. All patients received induction immunosuppression therapy with rATG, rituximab, and steroids. Tacrolimums and a steroid taper were used for maintenance therapy. Patient and graft survival, episodes of rejection as well as posttransplant lymphoproliferative disease (PTLD) and graft-versus-host disease were analyzed.

RESULTS

One-year patient and graft survival was 81% and 76%, respectively. Thirteen patients (48%) experienced 19 episodes of acute rejection (9 mild episodes, 2 moderate, and 8 severe). Patients with a multivisceral graft experienced less episodes of severe acute rejection (1 of 19, 5%) when compared with isolated intestinal transplants and modified multivisceral transplants (7 of 10, 70%). Two patients had episodes of skin graft-versus-host disease that responded to steroid boluses. PTLD was not seen in our series. Two patients developed cytomegalovirus enteritis.

CONCLUSIONS

The combination of rATG and rituximab was an effective induction therapy in our preliminary data. The number and severity of rejection episodes increased when the liver was not included as part of the graft. An immunosuppression regimen including rATG, rituximab, and steroids may have a protective effect against PTLD and chronic rejection.