Long-term outcome of human leukocyte antigen mismatching in liver transplantation: results of the National Institute of Diabetes and Digestive and Kidney Diseases Liver Transplantation Database

Autoimmune hepatitis recurrence after liver transplantation: "Les jeux sont faits"

Autoimmune hepatitis (AIH) may recur after liver transplantation (LT). The aims of this study were to evaluate the incidence and risk factors for recurrent autoimmune hepatitis (rAIH). A multicenter retrospective French nationwide study, including all patients aged ≥16 transplanted for AIH, with at least 1 liver biopsy 1 year after LT, was conducted between 1985 and 2018. Risk factors for rAIH were identified using a multivariate Cox regression model. Three hundred and forty-four patients were included (78.8% women) with a median age at LT of 43.6 years. Seventy-six patients (22.1%) developed recurrence in a median time of 53.6 months (IQR, 14.1-93.2). Actuarial risk for developing rAIH was 41.3% 20 years after LT. In multivariate analysis, the strongest risk factor for rAIH was cytomegalovirus D+/R- mismatch status (HR=2.0; 95% CI: 1.1-3.6; p =0.03), followed by associated autoimmune condition. Twenty-one patients (27.6% of rAIH patients) developed liver graft cirrhosis after rAIH. Independent risk factors for these severe forms of rAIH were young age at LT, IgG levels >20.7 g/L, and LT in the context of (sub)fulminant hepatitis. Immunosuppression, especially long-term maintenance of corticosteroid therapy, was not significantly associated with rAIH. Recurrence of AIH after LT is frequent and may lead to graft loss. Recurrence is more frequent in young patients with active disease at the time of LT, yet systematic corticosteroid therapy does not prevent it.

Immunology demystified: A guide for transplant hepatologists

Liver transplantation has become standard practice for treating end-stage liver disease. The success of the procedure relies on effective immunosuppressive medications to control the host's immune response. Despite the liver's inherent capacity to foster tolerance, the early post-transplant period is marked by significant immune reactivity. To ensure favorable outcomes, it is imperative to identify and manage various rejection types, encompassing T-cell-mediated, antibody-mediated, and chronic rejection. However, the approach to prescribing immunosuppressants relies heavily on clinical judgment rather than evidence-based criteria. Given that the majority of patients will require lifelong immuno suppression as the mechanisms underlying operational tolerance are still being investigated, healthcare providers must possess an understanding of immune responses, rejection mechanisms, and the pathways targeted by immunosuppressive drugs. This knowledge enables customization of treatments and improved patient care, even though a consensus on an optimal immunosuppressive regimen remains elusive.

HLA matching between donors and recipients improves clinical liver transplant graft survival

BACKGROUND AND AIMS

The importance of human leukocyte antigen (HLA) matching between liver transplant donors and recipients on graft survival remains unclear and is not a clinical consideration in liver transplantation. This study aimed to determine the relationship between HLA matching and liver graft survival using a large-scale multi-centre database (UNOS/OPTN) and multivariate logistic analysis. The secondary aim was to determine whether this relationship was influenced by transplant indication and donor status.

METHODS

This retrospective observational analysis was performed using 22 702 liver transplant recipients from the UNOS/OPTN database. Patients were divided into two groups based on number of HLA mismatches (0-3 mismatches vs. 4-6 mismatches) and then subcategorized by indication and donor status. Risk-adjusted outcomes were assessed by multivariate Cox analysis adjusting for donor and recipient characteristics and visualized using Kaplan-Meier survival curves.

RESULTS

Allograft survival and risk of acute rejection were associated with degree of HLA mismatch. This association between HLA mismatch and graft survival persisted in individuals who underwent transplant for hepatitis, metabolic, drug toxicity, and congenital indications. Donor status also influenced the relationship between HLA mismatch and graft survival. Graft survival in DBD recipients was longer than in DCD in the 4-6 HLA mismatch group, whereas no significant difference was found in the 0-3 HLA mismatch group.

CONCLUSION

HLA mismatch significantly reduced graft survival and increased risk of acute rejection. This association was noted only in specific indications. These findings are of potential clinical relevance to organ allocation, allograft matching algorithms, immunosuppression protocols, and transplant surveillance.

Post-Transplant Management and Complications of Autoimmune Hepatitis, Primary Biliary Cholangitis, and Primary Sclerosing Cholangitis including Disease Recurrence

Autoimmune liver diseases have unique post-transplant considerations. These recipients are at increased risk of rejection, and recurrent disease may also develop, which can progress to graft loss and increase mortality. Monitoring for and managing these complications is therefore important, though data on associated risk factors and immunosuppression strategies has in most cases been mixed. There are also other disease-specific complications that require management and may impact these decisions, including inflammatory bowel disease in PSC. Further work to better understand the optimal management strategies for these patients post-transplant is needed.

Cyclosporine vs. tacrolimus after liver transplantation for primary sclerosing cholangitis - a propensity score-matched intention-to-treat analysis

BACKGROUND & AIMS

There is controversy regarding the optimal calcineurin inhibitor type after liver transplant(ation) (LT) for primary sclerosing cholangitis (PSC). We compared tacrolimus with cyclosporine in a propensity score-matched intention-to-treat analysis based on registries representing nearly all LTs in Europe and the US.

METHODS

From the European Liver Transplant Registry (ELTR) and Scientific Registry of Transplant Recipients (SRTR), we included adult patients with PSC undergoing a primary LT between 2000-2020. Patients initially treated with cyclosporine were propensity score-matched 1:3 with those initially treated with tacrolimus. The primary outcomes were patient and graft survival rates.

RESULTS

The propensity score-matched sample comprised 399 cyclosporine-treated and 1,197 tacrolimus-treated patients with PSC. During a median follow-up of 7.4 years (IQR 2.3-12.8, 12,579.2 person-years), there were 480 deaths and 231 re-LTs. The initial tacrolimus treatment was superior to cyclosporine in terms of patient and graft survival, with 10-year patient survival estimates of 72.8% for tacrolimus and 65.2% for cyclosporine (p <0.001) and 10-year graft survival estimates of 62.4% and 53.8% (p <0.001), respectively. These findings were consistent in the subgroups according to age, sex, registry (ELTR vs. SRTR), time period of LT, MELD score, and diabetes status. The acute rejection rates were similar between groups. In the multivariable Cox regression analysis, tacrolimus (hazard ratio 0.72, p <0.001) and mycophenolate use (hazard ratio 0.82, p = 0.03) were associated with a reduced risk of graft loss or death, whereas steroid use was not significant.

CONCLUSIONS

Tacrolimus is associated with better patient and graft survival rates than cyclosporine and should be the standard calcineurin inhibitor used after LT for patients with PSC.

IMPACT AND IMPLICATIONS

The optimal calcineurin inhibitor to use after liver transplantation in patients with primary sclerosing cholangitis has yet to be firmly established. Since randomized trials with long follow-up are unlikely to be performed, multicontinental long-term registry data are essential in informing clinical practices. Our study supports the practice of using tacrolimus instead of cyclosporine in the initial immunosuppressive regimen after liver transplantation for patients with primary sclerosing cholangitis. The retrospective registry-based design is a limitation.

The Effect of Genetic HLA Matching on Liver Transplantation Outcome: A Systematic Review and Meta-Analysis

Objective

We aim to investigate the effects of genetically based HLA matching on patient and graft survival, and acute and chronic rejection after liver transplantation.

Background

Liver transplantation is a common treatment for patients with end-stage liver disease. In contrast to most other solid organ transplantations, there is no conclusive evidence supporting human leukocyte antigen (HLA) matching for liver transplantations. With emerging alternatives such as transplantation of bankable (stem) cells, HLA matching becomes feasible, which may decrease the need for immunosuppressive therapy and improve transplantation outcomes.

Methods

We systematically searched the PubMed, Embase, and Cochrane databases and performed a meta-analysis investigating the effect of genetic HLA matching on liver transplantation outcomes (acute/chronic rejection, graft failure, and mortality).

Results

We included 14 studies with 2682 patients. HLA-C mismatching significantly increased the risk of acute rejection (full mismatching: risk ratio = 1.90, 95% confidence interval = 1.08 to 3.33, P = 0.03; partial mismatching: risk ratio = 1.33, 95% confidence interval = 1.07 to 1.66, P = 0.01). We did not discern any significant effect of HLA mismatching per locus on acute rejection for HLA-A, -B, -DR, and -DQ, nor on chronic rejection, graft failure, or mortality for HLA-DR, and -DQ.

Conclusions

We found evidence that genetic HLA-C matching reduces the risk of acute rejection after liver transplantation while matching for other loci does not reduce the risk of acute rejection, chronic rejection, graft failure, or mortality.

Post-Transplant Immunosuppression in Autoimmune Liver Disease

Autoimmune liver diseases (AILDs) are a group of conditions where immune-mediated liver damage can lead to the need for transplantation. Collectively, they account for almost a quarter of all liver transplants. Outcomes in terms of graft and patient survival for all liver transplants have improved markedly over decades with improvements in patient selection, surgical techniques and longer-term care and this is also seen in patients with AILDs. The current five- and ten-year survival rates post-transplant in autoimmune disease are excellent, at 88% and 78%, respectively. A key factor in maintaining good outcomes post liver transplant for these autoimmune conditions is the immunosuppression strategy. These patients have increased the rates of rejection, and autoimmune conditions can all recur in the graft ranging from 12 to 60% depending on the population studied. Immunosuppressive regimens are centred on calcineurin inhibitors, often combined with low dose corticosteroids, with or without the addition of antimetabolite therapy. There is no clear evidence-based immunosuppressive regimen for these conditions, and a tailored approach balancing the individuals' immunological profile against the risks of immunosuppression is often used. There are disease-specific considerations to optimised graft function including the role of ursodeoxycholic acid in both primary biliary cholangitis and primary sclerosing cholangitis and the role and timing of colectomy in primary sclerosing cholangitis in inflammatory bowel disease patients. However, unmet needs still exist in the management of AILDs post liver transplantation particularly in building the evidence base for optimal immunosuppression as well as mitigating the risk of recurrent disease.

The impact of human leukocyte antigen mismatch on recipient outcomes in living-donor liver transplantation

Donor-recipient human leukocyte antigen (HLA) compatibility has not been considered to significantly affect liver transplantation (LT) outcomes; however, its significance in living-donor LT (LDLT), which is mostly performed between blood relatives, remains unclear. This retrospective cohort study included 1954 LDLTs at our institution (1990-2020). The primary and secondary endpoints were recipient survival and the incidence of T cell-mediated rejection (TCMR) after LDLT, respectively, according to the number of HLA mismatches at all five loci: HLA-A, HLA-B, HLA-C, HLA-DR, and HLA-DQ. Subgroup analyses were also performed in between-siblings that characteristically have widely distributed 0-10 HLA mismatches. A total of 1304 cases of primary LDLTs were finally enrolled, including 631 adults (recipient age at LT ≥18 years) and 673 children (<18 years). In adult-to-adult LDLT, the more HLA mismatches at each locus, the significantly worse the recipient survival was (p = 0.03, 0.01, 0.03, 0.001, and <0.001 for HLA-A, HLA-B, HLA-C, HLA-DR, and HLA-DQ, respectively). This trend was more pronounced when multiple loci were combined (all p < 0.001 for A + B + DR, A + B + C, DR + DQ, and A + B + C + DR + DQ). Notably, a total of three or more HLA-B + DR mismatches was an independent risk factor for both TCMR (hazard ratio [HR] 2.66, 95% confidence interval [CI] 1.21-5.87; p = 0.02) and recipient survival (HR 2.44, 95% CI 1.11-5.35; p = 0.03) in between-siblings. By contrast, HLA mismatch did not affect pediatric LDLT outcomes at any locus or in any combinations; however, it should be noted that all donor-recipient relationships are parent-to-child that characteristically possesses one or less HLA mismatch at each locus and maximally five or less mismatches in total. In conclusion, HLA mismatch significantly affects not only TCMR development but also recipient survival in adult LDLT, but not in children.

Donor-recipient human leukocyte antigen A mismatching is associated with hepatic artery thrombosis, sepsis, graft loss, and reduced survival after liver transplant

Human leukocyte antigen (HLA) matching is not routinely performed for liver transplantation as there is no consistent evidence of benefit; however, the impact of HLA mismatching remains uncertain. We explored the effect of class I and II HLA mismatching on graft failure and mortality. A total of 1042 liver transplants performed at a single center between 1999 and 2016 with available HLA typing data were included. The median follow-up period was 9.38 years (interquartile range 4.9-14) and 350/1042 (33.6%) transplants resulted in graft loss and 280/1042 (26.9%) in death. Graft loss and mortality were not associated with the overall number of mismatches at HLA-A, HLA-B, HLA-C, HLA-DR, and HLA-DQ loci. However, graft failure and mortality were both increased in HLA mismatching on graft failure and mortality the presence of one (p = 0.004 and p = 0.01, respectively) and two (p = 0.01 and p = 0.04, respectively) HLA-A mismatches. Elevated hazard ratios for graft failure and death were observed with HLA-A mismatches in univariate and multivariate Cox proportional hazard models. Excess graft loss with HLA-A mismatch (138/940 [14.7%] mismatched compared with 6/102 [5.9%] matched transplants) occurred within the first year following transplantation (odds ratio 2.75; p = 0.02). Strikingly, transplants performed at a single all grafts lost due to hepatic artery thrombosis were in HLA-A-mismatched transplants (31/940 vs. 0/102), as were those lost due to sepsis (35/940 vs. 0/102). In conclusion, HLA-A mismatching was associated with increased graft loss and mortality. The poorer outcome for the HLA-mismatched group was due to hepatic artery thrombosis and sepsis, and these complications occurred exclusively with HLA-A-mismatched transplants. These data suggest that HLA-A mismatching is important for outcomes following liver transplant. Therefore, knowledge of HLA-A matching status may potentially allow for enhanced surveillance, clinical interventions in high-risk transplants or stratified HLA-A matching in high-risk recipients.

Assessment of human leukocyte antigen matching algorithm PIRCHE-II on liver transplantation outcomes

For liver transplantations, human leukocyte antigen (HLA) matching is not routinely performed because observed effects have been inconsistent. Nevertheless, long-term liver transplantation outcomes remain suboptimal. The availability of a more precise HLA-matching algorithm, Predicted Indirectly Recognizable HLA Epitopes II (PIRCHE-II), now enables robust assessment of the association between HLA matching and liver transplantation outcomes. We performed a single-center retrospective cohort study of 736 liver transplantation patients. Associations between PIRCHE-II and HLAMatchmaker scores and mortality, graft loss, acute and chronic rejection, ischemic cholangiopathy, and disease recurrence were evaluated with Cox proportional hazards models. Associations between PIRCHE-II with 1-year, 2-year, and 5-year outcomes and severity of acute rejection were assessed with logistic and linear regression analyses, respectively. Subgroup analyses were performed for autoimmune and nonautoimmune indications, and patients aged 30 years and younger, and older than 30 years. PIRCHE-II and HLAMatchmaker scores were not associated with any of the outcomes. However, patients who received transplants for autoimmune disease showed more acute rejection and graft loss, and these risks negatively associated with age. Rhesus mismatch more than doubled the risk of disease recurrence. Moreover, PIRCHE-II was inversely associated with graft loss in the subgroup of patients aged 30 years and younger with autoimmune indications. The absence of associations between PIRCHE-II and HLAMatchmaker scores and the studied outcomes refutes the need for HLA matching for liver (stem cell) transplantations for nonautoimmune disease. For autoimmune disease, the activated immune system seems to increase risks of acute rejection and graft loss. Our results may suggest the benefits of transplantations with rhesus matched but PIRCHE-II mismatched donor livers.

Human Hepatic CD56bright NK Cells Display a Tissue-Resident Transcriptional Profile and Enhanced Ability to Kill Allogenic CD8+ T Cells

Liver-resident CD56^brightCD16^- natural killer (NK) cells are enriched in the human liver and are phenotypically distinct from their blood counterparts. Although these cells are capable of rapid cytotoxic effector activity, their functional role remains unclear. We hypothesise that they may contribute to immune tolerance in the liver during transplantation. RNA sequencing was carried out on FACS sorted NK cell subpopulations from liver perfusates (n=5) and healthy blood controls (n=5). Liver-resident CD56^brightCD16^+/- NK cells upregulate genes associated with tissue residency. They also upregulate expression of CD160 and LY9, both of which encode immune receptors capable of activating NK cells. Co-expression of CD160 and Ly9 on liver-resident NK cells was validated using flow cytometry. Hepatic NK cell cytotoxicity against allogenic T cells was tested using an in vitro co-culture system of liver perfusate-derived NK cells and blood T cells (n=10-13). In co-culture experiments, hepatic NK cells but not blood NK cells induced significant allogenic T cell death (p=0.0306). Allogenic CD8⁺ T cells were more susceptible to hepatic NK cytotoxicity than CD4⁺ T cells (p<0.0001). Stimulation of hepatic CD56^bright NK cells with an anti-CD160 agonist mAb enhanced this cytotoxic response (p=0.0382). Our results highlight a role for donor liver NK cells in regulating allogenic CD8⁺ T cell activation, which may be important in controlling recipient CD8⁺ T cell-mediated rejection post liver-transplant.

Association of human leukocyte antigen mismatches between donor-recipient and donor-donor in pancreas after kidney transplant recipients

The effects of HLA mismatching on pancreas outcomes among pancreas after kidney (PAK) recipients are undefined. Outcomes might potentially differ depending on whether there is a mismatch between pancreas donor and recipient (PD-R) or pancreas donor and kidney donor(PD-KD). All primary PAK at our centre were included in this study. Patients were divided into two groups based on the degree of HLA mismatching: low (L-MM) as 0-4 and high (H-MM) as 5-6. We analysed all (N = 73) PAK for PD-R mismatch and the subset of PAK for PD-KD mismatch (N = 71). Comparing PD-R L-MM (n = 39) and H-MM (n = 34) PAKs, we observed no difference in the rate of pancreas graft failure. There was also no difference in the rate of rejection (L-MM 33% vs. H-MM 41%) or the severity of rejection. However, we observed a significantly (P < 0.01) shorter time to acute pancreas rejection in the H-MM group (6.8 ± 8.7 mo) versus the L-MM cohort (29.0 ± 36.2 mo) (P < 0.001). Similar to the PD-R mismatched cohort, we did not observe a detrimental effect of HLA mismatching on graft outcomes in the PD-KD cohort; time to rejection was again shorter in the H-MM subset. In this study, we found no impact of HLA mismatch on either pancreas graft survival or rejection rates, though rejection occurred earlier in high mismatched PAK transplants.

'As a surgeon, I am obliged to every single patient': evaluation of focus group discussions with transplantation physicians on the allocation of donor organs

INTRODUCTION

Organ transplantation is the last resort for many patients. The ubiquitous shortage of suitable donor organs raises the question of best-justifiable allocation worldwide. This study investigates how physicians would allocate donor organs.

METHODS

Focus group discussions with a total of 12 transplant surgeons and 2 other transplant-related physicians were held at the annual conference of the German Transplantation Society (Oct 2019). Three groups discussed aspects of 'egalitarianism', 'effectiveness/benefit', 'medical urgency', 'own fault', 'medical background' and 'socio-demographic status'.

RESULTS AND DISCUSSION

It was observed that physicians often find themselves confronted with conflicts between (a) trying to advocate for their individual patients versus (b) seeing the systemic perspective and understanding the global impact of their decisions at the same time. The groups agreed that due to the current shortage of donor organs in the German allocation system, transplanted patients are often too sick at the point of transplantation and that a better balance between urgency and effectiveness is needed. The aspects of 'effectiveness' and 'urgency' were identified as the most challenging issues and thus were the main focus of debate. The dilemmas physicians find themselves in become increasingly severe, the larger the shortage of suitable donor organs is.

HLA-DR Mismatch and Black Race Are Associated With Recurrent Autoimmune Hepatitis After Liver Transplantation

Supplemental Digital Content is available in the text.

The predictors of recurrent autoimmune hepatitis (R-AIH) after liver transplantation (LT) are heterogeneous with limited data to guide immunosuppression, with little data on impact of race.

Management of Autoimmune Liver Diseases after Liver Transplantation

Autoimmune liver diseases are characterized by immune-mediated inflammation and eventual destruction of the hepatocytes and the biliary epithelial cells. They can progress to irreversible liver damage requiring liver transplantation. The post-liver transplant goals of treatment include improving the recipient’s survival, preventing liver graft-failure, and decreasing the recurrence of the disease. The keystone in post-liver transplant management for autoimmune liver diseases relies on identifying which would be the most appropriate immunosuppressive maintenance therapy. The combination of a steroid and a calcineurin inhibitor is the current immunosuppressive regimen of choice for autoimmune hepatitis. A gradual withdrawal of glucocorticoids is also recommended. On the other hand, ursodeoxycholic acid should be initiated soon after liver transplant to prevent recurrence and improve graft and patient survival in primary biliary cholangitis recipients. Unlike the previously mentioned autoimmune diseases, there are not immunosuppressive or disease-modifying agents available for patients with primary sclerosing cholangitis. However, colectomy and annual colonoscopy are key components during the post-liver transplant period.

Identification of peripheral CD154+ T cells and HLA-DRB1 as biomarkers of acute cellular rejection in adult liver transplant recipients

Decreasing graft rejection and increasing graft and patient survival are great challenges facing liver transplantation (LT). Different T cell subsets participate in the acute cellular rejection (ACR) of the allograft. Cell-mediated immunity markers of the recipient could help to understand the mechanisms underlying acute rejection. This study aimed to analyse different surface antigens on T cells in a cohort of adult liver patients undergoing LT to determine the influence on ACR using multi-parametric flow cytometry functional assay. Thirty patients were monitored at baseline and during 1 year post-transplant. Two groups were established, with (ACR) and without (NACR) acute cellular rejection. Leukocyte, total lymphocyte, percentages of CD4+ CD154+ and CD8+ CD154+ T cells, human leukocyte antigen (HLA) mismatch between recipient-donor and their relation with ACR as well as the acute rejection frequencies were analysed. T cells were stimulated with concanavalin A (Con-A) and surface antigens were analysed by fluorescence activated cell sorter (FACS) analysis. A high percentage of CD4+ CD154+ T cells (P = 0·001) and a low percentage of CD8+ CD154+ T cells (P = 0·002) at baseline were statistically significant in ACR. A receiver operating characteristic analysis determined the cut-off values capable to stratify patients at high risk of ACR with high sensitivity and specificity for CD4+ CD154+ (P = 0·001) and CD8+ CD154+ T cells (P = 0·002). In logistic regression analysis, CD4+ CD154+ , CD8+ CD154+ and HLA mismatch were confirmed as independent risk factors to ACR. Post-transplant percentages of both T cell subsets were significantly higher in ACR, despite variations compared to pretransplant. These findings support the selection of candidates for LT based on the pretransplant percentages of CD4+ CD154+ and CD8+ CD154+ T cells in parallel with other transplant factors.

Understanding, predicting and achieving liver transplant tolerance: from bench to bedside

In the past 40 years, liver transplantation has evolved from a high-risk procedure to one that offers high success rates for reversal of liver dysfunction and excellent patient and graft survival. The liver is the most tolerogenic of transplanted organs; indeed, immunosuppressive therapy can be completely withdrawn without rejection of the graft in carefully selected, stable long-term liver recipients. However, in other recipients, chronic allograft injury, late graft failure and the adverse effects of anti-rejection therapy remain important obstacles to improved success. The liver has a unique composition of parenchymal and immune cells that regulate innate and adaptive immunity and that can promote antigen-specific tolerance. Although the mechanisms underlying liver transplant tolerance are not well understood, important insights have been gained into how the local microenvironment, hepatic immune cells and specific molecular pathways can promote donor-specific tolerance. These insights provide a basis for the identification of potential clinical biomarkers that might correlate with tolerance or rejection and for the development of novel therapeutic targets. Innovative approaches aimed at promoting immunosuppressive drug minimization or withdrawal include the adoptive transfer of donor-derived or recipient-derived regulatory immune cells to promote liver transplant tolerance. In this Review, we summarize and discuss these developments and their implications for liver transplantation.

HLA class II donor specific antibodies are associated with graft cirrhosis after liver transplant independent of the mean fluorescence intensity level

Background

The importance of donor-specific antibodies (DSA) after liver transplantation (LT) for graft and patient survival is an ongoing controversy. So far it has not been elucidated when and in how far DSA are harmful for graft and patient survival. Therefore, we had the aim to investigate the association of DSA with complications after LT.

Methods

Data of 430 LT recipients were collected and statistically analyzed. Detection of HLA antibodies (Ab) was performed by Luminex assay.

Results

DSA were detected in 81 patients (18.8%). These were mainly HLA class II Ab (81.5%). HLA class II Ab show a higher MFI (median: 5.300) compared to HLA class I Ab (median: 2.300). There is no association between MFI levels and development of complications after LT. However, cirrhosis occurred significantly more often in DSA positive patients (18%) than in patients without detectable DSA (9%, P = 0.027). All DSA positive patients with cirrhosis of the graft showed HLA class II antibodies (OR: 3.028; 95% CI: 1.51–6.075; P = 0.002).

Conclusion

Occurrence of HLA class II DSA after LT is associated with graft cirrhosis and may indicate a higher risk to develop graft damage independent on MFI and requires an individualized risk management.

Autoimmune Hepatitis: 2019 Update

Autoimmune hepatitis (AIH) is a chronic inflammatory liver disease, characterized by the elevation of aminotransferases, presence of anti-nuclear antibody or anti-smooth muscle antibody, elevated immunoglobulin G (IgG), and interface hepatitis/plasma-lymphocytic inflammation based on histology. Recent epidemiological studies have indicated an increasing trend in the prevalence of AIH worldwide, especially in male patients; this trend may suggest the alteration of environmental triggers of disease onset over time. As no disease-specific biomarker or histological finding is currently available, AIH requires a clinical diagnosis, and a validated diagnostic scoring system with acceptable specificity and sensitivity has been proposed. Regarding treatment, corticosteroids and azathioprine are recommended, and in those who exhibit an incomplete response or those who are intolerant to these drugs, second-line therapy, such as mycophenolate mofetil, is considered. Overall, the long-term outcome is excellent in patients with complete biochemical responses, while life-long maintenance treatment may be required since the cessation of immunosuppressive agents frequently leads to the relapse of the disease. Acute-onset AIH does occur, and the diagnosis is very challenging due to the lack of serum autoantibodies or elevated IgG. The unmet needs include earlier diagnosis, intervention with disseminated clinical practice guidelines, and recognition and improvement of patients’ health-related quality of life with the development of novel corticosteroid-free treatment regimens.

Do Recipients of Genetically Related Donors Have Better Outcomes After Living Donor Liver Transplantation?

BACKGROUND

There are few data on genetic relation of the donor and outcomes in living donor liver transplantation (LDLT) recipients. We compared outcomes of LDLT between recipients of genetically related and unrelated donors in a large single-center series.

METHODS

The study included 1372 adult, ABO-compatible, primary LDLT recipients, who received a graft from either a first-degree relative (parent, sibling, son, or daughter; n = 756) or unrelated donor (spouse or relative of the spouse; n = 616).

RESULTS

The mean age of the recipients with a related donor was 50.2 ± 10.8 years compared with 47.3 ± 9.3 years for recipients with unrelated donors (P = 0.000). Chronic rejection was significantly more common in the genetically unrelated donor group than in the genetically related donor group (28 [4.5%] versus 9 [1.1%]; P = 0.000) at a mean follow-up of 37 months (15-95 months). There were no significant differences in other outcomes between the 2 groups. The 12-month and 36-month survival between the unrelated and related groups was 87.6% versus 90%, and 86.3% versus 89.7% respectively (P = 0.115). The multivariate analysis revealed genetically unrelated donors (odds ratio [OR]: 3.88, 95% confidence interval [CI]: 1.80-8.34, P = 0.001) and history of acute cellular rejection (OR: 3.39, 95% CI: 1.68-6.81, P = 0.001) as predictors of chronic rejection.

CONCLUSION

Although chronic rejection was found to be more common in genetically unrelated donors, the patient survival after LDLT was similar.

Recurrence of disease following organ transplantation in autoimmune liver disease and systemic lupus erythematosus

Disease recurrence after organ transplantation associated with graft failure is a major clinical challenge in autoimmune diseases. Primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC) and autoimmune Hepatitis (AIH) are the three most common (autoimmune liver diseases) ALD for which liver transplantation (LT) is the most effective treatment option for patients with end-stage diseases. Although the 5- and 10-year survival rates of post-LT patients are remarkable (80-84% and 71-79% in PBC, 73-87% and 58-83% in PSC, 76-79% and 67-77% respectively in AIH patients), post-LT disease recurrence is not uncommon. Here, we summarize literature findings on disease recurrence of these ALD with emphasis on the incidence, risk factors and impact on long-term outcome. We noted that the incidence of disease recurrence varies between studies, which ranges from 53% to 10.9% in PBC, 8.2% to 44.7% in PSC and 7% to 42% in AIH. The variations are likely due to differences in study design, such as sample size, duration of studies and follow up time. This is further compounded by the lack of precise clinical diagnosis criteria and biomarkers of disease recurrence in these ALD, variation in post-LT treatment protocols to prevent disease recurrence and a multitude of risk factors associated with these ALD. While recurrence of PBC and AIH does not significantly impact long term outcome including overall survival, recurrent PSC patients often require another LT. Renal transplantation, like LT, is the treatment of choice in patients with end-stage lupus nephritis. While calcineurin inhibitor (CNI) and immunosuppressive drugs have improved the survival rate, post-transplant recurrence of lupus nephritis from surveillance-biopsy proven lupus nephritis range from 30% to 44%. On the other hand, recurrence of post-transplant lupus nephritis from registry survey analysis were only 1.1% to 2.4%. In general, risk factors associated with an increased frequency of post-transplant recurrence of autoimmune diseases are not clearly defined. Large scale multi-center studies are needed to further define guidelines for the diagnosis and clinical management to minimize disease recurrence and improve outcomes of post-transplant patients.

Recurrent and De Novo Autoimmune Hepatitis

Clinical indications for liver transplantation (LT) in patients with autoimmune hepatitis (AIH) are identical to those of patients with other chronic liver diseases that end in acute or semiacute liver failure, decompensated cirrhosis, or hepatocellular carcinoma. Recurrent disease after LT has been reported in 10%-50% of patients with AIH, and the frequency of detection is influenced in part by the use of protocol or clinically indicated liver biopsy. De novo AIH connotes the development of AIH in patients transplanted for liver diseases other than AIH, and it has been reported in 5%-10% of pediatric and 1%-2% of adult recipients. Recurrent disease can negatively impact on graft and patient survival, and retransplantation has been required in 8%-23%. De novo AIH is within the spectrum of graft dysfunction that includes plasma cell-rich rejection, and it can also progress to cirrhosis and graft failure. Treatment for recurrent or de novo disease is based on the conventional regimens for AIH, and corticosteroid therapy alone or combined with azathioprine is standard. Better control of disease activity prior to LT has been associated with less recurrence, and maintenance corticosteroid treatment after LT can reduce its frequency. In conclusion, recurrent AIH is far more frequent than de novo AIH. Both may have negative impacts on graft and patient survival, and early detection and treatment are key objectives. Future investigations must codify the diagnostic criteria for each graft dysfunction, seek diagnostic biomarkers, and evaluate treatments that improve outcomes without increasing the risk of pre- and post-LT infections.

The impact of human leukocyte antigen donor and recipient serotyping and matching on liver transplant graft failure in primary sclerosing cholangitis, autoimmune hepatitis, and primary biliary cholangitis

Human leukocyte antigen (HLA) serotyping is not considered to have significant impact on liver graft survival and does not factor into U.S. organ allocation. Immune-related liver diseases such as primary sclerosing cholangitis (PSC), autoimmune hepatitis (AIH), and primary biliary cholangitis (PBC) have been speculated to represent a disease subgroup that may have significantly different graft outcomes depending on HLA donor/recipient characterization. The aim of this study was to investigate whether HLA serotyping/matching influenced post-transplant graft failure for immune-related liver diseases using the United Network for Organ Sharing database. From 1994 to 2015, 5665 patients underwent first-time liver-only transplants for PSC, AIH, and PBC with complete graft survival and donor/recipient HLA data. Graft failure was noted in 38.6% (2188/5665), and all groups had comparable 5-year graft survival (75.1%-78.8%, P = 0.069). The overall degree of, and loci-specific mismatch level, did not influence outcomes. Multivariable Cox proportional hazards regression noted increased graft failure risk for recipient HLA-B7, HLA-B57, HLA-B75, HLA-DR13 and donor HLA-B55, HLA-B58, and HLA-DR8 for PSC patients, protective effects for recipient HLA-DR1 and HLA-DR3 for AIH patients, and increased risk for HLA-DR7 for AIH patients. These findings warrant further investigation to evaluate the impact of HLA serotyping on post-transplant outcomes.

Post-Transplant Disease Recurrence in Pediatric PSC

PURPOSE OF REVIEW

Review the current knowledge about recurrent primary sclerosing cholangitis (rPSC) after transplant in children.

RECENT FINDINGS

Recurrent PSC is a significant complication that afflicts 16% of children after liver transplantation for primary sclerosing cholangitis (PSC) at a median onset of 38 months post-transplant. Possible risk factors include younger age at PSC diagnosis or transplant, the presence of overlap syndrome or IBD, and post-transplant induction with thymoglobulin. rPSC impairs the patient's quality of life and can be detrimental to the graft. Preventive options and therapeutic measures are limited. Ursodeoxycholic acid is widely used, but its effect on long-term outcome is unknown. Vancomycin can improve the biochemical profile of rPSC, but it remains unknown whether it halts the disease progression. Pediatric liver transplant for primary sclerosis cholangitis can be complicated by recurrence of the disease, which portends poor outcomes. Although few risk factors have been implicated, larger studies with longer follow-ups are needed to characterize cardinal risk factors for rPSC, as well as evaluate possible preventative and therapeutic options.

Human leukocyte antigen, allele, and eplet mismatches in liver transplantation; observations from a small, single center cohort

BACKGROUND

The impact of human leukocyte antigen (HLA) matching on outcomes in liver transplantation is controversial. Varying levels of HLA matching resolutions were examined in a uniform patient population with no pre-transplant DSA from a small, single center cohort.

METHODS

Retrospective chart review from a single center yielded 131 patients, 67 of which were confirmed to be DSA negative, all of which received induction immunotherapy and post-operative immunosuppression. HLA typing was achieved by sequence specific oligonucleotide probe (SSOP) method using LABType® kits. Eplet mismatch analysis was conducted using HLAMatchMaker software.

RESULTS

The mean number of HLA-A antigen mismatches was significantly higher in patients experiencing acute rejection (1.8 vs 1.6, p = 0.006). Rejection patients more frequently possessed two HLA-A mismatches compared to their non-rejection counterparts (77% vs 43%, p = 0.071). Patient survival was found to be non-significantly decreased in patients with a higher eplet mismatch load at the HLA-A locus (p = 0.155). No other loci were found to be predictive.

CONCLUSION

In conclusion, HLA mismatches were found to increase acute rejection and be associated with decreased patient survival. The outcomes of this study suggest an involvement of HLA-A locus mismatches in predicting liver transplant rejection and patient survival.

Delayed Donor Bone Marrow Infusion Induces Liver Transplant Tolerance

BACKGROUND

Nonmyeloablative conditioning followed by donor bone marrow infusion (BMI) to induce tolerance has not been robustly tested in liver transplantation (LT) and may be unsafe at the time of LT. We hypothesized T cell-depleted BMI is effective in inducing tolerance when delayed after LT, resulting in potentially safer future clinical applications.

METHODS

Nonimmunosuppressed syngeneic (Lewis to Lewis) and allogeneic (ACI to Lewis) rat LT transplants were initially performed as controls. Three experimental allogeneic LT groups were treated with tacrolimus (TAC) for 3 to 4 weeks and then underwent: (1) TAC withdrawal alone; (2) nonmyeloablative conditioning (anti-αβTCR mAb + total body irradiation [300 cGy]) followed by TAC withdrawal; (3) Nonmyeloablative conditioning + donor BMI (100 × 10 T cell-depleted bone marrow cells) followed by TAC withdrawal.

RESULTS

All group 1 recipients developed chronic rejection. Group 2 had long-term survival but impaired liver function and high donor-specific antibody (DSA) levels. In contrast, group 3 (conditioning + BMI) had long-term TAC-free survival with preserved liver function and histology, high mixed chimerism and blood/liver/spleen CD4 + CD25 + Foxp3+ regulatory T cells, and low DSA titers, similar to syngeneic grafts. While donor-specific tolerance was observed post-BMI, graft-versus-host disease was not.

CONCLUSIONS

These results support that donor-specific tolerance can be achieved with BMI even when delayed after LT and this tolerance correlates with increased mixed chimerism, regulatory T cell generation, and diminished DSA.

Risk factors for recurrence of primary biliary cholangitis after liver transplantation in female patients: A Japanese multicenter retrospective study

Primary biliary cholangitis (PBC) is diagnosed mainly in female individuals, and risk factors for PBC recurrence (rPBC) after liver transplantation (LT) from cadaveric donors have been reported. We conducted a retrospective multicenter study of rPBC in female patients after living‐donor LT (LDLT). A total of 388 female patients undergoing LDLT for end‐stage PBC were enrolled, and the effects of preoperative and operative factors were evaluated. Postoperative factors were evaluated in 312 patients who survived for more than 1 year post‐LDLT. rPBC was defined as abnormal hepatic enzyme levels with typical histological findings in liver biopsies. Fifty‐eight patients (14.9%) developed rPBC with a median of 4.6 (0.8‐14.5) years post‐LT. Cox hazard analysis (P < 0.05) showed that younger recipient age (hazard ratio, 0.95; 95% confidence interval, 0.920‐0.982), shorter operative time (1.00; 0.995‐0.999), higher serum immunoglobulin M level (1.00; 1.001‐1.002), donor sex mismatch (2.45; 1.268‐4.736), human leukocyte antigen B60 (2.56; 1.336‐4.921) and DR8 (1.98; 1.134‐3.448), and initial treatment with cyclosporine A (3.14; 1.602‐6.138) were significantly associated with rPBC. The frequencies of Child‐Turcotte‐Pugh class C (0.46; 0.274‐0.775), the model of end‐stage liver disease score (0.96; 0.914‐0.998), and updated Mayo risk score (1.02; 1.005‐1.033) were significantly lower in rPBC. Posttransplantation use of steroids decreased and that of antimetabolites increased the frequency of rPBC. Conclusion: The timing of LT, recipient conditions, donor characteristics, and immunosuppressive medications may be associated with rPBC in LT recipients. (Hepatology Communications 2017;1:394–405)

Autoimmune Hepatitis in the Liver Transplant Graft

Recurrent autoimmune hepatitis (AIH) and de novo AIH are 2 important causes of late graft failure after liver transplantation (LT). Recurrent AIH occurs in patients who undergo LT for AIH. De novo AIH occurs in patients who are transplanted for etiologies other than AIH. Although typically treated with standard treatment for AIH, including corticosteroids and azathioprine, both recurrent and de novo AIH may progress to end-stage liver disease requiring retransplantation.

Recurrence of primary sclerosing cholangitis, primary biliary cholangitis and auto-immune hepatitis after liver transplantation

Liver transplantation is a well-accepted treatment for decompensated chronic liver disease due to primary sclerosing cholangitis (PSC), primary biliary cholangitis (PBC) and auto-immune hepatitis (AIH). Survival after liver transplantation is generally good with 1 and 5-year survival rates around 90% and 70-85%. After transplantation, however, these diseases recur in 8.6-27% (rPSC), 10.9-42.3% (rPBC) and 7-42% (rAIH), and this poses significant challenges in terms of management and graft outcome in these patients. In this review we discuss the incidence, clinical presentation, challenges in diagnosis, reported risk factors and impact on post-transplant outcomes of recurrence of PSC, PBC and AIH after liver transplantation. We also discuss some of the limitations of current investigations and formulate idea's for future research objectives.

Systematic review: recurrent autoimmune liver diseases after liver transplantation

BACKGROUND

Autoimmune liver diseases (AILD) constitute the third most common indication for liver transplantation (LT) worldwide. Outcomes post LT are generally good but recurrent disease is frequently observed.

AIMS

To describe the frequency and risk factors associated with recurrent AILD post-LT and provide recommendations to reduce the incidence of recurrence based on levels of evidence.

METHODS

A systematic review was performed for full-text papers published in English-language journals, using the keywords 'autoimmune hepatitis (AIH)', 'primary biliary cholangitis and/or cirrhosis (PBC)', 'primary sclerosing cholangitis (PSC)', 'liver transplantation' and 'recurrent disease'. Management strategies to reduce recurrence after LT were classified according to grade and level of evidence.

RESULTS

Survival rates post-LT are approximately 90% and 70% at 1 and 5 years and recurrent disease occurs in a range of 10-50% of patients with AILD. Recurrent AIH is associated with elevated liver enzymes and IgG before LT, lymphoplasmacytic infiltrates in the explants and lack of steroids after LT (Grade B). Tacrolimus use is associated with increased risk; use of ciclosporin and preventive ursodeoxycholic acid with reduced risk of PBC recurrence (all Grade B). Intact colon, active ulcerative colitis and early cholestasis are associated with recurrent PSC (Grade B).

CONCLUSIONS

Recommendations based on grade A level of evidence are lacking. The need for further study and management includes active immunosuppression before liver transplantation and steroid use after liver transplantation in autoimmune hepatitis; selective immunosuppression with ciclosporin and preventive ursodeoxycholic acid treatment for primary biliary cholangitis; and improved control of inflammatory bowel disease or even colectomy in primary sclerosing cholangitis.

Role of Human Leukocyte Antigen Compatibility in Graft Outcomes After Living Donor Liver Transplantation

PURPOSE

The influence of human leukocyte antigen (HLA) mismatch on liver transplantation has been widely studied, but is still controversial. The aim of this large single-center study was to analyze the role of HLA compatibility between donor and recipient in the graft outcomes of living donor liver transplantation (LDLT).

MATERIALS AND METHODS

A total of 925 recipients who had undergone LDLT between March 2001 and April 2012 were retrospectively analyzed. HLA typing was performed using a standard complement-dependent cytotoxicity technique. The degree and type of HLA-A, HLA-B, and HLA-DR mismatch were assessed. We also investigated the posttransplantation laboratory data, incidence of rejection, recurrence of hepatitis B virus (HBV), and graft survival as outcome parameters.

RESULTS

The type of HLA-A, HLA-B, and HLA-DR mismatch had no effect on rejection episodes, whereas the beneficial effect of a much lower degree (0-2) of HLA mismatch was notable. Recipients with 2 HLA-B mismatches or recipients with a higher degree of mismatch were associated with elevated bilirubin level, a higher recurrence rate of HBV, and inferior graft survival. A complete mismatch of 2 at the DR locus also decreased graft survival in LDLT recipients.

CONCLUSIONS

This study confirmed that the degree of HLA mismatch, as well as the locus-specific type of HLA mismatch, namely B and DR, play a major role in graft outcomes after LDLT. To obtain an improved graft outcome, HLA compatibility should be considered in the setting of LDLT, which provides sufficient time to select a more favorable donor-recipient combination.

Impact of donor-recipient genetic relationship on outcome of living donor liver transplantation

Living donor liver transplantation (LDLT) is a valuable option for expanding the donor pool, especially in localities where deceased organ harvesting is not allowed. In addition, rejection rates were found to be lower in LDLT, which is attributed to the fact that LDLT is usually performed between relatives. However, the impact of genetic relation on the outcome of LDLT has not been studied. In this study, we examined the difference in rejection rates between LDLT from genetically related (GR) donors and genetically unrelated (GUR) donors. All cases that underwent LDLT during the period from May 2004 until May 2014 were included in the study. The study group was divided into 2 groups: LDLT from GR donors and LDLT from GUR donors. A total of 308 patients were included in the study: 212 from GR donors and 96 from GUR donors. Human leukocyte antigen (HLA) typing was not included in the workup for matching donors and recipients. GUR donors were wives (36; 11.7%), sons-in-law (7; 2.3%), brothers-in-law (12; 3.9%), sisters-in-law (1; 0.3%), and unrelated (38; 12.3%). The incidence of acute rejection in the GR group was 17.4% and 26.3% in the GUR group (P value = 0.07). However, there was a significant difference in the incidence of chronic rejection (CR) between the 2 groups: 7% in GR group and 14.7% in the GUR group (P value = 0.03). In terms of overall survival, there was no significant difference between both groups. LDLT from the GUR donors is not associated with a higher incidence of acute cellular rejection. However, CR was significantly lower when grafts were procured from GR donors. HLA matching may be recommended before LDLT from GUR donors. Liver Transplantation 23:43-49 2017 AASLD.

HLA Mismatching Strategies for Solid Organ Transplantation - A Balancing Act

HLA matching provides numerous benefits in organ transplantation including better graft function, fewer rejection episodes, longer graft survival, and the possibility of reduced immunosuppression. Mismatches are attended by more frequent rejection episodes that require increased immunosuppression that, in turn, can increase the risk of infection and malignancy. HLA mismatches also incur the risk of sensitization, which can reduce the opportunity and increase waiting time for a subsequent transplant. However, other factors such as donor age, donor type, and immunosuppression protocol, can affect the benefit derived from matching. Furthermore, finding a well-matched donor may not be possible for all patients and usually prolongs waiting time. Strategies to optimize transplantation for patients without a well-matched donor should take into account the immunologic barrier represented by different mismatches: what are the least immunogenic mismatches considering the patient’s HLA phenotype; should repeated mismatches be avoided; is the patient sensitized to HLA and, if so, what are the strengths of the patient’s antibodies? This information can then be used to define the HLA type of an immunologically optimal donor and the probability of such a donor occurring. A probability that is considered to be too low may require expanding the donor population through paired donation or modifying what is acceptable, which may require employing treatment to overcome immunologic barriers such as increased immunosuppression or desensitization. Thus, transplantation must strike a balance between the risk associated with waiting for the optimal donor and the risk associated with a less than optimal donor.

Association of HLA-A and Non-Classical HLA Class I Alleles

The HLA-A locus is surrounded by HLA class Ib genes: HLA-E, HLA-H, HLA-G and HLA-F. HLA class Ib molecules are involved in immuno-modulation with a central role for HLA-G and HLA-E, an emerging role for HLA-F and a yet unknown function for HLA-H. Thus, the principal objective of this study was to describe the main allelic associations between HLA-A and HLA-H, -G, -F and -E. Therefore, HLA-A, -E, -G, -H and -F coding polymorphisms, as well as HLA-G UnTranslated Region haplotypes (referred to as HLA-G UTRs), were explored in 191 voluntary blood donors. Allelic frequencies, Global Linkage Disequilibrium (GLD), Linkage Disequilibrium (LD) for specific pairs of alleles and two-loci haplotype frequencies were estimated. We showed that HLA-A, HLA-H, HLA-F, HLA-G and HLA-G UTRs were all in highly significant pairwise GLD, in contrast to HLA-E. Moreover, HLA-A displayed restricted associations with HLA-G UTR and HLA-H. We also confirmed several associations that were previously found to have a negative impact on transplantation outcome. In summary, our results suggest complex functional and clinical implications of the HLA-A genetic region.

Autoimmune Liver Disease Post-Liver Transplantation: A Summary and Proposed Areas for Future Research

Autoimmune liver diseases (AILD) are rare diseases with a reported prevalence of less than 50 per 100 000 population. As the research landscape and our understanding of AILDs and liver transplantation evolves, there remain areas of unmet needs. One of these areas of unmet needs is prevention of disease recurrence after liver transplantation. Disease recurrence is not an insignificant event because allograft loss with the need for retransplantation can occur. Patients transplanted for AILD are more likely to experience acute rejection compared to those transplanted for non-AILD, and the reason(s) behind this observation is unclear. Tasks for the future include a better understanding of the pathogenesis of AILD, definition of the precise pathogenetic mechanisms of recurrent AILD, and development of strategies that can identify recipients at risk for disease recurrence. Importantly, the role of crosstalk between alloimmune responses and autoimmune responses in AILD is an important area that needs further study.

This article reviews the relevant literature of de novo autoimmune hepatitis, recurrent autoimmune hepatitis, recurrent primary sclerosing cholangitis, and recurrent primary biliary cirrhosis in terms of the clinical entity, the scientific advancements, and future scientific goals to enhance our understanding of these diseases.

A review of the relevant literature of de novo autoimmune hepatitis, recurrent autoimmune hepatitis, recurrent primary sclerosing cholangitis, and recurrent primary biliary cirrhosis in terms of the clinical entity, the scientific advancements and future scientific goals to enhance our understanding of these diseases.

Recurrence of autoimmune liver diseases after liver transplantation

Liver transplantation (LT) is the most effective treatment modality for end stage liver disease caused by many etiologies including autoimmune processes. That said, the need for transplantation for autoimmune hepatitis (AIH) and primary biliary cirrhosis (PBC), but not for primary sclerosing cholangitis (PSC), has decreased over the years due to the availability of effective medical treatment. Autoimmune liver diseases have superior transplant outcomes than those of other etiologies. While AIH and PBC can recur after LT, recurrence is of limited clinical significance in most, but not all cases. Recurrent PSC, however, often progresses over years to a stage requiring re-transplantation. The exact incidence and the predisposing factors of disease recurrence remain debated. Better understanding of the pathogenesis and the risk factors of recurrent autoimmune liver diseases is required to develop preventive measures. In this review, we discuss the current knowledge of incidence, diagnosis, risk factors, clinical course, and treatment of recurrent autoimmune liver disease (AIH, PBC, PSC) following LT.

Recurrence of autoimmune liver diseases after liver transplantation

Liver transplantation (LT) is the most effective treatment modality for end stage liver disease caused by many etiologies including autoimmune processes. That said, the need for transplantation for autoimmune hepatitis (AIH) and primary biliary cirrhosis (PBC), but not for primary sclerosing cholangitis (PSC), has decreased over the years due to the availability of effective medical treatment. Autoimmune liver diseases have superior transplant outcomes than those of other etiologies. While AIH and PBC can recur after LT, recurrence is of limited clinical significance in most, but not all cases. Recurrent PSC, however, often progresses over years to a stage requiring re-transplantation. The exact incidence and the predisposing factors of disease recurrence remain debated. Better understanding of the pathogenesis and the risk factors of recurrent autoimmune liver diseases is required to develop preventive measures. In this review, we discuss the current knowledge of incidence, diagnosis, risk factors, clinical course, and treatment of recurrent autoimmune liver disease (AIH, PBC, PSC) following LT.

Preventive administration of UDCA after liver transplantation for primary biliary cirrhosis is associated with a lower risk of disease recurrence

BACKGROUND & AIMS

Recurrence of primary biliary cirrhosis (PBC) after liver transplantation (LT) is not rare and can occasionally lead to severe graft dysfunction and retransplantation. Ursodeoxycholic acid (UDCA) is a safe and effective treatment for PBC. However, whether preventive administration of UDCA after LT could lower the incidence of PBC recurrence is unknown.

METHODS

Patients transplanted for PBC in five French and Swiss centers from 1988 to 2010 were included. Most patients from a single center received UDCA (10-15 mg/kg/d) preventively. Recurrence of PBC was histologically defined from biopsies routinely performed at 1, 5, 10, and 15 years of follow-up, and at any time when clinically indicated.

RESULTS

A total of 90 patients with a 1-year minimum follow-up were studied retrospectively, including 19 (21%) patients receiving preventive UDCA. The mean follow-up was 12 years. Recurrence was diagnosed in 48 (53%) patients. The recurrence rates at 5, 10, and 15 years were 27%, 47%, and 61%, respectively. In a multivariate proportional hazards model adjusted for potential confounders and risk factors, preventive UDCA was the only factor affecting the risk of recurrence significantly (HR=0.32; 95% CI: 0.11-0.91). The 5, 10, and 15-year rates of recurrence were 11%, 21%, and 40%, respectively, under preventive UDCA, and 32%, 53%, and 70%, respectively, without preventive UDCA. Seven patients with recurrence (15%) progressed to cirrhosis, requiring retransplantation in one. However, neither recurrence nor preventive UDCA had a significant impact on survival.

CONCLUSIONS

Preventive treatment with UDCA reduces the risk of PBC recurrence after LT.

Liver transplantation and autoimmune hepatitis

Liver Transplantation (LT) is an effective treatment for patients with end-stage liver disease including autoimmune hepatitis (AIH). Indication for LT for AIH does not differ basically from other liver diseases including both acute and chronic types of disease progression, although it is reported to be an infrequent indication for LT worldwide due to the therapeutic advances of immunosuppression. The outcome following LT is feasible, with current patient and graft survival exceeding 75% at 5 years. Recurrent and de-novo AIH posttranslant has also been reported; and this seems to have important clinical implications because its management differs from the standard treatment for allograft rejection. In this review, we discuss the characteristics of AIH, focusing on the indication for LT and issues raised following LT.

Shotgun proteomics: identification of unique protein profiles of apoptotic bodies from biliary epithelial cells

Shotgun proteomics is a powerful analytic method to characterize complex protein mixtures in combination with multidimensional liquid chromatography-tandem mass spectrometry (LC-MS/MS). We used this platform for proteomic characterization of apoptotic bodies in an effort to define the complex protein mixtures found in primary cultures of human intrahepatic biliary epithelial cells (HiBEC), human renal proximal tubular epithelial cells, human bronchial epithelial cells, isolated intrahepatic biliary epithelial cells from explanted primary biliary cirrhosis (PBC), and control liver using a total of 24 individual samples. Further, as additional controls and for purposes of comparison, proteomic signatures were also obtained from intact cells and apoptotic bodies. The data obtained from LC-MS/MS, combined with database searches and protein assembly algorithms, allowed us to address significant differences in protein spectral counts and identify unique pathways that may be a component of the induction of the signature inflammatory cytokine response against BECs, including the Notch signaling pathway, interleukin (IL)8, IL6, CXCR2, and integrin signaling. Indeed, there are 11 proteins that localize specifically to apoptotic bodies of HiBEC and eight proteins that were specifically absent in HiBEC apoptotic bodies.

CONCLUSION

Proteomic analysis of BECs from PBC liver compared to normal liver are significantly different, suggesting that an immunological attack affects the repertoire of proteins expressed and that such cells should be thought of as living in an environment undergoing continuous selection secondary to an innate and adaptive immune response, reflecting an almost "Darwinian" bias.

Survival without biliary complications after liver transplant for primary sclerosing cholangitis

OBJECTIVES

Patients who have a liver transplant for primary sclerosing cholangitis may develop recurrent disease and biliary complications, organ loss necessitating revision liver transplant, or death. We evaluated long-term outcomes in patients who had liver transplant for primary sclerosing cholangitis.

MATERIALS AND METHODS

In 71 patients who had a liver transplant for end-stage liver disease because of primary sclerosing cholangitis, a retrospective review was done to evaluate biliary complication-free survival, transplanted organ survival, and death. Human leukocyte antigen typing and matching were reviewed.

RESULTS

There were 39 patients (55%) who had biliary complications, loss of the liver transplant, or death at a mean 12.1 years after transplant. The 5- and 10-year event-free survival reached 74.6% and 45% (53 patients after 5 years, and 32 patients after 10 years). Male sex of transplant recipients was a significant risk factor for biliary complications, revision liver transplant, or death. Most patients had inflammatory bowel disease, primarily ulcerative colitis. The human leukocyte antigen profile or number of mismatches had no effect on complication-free survival.

CONCLUSIONS

Biliary complications, revision liver transplant, and death are a useful combined primary endpoint for recurrent primary sclerosing cholangitis after liver transplant.

Post-liver transplant hepatitis C virus recurrence: an unresolved thorny problem

Hepatitis C virus (HCV)-related cirrhosis represents the leading cause of liver transplantation in developed, Western and Eastern countries. Unfortunately, liver transplantation does not cure recipient HCV infection: reinfection universally occurs and disease progression is faster after liver transplant. In this review we focus on what happens throughout the peri-transplant phase and in the first 6-12 mo after transplantation: during this crucial period a completely new balance between HCV, liver graft, the recipient's immune response and anti-rejection therapy is achieved that will deeply affect subsequent outcomes. Nearly all patients show an early graft reinfection, with HCV viremia reaching and exceeding pre-transplant levels; in this setting, histological assessment is essential to differentiate recurrent hepatitis C from acute or chronic rejection; however, differentiating the two patterns remains difficult. The host immune response (mainly cellular mediated) appears to be crucial both in the control of HCV infection and in the genesis of rejection, and it is also strongly influenced by immunosuppressive treatment. At present no clear immunosuppressive strategy could be strongly recommended in HCV-positive recipients to prevent HCV recurrence, even immunotherapy appears to be ineffective. Nonetheless it seems reasonable that episodes of rejection and over-immunosuppression are more likely to enhance the risk of HCV recurrence through immunological mechanisms. Both complete prevention of rejection and optimization of immunosuppression should represent the main goals towards reducing the rate of graft HCV reinfection. In conclusion, post-transplant HCV recurrence remains an unresolved, thorny problem because many factors remain obscure and need to be better determined.

Autoimmune liver disease, autoimmunity and liver transplantation

Primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC) and autoimmune hepatitis (AIH) represent the three major autoimmune liver diseases (AILD). PBC, PSC, and AIH are all complex disorders in that they result from the effects of multiple genes in combination with as yet unidentified environmental factors. Recent genome-wide association studies have identified numerous risk loci for PBC and PSC that host genes involved in innate or acquired immune responses. These loci may provide a clue as to the immune-based pathogenesis of AILD. Moreover, many significant risk loci for PBC and PSC are also risk loci for other autoimmune disorders, such type I diabetes, multiple sclerosis and rheumatoid arthritis, suggesting a shared genetic basis and possibly similar molecular pathways for diverse autoimmune conditions. There is no curative treatment for all three disorders, and a significant number of patients eventually progress to end-stage liver disease requiring liver transplantation (LT). LT in this context has a favourable overall outcome with current patient and graft survival exceeding 80% at 5years. Indications are as for other chronic liver disease although recent data suggest that while lethargy improves after transplantation, the effect is modest and variable so lethargy alone is not an indication. In contrast, pruritus rapidly responds. Cholangiocarcinoma, except under rigorous selection criteria, excludes LT because of the high risk of recurrence. All three conditions may recur after transplantation and are associated with a greater risk of both acute cellular and chronic ductopenic rejection. It is possible that a crosstalk between alloimmune and autoimmune response perpetuate each other. An immunological response toward self- or allo-antigens is well recognised after LT in patients transplanted for non-autoimmune indications and sometimes termed "de novo autoimmune hepatitis". Whether this is part of the spectrum of rejection or an autoimmune process is not clear. In this manuscript, we review novel findings about disease processes and mechanisms that lead to autoimmunity in the liver and their possible involvement in the immune response vs. the graft after LT.