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The Banff Working Group on Liver Allograft Pathology met in September 2022. Participants included hepatologists, surgeons, pathologists, immunologists, and histocompatibility specialists. Presentations and discussions focused on the evaluation of long-term allograft health, including noninvasive and tissue monitoring, immunosuppression optimization, and long-term structural changes. Potential revision of the rejection classification scheme to better accommodate and communicate late T cell-mediated rejection patterns and related structural changes, such as nodular regenerative hyperplasia, were discussed. Improved stratification of long-term maintenance immunosuppression to match the heterogeneity of patient settings will be central to improving long-term patient survival. Such personalized therapeutics are in turn contingent on a better understanding and monitoring of allograft status within a rational decision-making approach, likely to be facilitated in implementation with emerging decision-support tools. Proposed revisions to rejection classification emerging from the meeting include the incorporation of interface hepatitis and fibrosis staging. These will be opened to online testing, modified accordingly, and subject to consensus discussion leading up to the next Banff conference., Competing Interests: Declaration of competing interest The authors of this manuscript have conflicts of interest to disclose as described by the American Journal of Transplantation. Annette Jackson: HLA consultant (Hansa Biopharma); Research reagents/grant (CareDx); Speaker bureau (One Lambda/ThermoFisher). Josh Levitsky: Advisor (Eurofins; eGenesis); Speaker for Takeda; Mallinckrodt. Richard Taubert: Research grant (Oncocyte/Chronix Biomedical). The other authors have no conflict of interest to disclose., (Crown Copyright © 2024. Published by Elsevier Inc. All rights reserved.)

The Banff Working Group on Liver Allograft Pathology reviewed and discussed literature evidence regarding antibody-mediated liver allograft rejection at the 11th (Paris, France, June 5-10, 2011), 12th (Comandatuba, Brazil, August 19-23, 2013), and 13th (Vancouver, British Columbia, Canada, October 5-10, 2015) meetings of the Banff Conference on Allograft Pathology. Discussion continued online. The primary goal was to introduce guidelines and consensus criteria for the diagnosis of liver allograft antibody-mediated rejection and provide a comprehensive update of all Banff Schema recommendations. Included are new recommendations for complement component 4d tissue staining and interpretation, staging liver allograft fibrosis, and findings related to immunosuppression minimization. In an effort to create a single reference document, previous unchanged criteria are also included., (© Copyright 2016 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Mutations in MCM9, which encodes DNA helicase, were recently shown to cause a clinical phenotype of primary ovarian failure and chromosomal instability. MCM9 plays an essential role in homologous recombination-mediated double-strand break repair. We describe a multiplex family with early colorectal carcinoma and mixed polyposis associated with primary hypergonadotropic hypogonadism. A combination of whole genome homozygosity mapping as well as exome sequencing and targeted gene sequencing identified a homozygous c.672_673delGGinsC mutation that predicts a truncated protein, p.Glu225Lysfs*4. Our data expand the phenotypic spectrum of MCM9 mutations and suggest a link between MCM9 and inherited predisposition to mixed polyposis and early-onset colorectal cancer., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Extended partial hepatectomy may be needed in cases of large hepatic mass, and can lead to fulminant hepatic failure. Macroporous alginate scaffold is a biocompatible matrix which promotes the growth, differentiation and long-term hepatocellular function of primary hepatocytes in vitro. Our aim was to explore the ability of implanted macroporous alginate scaffolds to protect liver remnants from acute hepatic failure after extended partial hepatectomy. An 87% partial hepatectomy (PH) was performed on C57BL/6 mice to compare non-treated mice to mice in which alginate or collagen scaffolds were implanted after PH. Mice were scarified 3, 6, 24 and 48 h and 6 days following scaffold implantation and the extent of liver injury and repair was examined. Alginate scaffolds significantly increased animal survival to 60% vs. 10% in non-treated and collagen-treated mice (log rank=0.001). Mice with implanted alginate scaffolds manifested normal and prolonged aspartate aminotransferases and alanine aminotransferases serum levels as compared with the 2- to 20-fold increase in control groups (P<0.0001) accompanied with improved liver histology. Sustained normal serum albumin levels were observed in alginate-scaffold-treated mice 48 h after hepatectomy. Incorporation of BrdU-positive cells was 30% higher in the alginate-scaffold-treated group, compared with non-treated mice. Serum IL-6 levels were significantly decreased 3h post PH. Biotin-alginate scaffolds were quickly well integrated within the liver tissue. Collectively, implanted alginate scaffolds support liver remnants after extended partial hepatectomy, thus eliminating liver injury and leading to enhanced animal survival after extended partial hepatectomy., (Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Background & Aims: Interleukin-6 (IL-6) is a crucial factor in liver regeneration following partial hepatectomy (PH); however, the role of IL-6 and IL-6 trans-signaling in particular, in hepatocyte mitosis remains controversial. IL-6 trans-signaling relies upon the release of the soluble IL-6R (sIL-6R), which binds IL-6 to form an agonistic IL-6/sIL-6R complex. Herein we have examined the hypothesis that IL-6 trans-signaling plays a crucial and distinct role in liver regeneration following PH., Methods: The specific IL-6/sIL-6R antagonist, sgp130Fc, was expressed in mice and analyzed for its effect on hepatocyte mitosis following PH. Alternatively, we examined the effect of the IL-6/sIL-6R super-agonist, Hyper-IL-6, or IL-6 expressed either alone or in combination with hepatocyte growth factor (HGF) on hepatocyte mitosis in the absence of PH., Results: Following PH, the dramatic rise of circulating IL-6 levels is accompanied by a concurrent ∼2-fold increase in circulating sIL-6R levels. Ectopic expression of sgp130Fc reduced hepatocyte mitosis by about 40% at early times following PH, while substantially reducing AKT, but not STAT3, activation. But, ectopic Hyper-IL-6 expression in mice without PH was not mitogenic to hepatocytes in vivo. Rather, Hyper-IL-6, but not IL-6, markedly increased HGF-induced hepatocyte mitosis. This cooperative effect correlated with greater resistance of HIL-6 than IL-6 to HGF-mediated reduction of AKT activation, rather than changes in STAT3 or MAPK signaling, and was completely blocked by PI3K inhibition., Conclusions: Following PH, IL-6/sIL-6R cooperates with growth factors, through a PI3K/AKT-dependent mechanism to promote entry of hepatocytes into the cell cycle., (Copyright © 2010 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.)

Recently, we have demonstrated the feasibility of using hemodynamic response imaging (HRI), a functional magnetic resonance imaging (MRI) method combined with hypercapnia and hyperoxia, for monitoring vascular changes during liver pathologies without the need of contrast material. In this study, we evaluated HRI ability to assess changes in liver tumor vasculature during tumor establishment, progression, and antiangiogenic therapy. Colorectal adenocarcinoma cells were injected intrasplenically to model colorectal liver metastasis (CRLM) and the Mdr2 knockout mice were used to model primary hepatic tumors. Hepatic perfusion parameters were evaluated using the HRI protocol and were compared with contrast-enhanced (CE) MRI. The hypovascularity and the increased arterial blood supply in well-defined CRLM were demonstrated by HRI. In CRLM-bearing mice, the entire liver perfusion was attenuated as the HRI maps were significantly reduced by 35%. This study demonstrates that the HRI method showed enhanced sensitivity for small CRLM (1-2 mm) detection compared with CE-MRI (82% versus 38%, respectively). In addition, HRI could demonstrate the vasculature alteration during CRLM progression (arborized vessels), which was further confirmed by histology. Moreover, HRI revealed the vascular changes induced by rapamycin treatment. Finally, HRI facilitates primary hepatic tumor characterization with good correlation to the pathologic differentiation. The HRI method is highly sensitive to subtle hemodynamic changes induced by CRLM and, hence, can function as an imaging tool for understanding the hemodynamic changes occurring during CRLM establishment, progression, and antiangiogenic treatment. In addition, this method facilitated the differentiation between different types of hepatic lesions based on their vascular profile noninvasively.

Beta-glucosylceramide has been shown to affect natural killer T cell function in models of inflammation. We, therefore, investigated the effects of different beta-glycosphingolipids, including beta-glucosylceramide, on STAT (signal transducers and activators of transcription) signaling pathways and determined whether these effects were mediated by lipid raft microdomains and/or CD1d molecules. The effects of alpha- and beta-structured ligands on the lipid raft protein flotillin-2 were studied in both natural killer T hybridoma cells and leptin-deficient mice. To determine whether CD1d was involved in the effects of the beta-glycosphingolipids, an anti-CD1d blocking antibody was used in a cell proliferation assay system. The downstream effects on the protein phosphorylation levels of STAT1, STAT3, and STAT6 were examined in both immune-mediated hepatitis and hepatoma models. The effects of beta-glycosphingolipids on the STAT signaling pathways were found to be dependent on CD1d. Lipid rafts were affected by both the dose and ratio of the beta-glycosphingolipids and the acyl chain length, and these effects were followed by downstream effects on STAT proteins. Our results show that beta-glycosphingolipids have beneficial effects in natural killer T cell-dependent immune-mediated metabolic and malignant animal models in vivo.

The aim of this study was to determine the effect of beta-glycosphingolipids on intra-hepatic natural killer T (NKT) lymphocyte regulatory function and on lymphocyte trapping via alteration of cell membrane lipid rafts. Immune-mediated colitis was induced by intracolonic instillation of trinitrobenzene sulfonic acid. Mice were treated with beta-lactosylceramide (LC), beta-glucosylceramide (GC), beta-galactosylceramide, ceramide, or a combination of both GC and LC (IGL), or solvent alone. Lipid rafts were investigated by fluorescence-activated cell sorting analysis of ganglioside-GM1 and fluorescence microscopy of structure. Administration of beta-glycosphingolipids resulted in an increased intrahepatic/peripheral NKT ratio, increased intrahepatic CD8+ lymphocyte trapping, decreased serum interferon-gamma (IFN-gamma) levels and decreased serum IFN-gamma/interleukin-10 ratio. Administration of GC, LC, or IGL significantly altered the levels of GM1, a key marker of lipid rafts, on NKT regulatory lymphocytes. The immune modulatory effect of beta-glycosphingolipids was associated with increased survival and significant alleviation of colitis as determined by improvement in both the macroscopic and microscopic scores. In conclusion, administration of beta-glycosphingolipids increased NKT regulatory lymphocyte redistribution and intrahepatic CD8(+) T lymphocyte trapping, resulting in alleviation of immune-mediated colitis. The effects of these naturally occurring compounds were associated with modification of the T lymphocyte lipid raft structure, which is a site for immune modulation.

Background/aims: Nutritional supplements are frequently considered to be harmless but indiscriminate use of unlabelled ingredients may lead to significant adverse reactions., Methods: In 2004, identification of four index cases of acute hepatitis associated with Herbalife intake led to a ministry of health investigation in all Israeli hospitals. Twelve patients with acute idiopathic liver injury in association with consumption of Herbalife products were investigated., Results: Eleven of the patients were females, aged 49.5+/-13.4 y. One patient had stage I primary biliary cirrhosis and another had hepatitis B. Acute liver injury was diagnosed after 11.9+/-11.1 months of initiation of Herbalife consumption. Liver biopsies demonstrated active hepatitis, portal inflammation rich with eosinophils, ductular reaction and parenchymal inflammation with peri-central accentuation. One patient developed sub-fulminant and two fulminant episodes of hepatic failure. Hepatitis resolved in eleven patients, while one patient succumbed to complications following liver transplantation. Three patients resumed consumption of Herbalife products following normalization of liver enzymes, resulting in a second bout of hepatitis., Conclusions: An association between intake of Herbalife products and acute hepatitis was identified in Israel. We call for prospective evaluation of Herbalife products for possible hepatotoxicity. Until then, caution should be exercised by consumers, especially among individuals suffering from underlying liver disease.

Background/aims: Leptin exerts potent immune modulatory properties. The aim of this study was to determine leptin's anti-tumor effect in a murine model of hepatocellular carcinoma (HCC)., Methods: In vivo, athymic nude mice were transplanted with Hep3B cells, followed by daily leptin administration for 6 weeks., Results: Leptin administration induced a significant reduction in tumor size, improved survival rate, and was associated with a significant increase in peripheral natural killer (NK) cell number. Splenocytes from leptin-treated mice featured decreased expression of CIS mRNA. SCID mice featured a similar leptin-associated tumor suppression. In contrast, NK-deficient SCID-beige mice developed larger tumors which were unresponsive to leptin. NK cells incubated in vitro with increasing doses of leptin demonstrated increased cytotoxicity and proliferation. Incubation of leptin with hepatoma cells induced a dose-dependent reduction in proliferation, suggesting a direct anti-tumor effect. Leptin induced increased mRNA expression of STAT2 and SOCS1 on HCC cell lines., Conclusions: Leptin administration induces a significant suppression of human HCC. This effect is mediated by induction of natural killer cell proliferation and activation, along with direct inhibition of tumor growth. Decreased NK expression of inhibitory CIS and over-expression of the antiproliferative STAT2 and SOCS1 proteins in HCC lines may underline the anti-cancerous effects of leptin.

CTLA-4.Fas ligand (CTLA-4.FasL), a paradigmatic 'trans signal converter protein (TSCP)', can attach to APC (via CTLA-4 binding to B7) and direct intercellular inhibitory signals to responding T cells (via FasL binding to Fas receptor), converting an activating APC-to-T cell signal into an inhibitory one. Our previous studies established that CTLA-4.FasL inhibits human primary mixed lymphocyte reactions (MLR) and induces alloantigen-specific hyporesponsiveness ex vivo. The present study extends this to an in vivo context. Using splenocytes from MHC-mismatched C57BL/6 and Balb/c mice, we demonstrated that his(6)CTLA-4.FasL, effectively inhibits murine MLR. Moving in vivo, we demonstrated that subcutaneously administered his(6)CTLA-4.FasL modulates the in vivo response of infused allogeneic splenocytes. his(6)CTLA-4.FasL reduces the number of cells in each cell division, and increases the percentage of dead cells in each division. These findings are consistent with an antigen-induced cell death of the alloreactive cells, and bolsters recombinant TCSP promise as a therapeutic for transplantation diseases.

Background: Primary hepatic sarcoma is a rare tumour with a poor prognosis., Methods: From 1997 to 2002 eight patients had liver resection for primary sarcoma of the liver at our institution. The clinical characteristics, imaging findings, surgical procedures, adjuvant therapy and outcome were retrospectively reviewed. There were two patients each with angiosarcoma (AS), leiomyosarcoma (LMS), and undifferentiated embryonal sarcoma (UES), one patient with epithelioid hemangioendothelioma (EHE) and one patient with malignant peripheral nerve sheath sarcoma (PNSS)., Results: The most common presenting symptoms were right upper quadrant pain and fever. Typical imaging findings were a heterogenous mass with poorly defined margins, pseudocapsule and aberrant vasculature. Preoperative diagnosis of a primary liver sarcoma was made in 7/8 cases, either by fine needle aspiration (n = 5) or angiography (n = 2). Five right hepatectomies and three trisegmentectomies were performed. An R (0) resection was possible in three cases. Two patients developed complications and there was one death. Adjuvant chemoradiotherapy was administered to 5/7 patients. Systemic chemotherapy led to tumour regression in both patients with UES which enabled a second hepatic resection., Conclusions: The majority of patients with primary liver sarcoma present with right upper quadrant pain, fever and a liver mass. Differentiating the rare primary liver sarcoma from the much more common hepatocellular carcinoma (HCC) may aid in planning therapy. Patients with resectable tumours should be referred for surgery. Liver resection combined with adjuvant chemotherapy are the mainstays of treatment for UES in the adult.

Mast cells have been implicated in the ethiopathology of post-operative peritoneal adhesions. However an evaluation of their role in this condition is missing. Adhesions were induced in rats using small intestinal scraping. These rats or rats injected ip with either Stem Cell Factor (SCF) or nedocromil sodium or compound 48/80 (day 0-20) were sacrificed for grading of peritoneal adhesions, for evaluating mast cells and inflammatory cells in adhesions and peritoneal lavage (histochemical staining) and for histamine content (peritoneal lavage, radioenzymatic assay) on days 1-21. Mast cell sonicate was added to intestinal fibroblast and their proliferation was assessed (cell counting). All the rats developed adhesions (day 1) and after 3 days the adhesion score remained constant. Early adhesions were avascular and made of fibrinous exudate containing many mast cells. Thereafter adhesions became denser, and the number of stainable mast cells decreased and then stabilized. On the first few days, inflammatory cells in the peritoneal lavage increased while mast cells and histamine content were significantly reduced indicating their activation. Injection of SCF for 1 week slightly increased peritoneal adhesion formation while nedocromil sodium reduced their development. Compound 48/80 had no significant influence. Addition of mast cell sonicate to normal intestine or to peritoneal adhesion fibroblasts resulted in a significant increase of fibroblast proliferation. In conclusion, mast cell presence correlated with the establishment of peritoneal adhesions, and their pharmacological modulation influenced adhesion formation. In vitro mast cell induced fibroplasia. Therefore, mast cells have a profibrogenic role in this model of peritoneal adhesions.

The human heparanase gene, an endo-beta-glucuronidase that cleaves heparan sulfate at specific intrachain sites, has recently been cloned and shown to function in tumor progression and metastatic spread. Antisense digoxigenin-labeled heparanase RNA probe and monoclonal anti-human heparanase antibodies were used to examine the expression of the heparanase gene and protein in normal, dysplastic, and neoplastic human colonic mucosa. To our knowledge, this is the first systematic study of heparanase expression in human colon cancer. Both the heparanase gene and protein were expressed at early stages of neoplasia, already at the stage of adenoma, but were practically not detected in the adjacent normal-looking colon epithelium. Gradually increasing expression of heparanase was evident as the cells progressed from severe dysplasia through well-differentiated to poorly differentiated colon carcinoma. Deeply invading colon carcinoma cells showed the highest levels of the heparanase mRNA and protein associated with expression of both the gene and enzyme by adjacent desmoplastic stromal fibroblasts. A high expression was also found in colon carcinoma metastases to lung, liver, and lymph nodes, as well as in the accompanying stromal fibroblasts. Moreover, extracts derived from tumor tissue expressed much higher levels of the heparanase protein and activity as compared to the normal colon tissue. In all specimens, the heparanase gene and protein exhibited the same pattern of expression. These results suggest a role of heparanase in colon cancer progression and may have both prognostic and therapeutic applications.

Background: Tacrolimus (FK506) is an effective immunosuppressant for human heart transplantation, but information about its effects on cardiac allograft and nonallograft kidney and liver histopathologic study is limited., Methods: We therefore reviewed 1145 endomyocardial biopsy specimens and eight autopsy results from 80 heart transplant recipients who received tacrolimus as baseline immunosuppression. These were compared with 619 endomyocardial biopsy specimens and four autopsy results from 51 patients treated with cyclosporine-based immunosuppression with lympholytic induction (CLI) by use of rabbit anti-thymocyte globulin. Twenty-one histologic features including the International Society for Heart and Lung Transplantation histopathologic grade were retrospectively assessed without knowledge of the treatment regimen. The lymphocyte growth index on biopsy specimens obtained from these patients was also compared., Results: In general, there were no qualitative differences in the histopathologic appearance of various allograft syndromes between tacrolimus- and CLI-treated patients. Thus histopathologic criteria used to diagnose various graft syndromes are applicable under tacrolimus immunosuppression. However, early (between 10 and 30 days) after transplantation, biopsy specimens from patients treated with tacrolimus showed a significantly higher percentage of inflamed fragments (p = 0.02), the inflammation tended to be more severe (p = 0.09), and the rejection grade tended to be slightly higher (p = 0.08). In contrast, during the late transplantation period (275 to 548 days), biopsy specimens from patients treated with CLI showed a significantly higher percentage of inflamed fragments (p = 0.03), more severe inflammation (p = 0.03), higher rejection grades (p = 0.01), and a higher frequency of Quilty lesions (p = 0.05). Although overall freedom from any grade 3A or higher rejection was greater in the CLI-treated arm, tacrolimus was successfully used to treat refractory rejection in three patients from the CLI-treated arm. Concern has been raised in the literature about the possibility of tacrolimus being a direct hepatotoxin and an accelerant of allograft obliterative arteriopathy. However, no evidence to support either of these contentions was detected in this patient population. In contrast, tacrolimus is clearly nephrotoxic, although similar to cyclosporine in this regard., Conclusions: Tacrolimus is an effective immunosuppressive drug for heart transplantation. The cardiac allograft histopathologic study of patients treated with tacrolimus immunosuppression does not significantly differ from those given conventional, cyclosporine-based triple therapy with lympholytic induction.