Single-cell, single-nucleus, and spatial transcriptomics characterization of the immunological landscape in the healthy and PSC human liver.

BACKGROUND & AIMS: Primary sclerosing cholangitis (PSC) is an immune-mediated cholestatic liver disease for which there is an unmet need to understand the cellular composition of the affected liver and how it underlies disease pathogenesis. We aimed to generate a comprehensive atlas of the PSC liver using multi-omic modalities and protein-based functional validation. METHODS: We employed single-cell and single-nucleus RNA sequencing (47,156 cells and 23,000 nuclei) and spatial transcriptomics (one sample by 10x Visium and five samples with Nanostring GeoMx DSP) to profile the cellular ecosystem in 10 PSC livers. Transcriptomic profiles were compared to 24 neurologically deceased donor livers (107,542 cells) and spatial transcriptomics controls, as well as 18,240 cells and 20,202 nuclei from three PBC livers. Flow cytometry was performed to validate PSC-specific differences in immune cell phenotype and function. RESULTS: PSC explants with parenchymal cirrhosis and prominent periductal fibrosis contained a population of cholangiocyte-like hepatocytes that were surrounded by diverse immune cell populations. PSC-associated biliary, mesenchymal, and endothelial populations expressed chemokine and cytokine transcripts involved in immune cell recruitment. Additionally, expanded CD4+ T cells and recruited myeloid populations in the PSC liver expressed the corresponding receptors to these chemokines and cytokines, suggesting potential recruitment. Tissue-resident macrophages, by contrast, were reduced in number and exhibited a dysfunctional and downregulated inflammatory response to lipopolysaccharide and interferon-γ stimulation. CONCLUSIONS: We present a comprehensive atlas of the PSC liver and demonstrate an exhaustion-like phenotype of myeloid cells and markers of chronic cytokine expression in late-stage PSC lesions. This atlas expands our understanding of the cellular complexity of PSC and has potential to guide the development of novel treatments. IMPACT AND IMPLICATIONS: Primary sclerosing cholangitis (PSC) is a rare liver disease characterized by chronic inflammation and irreparable damage to the bile ducts, which eventually results in liver failure. Due to a limited understanding of the underlying pathogenesis of disease, treatment options are limited. To address this, we sequenced healthy and diseased livers to compare the activity, interactions, and localization of immune and non-immune cells. This revealed that hepatocytes lining PSC scar regions co-express cholangiocyte markers, whereas immune cells infiltrate the scar lesions. Of these cells, macrophages, which typically contribute to tissue repair, were enriched in immunoregulatory genes and demonstrated a lack of responsiveness to stimulation. These cells may be involved in maintaining hepatic inflammation and could be a target for novel therapies.

Pursuing living donor liver transplantation improves outcomes of patients with autoimmune liver diseases: An intention-to-treat analysis.

Living donor liver transplantation (LDLT) offers the opportunity to decrease waitlist time and mortality for patients with autoimmune liver disease (AILD), autoimmune hepatitis, primary biliary cholangitis, and primary sclerosing cholangitis. We compared the survival of patients with a potential living donor (pLDLT) on the waitlist versus no potential living donor (pDDLT) on an intention-to-treat basis. Our retrospective cohort study investigated adults with AILD listed for a liver transplant in our program between 2000 and 2021. The pLDLT group comprised recipients with a potential living donor. Otherwise, they were included in the pDDLT group. Intention-to-treat survival was assessed from the time of listing. Of the 533 patients included, 244 (43.8%) had a potential living donor. Waitlist dropout was higher for the pDDLT groups among all AILDs (pDDLT 85 [29.4%] vs. pLDLT 9 [3.7%], p < 0.001). The 1-, 3-, and 5-year intention-to-treat survival rates were higher for pLDLT versus pDDLT among all AILDs (95.7% vs. 78.1%, 89.0% vs. 70.1%, and 87.1% vs. 65.5%, p < 0.001). After adjusting for covariates, pLDLT was associated with a 38% reduction in the risk of death among the AILD cohort (HR: 0.62, 95% CI: 0.42-0.93 [ p <0.05]), and 60% among the primary sclerosing cholangitis cohort (HR: 0.40, 95% CI: 0.22-0.74 [ p <0.05]). There were no differences in the 1-, 3-, and 5-year post-transplant survival between LDLT and DDLT (AILD: 95.6% vs. 92.1%, 89.9% vs. 89.4%, and 89.1% vs. 87.1%, p =0.41). This was consistent after adjusting for covariates (HR: 0.97, 95% CI: 0.56-1.68 [ p >0.9]). Our study suggests that having a potential living donor could decrease the risk of death in patients with primary sclerosing cholangitis on the waitlist. Importantly, the post-transplant outcomes in this population are similar between the LDLT and DDLT groups.

Analysis of various ATP-binding cassette transporters revealed quantification of ABCB4 as a potential diagnostic tool in primary sclerosing cholangitis (PSC).

AIMS: ATP-binding cassette transporters are important proteins in regulating bile constituent transport between hepatocytes and the bile canalicular system. Dysfunctional transporters lead to accumulation of toxic bile components within hepatocytes or the biliary system, known as cholestasis, resulting in liver damage. It has been previously reported that two particular ATP-binding cassette transporters, ABCB4 and ABCB11, have altered expression in patients with primary sclerosing cholangitis (PSC). Interested in further analysis of expression patterns of ATP-binding cassette transporters in PSC patients, we investigated liver samples from 201 patients, including 43 patients with PSC and 51 patients with primary biliary cholangitis patients (PBC). In addition to ABCB4 and ABCB11, we also included other ATP-binding cassette transporters, to determine if upregulation of ABCB4 and ABCB11 is specifically found in the liver of patients with PSC. METHODS AND RESULTS: Retrospectively, formalin-fixed and paraffin-embedded liver biopsies, resections, and explants were selected to investigate the expression of ABCB1, ABCB4, ABCB11, ABCG5/8, and FXR1 using nanoString nCounter and immunohistochemistry for validation of differently expressed transporters seen in PSC liver samples in comparison to non-PSC liver specimens. Strikingly, ABCB4 was the only ATP-binding cassette transporter showing increased gene and protein expression in hepatocytes of PSC livers when compared to non-PSC liver specimens. Furthermore, ABCB4 protein expression also correlated with disease stage in PSC. CONCLUSION: Our study concluded that altered ABCB4 expression is specifically seen in liver specimens of PSC patients. Therefore, quantitative ABCB4 analysis may be an additional useful tool for the histopathological diagnosis of PSC to distinguish this entity from other cholangiopathies.

Unraveling the Complexity of Liver Disease One Cell at a Time.

The human liver is a complex organ made up of multiple specialized cell types that carry out key physiological functions. An incomplete understanding of liver biology limits our ability to develop therapeutics to prevent chronic liver diseases, liver cancers, and death as a result of organ failure. Recently, single-cell modalities have expanded our understanding of the cellular phenotypic heterogeneity and intercellular cross-talk in liver health and disease. This review summarizes these findings and looks forward to highlighting new avenues for the application of single-cell genomics to unravel unknown pathogenic pathways and disease mechanisms for the development of new therapeutics targeting liver pathology. As these technologies mature, their integration into clinical data analysis will aid in patient stratification and in developing treatment plans for patients suffering from liver disease.

Superior Long-Term Outcomes of Adult Living Donor Liver Transplantation: A Cumulative Single-Center Cohort Study With 20 Years of Follow-Up.

Living donor liver transplantation (LDLT) is an attractive alternative to deceased donor liver transplantation (DDLT). Although both modalities have similar short-term outcomes, long-term outcomes are not well studied. We compared the 20-year outcomes of 668 adults who received LDLT with1596 DDLTs at the largest liver transplantation (LT) program in Canada. Recipients of LDLT were significantly younger and more often male than DDLT recipients (P < 0.001). Autoimmune diseases were more frequent in LDLT, whereas viral hepatitis and alcohol-related liver disease were more frequent in DDLT. LDLT recipients had lower Model for End-Stage Liver Disease scores (P = 0.008), spent less time on the waiting list (P < 0.001), and were less often inpatients at the time of LT (P < 0.001). In a nonadjusted analysis, 1-year, 10-year, and 20-year patient survival rates were significantly higher in LDLT (93%, 74%, and 56%, respectively) versus DDLT (91%, 67%, and 46%, respectively; log-rank P = 0.02) as were graft survival rates LDLT (91%, 67%, and 50%, respectively) versus (90%, 65%, and 44.3%, respectively, for DDLT; log-rank P = 0.31). After multivariable adjustment, LDLT and DDLT were associated with a similar hazard of patient and graft survival. Our data of 20 years of follow-up of LDLT from a single, large Western center demonstrates excellent long-term outcomes for recipients of LDLT.

Renal Dysfunction After Liver Transplantation: Effect of Donor Type.

Recipients of donation after circulatory death (DCD) grafts are reportedly at higher risk of developing renal dysfunction after liver transplantation (LT). We compared the development of acute kidney injury (AKI) and chronic kidney disease (CKD) after LT in recipients of DCD versus donation after brain death (DBD) or living donor liver transplantation (LDLT) livers. Adult recipients of DBD, LDLT, and DCD between 2012 and 2016 at Toronto General Hospital were included. AKI was defined as a post-LT increase of serum creatinine (sCr) ≥26.5 µmol/L within 48 hours or a ≥50% increase from baseline, and CKD was defined as an estimated glomerular filtration rate <60 mL/minute for >3 months. A total of 681 patients (DCD, n = 57; DBD, n = 446; and LDLT, n = 178) with similar baseline comorbidities were included. Perioperative AKI (within the first 7 postoperative days) was observed more frequently in the DCD group (61%; DBD, 40%; and LDLT, 44%; P = 0.01) and was associated with significantly higher peak AST levels (P < 0.001). Additionally, patients in the DCD group had a significantly higher peak sCr (P < 0.001) and a trend toward higher rates of AKI stage 3 (DCD, 33%; DBD, 21%; LDLT, 21%; P = 0.11). The proportions of recovery from AKI (DCD, 77%; DBD, 72%; LDLT, 78%; P = 0.45) and patients developing CKD (DCD, 33%; DBD, 32%; LDLT, 32%; P = 0.99) were similar. Nevertheless, patients who received DCD or DBD LT and required perioperative renal replacement therapy showed significantly lower patient survival in multivariate analysis (hazard ratio, 7.90; 95% confidence interval, 4.51-13.83; P < 0.001). In conclusion, recipients of DCD liver grafts experience higher rates of short-term post-LT renal dysfunction compared with DBD or LDLT. Additional risk factors for the development of severe kidney injury, such as high Model for End-Stage Liver Disease score, massive transfusions, or donor age ≥60 years should be avoided.

Effect of vessel preservation on splenic volume and function in patients with spleen preserving distal pancreatectomies.

BACKGROUND: Spleen preservation during distal pancreatectomy (SpDP) can be accomplished by a variety of surgical approaches, but the impact on spleen function is unknown. This study aimed to compare spleen volume, function and complications between patients who underwent vessel sparing (VSDP) vs. vessel ligating (Warshaw, WDP) SpDP. METHODS: All patients who underwent SpDP at the Toronto General Hospital from 2006 to 2015 were included. Primary outcomes were pre- and post-operative spleen volumes and contrast enhancement on CT, hematologic parameters, and spleen-related complications. RESULTS: 82 patients underwent SpDP with median follow up of 20.4 months. Splenic volumes were able to be calculated on 44 patients (VSDP n = 8, WDP n = 36). There was no difference between WDP and VSDP in operative duration, blood loss, hospital length of stay, or Clavien-Dindo ≥3 complication rate. Spleen volumes did not differ from baseline in either group. On postoperative imaging more WDP patients had areas of splenic hypoperfusion (p = 0.032). These differences resolved by 3 months after surgery, there were no instances of long term infectious or bleeding complications related to poor splenic function or gastric varices. CONCLUSION: Both WDP and VSDP achieve splenic preservation. Neither technique resulted in clinically apparent spleen related complications. There is no difference in splenic volume and function in the short/long term.

Outcomes of radiofrequency ablation as first-line therapy for hepatocellular carcinoma less than 3 cm in potentially transplantable patients.

BACKGROUND & AIMS: Radiofrequency ablation (RFA) is an effective treatment for single hepatocellular carcinoma (HCC) ≤3 cm. Disease recurrence is common, and in some patients will occur outside transplant criteria. We aimed to assess the incidence and risk factors for recurrence beyond Milan criteria in potentially transplantable patients treated with RFA as first-line therapy. METHODS: We performed a retrospective cohort study of potentially transplantable patients with new diagnoses of unifocal HCC ≤3 cm that underwent RFA as first-line therapy between 2000-2015. We defined potentially transplantable patients as those aged <70 years without any comorbidities that would preclude transplant surgery. Incidence of recurrence beyond Milan criteria was compared across 2 groups according to HCC diameter at the time of ablation: (HCC ≤2 cm vs. HCC >2 cm). Competing risks Cox regression was used to identify predictors of recurrence beyond Milan criteria. RESULTS: We included 301 patients (167 HCC ≤2 cm and 134 HCC >2 cm). Recurrence beyond Milan criteria occurred in 36 (21.6%) and 47 (35.1%) patients in the HCC ≤2 cm and the HCC >2 cm groups, respectively (p = 0.01). The 1-, 3- and 5-year actuarial survival rates after RFA were 98.2%, 86.2% and 79.0% in the HCC ≤2 cm group vs. 93.3%, 77.6% and 70.9% in the HCC >2 cm group (p = 0.01). Tumor size >2 cm (hazard ratio 1.94; 95%CI 1.25-3.02) and alpha-fetoprotein levels at the time of ablation (100-1,000 ng/ml: hazard ratio 2.05; 95%CI 1.10-3.83) were found to be predictors of post-RFA recurrence outside Milan criteria. CONCLUSION: RFA for single HCC ≤3 cm provides excellent short- to medium-term survival. However, we identified patients at higher risk of recurrence beyond Milan criteria. For these patients, liver transplantation should be considered immediately after the first HCC recurrence following RFA. LAY SUMMARY: Radiofrequency ablation and liver transplantation are treatment options for early stages of hepatocellular carcinoma (HCC). After ablation some patients will experience recurrence or metastatic spread of the initial tumor or may develop new tumors within the liver. Despite close follow-up, these recurrences can progress rapidly and exceed transplant criteria, preventing the patient from receiving a transplant. We identified that patients with HCC >2 cm and higher serum alpha-fetoprotein are at greater risk of recurrence beyond the transplant criteria. These data suggest that liver transplantation should be considered immediately after the first HCC recurrence for these patients.

Management and surveillance of non-functional pancreatic neuroendocrine tumours: Retrospective review.

BACKGROUND: /Objective. To determine the outcomes of a non-operative management approach for sporadic, small, non-functional pancreatic neuroendocrine tumours. METHODS: A retrospective chart review of patients with non-functional pancreatic neuroendocrine tumours initially managed non-operatively at a single institution was performed. Patients were identified through a search of radiologic reports, and individuals with ≥2 cross-sectional imaging studies performed >6 months apart from Jan. 1, 2000 to Dec. 31, 2013 were included. Data on tumour size, radiologic characteristics at diagnosis, interval radiologic growth, and surgical outcomes were recorded. RESULTS: Over the thirteen-year study period, 95 patients met inclusion criteria and were followed radiologically for a median of 36 months (18-69 months). Median initial tumour size on first imaging was 14.0 mm (IQR 10-19 mm). Median overall tumour growth rate was 0.03 mm/month (IQR: 0.00-0.14 mm/month). There was no significant relationship between initial tumour size and growth rate for tumours ≤ 2 cm or for lesions between 2 and 4 cm. Thirteen (14%) patients initially managed non-operatively underwent resection during the follow-up period. Reasons for surgery included interval tumour growth, patient anxiety or preference, or diagnostic uncertainty. Median time to surgery was 14 months (IQR 8-19 months). No patients progressed beyond resectability or developed metastatic disease during the observation period. CONCLUSION: For patients with sporadic, small, non-functional pancreatic neuroendocrine tumours, radiologic surveillance appears to be a safe initial approach to management.

The Ubiquitin-Specific Protease 18 Promotes Hepatitis C Virus Production by Increasing Viral Infectivity.

BACKGROUND AND AIMS: Ubiquitin-specific protease 18 (USP18) is involved in immunoregulation and response to interferon- (IFN-) based treatment in patients chronically infected with hepatitis C virus (HCV). We investigated whether and how its upregulation alters HCV infection. METHODS: Overexpression of wild-type (USP18 WT) or catalytically inactive mutant (USP18 C64S) USP18 was examined for effects on HCV replication in the absence and presence of IFNα or IFNλ using both the HCV-infective model and replicon cells. The IFN signaling pathway was assessed via STAT1 phosphorylation (western blot) and downstream ISG expression (real-time PCR). Mechanistic roles were sought by quantifying microRNA-122 levels and J6/JFH1 infectivity of Huh7.5 cells. RESULTS: We found that overexpression of either USP18 WT or USP18 C64S stimulated HCV production and blunted the anti-HCV effect of IFNα and IFNλ in the infective model but not in the replicon system. Overexpressed USP18 showed no effect on Jak/STAT signaling nor on microRNA-122 expression. However, USP18 upregulation markedly increased J6/JFH1 infectivity and promoted the expression of the key HCV entry factor CD81 on Huh7.5 cells. CONCLUSIONS: USP18 stimulates HCV production and blunts the effect of both type I and III IFNs by fostering a cellular environment characterized by upregulation of CD81, promoting virus entry and infectivity.

Renal outcomes following left renal vein harvest for venous reconstruction during pancreas and liver surgery.

BACKGROUND: The left renal vein (LRV) may be used for venous reconstruction during hepato-pancreato-biliary (HPB) surgery, although concerns exist about compromising renal function. This study aimed to determine renal outcomes following LRV harvest during HPB resections. METHODS: Circumferential PV/SMV resections from 2008 to 2014 were included within two groups (LRV harvest, Control). Absolute and change in Creatinine (Cr) and estimated GFR (eGFR), and rates of acute kidney injury (AKI) and chronic kidney disease (CKD), were compared. Multivariate logistic regression analyses were performed. RESULTS: 76 patients were included (LRV n = 17, Control n = 59). Median Cr and eGFR did not change within groups, although change in eGFR differed between groups at postoperative day (POD) 3 (-4.3 vs. 12.8, p = 0.0035) and 7 (-1.8 vs. 12.4, p = 0.0074). AKI occurred more frequently in the LRV group at POD1 (5/17 vs. 4/59, p = 0.023) and POD3 (5/17 vs. 3/59, p = 0012), with no difference in CKD between groups (2/11 vs. 5/33 at 3 months, p = 0.99). LRV harvest was an independent risk factor for AKI at POD1 and POD3, but not thereafter. CONCLUSIONS: Patients who undergo LRV harvest experience a higher rate of AKI in the first three post-operative days. LRV harvest during pancreas resection does not impact on long-term renal function.

Neoadjuvant therapy and major arterial resection for potentially reconstructable arterial involvement by stage 3 adenocarcinoma of the pancreas.

BACKGROUND: Stage 3 pancreatic ductal adenocarcinoma (PDAC) is defined by arterial involvement. This study objective was to evaluate outcomes for patients with stage 3 PDAC with potentially reconstructable arterial involvement, considered for neoadjuvant therapy (NAT) and pancreatic resection, and to compare outcomes following arterial (AR) and non-arterial resection (NAR). METHODS: This study included patients from 2009 to 2016 with biopsy-proven stage 3 PDAC who were offered NAT before surgical exploration. AR was performed if required to achieve R0 resection. Time to event outcomes were analysed from diagnosis date. RESULTS: 87/89 patients (97.8%) received NAT (chemotherapy 41.6%, chemotherapy/radiotherapy 56.2%). 46/89 (51.7%) underwent exploration; 31 underwent resection (AR n = 20, NAR n = 11). AR patients had longer operative time (681 vs. 563 min, p = 0.006) and more blood loss (1600 vs. 575 mL, p = 0.0004), with no difference for blood transfusion, pancreatic fistula, length of stay, reoperation, or mortality. R0 rate was 30/31. Post-resection 90-day mortality was 3.2%. Median overall survival was statistically comparable between the AR and NAR groups (19.7 vs. 28.4 months, p = 0.41). CONCLUSIONS: AR had comparable clinical and oncologic outcomes to NAR. Following careful selection and non-progression after NAT, major AR may cautiously be considered if required to obtain a negative resection margin.

Living Donor Liver Transplantation Using Selected Grafts With 2 Bile Ducts Compared With 1 Bile Duct Does Not Impact Patient Outcome.

The outcome after living donor liver transplantation (LDLT) using grafts with multiple bile ducts (BDs) remains unclear. We analyzed 510 patients who received an adult-to-adult right lobe LDLT between 2000 and 2015 and compared outcome parameters of those receiving grafts with 2 BDs (n = 169) with patients receiving grafts with 1 BD (n = 320). Additionally, patients receiving a graft with 3 BDs (n = 21) were analyzed. Demographic variables and disease severity were similar between the groups. Roux-en-Y reconstruction was significantly more common in the 2 BD group (77% versus 38%; P < 0.001) compared with the 1 BD group. No difference was found in biliary complication rates within 1 year after LDLT (1 BD versus 2 BD groups, 18% versus 21%, respectively; P = 0.46). In the 2 BD group, 82/169 (48.5%) patients were reconstructed with 2 anastomoses. The number of anastomoses did not negatively impact biliary complication rates. Recipients' major complication rate (Clavien ≥ 3b) was similar between both groups (1 BD versus 2 BD groups, 21% versus 24%, respectively; P = 0.36). Furthermore, no difference could be found between the 1 BD, the 2 BD, and the 3 BD groups in the frequency of developing biliary complications within 1 year (18%, 21%, 14%, respectively; P = 0.64), BD strictures (15%, 15%, 5%, respectively; P = 0.42), or BD leaks (10%, 11%, 10%, respectively; P = 0.98). In addition, the 1-year (90% versus 91%), 5-year (82% versus 77%), and 10-year (70% versus 66%) graft survival rates as well as the 1-year (92% versus 93%), 5-year (84% versus 80%), and 10-year (75% versus 76%) patient survival rates were comparable between the 1 BD and the 2 BD groups (P = 0.41 and P = 0.54, respectively). In conclusion, this study demonstrates that selected living donor grafts with 2 BDs can be used safely without negatively impacting biliary complication rates and graft or patient survival rates.

Expanding the donor pool: Donation after circulatory death and living liver donation do not compromise the results of liver transplantation.

Because of the shortfall between the number of patients listed for liver transplantation (LT) and the available grafts, strategies to expand the donor pool have been developed. Donation after circulatory death (DCD) and living donor (LD) grafts are not universally used because of the concerns of graft failure, biliary complications, and donor risks. In order to overcome the barriers for the implementation of using all 3 types of grafts, we compared outcomes after LT of DCD, LD, and donation after brain death (DBD) grafts. Patients who received a LD, DCD, or DBD liver graft at the University of Toronto were included. Between January 2009 through April 2017, 1054 patients received a LT at our center. Of these, 77 patients received a DCD graft (DCD group); 271 received a LD graft (LD group); and 706 received a DBD graft (DBD group). Overall biliary complications were higher in the LD group (11.8%) compared with the DCD group (5.2%) and the DBD group (4.8%; P < 0.001). The 1-, 3-, and 5-year graft survival rates were similar between the groups with 88.3%, 83.2%, and 69.2% in the DCD group versus 92.6%, 85.4%, and 84.7% in the LD group versus 90.2%, 84.2%, and 79.9% in the DBD group (P = 0.24). Furthermore, the 1-, 3-, and 5-year patient survival was comparable, with 92.2%, 85.4%, and 71.6% in the DCD group versus 95.2%, 88.8%, and 88.8% in the LD group versus 93.1%, 87.5%, and 83% in the DBD group (P = 0.14). Multivariate Cox regression analysis revealed that the type of graft did not impact graft survival. In conclusion, DCD, LD, and DBD grafts have similar longterm graft survival rates. Increasing the use of LD and DCD grafts may improve access to LT without affecting graft survival rates. Liver Transplantation 24 779-789 2018 AASLD.

Liver Transplantation is Equally Effective as a Salvage Therapy for Patients with Hepatocellular Carcinoma Recurrence Following Radiofrequency Ablation or Liver Resection with Curative Intent.

BACKGROUND: Liver resection (LR) and radiofrequency ablation (RFA) are curative-intent therapies for early stages of hepatocellular carcinoma (HCC). If HCC recurs, salvage liver transplant (SLT) may constitute a treatment option. OBJECTIVE: We aimed to compare the outcomes of patients transplanted for recurrent HCC after curative-intent therapies with those transplanted as initial therapy. METHODS: We conducted a matched-control (1:1) cohort study comparing patients with HCC treated with primary liver transplant (PLT) with SLT after HCC recurrence. Matching was performed according to the size and number of viable tumors at explant pathology following liver transplant. RESULTS: Between November 1999 and December 2014, 687 patients with HCC were listed for transplant at our institution. A total of 559 patients were transplanted; 509 patients were treated with PLT and 50 patients were treated with SLT for HCC recurrence after primary treatment with LR (n = 25) or RFA (n = 25). The median length of follow-up from transplant was 64 months (0.5-195), and the median time from curative-intent treatment of HCC with RFA or LR to recurrence was 9.5 months (1-36) and 14.5 months (3-143), respectively (p = 0.04). The matched cohort was composed of 48 SLT patients (23 LR and 25 RFA) and 48 PLT patients. The 5-year risk of recurrence after LT was 22% in the PLT group versus 32% in the SLT group (p = 0.53), while the 5-year actuarial patient survival after PLT was 69% versus 70% in the SLT group (p = 1). CONCLUSION: Liver transplant is an effective treatment for patients with HCC recurrence following RFA or LR. Outcomes are similar in both groups.

Live donor liver transplantation with older donors: Increased long-term graft loss due to HCV recurrence.

Using our prospectively collected database all adult hepatitis C virus (HCV)-positive patients receiving an adult-to-adult LDLT between October 2000 and May 2014 were identified. Outcome of LDLT with grafts from younger (<50 years=128) vs older donors (≥50 years=31) was compared. Post-transplant graft function, postoperative complications and incidence of HCV recurrence were evaluated. Long-term graft and patient survival was calculated. No difference in graft function was observed between younger and older grafts. Overall complications were similar between both groups. The severity of complications determined by the Dindo-Clavien score was similar. Graft loss from HCV recurrence was significantly less frequent in younger grafts (18% vs 62%, P = 0.001). Young vs older livers had a trend toward improved 1-, 5-, and 10-year graft survival (89% vs 87%, 77% vs 69%, 70% vs 55%, P = 0.096), while patient survival was comparable between both groups (91% vs 90%, 78% vs 69%, 71% vs 60%, P = 0.25). In conclusion, LDLT with older vs younger grafts are more frequently associated with long-term graft loss due to HCV recurrence. Differences in graft survival might be more prominent with prolonged (≥5-year) follow-up. Living donor-recipient matching is particularly important for younger HCV-positive recipients.

Lipopolysaccharide and Tumor Necrosis Factor Alpha Inhibit Interferon Signaling in Hepatocytes by Increasing Ubiquitin-Like Protease 18 (USP18) Expression.

UNLABELLED: Inflammation may be maladaptive to the control of viral infection when it impairs interferon (IFN) responses, enhancing viral replication and spread. Dysregulated immunity as a result of inappropriate innate inflammatory responses is a hallmark of chronic viral infections such as, hepatitis B virus and hepatitis C virus (HCV). Previous studies from our laboratory have shown that expression of an IFN-stimulated gene (ISG), ubiquitin-like protease (USP)18 is upregulated in chronic HCV infection, leading to impaired hepatocyte responses to IFN-α. We examined the ability of inflammatory stimuli, including tumor necrosis factor alpha (TNF-α), lipopolysaccharide (LPS), interleukin-6 (IL-6) and IL-10 to upregulate hepatocyte USP18 expression and blunt the IFN-α response. Human hepatoma cells and primary murine hepatocytes were treated with TNF-α/LPS/IL-6/IL-10 and USP18, phosphorylated (p)-STAT1 and myxovirus (influenza virus) resistance 1 (Mx1) expression was determined. Treatment of Huh7.5 cells and primary murine hepatocytes with LPS and TNF-α, but not IL-6 or IL-10, led to upregulated USP18 expression and induced an IFN-α refractory state, which was reversed by USP18 knockdown. Liver inflammation was induced in vivo using a murine model of hepatic ischemia/reperfusion injury. Hepatic ischemia/reperfusion injury led to an induction of USP18 expression in liver tissue and promotion of lymphocytic choriomeningitis replication. These data demonstrate that certain inflammatory stimuli (TNF-α and LPS) but not others (IL-6 and IL-10) target USP18 expression and thus inhibit IFN signaling. These findings represent a new paradigm for how inflammation alters hepatic innate immune responses, with USP18 representing a potential target for intervention in various inflammatory states. IMPORTANCE: Inflammation may prevent the control of viral infection when it impairs the innate immune response, enhancing viral replication and spread. Blunted immunity as a result of inappropriate innate inflammatory responses is a common characteristic of chronic viral infections. Previous studies have shown that expression of certain interferon-stimulated genes is upregulated in chronic HCV infection, leading to impaired hepatocyte responses. In this study, we show that multiple inflammatory stimuli can modulate interferon stimulated gene expression and thus inhibit hepatocyte interferon signaling via USP18 induction. These findings represent a new paradigm for how inflammation alters hepatic innate immune responses, with the induction of USP18 representing a potential target for intervention in various inflammatory states.

Mechanism of hard-nanomaterial clearance by the liver.

The liver and spleen are major biological barriers to translating nanomedicines because they sequester the majority of administered nanomaterials and prevent delivery to diseased tissue. Here we examined the blood clearance mechanism of administered hard nanomaterials in relation to blood flow dynamics, organ microarchitecture and cellular phenotype. We found that nanomaterial velocity reduces 1,000-fold as they enter and traverse the liver, leading to 7.5 times more nanomaterial interaction with hepatic cells relative to peripheral cells. In the liver, Kupffer cells (84.8 ± 6.4%), hepatic B cells (81.5 ± 9.3%) and liver sinusoidal endothelial cells (64.6 ± 13.7%) interacted with administered PEGylated quantum dots, but splenic macrophages took up less material (25.4 ± 10.1%) due to differences in phenotype. The uptake patterns were similar for two other nanomaterial types and five different surface chemistries. Potential new strategies to overcome off-target nanomaterial accumulation may involve manipulating intra-organ flow dynamics and modulating the cellular phenotype to alter hepatic cell interactions.

The extended Toronto criteria for liver transplantation in patients with hepatocellular carcinoma: A prospective validation study.

The selection of liver transplant candidates with hepatocellular carcinoma (HCC) relies mostly on tumor size and number. Instead of relying on these factors, we used poor tumor differentiation and cancer-related symptoms to exclude patients likely to have advanced HCC with aggressive biology. We initially reported similar 5-year survival for patients whose tumors exceeded (M+ group) and were within (M group) the Milan criteria. Herein, we validate our original data with a new prospective cohort and report the long-term follow-up (10-years) using an intention-to-treat analysis. The previously published study (cohort 1) included 362 listed (294 transplanted) patients from January 1996 to August 2008. The validation cohort (cohort 2) includes 243 listed (105 M+ group, 76 beyond University of California San Francisco criteria; 210 transplanted) patients from September 2008 to December 2012. Median follow-up from listing was 59.7 (26.8-103) months. For the validation cohort 2, the actuarial survival from transplant for the M+ group was similar to that of the M group at 1 year, 3 years, and 5 years: 94%, 76%, and 69% versus 95%, 82%, and 78% (P = 0.3). For the combined cohorts 1 and 2, there were no significant differences in the 10-year actuarial survival from transplant between groups. On an intention-to-treat basis, the dropout rate was higher in the M+ group and the 5-year and 10-year survival rates from listing were decreased in the M+ group. An alpha-fetoprotein level >500 ng/mL predicted poorer outcomes for both the M and M+ groups. CONCLUSION: Tumor differentiation and cancer-related symptoms of HCC can be used to select patients with advanced HCC who are appropriate candidates for liver transplantation; alpha-fetoprotein level limitations should be incorporated in the listing criteria for patients within or beyond the Milan criteria. (Hepatology 2016;64:2077-2088).