Effects of trientine and penicillamine on intestinal copper uptake: A mechanistic 64 Cu PET/CT study in healthy humans.

BACKGROUND AND AIMS: Trientine (TRI) and D-penicillamine (PEN) are used to treat copper overload in Wilson disease. Their main mode of action is thought to be through the facilitation of urinary copper excretion. In a recent study, TRI was noninferior to PEN despite lower 24-hour urinary copper excretion than PEN. We tested whether TRI and/or PEN also inhibit intestinal copper absorption. APPROACH AND RESULTS: Sixteen healthy volunteers were examined with positron emission tomography (PET)/CT 1 and 15 hours after an oral Copper-64 ( 64 Cu) dose. They then received 7 days of either PEN or TRI (trientine tetrahydrochloride), after which the 64 Cu PET/CT scans were repeated. Venous blood samples were also collected. Pretreatment to posttreatment changes of the hepatic 64 Cu uptake reflect the effect of drugs on intestinal absorption. 64 Cu activity was normalized to dose and body weight and expressed as the mean standard uptake value. TRI (n=8) reduced hepatic 64 Cu activity 1 hour after 64 Cu dose from 6.17 (4.73) to 1.47 (2.97) standard uptake value, p <0.02, and after 15 hours from 14.24 (3.09) to 6.19 (3.43), p <0.02, indicating strong inhibition of intestinal 64 Cu absorption. PEN (n=8) slightly reduced hepatic standard uptake value at 15 hours, from 16.30 (5.63) to 12.17 (1.44), p <0.04. CONCLUSIONS: In this mechanistic study, we show that TRI inhibits intestinal copper absorption, in addition to its cupriuretic effect. In contrast, PEN has modest effects on the intestinal copper absorption. This may explain why TRI and PEN are equally effective although urinary copper excretion is lower with TRI. The study questions whether the same therapeutic targets for 24-hour urinary excretion apply to both drugs.

Effects of tetrathiomolybdate on copper metabolism in healthy volunteers and in patients with Wilson disease.

BACKGROUND & AIMS: In Wilson disease (WD), copper accumulates in the liver and brain causing disease. Bis-choline tetrathiomolybdate (TTM) is a potent copper chelator that may be associated with a lower risk of inducing paradoxical neurological worsening than conventional therapy for neurologic WD. To better understand the mode of action of TTM, we investigated its effects on copper absorption and biliary excretion. METHODS: In a double-blind randomized setting, hepatic 64Cu activity was examined after orally administered 64Cu by PET/CT in 16 healthy volunteers before and after seven days of TTM treatment (15 mg/d) or placebo. Oral 64Cu was administered one hour after the final TTM dose. Changes in hepatic 64Cu activity reflected changes in intestinal 64Cu uptake. Additionally, in four patients with WD, the distribution of 64Cu in venous blood, liver, gallbladder, kidney, and brain was followed after i.v. 64Cu dosing for up to 68 hours before and after seven days of TTM (15 mg/day), using PET/MRI. Increased gallbladder 64Cu activity was taken as evidence of increased biliary 64Cu excretion. RESULTS: In healthy volunteers, TTM reduced intestinal 64Cu uptake by 82% 15 hours after the oral 64Cu dose. In patients with WD, gallbladder 64Cu activity was negligible before and after TTM, while TTM effectively retained 64Cu in the blood, significantly reduced hepatic 64Cu activity at all time-points and significantly reduced cerebral 64Cu activity two hours after the intravenous 64Cu dose. CONCLUSIONS: While we did not show an increase in biliary excretion of 64Cu following TTM administration, we demonstrated that TTM effectively inhibited most intestinal 64Cu uptake and retained 64Cu in the blood stream, limiting the exposure of organs like the liver and brain to 64Cu. IMPACT AND IMPLICATIONS: Bis-choline tetrathiomolybdate (TTM) is an investigational copper chelator being developed for the treatment of Wilson disease. In animal models of Wilson disease, TTM has been shown to facilitate biliary copper excretion. In the present human study, TTM surprisingly did not facilitate biliary copper excretion but instead reduced intestinal copper uptake to a clinically significant degree. Our study builds on our understanding of human copper metabolism and the mechanism of action of TTM.

Distribution of non-ceruloplasmin-bound copper after i.v. 64Cu injection studied with PET/CT in patients with Wilson disease.

Background & Aims: In Wilson disease (WD), copper accumulation and increased non-ceruloplasmin-bound copper in plasma lead to liver and brain pathology. To better understand the fate of non-ceruloplasmin-bound copper, we used PET/CT to examine the whole-body distribution of intravenously injected 64-copper (64Cu). Methods: Eight patients with WD, five heterozygotes, and nine healthy controls were examined by dynamic PET/CT for 90 min and static PET/CT up to 20 h after injection. We measured 64Cu activity in blood and tissue and quantified the kinetics by compartmental analysis. Results: Initially, a large fraction of injected 64Cu was distributed to extrahepatic tissues, especially skeletal muscle. Thus, across groups, extrahepatic tissues accounted for 45-58% of the injected dose (%ID) after 10 min, and 45-55% after 1 h. Kinetic analysis showed rapid exchange of 64Cu between blood and muscle as well as adipose tissue, with 64Cu retention in a secondary compartment, possibly mitochondria. This way, muscle and adipose tissue may protect the brain from spikes in non-ceruloplasmin-bound copper. Tiny amounts of cerebral 64Cu were detected (0.2%ID after 90 min and 0.3%ID after 6 h), suggesting tight control of cerebral copper in accordance with a cerebral clearance that is 2-3-fold lower than in muscle. Compared to controls, patients with WD accumulated more hepatic copper 6-20 h after injection, and also renal copper at 6 h. Conclusion: Non-ceruloplasmin-bound copper is initially distributed into a number of tissues before being redistributed slowly to the eliminating organ, the liver. Cerebral uptake of copper is extremely slow and likely highly regulated. Our findings provide new insights into the mechanisms of copper control. Impact and implications: Maintaining non-ceruloplasmin-bound copper within the normal range is an important treatment goal in WD as this "free" copper is considered toxic to the liver and brain. We found that intravenously injected non-ceruloplasmin-bound copper quickly distributed to a number of tissues, especially skeletal muscle, subcutaneous fat, and the liver, while uptake into the brain was slow. This study offers new insights into the mechanisms of copper control, which may encourage further research into potential new treatment targets. Clinical trial number: 2016-001975-59.

Histological and serological features of acute liver injury after SARS-CoV-2 vaccination.

Background & Aims: Liver injury with autoimmune features after vaccination against severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) is increasingly reported. We investigated a large international cohort of individuals with acute hepatitis arising after SARS-CoV-2 vaccination, focusing on histological and serological features. Methods: Individuals without known pre-existing liver diseases and transaminase levels ≥5x the upper limit of normal within 3 months after any anti-SARS-CoV-2 vaccine, and available liver biopsy were included. Fifty-nine patients were recruited; 35 females; median age 54 years. They were exposed to various combinations of mRNA, vectorial, inactivated and protein-based vaccines. Results: Liver histology showed predominantly lobular hepatitis in 45 (76%), predominantly portal hepatitis in 10 (17%), and other patterns in four (7%) cases; seven had fibrosis Ishak stage ≥3, associated with more severe interface hepatitis. Autoimmune serology, centrally tested in 31 cases, showed anti-antinuclear antibody in 23 (74%), anti-smooth muscle antibody in 19 (61%), anti-gastric parietal cells in eight (26%), anti-liver kidney microsomal antibody in four (13%), and anti-mitochondrial antibody in four (13%) cases. Ninety-one percent were treated with steroids ± azathioprine. Serum transaminase levels improved in all cases and were normal in 24/58 (41%) after 3 months, and in 30/46 (65%) after 6 months. One patient required liver transplantation. Of 15 patients re-exposed to SARS-CoV-2 vaccines, three relapsed. Conclusion: Acute liver injury arising after SARS-CoV-2 vaccination is frequently associated with lobular hepatitis and positive autoantibodies. Whether there is a causal relationship between liver damage and SARS-CoV-2 vaccines remains to be established. A close follow-up is warranted to assess the long-term outcomes of this condition. Impact and implications: Cases of liver injury after vaccination against severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) have been published. We investigated a large international cohort of individuals with acute hepatitis after SARS-CoV-2 vaccination, focusing on liver biopsy findings and autoantibodies: liver biopsy frequently shows inflammation of the lobule, which is typical of recent injury, and autoantibodies are frequently positive. Whether there is a causal relationship between liver damage and SARS-CoV-2 vaccines remains to be established. Close follow-up is warranted to assess the long-term outcome of this condition.

Highly Increased Levels of Inter-α-inhibitor Heavy Chain 4 (ITIH4) in Autoimmune Cholestatic Liver Diseases.

Background and Aims: There is an unmet need for new biomarkers to improve diagnostics and prognostics in primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC). Inter-α-inhibitor heavy chain 4 (ITIH4) is an abundant, liver-produced protein, and its synthesis may be altered in liver diseases. We investigated whether ITIH4 plasma concentrations were affected in PBC and PSC patients. Methods: We developed an immunoassay specific for ITIH4 and determined ITIH4 plasma concentrations in 66 PBC, 126 PSC, 92 autoimmune hepatitis (AIH), 67 chronic hepatitis C (CHC), 33 alcoholic hepatitis (AH) patients and 138 healthy controls (HCs). Hepatic ITIH4 expression was investigated by immunohistochemistry in PBC. Results: The mean plasma concentration of ITIH4 was almost doubled in PBC [409 µg/mL (95% CI: 388-431)] and 35% higher in PSC [308 µg/mL, (95% CI: 296-319)] compared with HCs [226 µg/mL (95% CI: 221-231); p<0.001]. In PBC patients, ITIH4 correlated with IgM (rho=0.49, p<0.001). Responders to ursodeoxycholic acid treatment (UDCA) had lower levels of ITIH4 than incomplete responders [395 µg/mL (95% CI: 364-425)] vs. 460 µg/mL (95% CI: 421-498); p=0.02]. Four weeks of UDCA treatment had no effect (p=0.19). Increased ITIH4 immunohistochemical staining was seen in a liver biopsy from a PBC patient. ITIH4 levels in AIH [224 µg/mL (95% CI: 208-241)] and HCs were similar (p=0.8). ITIH4 levels were lower in AH [199 µg/mL (95% CI: 175-223)] and CHC [202 µg/mL (192-212)] patients than in HCs (p<0.05). Conclusions: The plasma concentration of ITIH4 was highly elevated in patients with PBC and PSC, suggesting that ITIH4 should be further investigated as a biomarker in cholestatic liver disease.

Psychometric methods for diagnosing and monitoring minimal hepatic encephalopathy -current validation level and practical use.

Hepatic encephalopathy (HE) is cerebral dysfunction caused by liver failure and inflicts 30-40% of patients with liver cirrhosis during their disease course. Clinically manifest HE is often preceded by minimal HE (MHE) - a clinically undetectable cognitive disturbance closely associated with loss of quality of life. Accordingly, detecting and treating MHE improve the patients' daily functioning and prevent HE-related hospital admissions. The scope of this review article is to create an overview of the validation level and usage of psychometric tests used to detect MHE: Portosystemic hepatic encephalopathy test, continuous reaction time test, Stroop EncephalApp, animal naming test, critical flicker frequency test, and inhibitory control test. Our work is aimed at the clinician or scientist who is about to decide on which psychometric test would fit best in their clinic, cohort, or study. First, we outline psychometric test validation obstacles and requirements. Then, we systematically approach the literature on each test and select well-conducted studies to answer the following questions:• Which percentage of patients with cirrhosis does the test deem as having MHE?• Is the test able to predict clinically manifest HE?• Is there a well-known test-retest variation and inter-observer variation?• Is the test able to detect a treatment response?• Is the test result affected by age, educational level, gender, or comorbidities?

The pathophysiology of Wilson's disease visualized: A human 64 Cu PET study.

BACKGROUND AND AIMS: Wilson's disease (WD) is a genetic disease with systemic accumulation of copper that leads to symptoms from the liver and brain. However, the underlying defects in copper transport kinetics are only partly understood. We sought to quantify hepatic copper turnover in patients with WD compared with heterozygote and control subjects using PET with copper-64 (64 Cu) as a tracer. Furthermore, we assessed the diagnostic potential of the method. APPROACH AND RESULTS: Nine patients with WD, 5 healthy heterozygote subjects, and 8 healthy controls were injected with an i.v. bolus of 64 Cu followed by a 90-min dynamic PET scan of the liver and static whole-body PET/CT scans after 1.5, 6, and 20 h. Blood 64 Cu concentrations were measured in parallel. Hepatic copper retention and redistribution were evaluated by standardized uptake values (SUVs). At 90 min, hepatic SUVs were similar in the three groups. In contrast, at 20 h postinjection, the SUV in WD patients (mean ± SEM, 31 ± 4) was higher than in heterozygotes (24 ± 3) and controls (21 ± 4; p < 0.001). An SUV-ratio of hepatic 64 Cu concentration at 20 and 1.5 h completely discriminated between WD patients and control groups (p < 0.0001; ANOVA). By Patlak analysis of the initial 90 min of the PET scan, the steady-state hepatic clearance of 64 Cu was estimated to be slightly lower in patients with WD than in controls (p = 0.04). CONCLUSIONS: 64 Cu PET imaging enables visualization and quantification of the hepatic copper retention characteristic for WD patients. This method represents a valuable tool for future studies of WD pathophysiology, and may assist the development of therapies, and accurate diagnosis.

ATP7B variant spectrum in a French pediatric Wilson disease cohort.

BACKGROUND/AIM: The spectrum of ATP7B variants varies significantly according to geographic distribution, and there is insufficient data on the variants observed in the French population. METHODS: Clinical data of 113 children included in the French WD national registry were gathered from March 01, 1995 to July 01, 2020. Data included epidemiological, clinical, laboratory, genetics. RESULTS: Diagnosis was made at a mean age of 11.0 ± 4.1 years (range 1-18 years). At diagnosis, 91 patients (79.8 %) had hepatic manifestations, 18 (15.8 %) presented neurological manifestations, and 4 patients (3.5 %) were asymptomatic. Only 29 patients (25 %) were homozygous for a variant. We have found a total of 102 different variants including 14 novel variants. Recurrent variant p.His1069Gln was the most prevalent, n = 31 alleles (14,2%), with only seven homozygous; in contrast 55% of variants are identified in only one family. 45% were truncating variants. In respect of mutated exon, the three most prevalent were exon 14 (16.5%), exon 8 (13.8%), and exon 3 (11.5%). When considering patients with two Nonsense / Frameshift variants as a group and those with two Missense variants, we found significantly lower ceruloplasmin for the former: 2.8 ± 0.7 mg/dl vs 8.4 ± 5mg/dl (p<0.05). CONCLUSION: p.His1069Gln is the most frequent variant (14,2%) and exons 14, 8, and 2 of the ATP7B gene account for 41.7% of total variants. However, there is significant heterogeneity in the French population concerning the other ATP7B variants. Nonsense / Frameshift variants were associated with lower ceruloplasmin levels.

Cognitive impairment in stable Wilson disease across phenotype.

In Wilson disease (WD), mutations in the gene encoding the ATP7B copper transport protein causes accumulation of copper especially in liver and brain. WD typically presents with hepatic and/or neuropsychiatric symptoms. Impaired cognition is a well-described feature in patients with neurological WD, while the reports on cognition in hepatic WD patients are fewer and less conclusive. We examined cognition in a cohort of WD patients with both phenotypes. In this cross-sectional pilot study, we investigated cognition in 28 stable Danish WD patients by the PortoSystemic Encephalopathy (PSE) and the Continuous Reaction Time (CRT) tests. Half of the patients were female, and their median age was 35.5 years (IQR 24.5). Their phenotype was hepatic in 14 (50%), neurologic in 10 (36%) and mixed in 4 (14%). The duration of treatment was > 2 year in all patients, and their condition was stable as judged by urinary copper excretion, liver enzymes, and clinical assessment. The hepatic patients did not show signs of liver failure. In total, 16 (57%) patients performed worse than normal in the PSE and/or the CRT tests. The two tests were correlated (rho = 0.60, p = 0.0007), but neither correlated with phenotype, MELD-, Child-Pugh score, 24 h-U-Cu, or treatment type. Measurable cognitive impairment was present in more than half of the stable WD patients independent of phenotype. Thus, our data questions the existence of a purely hepatic phenotype.

Designing Clinical Trials in Wilson's Disease.

BACKGROUND AND AIMS: Wilson's disease (WD) is an autosomal-recessive disorder caused by ATP7B gene mutations leading to pathological accumulation of copper in the liver and brain. Adoption of initial treatments for WD was based on empirical observations. These therapies are effective, but there are still unmet needs for which treatment modalities are being developed. An increase of therapeutical trials is anticipated. APPROACH AND RESULTS: The first Wilson Disease Aarhus Symposium (May 2019) included a workshop on randomized clinical trial design. The authors of the article were organizers or presented during this workshop, and this article presents their consensus on the design of clinical trials for WD, addressing trial population, treatment comparators, inclusion and exclusion criteria, and treatment endpoints. To achieve adequate recruitment of patients with this rare disorder, the study groups should include all clinical phenotypes and treatment-experienced as well as treatment-naïve patients. CONCLUSIONS: The primary study endpoint should be clinical or a composite endpoint until appropriate surrogate endpoints are validated. Standardization of clinical trials will permit pooling of data and allow for better treatment comparisons, as well as reduce the future numbers of patients needed per trial.

Randomised clinical study: acute effects of metformin versus placebo on portal pressure in patients with cirrhosis and portal hypertension.

BACKGROUND: Portal hypertension is the main determinant of clinical decompensation in patients with liver cirrhosis. In preclinical data metformin lowers portal pressure, but there are no clinical data for this beneficial effect. AIMS: To investigate the acute effects of metformin on hepatic venous pressure gradient (HVPG) and liver perfusion. METHODS: In a randomised, double-blinded study design, we investigated 32 patients with cirrhosis before and 90 minutes after ingestion of 1000-mg metformin (n = 16) or placebo (n = 16). Liver vein catherisation was performed to evaluate HVPG and indocyanine green (ICG) infusion for investigation of hepatic blood flow. RESULTS: The mean relative change in HVPG was -16% (95% CI: -28% to -4%) in the metformin group compared with 4% (95% CI: -6% to 14%) in the placebo group (time × group interaction, P = 0.008). In patients with baseline HVPG ≥12 mm Hg clinically significant improvements in HVPG (HVPG <12 mm Hg or a >20% reduction in HVPG) were observed in 46% (6/13) of metformin-treated and in 8% (1/13) of placebo-treated patients (P = 0.07). There were no changes or differences in systemic blood pressure, heart rate, hepatic plasma and blood flow, hepatic ICG clearance, hepatic O2 uptake or inflammation markers between groups. CONCLUSIONS: A single oral metformin dose acutely reduces HVPG in patients with portal hypertension without affecting systemic or liver hemodynamics or inflammatory biomarkers. This offers a promising perspective of a safe and inexpensive treatment option that should be investigated in larger-scale clinical studies with long-term outcomes in patients with cirrhosis and portal hypertension.

Diminished Non-Classical Monocytes in the Blood Associate with Disease Severity in Alcoholic Hepatitis.

OBJECTIVE: Alcoholic hepatitis (AH) holds a high mortality, and vast macrophage infiltration of the liver is involved in the progressive liver injury. No efficient medical treatment exists, and macrophages may be a future treatment target. Here, we examine associations between non-classical monocyte subsets and cell surface markers of migration with disease activity in patients with severe AH. METHODS: We analyzed samples from two cohorts of patients with AH. Cohort 1 included 15 AH patients, followed for 30 days, and 8 healthy controls (HCs). Cohort 2 included 23 AH patients, followed for 90 days, and 9 HCs. Peripheral blood mononuclear cells (PBMCs) from both cohorts were analyzed by flow cytometry. Liver biopsies from cohort 2 were analyzed by RNA sequencing. RESULTS: Circulating non-classical monocytes in all but absent in patients with AH compared to HC in both cohorts (both p<0.0001). The frequency of non-classical monocytes was significantly associated with Maddrey's discriminant function (mDF) (r=-0.79, p=0.0008, cohort 1), Child-Pugh score (CP) (r=-0.56, p=0.03, cohort 1), Model for End-Stage Liver Disease (MELD) (r=-0.54, p=0.02, cohort 2) and C-reactive protein (CRP) (r=-0.51, p=0.027, cohort 2). The surface expression of CD11b was increased on non-classical monocytes in patients with AH compared to HC (p<0.0001) (cohort 1). The mRNA expression of CD11b was increased in liver biopsies in patients with AH compared to HC (cohort 2) (p<0.0001). CONCLUSION: In this study, we describe an almost complete depletion of circulating non-classical monocytes in the blood in two independent cohorts of patients with AH, which may be associated with a possible harmful recruitment of these cells to the liver. These results contribute to a better understanding of the disease, which hopefully can lead to therapies that target the acute inflammatory response leading to severe AH.

No Effect in Alcoholic Hepatitis of Gut-Selective, Broad-Spectrum Antibiotics on Bacterial Translocation or Hepatic and Systemic Inflammation.

INTRODUCTION: In alcoholic hepatitis (AH), translocation of gut bacteria may drive hepatic macrophage activation and systemic inflammation. We investigated the effect of oral non-absorbable, broad-spectrum antibiotic treatment on bacterial translocation and liver and systemic inflammation in AH. METHODS: We consecutively recruited 31 patients with AH. Fourteen were given vancomycin 500 mg, gentamycin 40 mg, and meropenem 500 mg once daily for 7 days. Seventeen patients were a reference group receiving standard-of-care. Circulating markers of bacterial translocation and inflammation were measured at baseline, by day 7 and 90. Gut bacteriome profiling was performed before the intervention and at day 7. RESULTS: At study entry, blood lipopolysaccharide-binding protein was multifold higher than normal, remained unchanged at day 7, but decreased at day 90 (P < 0.001) with no difference between the study groups. The macrophage activation markers sCD163 and sCD206 showed the same pattern (P < 0.001, day 90), still without group differences. The systemic inflammation markers tumor necrosis factor-alpha, interleukin (IL)-6, IL-8, and IL-10 showed similar dynamics without group differences. There was no difference in 90-day mortality (total of 6 deaths) between the groups. The remnant gut bacteriome was markedly diversified by the intervention with growth of bacterial species rare for human flora. DISCUSSION: In patients with AH, gut-targeted antibiotic treatment does not change markers of bacterial translocation and liver and systemic inflammation. This suggests that bacterial translocation is less important once the inflammatory process is established or that bacteriome reduction is less important than composition.

Low Interleukin-22 Binding Protein Is Associated With High Mortality in Alcoholic Hepatitis and Modulates Interleukin-22 Receptor Expression.

INTRODUCTION: In alcoholic hepatitis (AH), high interleukin (IL)-22 production is associated with disease improvement, purportedly through enhanced infection resistance and liver regeneration. IL-22 binding protein (BP) binds and antagonizes IL-22 bioactivity, but data on IL-22BP in liver disease suggest a complex interplay. Despite the scarcity of human data, IL-22 is in clinical trial as treatment of AH. We, therefore, in patients with AH, described the IL-22 system focusing on IL-22BP and associations with disease course, and mechanistically pursued the human associations in vitro. METHODS: We prospectively studied 41 consecutive patients with AH at diagnosis, days 7 and 90, and followed them for up to 1 year. We measured IL-22 pathway proteins in liver biopsies and blood and investigated IL-22BP effects on IL-22 in hepatocyte cultures. RESULTS: IL-22BP was produced in the gut and was identifiable in the patients with AH' livers. Plasma IL-22BP was only 50% of controls and the IL-22/IL-22BP ratio thus elevated. Consistently, IL-22-inducible genes were upregulated in AH livers at diagnosis. Low plasma IL-22BP was closely associated with high 1-year mortality. In vitro, IL-22 stimulation reduced IL-22 receptor (R) expression, but coincubation with IL-22BP sustained IL-22R expression. In the AH livers, IL-22R mRNA expression was similar to healthy livers, although IL-22R liver protein was higher at diagnosis. DISCUSSION: Plasma IL-22BP was associated with an adverse disease course, possibly because its low level reduces IL-22R expression so that IL-22 bioactivity was reduced. This suggests the IL-BP interplay to be central in AH pathogenesis, and in future treatment trials (see Visual abstract, Supplementary Digital Content 5, http://links.lww.com/CTG/A338).

The macrophage activation marker soluble CD163 is elevated and associated with liver disease phenotype in patients with Wilson's disease.

BACKGROUND: Macrophages play a significant role in liver disease development and progression. The macrophage activation marker soluble (s)CD163 is associated with severity and prognosis in a number of different acute and chronic liver diseases but has been only sparsely examined in Wilson's disease (WD). We investigated sCD163 levels in patients with acute and chronic WD and hypothesized associations with liver disease phenotype and biochemical markers of liver injury. METHODS: We investigated sCD163 in two independent cohorts of WD patients: 28 patients with fulminant WD from the US Acute Liver Failure (ALF) Study Group registry and 147 patients with chronic disease from a German WD registry. We included a control group of 19 healthy individuals. Serum sCD163 levels were measured by ELISA. Liver CD163 expression was determined by immunohistochemistry. RESULTS: In the ALF cohort, median sCD163 was 10-fold higher than in healthy controls (14.6(2.5-30.9) vs. 1.5(1.0-2.7) mg/L, p < 0.001). In the chronic cohort, median sCD163 was 2.6(0.9-24.9) mg/L. There was no difference in sCD163 according to subgroups based on initial clinical presentation, i.e. asymptomatic, neurologic, hepatic, or mixed. Patients with cirrhosis at the time of diagnosis had higher sCD163 compared with those without cirrhosis (3.0(1.2-24.9) vs. 2.3(0.9-8.0) mg/L, p < 0.001); and both cohorts significantly lower than the ALF patients. Further, sCD163 correlated positively with ALT, AST, GGT and INR (rho = 0.27-0.53); and negatively with albumin (rho = - 0.37), (p ≤ 0.001, all). We observed immunohistochemical CD163 expression in liver tissue from ALF patients. CONCLUSIONS: Although sCD163 is not specific for WD, it was elevated in WD patients, especially in those with ALF. Further, sCD163 was higher in patients with cirrhosis compared to patients without cirrhosis and associated with biochemical markers of liver injury and hepatocellular function. Thus, macrophage activation is evident in WD and associates with liver disease phenotype and biochemical parameters of liver disease. Our findings suggest that sCD163 may be used as a marker of liver disease severity in WD patients.

Intravenous and oral copper kinetics, biodistribution and dosimetry in healthy humans studied by [64Cu]copper PET/CT.

PURPOSE: Copper is essential for enzymatic processes throughout the body. [64Cu]copper (64Cu) positron emission tomography (PET) has been investigated as a diagnostic tool for certain malignancies, but has not yet been used to study copper homeostasis in humans. In this study, we determined the hepatic removal kinetics, biodistribution and radiation dosimetry of 64Cu in healthy humans by both intravenous and oral administration. METHODS: Six healthy participants underwent PET/CT studies with intravenous or oral administration of 64Cu. A 90 min dynamic PET/CT scan of the liver was followed by three whole-body PET/CT scans at 1.5, 6, and 20 h after tracer administration. PET data were used for estimation of hepatic kinetics, biodistribution, effective doses, and absorbed doses for critical organs. RESULTS: After intravenous administration, 64Cu uptake was highest in the liver, intestinal walls and pancreas; the gender-averaged effective dose was 62 ± 5 µSv/MBq (mean ± SD). After oral administration, 64Cu was almost exclusively taken up by the liver while leaving a significant amount of radiotracer in the gastrointestinal lumen, resulting in an effective dose of 113 ± 1 µSv/MBq. Excretion of 64Cu in urine and faeces after intravenous administration was negligible. Hepatic removal kinetics showed that the clearance of 64Cu from blood was 0.10 ± 0.02 mL blood/min/mL liver tissue, and the rate constant for excretion into bile or blood was 0.003 ± 0.002 min- 1. CONCLUSION: 64Cu biodistribution and radiation dosimetry are influenced by the manner of tracer administration with high uptake by the liver, intestinal walls, and pancreas after intravenous administration, while after oral administration, 64Cu is rapidly absorbed from the gastrointestinal tract and deposited primarily in the liver. Administration of 50 MBq 64Cu yielded images of high quality for both administration forms with radiation doses of approximately 3.1 and 5.7 mSv, respectively, allowing for sequential studies in humans. TRIAL REGISTRATION NUMBER: EudraCT no. 2016-001975-59. Registration date: 19/09/2016.