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Although a good genotype-phenotype correlation has not been established in Wilson disease (WD), patients with loss-of-function (LOF) ATP7B variants demonstrate different clinical and biochemical characteristics. We aim to describe long-term treatment outcomes in the chronic liver disease (CLD) phenotype and evaluate an association with LOF variants.This was a single-center retrospective review of WD patients with at least 1 variant in ATP7B. Demographic, biochemical, genetic, and clinical parameters were obtained. The composite clinical endpoint of liver transplantation or death was used for probands with CLD phenotype on chelators.Of 117 patients with hepatic WD: 71 had CLD, 27 had fulminant hepatic failure requiring urgent liver transplantation, and 19 were diagnosed through family screening. Median age at diagnosis was 13.1 (interquartile range, 9.7-17.6) years. In total, 91 variants in ATP7B were identified in the study population. At least 1 LOF variant was present in 60 (51.3%) patients. During median follow-up of 10.7 (interquartile range, 6.7-18.9) years, 10 (14.1%) of the probands with CLD reached the composite endpoint. There was a worse transplant-free survival for patients prescribed chelation therapy in patients with at least 1 LOF variant (P = .03).Patients with WD and CLD phenotype on chelators, who have at least 1 LOF variant in ATP7B, have a worse prognosis during long-term follow up. This subgroup of patients requires close monitoring for signs of progressive liver disease. Sequencing of ATP7B may be used in the diagnosis of WD, and in addition, it may provide useful prognostic information for patients with hepatic WD.

BackgroundCatatonia, a severe neuropsychiatric syndrome, has few studies of sufficient scale to clarify its epidemiology or pathophysiology. We aimed to characterise demographic associations, peripheral inflammatory markers and outcome of catatonia.MethodsElectronic healthcare records were searched for validated clinical diagnoses of catatonia. In a case–control study, demographics and inflammatory markers were compared in psychiatric inpatients with and without catatonia. In a cohort study, the two groups were compared in terms of their duration of admission and mortality.ResultsWe identified 1456 patients with catatonia (of whom 25.1% had two or more episodes) and 24 956 psychiatric inpatients without catatonia. Incidence was 10.6 episodes of catatonia per 100 000 person-years. Patients with and without catatonia were similar in sex, younger and more likely to be of Black ethnicity. Serum iron was reduced in patients with catatonia [11.6 v. 14.2 μmol/L, odds ratio (OR) 0.65 (95% confidence interval (CI) 0.45–0.95), p = 0.03] and creatine kinase was raised [2545 v. 459 IU/L, OR 1.53 (95% CI 1.29–1.81), p < 0.001], but there was no difference in C-reactive protein or white cell count. N-Methyl-d-aspartate receptor antibodies were significantly associated with catatonia, but there were small numbers of positive results. Duration of hospitalisation was greater in the catatonia group (median: 43 v. 25 days), but there was no difference in mortality after adjustment.ConclusionsIn the largest clinical study of catatonia, we found catatonia occurred in approximately 1 per 10 000 person-years. Evidence for a proinflammatory state was mixed. Catatonia was associated with prolonged inpatient admission but not with increased mortality.

Objective Hepatocellular carcinoma (HCC) is a complication of the common genetic condition hereditary hemochromatosis (HH). It is unknown whether HH as an etiology of liver disease impacts the outcome. We compared the results of liver transplantation (LT), surgical resection and locoregional therapies in a matched cohort study and investigated whether HH as an etiology has an impact on survival. Materials and methods Consecutive patients with HH and HCC (2000 to 2015) were compared with age, sex and Barcelona Clinic Liver Cancer (BCLC) stage-matched non-HH HCC cases. Patients were offered curative or noncurative treatment according to BCLC stage and Milan criteria. The primary endpoint was all-cause mortality. Results A total of 102 patients (52 HH; total cohort median age: 67 [44 to 78] y, 97% male, Model for End-stage Liver Disease: 9 [5 to 31]) were studied with a median follow-up of 22 (3 to 126) months. Of the HH cases, the median serum ferritin at diagnosis of HCC was 326 (27 to 5718) μg/L and α-fetoprotein 33 (2 to 197,926) kIU/L. Five-year survival for HH patients receiving curative therapy was 77% (80% for LT, 67% for resection/radiofrequency ablation), and 15% (23% for transarterial chemoembolization) for those undergoing noncurative therapy. Survival for HH patients compared with controls was similar (hazard ratio=0.949; P=0.839). On multivariate Cox regression survival analysis, BCLC stage, and diagnosis of ischemic heart disease (but not HH diagnosis) were independently associated with reduced survival. Conclusions Patients with HCC and HH can achieve comparable survival rates following curative or LRT modalities to other liver diseases. The BCLC staging system accurately stratifies survival and excellent 5-year survival is possible following LT in selected patients.

We explored transient elastography (TE) and enhanced liver fibrosis (ELF™ ) score with standard markers of liver function to assess liver damage in 193 well patients with sickle cell disease (SCD). Patients with HbSS or HbSβ0 thalassaemia (sickle cell anaemia, SCA; N = 134), had significantly higher TE results and ELF scores than those with HbSC (N = 49) disease (TE, 6·8 vs. 5·3, P

Objectives/AimsCatatonia is an important neuropsychiatric disorder with a high morbidity and mortality. However, due to a perception that it is very infrequent and because of the acuity of the patients, it has remained poorly studied and research has often been confined to small groups.We hypothesised that: catatonia would remain a significant clinical problem; catatonic patients would have a longer duration of admission and higher mortality; serum iron would be reduced, reflecting a systemic inflammatory response, and high rates of NMDA receptor antibody serum positivity would be observed.MethodsThis was a prospective cohort study that included patients in a large mental health trust who were diagnosed with catatonia between 2007 and 2016. We used the Clinical Records Interactive Search (CRIS) system hosted at the NIHR Maudsley Biomedical Research Centre to search the clinical records for patients with catatonia. An initial free-text search was refined by use of a natural language processing app. The results of the app were validated by three of the authors, who included patients in the analysis only if a clinician had made a diagnosis of catatonia and two or more items of the Bush-Francis Catatonia Screening Instrument were in evidence.Demographic, clinical and blood-based markers could then be extracted for these patients and compared, where relevant, to non-catatonic psychiatric patients.Results1,456 patients with catatonia (of whom 787 were psychiatric inpatients) and 37,456 psychiatric inpatient controls were identified. There was no evidence for a reduction in the rate of catatonia over time. Patients with catatonia were younger than the controls by 2.52 years (95% CI 1.30 to 3.73) and similar in gender composition. Patients with catatonia were more likely to be black (53.5% vs 24.5%, pConclusionsThis is the largest study of catatonia to date. There is evidence that catatonia is not dying out and confers high morbidity but without affecting mortality. The innate immune system does not seem to be activated, but NMDA receptor antibodies are present at higher rates than in psychiatric controls. We demonstrate that catatonia remains an important clinical problem and may be associated with neuroimmunological dysfunction.

Recent data suggest an association of serum ferritin (SF) with waiting list (WL) and postliver transplant (LT) outcomes. To assess the predictive capacity of SF on pre- and post-LT outcomes, and to identify whether recipient or donor liver siderosis is associated with post-LT survival; a retrospective analysis of 1079 patients assessed for first LT, 2000–2007 was performed. Iron deposition in the liver tissue was assessed using a semi-quantitative grading system. Median age was 54 (18–82) years and 67% were male. Seventeen per cent had hepatocellular carcinoma (HCC). Median Model for End-stage Liver Disease MELD score was 14 (6–40), ferritin was 174 μg/l (4–4597) with 36.5% had a SF ≥ μg/l. Age (OR = 1.028) and MELD score (OR = 1.158) were independently associated with WL mortality (P

BACKGROUND: Hepcidin is a peptide hormone belonging to the defensin family of cationic antimicrobial molecules that has an essential role in systemic iron homeostasis. The peptide is synthesised by hepatocytes and transported in the circulation to target tissues where it regulates the iron export function of the ferrous iron permease, ferroportin. In the brain hepcidin protein has been identified using immuno-histochemistry and mRNA by real-time PCR but not by in situ hybridisation raising the question of whether there is measurable transcription of the hepcidin gene in the central nervous system. Alternatively hepcidin could be transported as a hormone to the brain via the circulation. RESULTS: By RT-PCR hepcidin mRNA was present at low level throughout normal rat brain while in situ hybridisation to detect low-abundant mRNA revealed that transcripts were restricted to endothelium of blood vessels and choroid plexus. In contrast, hepcidin protein analysed by immuno-histochemistry was highly expressed in blood vessels, in endothelium and in pericytes. Hepcidin was also present in glial cells and in the olfactory bulb, sub-ventricular zone and dentate gyrus, areas where neurogenesis and synaptic plasticity are maintained throughout adult life. The hepcidin species identified by Western blotting in sub-ventricular zone, cortex and hippocampus migrated as a ~2.8 kDa band, identical in size to hepcidin present in normal rat serum suggesting that hepcidin in brain was the full-length biologically active 25 amino acid peptide. Hepcidin co-localised with ferroportin in ependymal cells of the sub-ventricular zone and in the corpus callosum consistent with a regulatory role in iron metabolism at these sites. CONCLUSIONS: Hepcidin protein was widely expressed in brain parenchyma while levels of hepcidin gene transcription appeared to be below the limits of detection of the in situ hybridisation probes. This disparity suggests that not all hepcidin in the brain is transcribed in situ and may originate in part outside the brain. The properties of hepcidin as a cationic peptide hormone are reflected in the finding of hepcidin in the walls of blood vessels and in pericytes and glia, cells that may be involved in transporting the peptide into brain interstitium.

GATA-6 has been implicated in the regulation of myocardial differentiation during cardiogenesis. To determine how its expression is controlled, we have characterized the human and mouse genes. We have mapped their transcriptional start sites and demonstrate that two alternative promoters and 5' noncoding exons are utilized. Both transcript isoforms are expressed in the same tissue-specific and developmental stage-specific pattern, and their ratio appears similar wherever examined. The more upstream noncoding exon showed a substantial degree of homology between the two mammalian species, suggesting a conserved regulatory function. Moreover, in transfection assays we show that elements within this exon act to promote its transcription. Positive regulatory elements that effect transcription from the more downstream exon were not apparent in this assay, revealing a regulatory distinction between the two promoters. We also demonstrate alternative initiator codon usage in both the human and mouse GATA-6 genes. Both isoforms of the protein are synthesized in vitro regardless of which 5' noncoding exon is present in the RNA, although the larger protein has greater transcriptional activation potential in transfection assays. Thus, GATA-6 function in the cell is controlled by a complex interplay of transcriptional and translational regulation.

Investigating persistent hyperferritinaemia without apparent iron overload is challenging. Even when inflammation, cirrhosis, Still's disease, fatty liver and malignancy are excluded, there remains a group of patients with unexplained hyperferritinaemia for whom rare forms of haemochromatosis (ferroportin disease) are a consideration. Preliminary results suggest that abnormal percentage glycosylation of serum ferritin is seen in some cases of genetically determined hyperferritinaemia. Serum ferritin is normally 50–81% glycosylated, but low glycosylation (20–42%) prevails in hereditary hyperferritinaemia cataract syndrome. This contrasts with hyperglycosylation (>90%) associated with the benign hyperferritinaemia related to missense L ferritin (p.Thr30Ile) mutation. Here, we describe two novel missense L ferritin variants also associated with hyperglycosylation, p.Gln26Ile and p.Ala27Val. Ferritin glycosylation, a comparatively simple measurement, can identify patients for DNA sequencing as hyperglycosylation (>90%) is associated with benign hyperferritinaemia and mutant L ferritin chain.

Cirrhotic patients (CPs) are susceptible to spontaneous bacterial peritonitis (SBP). Aim of this study was to examine if this susceptibility was related to peritoneal macrophages' (PMs) altered host defence. Absorbance of phagocytosed particles by PMs from CPs was lower than that of control (31.88% vs. 77.2%). Particle opsonisation increased the absorbance to 41% in CPs' PMs, and this value remains lower than the control; 77.2%. Respiratory burst (RB) was expressed as fluorescence index values, and these were higher in PMs from CPs than in controls (82 vs. 41, 73 vs. 26 and 71 vs. 26). IFN-γ made no further increase of RB values in PMs from CPs. CD14 expression was also higher in CPs' PMs. IFN-γ significantly downregulated CD14 expression in both CPs' PMs and control. Reduced phagocytosis by predominantly CD14-positive PMs from CPs could be related to intense RB. Findings suggest altered host defence that could contribute to susceptibility to SBP.

Summary Hereditary hemochromatosis (HH) is a genetic disorder of iron metabolism. It is an uncommon indication for liver transplantation (LT). It has been suggested that patients who undergo LT for cirrhosis related to HH have higher morbidity and mortality from cardiac, infectious and malignant complications. The purpose of this retrospective review was to determine whether these observations hold true in the current era. We analysed the data of 22 patients who had LT for HH from 1996 to 2007 at our center. Thirteen patients had LT for complications of end-stage liver disease, seven for hepatocellular carcinoma (HCC) and two for subacute liver failure. Cofactors promoting liver disease were identified in 15 patients. Ten patients had iron reduction with venesection before transplantation. Patient and graft survival at 1 and 5 years were 80.7%, and 74% respectively. There were seven deaths after a median follow up of 46 months either because of multiorgan failure, or caused by HCC recurrence. Bacterial infections were the commonest cause of morbidity. Patients with HH remain at a higher risk of developing HCC. Infectious complications are common. Iron reduction with preoperative venesection reduces the risk of cardiac and infection complications postoperatively. Improved survival post-LT reflects changes in selection, disease modification through venesection, and improvement in immunosuppression.

Hepcidin is known to be a key systemic iron-regulatory hormone which has been demonstrated to be associated with a number of iron disorders. Hepcidin concentrations are increased in inflammation and suppressed in hemochromatosis. In view of the role of hepcidin in disease, its potential as a diagnostic tool in a clinical setting is evident. This study describes the development of a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) assay for the quantitative determination of hepcidin concentrations in clinical samples. A stable isotope labeled hepcidin was prepared as an internal standard and a standard quantity was added to urine samples. Extraction was performed with weak cation-exchange magnetic nanoparticles. The basic peptides were eluted from the magnetic nanoparticles using a matrix solution directly onto a target plate and analyzed by MALDI-TOF MS to determine the concentration of hepcidin. The assay was validated in charcoal stripped urine, and good recovery (70–80%) was obtained, as were limit of quantitation data (5 nmol/L), accuracy (RE

Hepcidin is a peptide hormone that functions as a key regulator of mammalian iron metabolism. Serum and urine levels are increased in inflammation and suppressed in hemochromatosis, and they may have diagnostic importance. This study describes the development and validation of an analytical method for the quantitative determination of the concentration of hepcidin in clinical samples. A stable, isotopically labeled internal standard, [15N,13C2]Gly12,20-hepcidin, was synthesized and a standard quantity was added to urine samples. Extraction was performed using weak cation exchange magnetic nanoparticles. An ion trap mass spectrometer was used to quantify hepcidin in the samples. The hepcidin assay was validated, and good recovery of hepcidin was obtained. The assay is accurate and precise. Urinary hepcidin levels of 3 to 9 nmol/mmol creatinine(-1) were found in healthy controls, with reduced levels in hemochromatosis (P

Measurement of serum iron increase after ingestion of a meal could be an efficient method of comparing post-prandial iron absorption between groups of individuals. We determined whether the rise in post-prandial serum iron is increased in fully treated patients with hereditary haemochromatosis (HFE C282Y+/+; HH) compared to iron deficiency anaemia (IDA), iron-replete heterozygous subjects (HFE C282Y+/-) and iron-replete controls (HFE C282Y-/-).Serum iron increase was measured over 4h after a meal containing 13.1 mg non-haem iron.Post-prandial increase in serum iron was similar in treated HH versus IDA (P=0.54), but greater than control subjects (P0.0001). In five HH patients, using (58)Fe as a tracer, the rate of iron absorption was increased (P0.05) and serum non-transferrin bound iron showed a tendency to increase (P=0.06). Serum iron curves did not differ for heterozygous subjects and controls (P=0.65).Using the serum iron method we found a comparable increase in post-prandial iron absorption in treated HH and IDA compared with controls. While post-prandial iron absorption in the group heterozygous for the C282Y mutation was modestly increased relative to controls, this difference was not statistically significant.

During the long-term treatment of patients with hereditary haemochromatosis (HH) the authors observed that proton pump inhibitors (PPI) reduced the requirement for maintenance phlebotomy. Gastric acid plays a crucial role in non-haem iron absorption and the authors performed a case review and intervention study to investigate if PPI-induced suppression of gastric acid would reduce dietary iron absorption in C282Y homozygous patients.Phlebotomy requirements to keep serum ferritin approximately 50 microg/l before (mean 6.1 (SE 0.6) years) and during (3.8 (0.9) years) administration of a PPI were evaluated in seven patients and a post-prandial study was performed to determine whether PPIs reduce absorption of non-haem iron (14.5 mg) from a test meal in a further 14 phlebotomised patients with normal iron stores.There was a significant reduction (p0.001) in the volume of blood removed annually before (2.5 (0.25) l) and while taking (0.5 (0.25) l) a PPI. Administration of a PPI for 7d suppressed absorption of non-haem iron from the meal as shown by a significant reduction (all p0.01) in: area under the serum curve (2145 (374) versus 1059 (219)), % recovery of administered iron at peak serum iron (20.5 (3.2) versus 11.0 (2.0)%) and peak serum iron (13.6 (2.4) vs 6.1 (1.2) micromol/l) (all values are before vs during PPI).Administration of a PPI to patients with HH can inhibit the absorption of non-haem iron from a test meal and the habitual diet.

Haemochromatosis (HH) is a clinically and genetically heterogeneous disease caused by inappropriate iron absorption. Most HH patients are homozygous for the C282Y mutation in the HFE gene. However, penetrance of the C282Y mutation is incomplete, and other genetic factors may well affect the HH phenotype. Ferroportin and TFR2 mutations also cause HH, and two HAMP mutations have recently been reported that causes juvenile haemochromatosis (JH) in the homozygous state. Here, we report evidence for digenic inheritance of HH. We have detected two new HAMP mutations in two different families, in which there is concordance between severity of iron overload and heterozygosity for HAMP mutations when present with the HFE C282Y mutation. In family A, the proband has a JH phenotype and is heterozygous for C282Y and a novel HAMP mutation Met50del IVS2+1(-G). This is a four nucleotide ATGG deletion which causes a frameshift. The proband's unaffected mother is also heterozygous for Met50del IVS2+1(-G), but lacks the C282Y mutation and is heterozygous for the HFE H63D mutation. Met50del IVS2+1(-G) was absent from 642 control chromosomes. In family B, a second novel, less severe HAMP mutation, G71D, was identified. This was detected in the general population at an allele frequency of 0.3%. We propose that the phenotype of C282Y heterozygotes and homozygotes may be modified by heterozygosity for mutations which disrupt the function of hepcidin in iron homeostasis, with the severity of iron overload corresponding to the severity of the HAMP mutation.

After identification of the hereditary haemochromatosis gene HFE, and receipt of confirmation that most patients with the condition were homozygous for a single, founder mutation (C282Y), most assumed that C282Y would be a prevalent, highly penetrant mutation in a gene that plays a key part in the regulation of iron absorption and of whole-body iron homoeostasis. With carrier rates of between 10% and 15%, and a homozygote frequency of about one-in-150 in people of northern European descent, C282Y is certainly prevalent. However, it is not highly penetrant. The pronounced variation in phenotype in individuals with the same gene mutation has prompted the search for modifier genes at other loci, and for environmental factors that might affect expression of the condition. Progress in our understanding of how HFE regulates the absorption of dietary iron has been slow, but much can be learnt from the study of the rare instances of haemochromatosis that involve mutations in newly-identified iron-metabolism genes, such as TFR2--a transferrin receptor isoform--and ferroportin1/Ireg1/mtp1--an intestinal iron transporter. The availability of definitive information on penetrance and the identity of genetic modifiers will aid the debate on whether population screening for haemochromatosis should be undertaken or whether alternative strategies should be implemented to improve early detection.

Iron is an essential element playing a vital role in many cellular processes. This requirement is complicated by the fact that environmental iron is invariably present as insoluble Fe 3+ leading to poor bioavailability and toxicity, since even low concentrations of iron catalyse the production of damaging reactive oxygen species. As a result organisms have evolved efficient uptake and transport systems to extract iron from their environment as well as ferritins that store iron in a non-toxic form. In higher organisms, the first membrane barrier encountered is the apical surface of the duodenal enterocyte, a specialized absorptive cell of the intestinal epithelium that undertakes vectorial transport of iron. Iron is initially solubilized by reduction and Fe 2+ is transported across the cell membrane by a carrier-mediated transport process. This is followed by intracellular transfer of iron to the basolateral enterocyte membrane with subsequent transfer and release of iron to transferrin in the portal blood. A second site of iron transport is at the placento–fetal barrier where similar principles operate. In this review we describe recently identified transmembrane transporters and associated accessory proteins responsible for iron transport at these two sites.

Aims/background alpha1-antitrypsin (alpha1-AT) is a hepatic acute phase protein which predominantly inhibits neutrophil elastase. Besides this major function, we have also previously shown that alpha1-AT markedly increased H-ferritin mRNA expression and ferritin synthesis in the human hepatoma cell line HepG 2. These actions suggest that alpha1-AT might interact with HepG 2 cells via a specific cell surface binding site. Methods and results Using radio-labelled native alpha1-AT, we observed saturable binding to HepG 2 cells with a dissociation constant (Kd) of 63.3+/-6.9 nM and a maximal density of binding sites (Bmax) of 0.34+/-0.05 pmol/10(6) cells equivalent to 195,800+/-29,200 sites/cell. The binding of [125I]alpha1-AT was time dependent with a calculated association rate constant of 9.22+/-1.84x10(4)xM(-1)xmin(-1). Binding was highly specific since other acute phase proteins or protease inhibitors failed to block binding. Although alpha1-AT-trypsin, alpha1-AT-elastase and the pentapeptide FVYLI, the minimal binding sequence for the SEC receptor, increased [125I]alpha1-AT binding, in long term experiments these complexes failed to influence the number of alpha1-AT binding sites. Specific, saturable binding of [125I]alpha1-AT was also found on the human intestinal epithelial Caco 2 cells, but not on fibroblast or leukaemic cell lines. Conclusion These experiments demonstrate a specific, high affinity binding site for native alpha1-AT on HepG 2 and Caco 2 cells, cell lines derived from tissues involved in the acute phase response.

The effect of transforming growth factor beta 1 (TGF-beta1) on levels of hepatocyte growth factor/scatter factor (HGF/SF) gene transcripts was investigated in the human lung embryonic fibroblast cell line, MRC-5. TGF-beta1 markedly reduced the expression of the 6. 0-kb and 3.0-kb HGF/SF mRNA, which encode full-length HGF/SF, but it had little effect on the expression of the alternatively spliced 1. 5-kb mRNA, which encodes NK2, a competitive HGF/SF antagonist. Using actinomycin D to block RNA synthesis, it was observed that TGF-beta1 had little effect on the stability of the 1.5-kb NK2 mRNA but increased the rate of degradation of the 6.0- and 3.0-kb HGF/SF mRNA transcripts by a mechanism that was dependent on new protein synthesis. TGF-beta1 minimally increased rather than reduced HGF/SF promoter activity in cells transiently transfected with chloramphenicol acetyltransferase (CAT) reporter genes driven by HGF/SF gene 5'-flanking sequences. In MRC-5 cells, TGF-beta1 modulates HGF/SF gene transcripts at the posttranscriptional level in order to favour expression of the 1.5-kb mRNA that encodes the truncated protein NK2.

Iron absorption by the duodenal mucosa is initiated by uptake of ferrous Fe(II) iron across the brush border membrane and culminates in transfer of the metal across the basolateral membrane to the portal vein circulation by an unknown mechanism. We describe here the isolation and characterization of a novel cDNA (Ireg1) encoding a duodenal protein that is localized to the basolateral membrane of polarized epithelial cells. Ireg1 mRNA and protein expression are increased under conditions of increased iron absorption, and the 5' UTR of the Ireg1 mRNA contains a functional iron-responsive element (IRE). IREG1 stimulates iron efflux following expression in Xenopus oocytes. We conclude that IREG1 represents the long-sought duodenal iron export protein and is upregulated in the iron overload disease, hereditary hemochromatosis.

Hepatocyte growth factor plays a key role in liver regeneration but the role of liver in its synthesis in acute liver failure is unclear. We therefore measured hepatic expression of hepatocyte growth factor mRNA in this condition in comparison to H3 histone mRNA, a marker of cellular proliferation. Hepatocyte growth factor mRNA levels were quantified by specific RNase protection assay in nine patients with acute liver failure and found to be similar to those in six normal controls. Hepatocyte proliferation, as assessed by H3 histone mRNA expression, was not detected in normal liver but was present in six of nine patients with acute liver failure (P < 0.05) and was not correlated with expression of hepatocyte growth factor mRNA (rs= −0.28). Liver is unlikely to be the source of the high serum hepatocyte growth factor levels observed in acute liver failure.

Sickle cell disease (SCD) has evolved into a debilitating disorder with emerging end-organ damage. One of the organs affected is the liver, causing “sickle hepatopathy,” an umbrella term for a variety of acute and chronic pathologies. Prevalence of liver dysfunction in SCD is unknown, with estimates of 10%. Dominant etiologies include gallstones, hepatic sequestration, viral hepatitis, and sickle cell intrahepatic cholestasis (SCIC). In addition, causes of liver disease outside SCD must be identified and managed. SCIC is an uncommon, severe subtype, with outcome of its acute form having vastly improved with exchange blood transfusion (EBT). In its chronic form, there is limited evidence for EBT programs as a therapeutic option. Liver transplantation may have a role in a subset of patients with minimal SCD-related other organ damage. In the transplantation setting, EBT is important to maintain a low hemoglobin S fraction peri- and posttransplantation. Liver dysfunction in SCD is likely to escalate as life span increases and patients incur incremental transfusional iron overload. Future work must concentrate on not only investigating the underlying pathogenesis, but also identifying in whom and when to intervene with the 2 treatment modalities available: EBT and liver transplantation.

Simon et al 1 in 1976 first reported the association between the leucocyte antigens HLA-A3 and HLA-B14 and genetic haemochromatosis (GH). Now, 20 years later, Feder et al 2 report the cloning of what is the strongest candidate gene for this disorder to have been identified so far. Formal proof from functional studies is now required to confirm that mutations in this gene are responsible for causing haemochromatosis. The question now arises as to why this gene has proved so elusive.

Xenopus GATA-6 transcripts are first detected at the beginning of gastrulation in the mesoderm, and subsequent domains of expression include the field of cells shown to have heart-forming potential. In this region, GATA-6 expression continues only in those cells that go on to form the heart; however, a decrease occurs prior to terminal differentiation. Artificial elevation of GATA-6, but not GATA-1, prevents expression of both cardiac actin and heart-specific myosin light chain. This effect is heart-specific because cardiac actin expression is unaffected in somites. Expression of the earlier marker XNkx-2.5 was unaffected and morphological development of the heart was initiated independently of the establishment of the contractile machinery. We conclude that a reduction in the level of GATA-6 is important for the progression of the cardiomyogenic differentiation programme and that GATA-6 may act to maintain heart cells in the precursor state. At later stages, when the elevated GATA-6 levels had decayed, differentiation ensued but the number of cells contributing to the myocardium had increased, suggesting either that the blocked cells had proliferated or that additional cells had been recruited.

A selective pathway for the degradation of specific long-lived cytosolic proteins is activated in response to starvation in vivo or to serum withdrawal from cultured cells. It involves recognition of a targeting motif by a member of the hsp70 family. A 5-residue targeting motif has been proposed on the basis of sequence comparisons. We investigate whether there is any structural basis for this motif being the true recognition signal. We examine the conformations of four motif peptides in proteins that are either known to be serum regulated or are from related vertebrate species, and two equivalent peptides in bacterial proteins that closely resemble other regulated proteins. Our studies show that all the motif sequences are located near the ends of surface helices with one or more of the residues buried in the structure, yet it is known that members of the hsp70 family tend to interact with extended peptide chains. Furthermore, recognition by these proteins generally requires a specific ordering of key residues, yet the motif implies a largely order-independent sequence characterized by residue type only. We conclude that the proposed motif is unlikely to be the true targeting signal for lysosomal degradation unless additional factors apply.

Cytosolic aconitase activity was assayed in duodenal mucosa from mice subjected to a variety of manipulations known to modulate duodenal iron status and duodenal iron absorption. No changes in cytosolic aconitase activity were observed 1 h after oral FeSO4 dosing or intramuscular desferrioxamine treatment. Three days of hypoxic exposure and two weeks treatment with intramuscular iron dextran also had no effect on cytosolic aconitase. Three weeks growth on an iron deficient diet significantly reduced cytosolic aconitase activity. In no situation was there any evidence for significant amounts of inactive aconitase which could be activated in vitro with FeSO4/cysteine. These data suggest that duodenal cytosolic aconitase is not sensitive to acute changes in mucosal iron levels and its generally much less sensitive to body iron status than is duodenal iron absorption. There is evidence that chronic iron depletion reduces cytosolic aconitase to a relatively small degree but generally activity is maintained, consistent with an important metabolic role for the enzyme.

The haemochromatosis gene (HFE) is linked to both HLA-A and D6S105 on the short arm of chromosome 6 but these markers are separated by approximately 2 Mb of DNA. Most chromosomes carrying HFE have a common haplotype which extends from HLA-A to D6S105 and includes HLA-F. To localise the gene more precisely we have examined 10 microsatellite markers extending over a genetic distance of approximately 5 cM from D6S265 (within 100 kb of HLA-A on the centromeric side) to D6S299 (telomeric). The order of markers is D6S265, HLA-F, D6S258, D6S306, CS3, D6S105, D6S464, CS5, D6S461 and D6S299. We confirm that haemochromatosis appears to originate from a founder mutation which has multiplied in the population through successive generations. This mutation is associated with the haplotype D6S306-5, CS3-3, D6S105-8, D6S464-9 and CS5-4 which is found on approximately 70% of HFE chromosomes. We have applied a new and powerful, likelihood analysis for linkage disequilibrium. The maximum value of lambda (proportion of total possible association between a marker and disease) is 0.74 for marker CS5 (allele 4). A multipoint analysis also gives a maximum likelihood near marker CS5. We conclude that the HFE gene is likely to be located telomeric of D6S105 and close to CS5.

We propose that the frequency and severity of multi-organ failure (MOF) in fulminant hepatic failure (FHF) involves free radical damage caused by the presence of circulating iron and copper ions, catalytic for free radical reactions. The presence of such metal ions is demonstrated by using the sensitive bleomycin and phenanthroline assays. Antioxidant therapy, e.g., using chelating agents that prevent metal ions from stimulating free radical reactions, may have benefit in the treatment of FHF and its consequences.

Cellular iron homoeostasis is maintained by iron sensor proteins known as iron-regulatory proteins (IRPs), which act post-transcriptionally by binding RNA stem-loop structures, termed iron-responsive elements (IREs), present on the mRNAs of proteins involved in iron storage, utilization and transport. IRP1 is a bifunctional protein that can act either as a cytoplasmic aconitase or as an IRE-binding protein. The RNA-binding activity of IRP1 is regulated post-translationally by the insertion or extrusion of a 4Fe-4S cluster, without changes in the levels of protein. In hereditary haemochromatosis (HH) accumulation of iron in parenchymal tissues, including the liver, occurs, possibly through dysfunctional IRP1. Investigation of IRP1 expression in liver biopsies from HH patients showed that the protein is completely absent or markedly reduced in heavily iron-loaded HH patients. Real-time PCR was then conducted in an attempt to investigate the mRNA levels and establish the underlying mechanism behind the disappearing act of IRP1. The two possibilities are: transcriptional regulation (through the inhibition of transcription) or post-transcriptional regulation (either through increased turnover of protein or inhibition of translation) of IRP1. Preliminary data suggest that transcription of IRP1 is not affected by chronic iron overload, and down-regulation may be attributable instead to degradation of the protein.

Summary OBJECTIVE Recent reports have suggested that hypogonadotrophic hypogonadism in men with genetic haemochromatosis can be reversed by aggressive venesection therapy. We have studied prospectively men with this complication of haemochromatosis in order to document the frequency and completeness of recovery from hypogonadism. PATIENTS AND DESIGN Six men with symptomatic hypogonadotrophic hypogonadism and genetic haemochromatosis were studied before beginning venesection therapy and again after depletion of body iron stores. MEASUREMENT Symptoms of hypogonadism, serum gonadotrophins and serum total and free testosterone concentrations. RESULTS Five men aged 47–66 showed no symptomatic improvement and no change in serum gonadotrophin or testosterone concentrations. The symptoms of one man, aged 33, resolved completely after venesection and this was accompanied by increases in serum LH and FSH. Serum total and free testosterone concentrations increased fourfold, but remained subnormal. CONCLUSION Only one partial recovery from hypogonadotrophic hypogonadism was seen and this was in the youngest subject. In reviewing the other documented cases of reversal it would appear that the age at diagnosis is critical and there are no proven cases of reversal of hypogonadotrophic hypogonadism in men over the age of 40 at the start of venesection therapy.

Milk thistle contains silybin, which is a potential iron chelator. We aimed to determine whether silybin reduced iron absorption in patients with hereditary haemochromatosis. In this crossover study, on three separate occasions, 10 patients who were homozygous for the C282Y mutation in the HFE gene (and fully treated) consumed a vegetarian meal containing 13.9 mg iron with: 200 ml water; 200 ml water and 140 mg silybin (Legalon Forte); or 200 ml tea. Blood was drawn once before, then 0.5, 1, 2, 3 and 4 h after the meal. Consumption of silybin with a meal resulted in a reduction in the postprandial increase in serum iron (AUC±s.e.) compared with water (silybin 1726.6±346.8 versus water 2988.8±167; P

Hepcidin is a peptide hormone that functions as a key regulator of mammalian iron metabolism. Biological levels are increased in end-stage renal disease and during inflammation but suppressed in hemochromatosis. Thus hepcidin levels have diagnostic importance. This study describes the development of an analytical method for the quantitative determination of the concentration of hepcidin in clinical samples. The fragmentation of hepcidin was investigated using triple quadrupole and linear ion trap mass spectrometers. A standard quantity of a stable isotopically labelled hepcidin internal standard was added to serum samples. Extraction was performed by protein precipitation and weak cation-exchange magnetic nanoparticles. Chromatography was carried out on sub 2 microm particle stationary phase, using ultra-high-pressure liquid chromatography and a linear ion trap for quantitation. The lower limit of quantitation was 0.4 nmol/L with less than 20% accuracy and precision. The mean hepcidin concentration in sera for controls was 4.6 +/- 2.7 nmol/L, in patients with sickle cell disease, 7.0 +/- 8.9 nmol/L; in patients with end-stage renal disease, 30.5 +/- 15.7 nmol/L; and patients with penetrant hereditary hemochromatosis, 1.4 +/- 0.8 nmol/L.

Interferon-α elicits antiviral and immunoregulatory activities by binding to specific receptors on the cell surface. In this study, binding characteristics of interferon-α to peripheral blood mononuclear cells in patients with chronic hepatitis B virus infection were studied using radioiodinated recombinant interferon-α2b to determine interferon-α receptor numbers and dissociation constants. A single class of interferon-α receptor was demonstrated on peripheral blood mononuclear cells and mononuclear subsets. Peripheral blood mononuclear cells from patients with chronic hepatitis B virus infection (n = 20) and controls (n = 16) expressed a similar number of interferon-α receptors (484 ± 175 vs. 511 ± 168 sites/cell respectively, p = NS) with a similar dissociation constant (dissociation constant ± 0.2 to 0.7 nmol/L). Expression of interferon-α receptors was similar in monocyteenriched and lymphocyte-enriched fractions in both groups. Similar changes were observed in patients receiving α-interferon therapy. There was no correlation between interferon-α receptors expression and serum transaminase, serum HBsAg, serum HBV DNA, liver histological findings or the response to interferon-α therapy. After incubation of lymphocytes in vitro with interferon-α2b (10 to 1,000 U/ml), interferon-α receptors number dropped by 42% to 80%, but this was associated with an increase in binding affinity (dissociation constant ≈ 0.05 to 0.15 nmol/L) in both patients and controls. There was significant delay in the initial phase of receptor recovery in the patients with chronic hepatitis B virus infection compared with normal controls (days 1 and 2, p

Hepatocellular carcinoma (HCC) has traditionally been considered a rare complication of cirrhosis secondary to autoimmune hepatitis (AIH), yet the true incidence remains unknown due to a lack of published data. Consequently, some professional guidelines do not mandate routine surveillance for HCC in this condition. Our aims were to evaluate the rate at which HCC develops among a large, prospectively obtained cohort of patients with AIH at a single center. Demographic, clinical, and laboratory indices associated with the development of HCC were also identified. HCC was discovered in 15 of 243 patients with AIH, all of whom had type 1 AIH equating to 1090 cases per 100,000 patient follow-up years. HCC occurred in the same proportion of females as males, 6.1% versus 6.4%, P = 0.95. HCC occurred more frequently in patients who had cirrhosis at presentation, 9.3% versus 3.4%, P = 0.048, or who had a variceal bleed as the index presentation of AIH, 20% versus 5.3%, P = 0.003. The median duration from time of confirmed cirrhosis to a diagnosis of HCC was 102.5 months, range 12-195 months. Median survival in patients whose HCC was diagnosed on surveillance was 19 months (range 6-36 months) compared with 2 months (range 0-14 months) for patients presenting symptomatically (P = 0.042). Conclusion: Cirrhosis in AIH is the sine qua non for HCC development, which subsequently occurs at a rate of 1.1% per year and affects men and women in equal proportions. (HEPATOLOGY 2008.)

In genetic hemochromatosis, metabolic studies have demonstrated inappropriately increased iron absorption by cells of the duodenal mucosa. It is not clear whether this reflects an intrinsic abnormality of iron homeostasis at this site or is a consequence of a more generalized defect in cellular iron metabolism particularly involving the liver. We have previously used the expression of iron-related proteins as markers of iron homeostasis and have demonstrated normal regulation of the transferrin receptor and ferritin in the liver in this condition. In the present study we used immunohistochemical techniques to study transferrin-receptor expression in the gastrointestinal epithelium in normal subjects and patients with iron overload. In untreated genetic hemochromatosis and normal subjects, villus epithelial cells expressed receptor in the basolateral, subnuclear region. In contrast, in patients with secondary iron overload, receptor staining was absent in villus epithelial cells. The cells in the duodenal crypts showed intense staining for the transferrin receptor in all subjects investigated, a finding consistent with the known behavior of this receptor in proliferating cells. Given that body iron stores in both types of iron overload were comparable, these findings indicating a failure of down-regulation of the villus enterocyte transferrin receptor in genetic hemochromatosis may reflect the presence of a regulatory defect associated with the inability to control iron absorption in this condition.

Background & Aims: Hepatic dysfunction in adults with sickle cell disease varies in character and severity from self-limited cholestasis to life-threatening acute liver failure and cirrhosis. Because previous attempts to describe patterns of liver disease have not reflected clinical experience, we aimed to characterize the presentation, clinicopathologic findings, and natural history of such patients. Methods: We reviewed the clinical, laboratory, radiographic, and histologic features with the natural history of 38 patients (mean age, 33 years) with Hb SS, SC, or S-β thalassemia referred to a tertiary liver center for assessment. Results: Distinct disease patterns were identified that comprised massive hepatocellular necrosis (5%), acute severe sequestration and cholestasis in the context of sepsis (18%), cirrhosis (18%), chronic, fluctuating sequestration without cholestasis (21%), mechanical biliary obstruction (8%), siderosis without cirrhosis (8%), generalized cholangiopathy (8%), venous outflow obstruction (3%), and miscellaneous (11%). Of the 20 who required emergency admission, 8 did not survive their index admission, and 3 patients died during follow-up admissions (4 months–4 years later). There were 3 instances of hemorrhage related to liver biopsy. One patient underwent transplantation but died. Hematologic and biochemical markers did not discriminate well between survivors and nonsurvivors. The incidence of a second hepatic pathology (ie, viral hepatitis, autoimmune disease, transfusional siderosis) was 37% and was associated with the finding of more advanced histologic fibrosis. Conclusions: Patterns of hepatic dysfunction in sickle cell disease are diverse and demand clear characterization for each individual; however, groups with a poor prognosis can be identified after collation of clinical, laboratory, and radiologic data. Findings at biopsy (which is associated with higher risk of bleeding in this group) might be anticipated by noninvasive test results.

Complications affecting multiple organs, including the liver, contribute to early mortality in patients with sickle cell disease (SCD). Earlier diagnosis and monitoring of "sickle hepatopathy", preferably using non-invasive methods, would enable earlier intervention and therefore, potentially a better outcome for patients. In many non-SCD chronic liver diseases, fibrosis stage is the most important predictor of morbidity and mortality. Two non-invasive methods of assessing liver fibrosis are used: Transient Elastography (TE, Echosens) and Enhanced Liver Fibrosis Score™ (ELF, iQUR). TE detects fibrosis using ultrasound and low frequency elastic waves with a propagation velocity directly related to the stiffness of the liver. The ELF score examines the balance between matrix deposition and degradation using levels of three proteins analysed using a patented formula. We report a prospective study correlating liver function tests (LFTs) with the level of liver fibrosis (as ascertained by TE and ELF) in a cohort of patients with SCD. Ethical approval for this study was obtained from the NHS ethics committee (11/LO/0005) and patients were consecutively recruited in the steady-state sickle cell clinic at Kings' College Hospital, London, during 2012. Patients were excluded if they had viral hepatitis or were pregnant. Clinical (transfusion and hydroxyurea therapy), imaging (liver iron concentration, LIC) and laboratory data were collected during steady-state. TE and ELF were performed on 194 patients. The patients ranged from 17-72 years (mean age 35 years); 78 (40%) were male, 134 (68%) had HbSS or HbSb0 (SCA), 48 (26%) Hb SC, and the remainder, Hb Sβ+ (excluded due to low numbers). Statistical analysis was undertaken in IBM SPSS version 20. There was significant correlation between both TE and ELF with age, when corrected for sickle genotype (TE β = 0.19, p = 0.006 and ELF β = 0.2, p = 0.005) (Figure). Patients with SCA had significantly higher TE results and mean ELF scores than those with HbSC (TE, 6.8 vs 5.3, p In SCA patients, TE correlated significantly with all serum LFTs (Albumin R = -0.35 p In SCA patients, ELF score correlated with serum LFTs (Albumin R = -0.30 p These data show significant levels of liver dysfunction in our SCD population using both TE and ELF score which correlated significantly with abnormal LFTs and markers of hemolysis and iron overload. The role of TE and ELF in monitoring liver dysfunction in SCD needs to be further validated, preferably with longitudinal, and if possible histological data. Table 1. Range and mean TE results and ELF score for whole cohort and subgroups. Whole cohort n = 194 (%) SCA n = 134 (%) Hb SC n = 48 (%) p value FibroScan results (kPa) Mean (range) 6.3 (2.0 - 21.3) 6.8 (2.0 - 21.3) 5.3 (2.0 - 16.0) < 0.0001 None/mild (0-7.65) 153 (79) 98 (73) 43 (90) Moderate (7.66-13.00) 33 (17) 29 (22) 4 (8) Severe (≥13.01) 8 (4) 7 (5) 1 (2) ELF score Mean (range) 9.1 (7.1 - 11.6) 9.2 (7.1 - 11.6) 8.6 (7.5 - 10.3) Disclosures No relevant conflicts of interest to declare.

Introduction Hepatocellular carcinoma (HCC) rates are higher in patients with hereditary haemochromatosis (HH) compared to other aetiologies. Survival with or without liver transplantation (LT) is often deemed less favourable. Modern mortality rates post LT or following loco-regional therapy (LRT) are not well reported therefore prognostic pessimism may be misplaced. Method Consecutive patients with HH and HCC diagnosed between 2000 and 2013 at our institution were studied. Patients were offered curative liver transplantation (LT), radiofrequency ablation (RFA) or surgical resection; or, non-curative treatment with trans-arterial chemo-embolization (TACE), sorafenib or symptom control according to performance status and Barcelona Clinic Liver Cancer (BCLC) stage. Patient characteristics recorded at time of first HCC diagnosis included demographics, tumour size and multiplicity, severity of liver disease, serum ferritin (SF, as a proxy for HH treatment) and alphafetoprotein (AFP). The primary end-point was all-cause mortality. Results Forty-one patients (median (range) age 67(44–78) years, 97% male, MELD 8(5–31)) made up the study cohort with a median follow up of 22(3–126) months. Thirty-six patients had cirrhosis and median SF was 256(27–5718) mg/L and median AFP 29(2–197926) kIU/L. Twenty-seven (66%) patients had solitary tumours, 44% were BCLC stage A, 27% BCLC-B, 10% BCLC-C and 5% BCLC-D. TACE was the commonest LRT choice in 21 (49%) patients. Four patients (9%) underwent surgical resection and RFA was performed in 5 (12%) patients. Fourteen patients (32%) underwent LT. Median survival was 27 (95% CI 17–41) months. Patients with >1 HCC did not have decreased survival compared to those with a single tumour (p = 0.386). Five-year survival for patients receiving curative therapy was 77% (80% for LT, 67% for surgery/RFA), and for those undergoing non-curative therapy 5-year survival was 15% (23% for patients receiving TACE). For BCLC-A patients 5-year survival was 64%, 50% for BCLC-B patients and 9% for BCLC-C/D patients (p = 0.002). On age-adjusted Cox regression survival analysis BCLC-C/D stage was independently associated with poor survival (Hazard Ratio 4.05 (1.29–12.63), p = 0.016) but not serum AFP, SF or the presence of cirrhosis. Conclusion Patients with HCC in the context of HH can achieve comparable survival rates following curative modalities to those with other aetiologies. The BCLC staging system accurately stratifies survival and excellent 5-year survival is possible following LT in selected patients. Disclosure of interest None Declared.

Severe alcoholic hepatitis is associated with high morbidity and short-term mortality. Corticosteroids are the only widely used therapy but established contraindications to treatment or the risk of serious side-effects limit their use. The perceived need for alternative treatments together with the theoretical benefits of anti-oxidant therapy triggered the design of a randomised clinical trial comparing these treatment modalities.One hundred and one patients were randomized into a clinical trial of corticosteroids or a novel antioxidant cocktail with a primary endpoint of 30-day mortality.At 30 days there were 16 deaths (30%) in the corticosteroid treated group compared with 22 deaths (46%) in the antioxidant treated group (P=0.05). The odds of dying by 30 days were 2.4 greater for patients on antioxidants (95% confidence interval 1.0-5.6). A diagnosis of sepsis was made more frequently in the AO group (P=0.05), although microbiologically proven episodes of infection occurred more often in the CS group (P0.01). The survival advantage for corticosteroid treated patients was lost at 1 year of follow-up (P=0.43).This study has shown that corticosteroids in the form of prednisolone 30 mg daily are superior to a broad antioxidant cocktail in the treatment of severe alcoholic hepatitis.

Many clinical studies have indicated that diets rich in fish oil (FO) reduce the risk of cardiovascular disease and have anti-inflammatory and antithrombotic properties. Although the therapeutic effects of FO have been well described, their impact on iron metabolism remains unclear. The aim of this work was to study the activity and expression of IRP1 in the liver and the spleen of rats fed FO-rich diets with 0 (FO-0) or 100 (FO-1) mg/kg of all-rac-alpha-tocopherol acetate. We also measured nonheme iron, alpha-tocopherol and retinol concentrations, and superoxide (SOD) and catalase activity in these organs. Rats fed FO were compared to rats fed a corn oil (CO)-rich diet with 100 mg/kg all-rac-alpha-tocopherol acetate. The activity and expression of IRP1 in both the liver and the spleen of rats fed FO diets were greater than in those fed the CO diet. FO-fed rats also had lower nonheme iron concentrations in these organs. Hepatic alpha-tocopherol and retinol concentrations and SOD activity were lower in FO-0-fed rats compared to those fed the CO diet. In the spleen, alpha-tocopherol and retinal concentrations were not altered but SOD activity was lower in FO-0- fed rats, whereas catalase activity was greater than in rats fed CO. The results indicate that there is an increase in oxidative stress in the liver and in the spleen of rats fed FO diets. These changes, together with the reduction of nonheme iron concentrations in both FO-0- and FO-1-fed rats, may explain the increase in activity and expression of IRP1. Therefore, the ingestion of FO-rich diets should be monitored under close supervision.

Haemochromatosis is a common inherited disease of iron metabolism which leads to toxic accumulation of iron in parenchymal tissues. Most patients have mutations in the HFE gene on chromosome 6p. In these classical HFE-related cases, liver biopsy shows iron accumulation primarily in hepatocytes, with Kupffer cell deposition occurring later when hepatocytes are heavily loaded. Rarer non HFE-related haemochromatosis accounts for approximately 5% of patients with haemochromatosis in the UK; in other countries such as Italy, this percentage is higher...

Iron is an essential element playing a vital role in many cellular processes. This requirement is complicated by the fact that environmental iron is invariably present as insoluble Fe(3+) leading to poor bioavailability and toxicity, since even low concentrations of iron catalyse the production of damaging reactive oxygen species. As a result organisms have evolved efficient uptake and transport systems to extract iron from their environment as well as ferritins that store iron in a non-toxic form. In higher organisms, the first membrane barrier encountered is the apical surface of the duodenal enterocyte, a specialized absorptive cell of the intestinal epithelium that undertakes vectorial transport of iron. Iron is initially solubilized by reduction and Fe(2+) is transported across the cell membrane by a carrier-mediated transport process. This is followed by intracellular transfer of iron to the basolateral enterocyte membrane with subsequent transfer and release of iron to transferrin in the portal blood. A second site of iron transport is at the placento-fetal barrier where similar principles operate. In this review we describe recently identified transmembrane transporters and associated accessory proteins responsible for iron transport at these two sites.