IL10 promoter haplotypes may contribute to altered cytokine expression and systemic inflammation in celiac disease.

Celiac disease (CD) is an autoimmune/inflammatory condition triggered by dietary gluten intake in genetically predisposed individuals. Though associations with MHC class II HLA-DQ2 or -DQ8 are the primary and necessary genetic predisposition for CD, >97% of genetically predisposed individuals never develop CD. Cytokines were measured in the serum of CD patients and controls. Possible associations with IL10 promoter variants were investigated. Cytokine expression from PBMCs was monitored in response to gluten exposure, or CD3/TCR complex stimulation in the absence or presence of recombinant IL-10. Serum cytokines varied between patients with CD at the time of diagnosis, after dietary elimination of gluten, and healthy controls. Serum IL-17A reflected disease activity. Reduced IL-10 serum levels and altered IL-10 expression by PBMCs coincided with IL10 promoter haplotypes that encode for "low" IL-10 expression (ATA). Increased prevalence of ATA IL10 promoter haplotypes and subsequently reduced IL-10 expression may be an immunological cofactor in individuals genetically predisposed for the development of CD. Resulting cytokine imbalances may be utilized as disease biomarkers in CD.

Antifibrotic therapies in the liver.

Significant progress has been made in understanding the principles underlying the development of liver fibrosis. This includes appreciating its dynamic nature, the importance of active fibrolysis in fibrosis regression, and the plasticity of cell populations endowing them with fibrogenic or fibrolytic properties. This is complemented by an increasing array of therapeutic targets with known roles in the progression or regression of fibrosis. With a key role for fibrosis in determining clinical outcomes and encouraging data from recently Food and Drug Administration-approved antifibrotics for pulmonary fibrosis, the development and validation of antifibrotic therapies has taken center stage in translational hepatology. In addition to summarizing the recent progress in antifibrotic therapies, the authors discuss some of the challenges ahead, such as achieving a better understanding of the interindividual heterogeneity of the fibrotic response, how to match interventions with the ideal patient population, and the development of better noninvasive methods to assess the dynamics of fibrogenesis and fibrolysis. Together, these advances will permit a better targeting and dose titration of individualized therapies. Finally, the authors discuss combination therapy with different antifibrotics as possibly the most potent approach for treating fibrosis in the liver.

Aceruloplasminaemia: a family with a novel mutation and long-term therapy with deferasirox.

Ceruloplasmin is a member of the multicopper oxidase family that plays a major role in the transport of iron in the body. Aceruloplasminaemia (ACP) is a rare disease and is clinically identified by iron overload in liver, pancreas, brain, and other organs, and by microcytic anaemia. So far, the iron chelator deferasirox was given for therapy only up to 6 months due to side effects. Here, we describe a novel mutation leading to ACP and report for the first time a long-term therapy, that is, 2 years with deferasirox. ACP was diagnosed in 3 siblings using clinical and biochemical characteristics, HFE and ceruloplasmin mutational analysis, liver biopsy, brain-, liver-, and heart-MRI. For iron depletion, a starting dose of deferasirox 7.5 mg/kg/day was increased to 15 mg/kg/day and maintained at 4-7.5 mg/kg/day with a patient follow-up for 2 years. A novel homozygous mutation of the ceruloplasmin gene on chromosome 3 (3q23-q25, exon 12, G708S) was found. Iron was selectively and successfully removed by long-term therapy with deferasirox, as confirmed by follow-up liver biopsies, normalisation of serum ferritin concentrations, and improved glucose metabolism. Unexpectedly, iron depletion ameliorated anaemia. Low-dose deferasirox is an effective and safe long-term treatment option for patients with ACP.

Transient elastography compared to serum markers to predict liver fibrosis in a cohort of Chinese patients with chronic hepatitis B.

BACKGROUND AND AIM: Liver stiffness measurement (LSM) using transient elastography (FibroScan) is a useful tool to assess fibrosis in various chronic liver diseases. However, studies were mainly performed in Western countries and largely focused on chronic hepatitis C (CHC). We therefore carried out a multicenter study to validate the accuracy of LSM in the assessment of liver fibrosis in a large cohort of Chinese patients with chronic hepatitis B (CHB). METHODS: We compared LSM results to histological staging and serum fibrosis markers (five direct markers, APRI and FIB-4) using Spearman correlation analysis and area under receiver operating characteristic (ROC) curves (AUROCs). RESULTS: Four hundred sixty-nine patients were enrolled and eligible for statistical analysis. LSM in F0 to F4 was 5.5 ± 1.7, 5.8 ± 2.2, 7.6 ± 3.4, 14.5 ± 10.8, and 22.3 ± 13.6 kPa, respectively (correlation with fibrosis stage r = 0.522, P < 0.001). AUROC for LSM to correctly allocate patients to histological fibrosis stage ≥ F2, ≥ F3, and F4 was 0.82, 0.88, and 0.90, respectively. LSM outperformed serum fibrosis markers for detection of fibrosis F ≥ 2 and F4. Patients with ALT levels 1-5x and > 5x the upper limit of normal values had significantly higher stiffness values than stage-matched patients with normal alanine aminotransferase. CONCLUSION: Transient elastography is a reliable noninvasive technique to predict significant liver fibrosis in Chinese patients with CHB, being superior to current biomarker panels. However, enhanced inflammatory activity can lead to elevated stiffness values unrelated to histological fibrosis stage.

Thyroid-associated orbitopathy is linked to gastrointestinal autoimmunity.

Common autoimmune disorders tend to co-exist in the same subjects and cluster in families. The objective of this study was to determine the prevalence of autoimmune co-morbidity in patients with autoimmune thyroid disease (AITD) with and without thyroid-associated orbitopathy (TAO). This was a cross-sectional study conducted at an academic tertiary referral centre. Of 1310 patients with AITD [n = 777 or 59% with Graves' disease (GD) and n = 533, 41% with Hashimoto's thyroiditis (HT)] followed at a specialized joint thyroid-eye out-patient clinic, 176 (13·4%) had an adult type of the autoimmune polyglandular syndrome, 129 (9·8%) type 1 diabetes, 111 (8·5%) coeliac disease, 60 (4·6%) type A autoimmune gastritis, 57 (4·4%) vitiligo and 25 (1·9%) Addison's disease. Coeliac disease and autoimmune gastritis were associated positively with GD [odds ratio (OR) = 2·18; P = 0·002 and OR = 6·52; P < 0·001], whereas type 1 diabetes, Addison's disease, autoimmune primary hypogonadism, alopecia areata, rheumatoid arthritis and Sjögren's syndrome were 'protective' for GD and thus linked to HT, OR = 0·49 (P < 0·001), 0·06 (P < 0·001), 0·25 (P < 0·001), 0·50 (P = 0·090) and 0·32 (P = 0·003), respectively. Of 610 (46·6%) AITD patients with TAO, 584 (95·7%) and 26 (4·3%) had GD and HT, respectively (P < 0·001). TAO was most prevalent in GD patients with coeliac disease (94%, OR = 1·87, P < 0·001). Multivariate analysis showed high OR for coeliac disease and autoimmune gastritis (3·4 and 4·03, both P < 0·001) pertaining to the association with TAO while type 1 diabetes, Addison's disease and alopecia areata were protective for TAO. In patients with TAO, coeliac disease is the most prevalent co-morbid autoimmune condition and rates are increased compared to GD patients without TAO.

Ex vivo analysis of resident hepatic pro-inflammatory CD1d-reactive T cells and hepatocyte surface CD1d expression in hepatitis C.

Hepatic CD1d-restricted and natural killer T-cell populations are heterogeneous. Classical 'type 1' α-galactosylceramide-reactive CD1d-restricted T cells express 'invariant' TCRα ('iNKT'). iNKT dominating rodent liver are implicated in inflammation, including in hepatitis models. Low levels of iNKT are detected in human liver, decreased in subjects with chronic hepatitis C (CHC). However, high levels of human hepatic CD161(±) CD56(±) noninvariant pro-inflammatory CD1d-restricted 'type 2' T cells have been identified in vitro. Unlike rodents, healthy human hepatocytes only express trace and intracellular CD1d. Total hepatic CD1d appears to be increased in CHC and primary biliary cirrhosis. Direct ex vivo analysis of human intrahepatic lymphocytes (IHL), including matched ex vivo versus in vitro expanded IHL, demonstrated detectable noninvariant CD1d reactivity in substantial proportions of HCV-positive livers and significant fractions of HCV-negative livers. However, α-galactosylceramide-reactive iNKT were detected only relatively rarely. Liver CD1d-restricted IHL produced IFNγ, variable levels of IL-10 and modest levels of Th2 cytokines IL-4 and IL-13 ex vivo. In a novel FACS assay, a major fraction (10-20%) of hepatic T cells rapidly produced IFNγ and up-regulated activation marker CD69 in response to CD1d. As previously only shown with murine iNKT, noninvariant human CD1d-specific responses were also augmented by IL-12. Interestingly, CD1d was found selectively expressed on the surface of hepatocytes in CHC, but not those CHC subjects with history of alcohol usage or resolved CHC. In contrast to hepatic iNKT, noninvariant IFNγ-producing type 2 CD1d-reactive NKT cells are commonly detected in CHC, together with cognate ligand CD1d, implicating them in CHC liver damage.

Identification of tissue transglutaminase as the autoantigen of celiac disease.

Celiac disease is characterized by small intestinal damage with loss of absorptive villi and hyperplasia of the crypts, typically leading to malabsorption. In addition to nutrient deficiencies, prolonged celiac disease is associated with an increased risk for malignancy, especially intestinal T-cell lymphoma. Celiac disease is precipitated by ingestion of the protein gliadin, a component of wheat gluten, and usually resolves on its withdrawal. Gliadin initiates mucosal damage which involves an immunological process in individuals with a genetic predisposition. However, the mechanism responsible for the small intestinal damage characteristic of celiac disease is still under debate. Small intestinal biopsy with the demonstration of a flat mucosa which is reversed on a gluten-free diet is considered the main approach for diagnosis of classical celiac disease. In addition, IgA antibodies against gliadin and endomysium, a structure of the smooth muscle connective tissue, are valuable tools for the detection of patients with celiac disease and for therapy control. Incidence rates of childhood celiac disease range from 1:300 in Western Ireland to 1:4700 in other European countries, and subclinical cases detected by serological screening revealed prevalences of 3.3 and 4 per 1000 in Italy and the USA, respectively. IgA antibodies to endomysium are particularly specific indicators of celiac disease, suggesting that this structure contains one or more target autoantigens that play a role in the pathogenesis of the disease. However, the identification of the endomysial autoantigen(s) has remained elusive. We identified tissue transglutaminase as the unknown endomysial autoantigen. Interestingly, gliadin is a preferred substrate for this enzyme, giving rise to novel antigenic epitopes.

Isolation and characterization of circulating tissue transglutaminase-specific T cells in coeliac disease.

Tissue transglutaminase (TG2) was identified as the humoral autoantigen in coeliac disease, but whether it can also serve as T cell autoantigen is still unknown. We aimed, therefore, to firstly explore the presence of TG2-specific T cells in peripheral blood of ten adult patients (four active, i.e. carrying both serological and histological features of the disease; four treated, i.e. with proven mucosal recovery and disappearance of specific antibodies after an adequate period of gluten free diet; and two potential coeliacs, i.e. carrying the serological stigmata of the disease, but not the intestinal lesions), and four healthy controls (two carrying the HLA-DQ2 haplotype of susceptibility to the disease), and secondly to carry out a detailed in vitro characterization of the isolated antigen-specific T cells. T cell lines were first established by means of weekly stimulation with human recombinant TG2 followed by generation of T cell clones through distribution of T cells on plates at one cell/well limiting dilution and further rounds of stimulation. Antigen specificity and HLA-DQ2 restriction were both assessed by evaluating the proliferative response to TG2 in the absence and presence of human sera blocking HLA-DQ2 molecules, after exclusion of impurities in the antigen preparation. Immune phenotyping of T cell clones was performed by flow cytometry, and the expression of IL-1â, IL-4, IL-6, IL-10, IL-12, TGF-beta, IFN-gamma and TNF-alpha was determined by ELISA assay on the supernatants of these clones. A total of 91 T cell clones were isolated from the three HLA-DQ2-positive, active patients, but none from the other patients and controls. The immune phenotyping showed that the majority of them (85.7 percent) were CD3/CD4+ and only a small percentage (14.3 percent) were CD3/CD8+, all carried the TCR alphabeta, and had a memory phenotype. The cytokine profile showed high levels of IFN-gamma and IL-6 that, together with the absence of IL-4, placed these T cell clones in the T helper type 1-like category. Further in vitro analysis was carried out on 32/91 CD4+ clones and showed a specific and dose-dependent proliferative response towards TG2 and an HLA-DQ2 restriction. Finally, when incubating duodenal mucosal specimens of treated patients with the supernatant of TG2-specific T cell clones, characteristic disease lesions were found, indicating a role for TG2-specific cellular immune response in the pathogenesis of coeliac disease.

Gliadin-primed CD4+CD45RBlowCD25- T cells drive gluten-dependent small intestinal damage after adoptive transfer into lymphopenic mice.

BACKGROUND AND AIMS: Coeliac disease is a common small intestinal inflammatory disorder that results from a breach of intestinal tolerance to dietary gluten proteins, driven by gluten-reactive effector T cells. We aimed to assess the pathogenic role of gluten-reactive T cells and to generate a model of gluten-induced enteropathy. METHODS: CD4+CD25- T cell fractions were adoptively transferred into lymphopenic mice, leading to "baseline" small intestinal inflammation. RESULTS: Rag1-/- recipients of gliadin-presensitised CD4+CD45RBlowCD25- T cells, but not CD4+CD45RBhigh naive T cells, gained less weight and suffered from more severe duodenitis when challenged with oral gluten than recipients on gluten-free diet, or recipients of control (ovalbumin)-presensitised T cells. This was accompanied by deterioration of mucosal histological features characteristic of coeliac disease, and increased Th1/Th17 cell polarisation in the duodenum and the periphery. Interestingly, reintroduction of a gluten-free diet led to weight gain, improvement of histological duodenitis, and a decrease in duodenal interferon gamma and interleukin 17 transcripts. Moreover, B cell-competent nude recipients of gliadin-presensitised CD4+CD45RBlowCD25- T cells produced high levels of serum anti-gliadin immunoglobulin A (IgA) and IgG1/IgG2c only when challenged with oral gluten. CONCLUSIONS: CD4+ T cell immunity to gluten leads to a breach of oral gluten tolerance and small intestinal pathology in lymphopenic mice, similar to human coeliac disease. This model will be useful for the study of coeliac disease pathogenesis, and also for testing novel non-dietary therapies for coeliac disease.

Rationale and targets for antifibrotic therapies.

We have made striking progress in our understanding of the biochemistry and cell biology that underlies liver fibrosis and cirrhosis, including the development of strategies and agents to prevent and reverse fibrosis and incipient cirrhosis. However, translation of this knowledge into clinical practice has been hampered by the limitation of many in vitro and in vivo models to confirm mechanisms and to test antifibrotic agents, as well as the lack of sensitive methodologies to quantify the degree of liver fibrosis and the dynamics of fibrosis progression or reversal. Furthermore, while cirrhosis and subsequent decompensation are accepted hard clinical end-points, fibrosis and fibrosis progression alone are merely plausible surrogates for future clinical deterioration. This review focuses on basic mechanisms that underlay liver fibrosis progression and reversal and optimized strategies for preclinical antifibrotic drug development and validation. Therapies include several drugs that are of proven safety for other indications, agents that interfere with major fibrogenic or fibrolytic mechanisms, targeted drug delivery to the fibrogenic liver cells, and their potential combinations with hepatocyte or stem cell replenishment.

The hedgehog pathway regulates remodelling responses to biliary obstruction in rats.

BACKGROUND: Chronic biliary obstruction provokes fibrosis and accumulation of immature ductular cells. This fibroductular reaction resolves following biliary decompression, suggesting that it may also be involved in the repair of biliary damage. The hedgehog (Hh) pathway becomes activated in liver after bile duct ligation (BDL), and might modulate hepatic remodelling because Hh ligands are potent morphogens. OBJECTIVE: To study the induction of the Hh pathway during progression and resolution of biliary fibrosis, and to clarify whether Hh signalling regulates accumulation of bile duct progenitor cells. DESIGN AND MAIN OUTCOME MEASURES: Livers from rats with BDL were examined by quantitative real-time polymerase chain reaction analysis and immunohistochemistry to identify factors that might stimulate Hh signalling. BDL rats were subjected to Roux-en-Y hepaticojejunostomy (R-Y) to relieve biliary obstruction in order to determine whether these factors and Hh signalling declined as ductular populations and concomitant fibrosis regressed. Cultures of immature ductular cells were treated with putative Hh inducers and Hh ligands to confirm their functional relevance. RESULTS: BDL increased expression of platelet-derived growth factor-BB (PDGF-BB) and sonic hedgehog (Shh), downregulated hedgehog-interacting protein (Hip), activated Hh signalling, and expanded populations of Hh-responsive ductular cells that expressed pancyotkeratin, a liver progenitor cell marker. After R-Y, Hip remained suppressed, expression of PDGF-BB and Shh gradually declined, and populations of hedgehog-responsive ductular cells regressed. In cultured ductular cells, PDGF-BB treatment induced Shh expression, and incubation with Shh inhibited apoptotic activity. CONCLUSIONS: These results identify a mechanism for activation of the Hh pathway during cholestasis and suggest that Hh signalling regulates ductular cell accumulation after biliary injury.

The antifibrotic potential of a sustained release formulation of a PDGFß-receptor targeted rho kinase inhibitor.

Rho kinase activity in hepatic stellate cells (HSCs) is associated with activation, transformation and contraction of these cells, leading to extracellular matrix production and portal hypertension in liver cirrhosis. Inhibition of rho kinase activity can reduce these activities, but may also lead to side effects, for instance systemic hypotension. This can be circumvented by liver-specific delivery of a rho kinase inhibitor to effector cells. Therefore, we targeted the rho kinase inhibitor Y27632 to the key pathogenic cells in liver fibrosis, i.e. myofibroblasts including activated HSCs that highly express the PDGFß-receptor, using the drug carrier pPB-MSA. This carrier consists of mouse serum albumin (MSA) covalently coupled to several PDGFßR-recognizing moieties (pPB). We aimed to create a prolonged release system of such a targeted construct, by encapsulating pPB-MSA-Y27632 in biodegradable polymeric microspheres, thereby reducing short-lasting peak concentrations and the need for frequent administrations. Firstly, we confirmed the vasodilating potency of PDGFß-receptor targeted Y27632 in vitro in a contraction assay using HSCs seeded on a collagen gel. We subsequently demonstrated the in vivo antifibrotic efficacy of pPB-MSA-Y27632-loaded microspheres in the Mdr2-/- mouse model of progressive biliary liver fibrosis. A single subcutaneous microsphere administration followed by organ harvest one week later clearly attenuated liver fibrosis progression and significantly suppressed the expression of fibrosis related genes, such as several collagens, profibrotic cytokines and matrix metalloproteinases. In conclusion, we demonstrate that polymeric microspheres are suitable as drug delivery system for the sustained systemic delivery of targeted protein constructs with antifibrotic potential, such as pPB-MSA-Y27632. This formulation appears suitable for the sustained treatment of liver fibrosis and possibly other chronic diseases.

Pharmacokinetics of a sustained release formulation of PDGFß-receptor directed carrier proteins to target the fibrotic liver.

Liver fibrogenesis is associated with excessive production of extracellular matrix by myofibroblasts that often leads to cirrhosis and consequently liver dysfunction and death. Novel protein-based antifibrotic drugs show high specificity and efficacy, but their use in the treatment of fibrosis causes a high burden for patients, since repetitive and long-term parenteral administration is required as most proteins and peptides are rapidly cleared from the circulation. Therefore, we developed biodegradable polymeric microspheres for the sustained release of proteinaceous drugs. We encapsulated the drug carrier pPB-HSA, which specifically binds to the PDGFßR that is highly upregulated on activated myofibroblasts, into microspheres composed of hydrophilic multi-block copolymers composed of poly(l-lactide) and poly ethylene glycol/poly(ϵ-caprolactone), allowing diffusion-controlled release. Firstly, we estimated in mice with acute fibrogenesis induced by a single CCl4 injection the half-life of I125-labeled pPB-HSA at 40 min and confirmed the preferential accumulation in fibrotic tissue. Subsequently, we determined in the Mdr2 −/− mouse model of advanced biliary liver fibrosis how the subcutaneously injected microspheres released pPB-HSA into both plasma and fibrotic liver at 24 h after injection, which was maintained for six days. Although the microspheres still contained protein at day seven, pPB-HSA plasma and liver concentrations were decreased. This reduction was associated with an antibody response against the human albumin-based carrier protein, which was prevented by using a mouse albumin-based equivalent (pPB-MSA). In conclusion, this study shows that our polymeric microspheres are suitable as sustained release formulation for targeted protein constructs such as pPB-HSA. These formulations could be applied for the long-term treatment of chronic diseases such as liver fibrosis.

Radioimmunoassay for the carboxy-terminal cross-linking domain of type IV (basement membrane) procollagen in body fluids. Characterization and application to collagen type IV metabolism in fibrotic liver disease.

The carboxy-terminal cross-linking domain (NCl) of type IV procollagen was isolated from human placenta and used for the production of polyclonal and monoclonal antibodies. Purity of the antigen and specificity of the antibodies were verified by Western blotting and radioimmunoassays. A radioimmunoassay was developed using rabbit antiserum. Intra- and interassay coefficients of variation were 4.7% and 5.8%, respectively; recovery of NCl added to serum and bile was 95-105%. NCl concentration in sera of healthy volunteers was 6 +/- 2.9 ng/ml (mean +/- 2.5 SD) and was elevated up to 18 ng in sera of patients with autoimmune or metastatic tumor disease and up to 240 ng in sera of patients with fibrogenic liver disease. Substantial amounts of antigen were also found in bile, urine, and ascites. 67% of serum antigens eluted from an agarose A5M column with an apparent molecular weight of 60 kD and 23% with a molecular weight of 90 and 150 kD, well below the molecular weight of type IV procollagen (550 kD). Serum NCl is apparently derived from the degradation of basement membrane collagen. The time course of NCl concentrations in sera of patients with fibrogenic liver disease showed no correlation with the serum concentration of the amino-terminal procollagen type III peptide, a marker of hepatic collagen biosynthesis. A decline of serum NCl levels along with elevated serum procollagen type III peptides apparently indicates bad prognosis in fibrogenic liver disease. The radioimmunoassay for NCl is a useful tool for studying type IV collagen metabolism in conditions causing remodeling or breakdown of basement membranes.

A prospective comparative study of five measures of gluten-free diet adherence in adults with coeliac disease.

BACKGROUND: Increasing numbers of individuals are now being diagnosed with coeliac disease. The only accepted treatment for coeliac disease is lifelong adherence to a strict gluten-free diet (GFD). Individuals' ability to adhere to the GFD varies, but systematic studies guiding the assessment of adherence are currently lacking. AIM: We sought to compare the predictive value of self-report and four serologic tests compared to expert nutritionist evaluation. METHODS: In all, 154 individual adults with biopsy-proven coeliac disease rated their adherence to the GFD on a Likert scale. Serum antibody titres of IgA anti-tissue transglutaminase, and IgA and IgG anti-deamidated gliadin peptides were determined. Using anova and ROC analyses, results were compared to a standardized evaluation by an expert nutritionist blinded to the participants' self-rated adherence and serology results. RESULTS: All serologic measures as well as participant reported adherence were significantly associated with GFD adherence as assessed by expert nutritionist evaluation. However, on ROC analysis no measure performed satisfactorily. The performance of serologic testing, but not self-report, improved with increased time on the GFD. CONCLUSION: Although current serologic tests have very high sensitivities and specificities for the diagnosis of coeliac disease, they cannot replace trained nutritionist evaluation in the assessment of GFD adherence.

Herbal medicine in the treatment of liver diseases.

Herbal drugs have become increasingly popular and their use is widespread. Licensing regulations and pharmacovigilance regarding herbal products are still incomplete and clearcut proof of their efficacy in liver diseases is sparse. Nevertheless, a number of herbals show promising activity including silymarin for antifibrotic treatment, phyllantus amarus in chronic hepatitis B, glycyrrhizin to treat chronic viral hepatitis, and a number of herbal combinations from China and Japan that deserve testing in appropriate studies. Apart from therapeutic properties, reports are accumulating about liver injury after the intake of herbals, including those advertised for liver diseases. Acute and/or chronic liver damage occurred after ingestion of some Chinese herbs, herbals that contain pyrrolizidine alkaloids, germander, greater celandine, kava, atractylis gummifera, callilepsis laureola, senna alkaloids, chaparral and many others. Since the evidence supporting the use of botanicals to treat chronic liver diseases is insufficient and only few of them are well standardised and free of potential serious side effects, most of these medications are not recommended outside clinical trials. Particularly with regard to the latter, adequately powered randomised-controlled clinical trials with well-selected end points are needed to assess the role of herbal therapy for liver diseases.

The good and the bad collagens of fibrosis - Their role in signaling and organ function.

Usually the dense extracellular structure in fibrotic tissues is described as extracellular matrix (ECM) or simply as collagen. However, fibrosis is not just fibrosis, which is already exemplified by the variant morphological characteristics of fibrosis due to viral versus cholestatic, autoimmune or toxic liver injury, with reticular, chicken wire and bridging fibrosis. Importantly, the overall composition of the ECM, especially the relative amounts of the many types of collagens, which represent the most abundant ECM molecules and which centrally modulate cellular functions and physiological processes, changes dramatically during fibrosis progression. We hypothesize that there are good and bad collagens in fibrosis and that a change of location alone may change the function from good to bad. Whereas basement membrane collagen type IV anchors epithelial and other cells in a polarized manner, the interstitial fibroblast collagens type I and III do not provide directional information. In addition, feedback loops from biologically active degradation products of some collagens are examples of the importance of having the right collagen at the right place and at the right time controlling cell function, proliferation, matrix production and fate. Examples are the interstitial collagen type VI and basement membrane collagen type XVIII. Their carboxyterminal propeptides serve as an adipose tissue hormone, endotrophin, and as a regulator of angiogenesis, endostatin, respectively. We provide an overview of the 28 known collagen types and propose that the molecular composition of the ECM in fibrosis needs careful attention to assess its impact on organ function and its potential to progress or reverse. Consequently, to adequately assess fibrosis and to design optimal antifibrotic therapies, we need to dissect the molecular entity of fibrosis for the molecular composition and spatial distribution of collagens and the associated ECM.