Computerized three-dimensional study of a rotavirus model of biliary atresia: comparison with human biliary atresia

Rodent models of cholestatic liver disease: A practical guide for translational research

Cholestatic liver disease denotes any situation associated with impaired bile flow concomitant with a noxious bile acid accumulation in the liver and/or systemic circulation. Cholestatic liver disease can be subdivided into different types according to its clinical phenotype, such as biliary atresia, drug-induced cholestasis, gallstone liver disease, intrahepatic cholestasis of pregnancy, primary biliary cholangitis and primary sclerosing cholangitis. Considerable effort has been devoted to elucidating underlying mechanisms of cholestatic liver injuries and explore novel therapeutic and diagnostic strategies using animal models. Animal models employed according to their appropriate applicability domain herein play a crucial role. This review provides an overview of currently available in vivo animal models, fit-for-purpose in modelling different types of cholestatic liver diseases. Moreover, a practical guide and workflow is provided which can be used for translational research purposes, including all advantages and disadvantages of currently available in vivo animal models.

Aetiology of biliary atresia: what is actually known?

Biliary atresia (BA) is a rare disease of unknown etiology and unpredictable outcome, even when there has been timely diagnosis and exemplary surgery. It has been the commonest indication for liver transplantation during childhood for the past 20 years. Hence much clinical and basic research has been directed at elucidating the origin and pathology of BA. This review summarizes the current clinical variations of BA in humans, its occasional appearance in animals and its various manifestations in the laboratory as an experimental model.

Biliary atresia: the animal models

Biliary atresia (BA) is a progressive fibrosing process of the neonatal biliary tree and liver, of unknown origin, and an as-yet unexplained pathologic mechanism. The crucial point is to elucidate the origin of this rare disease to change palliative surgery to etiology-related procedures. Patient-based research can only begin at the time of the Kasai procedure and does not allow retracing of the pathology back to its origin. Basic research has focused on similar diseases in the veterinary literature and started to simulate BA in animal models. Unfortunately, even after 50 years of research, no knowledge has been gained from such models, which has led to a single clinical application. This article reviews BA in the context of the animal models available and discusses whether future studies are promising or futile.

Biliary atresia: interdisciplinary initiatives focus on a rare disease

During the last decade, biliary atresia (BA) has attained more interest and the frequency of BA-related publications has increased continuously. Pediatric hepatologists and pediatric surgeons are very active in improving diagnosis and treatment modalities of BA patients, in order to prolong the survival rate of their native liver. Together with transplant surgeons, the bridging of BA patients to liver transplantation (LTx) becomes optimized and as a consequence of this interdisciplinary approach, the overall survival of babies with BA has already reached 90%. Furthermore, basic research into the still unknown origin of BA has advanced, and numerous scientific programs have already linked together. The overriding interest is to discover at least BA's etiology and to turn the treatment of BA patients from a symptomatic to a causative approach. Interdisciplinary and international programs are mandatory and already existing initiatives in Europe, the United States and Japan are going to coordinate their registries, clinical trials and basic research studies for the benefit of the patients and solve the riddle of BA.

Gene expression profile of the infective murine model for biliary atresia

One hypothesis of the pathogenesis of biliary atresia (BA) is a virus-induced and immune-mediated injury to bile duct cells as mimicked in the rotavirus-induced murine model. This theory is supported by studies showing a predominant T helper cell response type 1-like phenotype of inflammation with increased interferon gamma-induced chemokines in the liver of humans and mice suffering from BA. Recent gene expression profiling studies using microarray analysis showed the induction of a proinflammatory state in human liver specimens with high analogies in extrahepatic biliary tissue of BA mice. The aim of the present study was a microarray analysis of gene expression in the liver of Balb/c mice, comparing infected mice that show the phenotype of BA versus infected mice without symptoms, thus trying to elucidate genes that are not related to the viral origin of this model, but to the specific pathogenesis of the clinical picture of BA. Fifteen mug of RNA, each of three BA-positive and three BA-negative mice, were pooled and comparatively hybridized to spotted cDNA microarrays containing 250 key genes with high relevance to immunological settings. We identified the 40 genes most differentially expressed in mice with and without BA. The majority of genes with higher expression in BA-positive mice encoded proinflammatory cytokines involved in the Th1 pathway, such as CCL2, CCL5, CCR5, CXCL10, CCL2, IL1F5 and in apoptosis, such as DDR3 and granzyme A and B. In this initial study of the molecular characterization of our RRV-induced BA mouse model system, we also found potential novel candidates important to BA etiology, such as growth hormone receptor and insulin-like growth factor. Of particular interest, very low expression of TIMD2 was observed in BA-positive mice. TIMD2 plays a critical role in the regulation of a Th2-type response through the inhibition of IFN gamma.