Bioengineered Liver Cell Models of Hepatotropic Infections.

Hepatitis viruses and liver-stage malaria are within the liver infections causing higher morbidity and mortality rates worldwide. The highly restricted tropism of the major human hepatotropic pathogens-namely, the human hepatitis B and C viruses and the Plasmodium falciparum and Plasmodium vivax parasites-has hampered the development of disease models. These models are crucial for uncovering the molecular mechanisms underlying the biology of infection and governing host-pathogen interaction, as well as for fostering drug development. Bioengineered cell models better recapitulate the human liver microenvironment and extend hepatocyte viability and phenotype in vitro, when compared with conventional two-dimensional cell models. In this article, we review the bioengineering tools employed in the development of hepatic cell models for studying infection, with an emphasis on 3D cell culture strategies, and discuss how those tools contributed to the level of recapitulation attained in the different model layouts. Examples of host-pathogen interactions uncovered by engineered liver models and their usefulness in drug development are also presented. Finally, we address the current bottlenecks, trends, and prospect toward cell models' reliability, robustness, and reproducibility.

[Clinical characteristics and distribution of peripheral T lymphocyte subsets in patients with schistosomal hepatic diseases in Suzhou City].

OBJECTIVE: To investigate the clinical characteristics and the distribution of peripheral blood T lymphocyte sub-sets in patients with schistosomal hepatic cirrhosis in Suzhou City. METHODS: A total of 32 inpatients with liver diseases due to advanced schistosomiasis at the Department of Infectious Diseases, The First Affiliated Hospital of Soochow University from January 2016 to January 2018 were recruited and assigned into the infection and non-infection groups according to presence of co-infections, and 20 old healthy volunteers served as controls. Venous blood samples were collected on the day of admission, and the proportions of CD4+ T cells, CD8+ T cells, regulatory T (Treg) cells and Th17 cells were detected in peripheral blood using flow cytometry. RESULTS: Most patients with liver disorders due to advanced schistosomiasis were admitted to hospital in Suzhou City because of portal hypertension-associated complications, with a high prevalence of co-infections (59.38%, 19/32). The proportions of peripheral CD4+ and CD8+ T cells and Th17 cells were all significantly lower in patients with liver disorders due to advanced schistosomiasis than in controls (t = -5.111, -4.470 and -2.749, all P < 0.05), and a higher proportion of Treg cells was detected in patients than in controls (t = 5.628, P < 0.05). In addition, there were significant differences among the infection group, non-infection group and controls in terms of the percentage of CD4+ T cells, CD8+ T cells, Th17 cells and Treg cells (F = 15.837, 16.594, 9.290 and 27.866, all P < 0.05). CONCLUSIONS: Portal hypertension-associated complications are predominantly seen in patients with liver diseases due to advanced schistosomiasis at admission in Suzhou City, and co-infections are common. Imbalance of peripheral T cell subsets is detected in patients with liver diseases due to advanced schistosomiasis in Suzhou City.

Genetic algorithms identify individuals with high risk of severe liver disease caused by schistosomes.

Schistosomes induce severe hepatic disease, which is fatal in 2-10% of cases, mortality being higher in cases of co-infection with HBV or HCV. Hepatic disease occurs as a consequence of the chronic inflammation caused by schistosome eggs trapped in liver sinusoids. In certain individuals, the repair process leads to a massive accumulation of fibrosis in the periportal spaces. We and others have shown that genetic variants play a crucial role in disease progression from mild to severe fibrosis and explain why hepatic fibrosis progresses rapidly in certain subjects only. We will review here published findings concerning the strategies that have been used in the analysis of hepatic fibrosis in schistosome-infected individuals, the genetic variants that have associated with fibrosis, and variants in new pathways crucial for fibrosis progression. Together, these studies show that the development of fibrosis is under the tight genetic control of various common variants with moderate effects. This polygenic control has made it possible to develop models that identify schistosome-infected individual at risk of severe hepatic disease. We discuss the performances and limitations of these models.

Opisthorchis viverrini Proteome and Host-Parasite Interactions.

The omics technologies have improved our understanding of the molecular events that underpin host-parasite interactions and the pathogenesis of parasitic diseases. In the last decade, proteomics and genomics in particular have been used to characterize the surface and secreted products of the carcinogenic liver fluke Opisthorchis viverrini and revealed important roles for proteins at the host-parasite interface to ensure that the flukes can migrate, feed and reproduce in a hostile environment. This review summarizes the advances made in this area, primarily focusing on discoveries enabled by the publication of the fluke secreted proteomes over the last decade. Protein families that will be covered include proteases, antioxidants, oncogenic proteins and the secretion of exosome-like extracellular vesicles. Roles of these proteins in host-parasite interactions and pathogenesis of fluke-induced hepatobiliary diseases, including cholangiocarcinogenesis, are discussed. Future directions for the application of this knowledge to control infection and disease will also be discussed.

Cx3cr1 deficiency in mice attenuates hepatic granuloma formation during acute schistosomiasis by enhancing the M2-type polarization of macrophages.

Acute schistosomiasis is characterized by pro-inflammatory responses against tissue- or organ-trapped parasite eggs along with granuloma formation. Here, we describe studies in Cx3cr1(-/-) mice and demonstrate the role of Cx3cr1 in the pathoetiology of granuloma formation during acute schistosomiasis. Mice deficient in Cx3cr1 were protected from granuloma formation and hepatic injury induced by Schistosoma japonicum eggs, as manifested by reduced body weight loss and attenuated hepatomegaly along with preserved liver function. Notably, S. japonicum infection induced high levels of hepatic Cx3cr1 expression, which was predominantly expressed by infiltrating macrophages. Loss of Cx3cr1 rendered macrophages preferentially towards M2 polarization, which then led to a characteristic switch of the host immune defense from a conventional Th1 to a typical Th2 response during acute schistosomiasis. This immune switch caused by Cx3cr1 deficiency was probably associated with enhanced STAT6/PPAR-γ signaling and increased expression of indoleamine 2,3-dioxygenase (IDO), an enzyme that promotes M2 polarization of macrophages. Taken together, our data provide evidence suggesting that CX3CR1 could be a viable therapeutic target for treatment of acute schistosomiasis.

Recombinant adeno-associated virus-mediated inhibition of microRNA-21 protects mice against the lethal schistosome infection by repressing both IL-13 and transforming growth factor beta 1 pathways.

UNLABELLED: Schistosomiasis is a serious parasitic disease in humans, which can lead to liver fibrosis and death. Accumulating evidence indicated that targeting the deregulated microRNAs (miRNAs) could mitigate disease outcomes. Here, we showed that progressive hepatic schistosomiasis caused elevation of miR-21 and efficient and sustained inhibition of miR-21 by using highly hepatic tropic adeno-associated virus serotype 8 (rAAV8), which protected mice against lethal schistosome infection through attenuation of hepatic fibrosis (HF). We demonstrated an additive role of interleukin (IL)-13 and transforming growth factor beta 1 (TGF-ß1) in up-regulating miR-21 expression in hepatic stellate cells (HSCs) by activation of mothers against decapentaplegic (SMAD) proteins. Furthermore, down-regulation of miR-21 in HSCs reversed HF by enhancing SMAD7 expression, thus repressing TGF-ß1/Smad and IL-13/Smad pathways. CONCLUSION: This study suggests the mechanism of IL-13-mediated schistosomiasis HF by up-regulation of miR-21 and highlights the potential of rAAV8-mediated miR-21 inhibition as a therapeutic intervention for hepatic fibrotic diseases, such as schistosomiasis.

Hepatic visceral larva migrans.

Visceral larva migrans (VLM) is a systemic manifestation of migration of second stage larvae of nematodes through the tissue of human viscera. It is not uncommon but is underdiagnosed in developing countries. The liver is the most common organ to be involved due to its portal venous blood supply. The imaging findings are subtle and differentiation from hepatocellular carcinoma (HCC), metastases, cystic mesenchymal hamartoma and granulomatous diseases is difficult. This case report highlights the imaging features of hepatic lesions of VLM along with clinical and laboratory data which help in clinching the diagnosis.

Genetic analysis of human predisposition to hepatosplenic disease caused by schistosomes reveals the crucial role of connective tissue growth factor in rapid progression to severe hepatic fibrosis.

Schistosome worms inhabit mammalian mesenteric veins. Their eggs cause chronic inflammation, which progresses to periportal fibrosis in 5 to 30% of cases, increasing portal blood pressure and leading to esophageal varices. Episodes of bleeding cause hepatic necrosis and may ultimately lead to hepatic failure and the death of the patient. Schistosome infections can also cause pulmonary hypertension and heart failure. The mechanisms of fibrogenesis and fibrolysis are beginning to be unraveled, but it remains unclear why disease occurs only in certain subjects, as also observed for other types of chronic liver inflammation, as in hepatitis C or B. We summarize here the results that showed that fibrosis progression is determined by a genetic locus on chromosome 6. The CCN2 gene at this locus, encodes CTGF that is a crucial regulator of fibrosis. Two groups of CCN2 polymorphisms independently modulate the progression of hepatic fibrosis. These results were obtained in an Asian population, but were extended to humans living in Africa and South America and are presently tested in liver fibrosis of other etiological origins.

Imaging techniques and histology in the evaluation of liver fibrosis in hepatosplenic schistosomiasis mansoni in Brazil: a comparative study.

Few publications have compared ultrasound (US) to histology in diagnosing schistosomiasis-induced liver fibrosis (LF); none has used magnetic resonance (MR). The aim of this study was to evaluate schistosomal LF using these three methods. Fourteen patients with hepatosplenic schistosomiasis admitted to hospital for surgical treatment of variceal bleeding were investigated. They were submitted to upper digestive endoscopy, US, MR and wedge liver biopsy. The World Health Organization protocol for US in schistosomiasis was used. Hepatic fibrosis was classified as absent, slight, moderate or intense. Histology and MR confirmed Symmers' fibrosis in all cases. US failed to detect it in one patient. Moderate agreement was found comparing US to MR; poor agreement was found when US or MR were compared to histology. Re-classifying LF as only slight or intense created moderate agreement between imaging techniques and histology. Histomorphometry did not separate slight from intense LF. Two patients with advanced hepatosplenic schistosomiasis presented slight LF. Our data suggest that the presence of the characteristic periportal fibrosis, diagnosed by US, MR or histology, associated with a sign of portal hypertension, defines the severity of the disease. We conclude that imaging techniques are reliable to define the presence of LF but fail in grading its intensity.

[Liver injury in visceral leishmaniasis in children: systematic review]. / Alteraciones hepáticas en la Leishmaniasis Visceral (Kalazar) en niños: revisión sistemática de la literatura.

UNLABELLED: Visceral Leisshimaniosis or Kalazar is a parasitic infection caused by Leishimania Donovani subspecies. It is transmitted by phlebotomineos and may lead to liver and spleen enlargements as well as immunological impairment. Sometimes it is described liver injury simulating acute or chronic viral hepatitis and even portal hypertension. The liver injury makes difficult the diffencial diagnosis of Kalazar and other liver diseases in endemic regions. OBJECTIVE: To define and clarify the liver injury spectrum described in published cases reports. METHODS: Systematic revision of published data on Kalazar and liver injury using the following databank: LILACS, MEDLINE and EMBASE. Only paper published in French, English, Portuguese and Spanish were taken into consideration. The procedures for systematic review recommended by the NHS Centre for Reviews and Dissemination, University of Cork, were adopted. The paper quality classification was based on the number of reported variables previously defined in our study RESULTS: Only 11/28 (55%) publications were included in our analysis because they filled the minimal required data. Acute and chronic liver disease were well documented in these articles. Serum albumin and prothombine time were associated with severity of liver disease (P < .05). CONCLUSION: "Liver involvement, even when it is severe, may occur at tha begining of the disease. Kalazar should be considered as a differential diagnosis of cholestasis, acute and chronic liver injury as well as portal hypertension in children.

Alteraciones hepáticas en la Leishmaniasis Visceral (Kalazar) en niños: revisión sistemática de la literatura / Liver injury in visceral Leishmaniasis in Children: systematic review

La Leishmaniasis Visceral o Kalazar es una infección parasitaria causada por subespecies del género Leishmania donovani y transmitida por insectos flebotomíneos. Puede evolucionar con compromiso hepático caracterizado por citólisis severa, colestasis, hipertensión portal, hepatomegalia persistente y fibrosis hepática. Estos tipos de presentaciones dificultan el diagnóstico y agravan el pronostico. Se admite que la extensión y frecuencia de este compromiso hepático han sido poco evaluados. Objetivo: Sistematizar las alteraciones hepáticas de Kalazar en la infancia descritas en relatos de casos publicados. Metodología: revisión sistemática de la literatura utilizando las bases de datos LILACS, MEDLINE y EMBASE. Se incluyeron artículos en portugués, español, inglés y francés. Se siguieron los procedimientos de revisión sistemática recomendados por el NHS Centre for Reviews and Dissemination, University of Cork. La clasificación de los artículos (relatos de casos) se basó en la cantidad de información de cada relato de caso en relación a las variables previamente sistematizadas en este estudio. Resultados: 11 (un 55%) artículos fueron incluidos abarcando 28 relatos de casos. La albúmina sérica y el tiempo de protrombina mostraron una asociación con la evolución de la enfermedad: (p = 0,05). Conclusiones: el compromiso epático, incluso grave, puede ocurrir al inicio de la enfermedad. El Kalazar debe ser considerado en el diagnóstico diferencial de hepatitis asociadas a fiebre prolongada, así como en síndromes colestásicos en la infancia en áreas endémicas para la enfermedad.

Visceral Leisshimaniosis or Kalazar is a parasitic infection caused by Leishimania Donovani subspecies. It is transmitted by phlebotomineos and may lead to liver and spleen enlargements as well as immunological impairment. Sometimes it is described liver injury simulating acute or chronic viral hepatitis and even portal hypertension. The liver injury makes difficult the diffencial diagnosis of Kalazar and other liver diseases in endemic regions. Objective: To define and clarify the liver injury spectrum described in published cases reports. Methods: Systematic revision of published data on Kalazar and liver injury, using the following databank: LILACS, MEDLINE and EMBASE. Only paper published in French, English, Portuguese and Spanish were taken into consideration. The procedures for systematic review recommended by the NHS Centre for Reviews and Dissemination, University of Cork, were adopted. The paper quality classification was based on the number of reported variables previously defined in our study. Results: Only 11/ 28 (55%) publications were includedin our analysis because they filled the minimal required data. Acute and chronic liver disease were well documented in these articles. Serum albumin and prothombine time were associated with severity of liver disease (P< .05). Conclusion: “Liver involvement, even when it is severe, may occur at tha begining of the disease. Kalazar should be considered as a differential diagnosis of cholestasis, acute and chronic liver injury, as well as portal hypertension in children.

[Re-understanding of liver cirrhosis induced by Schistosomiasis japonica].

Whether the hepatic pipestem fibrosis induced by schistosomiasis japonica can result in cirrhosis, confusion exists among parasitologists in China. Evidence from national and international pathologists and clinicians confirmed that the pipestem fibrosis could develop into cirrhosis undoubtedly. Owing to different pathogenic causes, the characters of cirrhosis are different. To re-understand cirrhosis induced by Schistosomiasis japonica is of significance for the diagnosis and treatment of the advanced patient.

Hepatic and intestinal schistosomiasis after orthotopic liver transplant.

Schistosomiasis affects 200 to 250 million people worldwide. Hepatic schistosomiasis is a well-recognized cause of chronic liver disease and portal hypertension. There are no previous reports of schistosomiasis post liver transplantation. We report on 2 cases of schistosomiasis in liver transplant recipients--a case of gastric schistosomiasis and a case of hepatic schistosomiasis. A discussion of the pathology of schistosomal infection and a rationale for screening potential liver transplant recipients from endemic areas follows.

Hepatopathy in complicated falciparum malaria: report from eastern India.

A prospective study done in 216 children with complicated falciparum malaria showed hepatopathy in 33.3% of cases with a higher incidence in children aged above five years. Bilirubin and alanine aminotransferase were moderately raised in most cases. No significant association with other common complications and no higher risk of mortality was observed.

Production of septal fibrosis of the liver by means of foreign protein injections into rats.

Similarities and differences in antigenic humoral responses and electrophoretic patterns between Capillaria hepatica and pig-serum were investigated as a contribution to the understanding of hepatic fibrosis induced by the parenteral administration of foreign proteins. Only two out of 10 rats receiving repeated intraperitoneal injections of an extract of Capillaria hepatica-infected mouse liver presented septal hepatic fibrosis (20%). Under the same experimental conditions, 4 out of 9 rats (44.4%) developed septal fibrosis following whole pig-serum administration. Injections of normal mouse liver extracts did not result in hepatic fibrosis. Since a 100% septal fibrosis rate is observed in experimentally Capillaria hepatica-infected rats, it appeared that Capillaria hepatica products continuously released from inside the liver creates a much more effective fibrosis inducing mechanism than the parenteral administration of such factors. Thus, repeated peritoneal administration of a foreign protein to rats would not reveal the full fibrogenic potential it may have under natural conditions.

Both interleukin-4 (IL-4) and IL-4 receptor alpha signaling contribute to the development of hepatic granulomas with optimal antileishmanial activity.

The roles of interleukin-4 (IL-4) and IL-13 in the regulation of immunity to Leishmania donovani infection are still poorly understood. Here we show that the increased parasite load observed in IL-4(-/-) and IL-4 receptor alpha(-/-) mice correlates with retarded granuloma maturation and antileishmanial activity and that the increased parasite load observed in IL-4 receptor alpha(-/-) mice correlates with increased NOS2 expression and decreased serum gamma interferon levels. IL-4 and IL-13 appear to play little role in regulating collagen deposition in L. donovani-induced granulomas.

Active hepatic capsulitis caused by Paragonimus westermani infection.

Paragonimiasis is an important re-emerging parasitosis in Japan. Although the lungs and pleural cavity are the principal sites affected with the parasite, ectopic infection can occur in unexpected sites such as skin and brain. This case report describes a patient with active hepatic capsulitis due to Paragonimus westermani infection. The patient was successfully treated with praziquantel at the dose of 75 mg/kg/day for 3 days.

Visceral larva migrans due to Ascaris suum which presented with eosinophilic pneumonia and multiple intra-hepatic lesions with severe eosinophil infiltration--outbreak in a Japanese area other than Kyushu.

A 32-year-old man presented with the chief complaint of severe cough. Examination of peripheral blood showed a marked increase in eosinophils. Chest CT demonstrated multiple ground glass opacities in both lungs. Bronchoalveolar lavage showed abundant eosinophils. Abdominal CT demonstrated multiple low attenuation areas in the liver. Liver biopsy with ultrasonography revealed severe eosinophil infiltrations around the portal veins. Serologically, a multi-dot enzyme linked immunosorbent assay (DOT-ELISA) and ELISA inhibition test using microtiter plates were positive for Ascaris suum. Thus, visceral larva migrans due to Ascaris suum was diagnosed. Outbreaks of this disease in Japan have previously been confined to the Kyushu area. The present case which occurred outside that area, illustrates the importance of constant attention to the epidemiology of this disease.

Pathogenesis of hepatic septal fibrosis associated with Capillaria hepatica infection of rats

A fibrose septal é uma forma comum de fibrose hepática, mas a sua etiologia e patogenia são ainda desconhecidas. Os ratos infectados com o verme Capillaria hepatica representam um bom modelo experimental para tal fibrose. Para verificar a contribuição de cada fator parasitário na patogenia, os seguintes experimentos foram realizados em ratos: a) para testar o papel dos ovos, estes foram isolados e injetados seja na cavidade peritoneal ou no interior do parênquima hepático; b) para verificar o papel dos vermes, foram tratados com mebendazol, ratos infectados aos 15 dias da inoculação; c) para o papel de ovos e vermes conjuntamente, os ratos com infecção de 30 dias foram tratados com mebendazol ou ivermectina. Os ovos injetados no fígado causaram fibrose focal, mas não fibrose septal; os vermes mortos antes da oviposição deram lugar apenas a discreta fibrose septal perifocal. Somente os animais tratados no 30o dia da infecção, com ovos e vermes em desintegração, mostraram fibrose septal sistematizada, tal como a vista nos controles da infecção. Assim, as pesquisas visando isolar o(s) fator(es) fibrogênico(s) devem considerar particularmente as lesões focais induzidas por vermes em desintegração e ovos imaturos