The ZCCHC14/TENT4 complex is required for hepatitis A virus RNA synthesis.

Despite excellent vaccines, resurgent outbreaks of hepatitis A have caused thousands of hospitalizations and hundreds of deaths within the United States in recent years. There is no effective antiviral therapy for hepatitis A, and many aspects of the hepatitis A virus (HAV) replication cycle remain to be elucidated. Replication requires the zinc finger protein ZCCHC14 and noncanonical TENT4 poly(A) polymerases with which it associates, but the underlying mechanism is unknown. Here, we show that ZCCHC14 and TENT4A/B are required for viral RNA synthesis following translation of the viral genome in infected cells. Cross-linking immunoprecipitation sequencing (CLIP-seq) experiments revealed that ZCCHC14 binds a small stem-loop in the HAV 5' untranslated RNA possessing a Smaug recognition-like pentaloop to which it recruits TENT4. TENT4 polymerases lengthen and stabilize the 3' poly(A) tails of some cellular and viral mRNAs, but the chemical inhibition of TENT4A/B with the dihydroquinolizinone RG7834 had no impact on the length of the HAV 3' poly(A) tail, stability of HAV RNA, or cap-independent translation of the viral genome. By contrast, RG7834 inhibited the incorporation of 5-ethynyl uridine into nascent HAV RNA, indicating that TENT4A/B function in viral RNA synthesis. Consistent with potent in vitro antiviral activity against HAV (IC50 6.11 nM), orally administered RG7834 completely blocked HAV infection in Ifnar1-/- mice, and sharply reduced serum alanine aminotransferase activities, hepatocyte apoptosis, and intrahepatic inflammatory cell infiltrates in mice with acute hepatitis A. These results reveal requirements for ZCCHC14-TENT4A/B in hepatovirus RNA synthesis, and suggest that TENT4A/B inhibitors may be useful for preventing or treating hepatitis A in humans.

Amantadine and Rimantadine Inhibit Hepatitis A Virus Replication through the Induction of Autophagy.

Hepatitis A virus (HAV) infection is a major cause of acute viral hepatitis worldwide. Furthermore, HAV causes acute liver failure or acute-on-chronic liver failure. However, no potent anti-HAV drugs are currently available in the clinical situations. There have been some reports that amantadine, a broad-spectrum antiviral, suppresses HAV replication in vitro. Therefore, we examined the effects of amantadine and rimantadine, derivates of adamantane, on HAV replication, and investigated the mechanisms of these drugs. In the present study, we evaluated the effects of amantadine and rimantadine on HAV HM175 genotype IB subgenomic replicon replication and HAV HA11-1299 genotype IIIA replication in cell culture infection systems. Amantadine and rimantadine significantly inhibited HAV replication at the post-entry stage in Huh7 cells. HAV infection inhibited autophagy by suppressing the autophagy marker light chain 3 and reducing number of lysosomes. Proteomic analysis on HAV-infected Huh7 cells treated by amantadine and rimantadine revealed the changes of the expression levels in 42 of 373 immune response-related proteins. Amantadine and rimantadine inhibited HAV replication, partially through the enhancement of autophagy. Taken together, our results suggest a novel mechanism by which HAV replicates along with the inhibition of autophagy and that amantadine and rimantadine inhibit HAV replication by enhancing autophagy. IMPORTANCE Amantadine, a nonspecific antiviral medication, also effectively inhibits HAV replication. Autophagy is an important cellular mechanism in several virus-host cell interactions. The results of this study provide evidence indicating that autophagy is involved in HAV replication and plays a role in the HAV life cycle. In addition, amantadine and its derivative rimantadine suppress HAV replication partly by enhancing autophagy at the post-entry phase of HAV infection in human hepatocytes. Amantadine may be useful for the control of acute HAV infection by inhibiting cellular autophagy pathways during HAV infection processes.

Masitinib Inhibits Hepatitis A Virus Replication.

The hepatitis A virus (HAV) infection causes acute hepatitis. HAV also induces acute liver failure or acute-on-chronic liver failure; however, no potent anti-HAV drugs are currently available in clinical situations. For anti-HAV drug screening, more convenient and useful models that mimic HAV replication are needed. In the present study, we established HuhT7-HAV/Luc cells, which are HuhT7 cells stably expressing the HAV HM175-18f genotype IB subgenomic replicon RNA harboring the firefly luciferase gene. This system was made by using a PiggyBac-based gene transfer system that introduces nonviral transposon DNA into mammalian cells. Then, we investigated whether 1134 US Food and Drug Administration (FDA)-approved drugs exhibited in vitro anti-HAV activity. We further demonstrated that treatment with tyrosine kinase inhibitor masitinib significantly reduced both HAV HM175-18f genotype IB replication and HAV HA11-1299 genotype IIIA replication. Masitinib also significantly inhibited HAV HM175 internal ribosomal entry-site (IRES) activity. In conclusion, HuhT7-HAV/Luc cells are adequate for anti-HAV drug screening, and masitinib may be useful for the treatment of severe HAV infection.

Iminosugar Glucosidase Inhibitors Reduce Hepatic Inflammation in Hepatitis A Virus-Infected Ifnar1-/- Mice.

Iminosugar compounds are monosaccharide mimetics with broad but generally weak antiviral activities related to inhibition of enzymes involved in glycobiology. Miglustat (N-butyl-1-deoxynojirimycin), which is approved for the treatment of lipid storage diseases in humans, and UV-4 [N-(9-methoxynonyl)-1-deoxynojirimycin] inhibit the replication of hepatitis A virus (HAV) in cell culture (50% inhibitory concentrations [IC50s] of 32.13 µM and 8.05 µM, respectively) by blocking the synthesis of gangliosides essential for HAV cell entry. We used a murine model of hepatitis A and targeted mass spectrometry to assess the capacity of these compounds to deplete hepatic gangliosides and modify the course of HAV infection in vivo. Miglustat, given by gavage to Ifnar1-/- mice (4,800 mg/kg of body weight/day) depleted hepatic gangliosides by 69 to 75% but caused substantial gastrointestinal toxicity and failed to prevent viral infection. UV-4, similarly administered in high doses (400 mg/kg/day), was well tolerated but depleted hepatic gangliosides by only 20% after 14 days. UV-4 depletion of gangliosides varied by class. Several GM2 species were paradoxically increased, likely due to inhibition of ß-glucosidases that degrade gangliosides. Both compounds enhanced, rather than reduced, virus replication. Nonetheless, both iminosugars had surprising anti-inflammatory effects, blocking the accumulation of inflammatory cells within the liver. UV-4 treatment also resulted in a decrease in serum alanine aminotransferase (ALT) elevations associated with acute hepatitis A. These anti-inflammatory effects may result from iminosugar inhibition of cellular α-glucosidases, leading to impaired maturation of glycan moieties of chemokine and cytokine receptors, and point to the potential importance of paracrine signaling in the pathogenesis of acute hepatitis A. IMPORTANCE Hepatitis A virus (HAV) is a common cause of viral hepatitis. Iminosugar compounds block its replication in cultured cells by inhibiting the synthesis of gangliosides required for HAV cell entry but have not been tested for their ability to prevent or treat hepatitis A in vivo. We show that high doses of the iminosugars miglustat and UV-4 fail to deplete gangliosides sufficiently to block HAV infection in mice lacking a key interferon receptor. These compounds nonetheless have striking anti-inflammatory effects on the HAV-infected liver, reducing the severity of hepatitis despite enhancing chemokine and cytokine expression resulting from hepatocyte-intrinsic antiviral responses. We propose that iminosugar inhibition of cellular α-glucosidases impairs the maturation of glycan moieties of chemokine and cytokine receptors required for effective signaling. These data highlight the potential importance of paracrine signaling pathways in the inflammatory response to HAV and add to our understanding of HAV pathogenesis in mice.

Treatment and prevention of viral hepatitis in pregnancy.

Viral hepatitis in pregnancy may be caused by many types of viruses that cause systemic infection or target hepatocytes in their pathogenesis. Because viral hepatitis during pregnancy may represent acute or chronic infection or the reactivation of a prior infection, a high clinical suspicion, medical history review, and awareness of risk factors for the acquisition of infection are important management principles. The route of infection varies widely and ranges from fecal-oral transmission for the hepatitis A and E viruses to vertical transmission for hepatitis B, blood-borne transmission for hepatitis C, and sexual transmission for the herpes simplex virus. For this reason, the exposure details about travel, food preferences, drug use, and sexual contacts are important to elicit. Although routine prenatal screening is recommended for chronic viral hepatitis caused by hepatitis B and C, most other causes of viral hepatitis in pregnancy are detected in the setting of compatible signs and symptoms (fatigue, abdominal discomfort, jaundice, scleral icterus) or incidentally noted transaminitis on routine labs. Serologic testing is helpful for diagnosis with molecular testing as indicated to guide the management of hepatitis B and C. Preventive vaccines for hepatitis A and B with established safety of use in pregnancy are recommended for women who are at risk of acquisition. Postexposure prophylaxis for hepatitis A is a single dose of immunoglobulin and vaccination can be used if immunoglobulin G is not available. Antiviral therapy with tenofovir disoproxil fumarate is recommended as prophylaxis in pregnant women with active hepatitis B and an elevated viral load (>200,000 IU/mL) during the third trimester to prevent vertical transmission. The neonate exposed to hepatitis B at birth should receive immunoglobulin G and a monovalent birth dose vaccine within 12 hours, followed by completion of the 3-dosage vaccine series. The prevalence of hepatitis C in women of reproductive age has increased in the United States, and the role of antiviral therapy during pregnancy is of great interest. Cesarean delivery is not currently recommended for the sole purpose of reducing vertical transmission risk in pregnant women with viral hepatitis. Breastfeeding is recommended in women with hepatitis A, B, and C. New and promising prevention and treatment options for hepatitis B and C are under investigation. Investigators and regulatory authorities should ensure that these clinical trials for promising antivirals and vaccines are designed to include pregnant and lactating women.

Evaluation of Potential Anti-Hepatitis A Virus 3C Protease Inhibitors Using Molecular Docking.

Hepatitis A virus (HAV) infection is a major cause of acute hepatitis worldwide and occasionally causes acute liver failure and can lead to death in the absence of liver transplantation. Although HAV vaccination is available, the prevalence of HAV vaccination is not adequate in some countries. Additionally, the improvements in public health reduced our immunity to HAV infection. These situations motivated us to develop potentially new anti-HAV therapeutic options. We carried out the in silico screening of anti-HAV compounds targeting the 3C protease enzyme using the Schrodinger Modeling software from the antiviral library of 25,000 compounds to evaluate anti-HAV 3C protease inhibitors. Additionally, in vitro studies were introduced to examine the inhibitory effects of HAV subgenomic replicon replication and HAV HA11-1299 genotype IIIA replication in hepatoma cell lines using luciferase assays and real-time RT-PCR. In silico studies enabled us to identify five lead candidates with optimal binding interactions in the active site of the target HAV 3C protease using the Schrodinger Glide program. In vitro studies substantiated our hypothesis from in silico findings. One of our lead compounds, Z10325150, showed 47% inhibitory effects on HAV genotype IB subgenomic replicon replication and 36% inhibitory effects on HAV genotype IIIA HA11-1299 replication in human hepatoma cell lines, with no cytotoxic effects at concentrations of 100 µg/mL. The effects of the combination therapy of Z10325150 and RNA-dependent RNA polymerase inhibitor, favipiravir on HAV genotype IB HM175 subgenomic replicon replication and HAV genotype IIIA HA11-1299 replication showed 64% and 48% inhibitory effects of HAV subgenomic replicon and HAV replication, respectively. We identified the HAV 3C protease inhibitor Z10325150 through in silico screening and confirmed the HAV replication inhibitory activity in human hepatocytes. Z10325150 may offer the potential for a useful HAV inhibitor in severe hepatitis A.

T cells protect against hepatitis A virus infection and limit infection-induced liver injury.

BACKGROUND & AIMS: Hepatitis A virus (HAV) is a common cause of enterically transmitted viral hepatitis. In non-immune individuals, infection results in typically transient but occasionally fulminant and fatal inflammatory liver injury. Virus-specific T cell frequencies peak when liver damage is at its zenith, leading to the prevalent notion that T cells exacerbate liver disease, as suspected for other hepatotropic virus infections. However, the overall contribution of T cells to the control of HAV and the pathogenesis of hepatitis A is unclear and has been impeded by a historic lack of small animal models. METHODS: Ifnar1-/- mice are highly permissive for HAV and develop pathogenesis that recapitulates many features of hepatitis A. Using this model, we identified HAV-specific CD8+ and CD4+ T cells by epitope mapping, and then used tetramers and functional assays to quantify T cells in the liver at multiple times after infection. We assessed the relationships between HAV-specific T cell frequency, viral RNA amounts, and liver pathogenesis. RESULTS: A large population of virus-specific T cells accumulated within the livers of Ifnar1-/- mice during the first 1-2 weeks of infection and persisted over time. HAV replication was enhanced and liver disease exacerbated when mice were depleted of T cells. Conversely, immunization with a peptide vaccine increased virus-specific CD8+ T cell frequencies in the liver, reduced viral RNA abundance, and lessened liver injury. CONCLUSION: These data show that T cells protect against HAV-mediated liver injury and can be targeted to improve liver health. LAY SUMMARY: Hepatitis A virus is a leading cause of acute viral hepatitis worldwide. T cells were thought to contribute to liver injury during acute infection. We now show that virus-specific T cells protect against infection and limit liver injury.

Superinfection of hepatitis A virus in hepatocytes infected with hepatitis B virus.

Hepatitis A virus (HAV) infection is a major cause of acute hepatitis including acute liver failure. Hepatitis B infection (HBV) occurs worldwide, with the highest rates in Asian and African countries, and there are several reports that HAV infection may have a more severe clinical course in patients with chronic HBV infection. We previously demonstrated that Japanese miso extracts have inhibitory effects on HAV replication. In the present study, we examined the replication of HAV and HBV in a hepatocyte superinfection model and the inhibitory effects of Japanese miso extracts on both viruses. According to the results, HAV infection inhibited HBV replication in superinfected hepatocytes, and Japanese rice-koji miso extracts had inhibitory effects on HAV replication. Our findings provide useful information for clinicians in managing HAV infection in patients with chronic HBV infection.

Design of a supply chain distribution network for communicable diseases: Hepatitis A in Jordan as a case study.

PURPOSE: Distribution network plays a vital role on the efficiency and the responsiveness of a supply chain. Any product or service goes through a network until it reaches the final customer. Health care systems incorporate distribution networks to better provide health services to patients. In this study, a distribution network for communicable diseases has been developed. The proposed network addresses Hepatitis A in Jordan as a case study, as it is considered one of the common communicable diseases in Jordan. FINDINGS: A regression model was developed to predict future incidents of Hepatitis A in Jordan to build a distribution network based on the future required resources. An optimization clustering model was used to structure the appropriate distribution network. The proposed network was compared with the current network used for distribution of medications for Hepatitis A. CONCLUSION: The new network incurs less cost in delivering medications to the required hospitals as the traveling distance is less. As future work, it is recommended to incorporate more communicable diseases to develop more realistic distribution network.

Steroid therapy in children with fulminant hepatitis A.

Fulminant hepatic failure is a life-threatening disease. Hepatitis A virus (HAV) can cause fulminant hepatic failure and death in about 0.2% of cases. Extensive destruction of infected hepatocytes by immune-mediated lysis is thought to be the cause. We aimed to evaluate the use of steroid therapy in children with fulminant HAV. This study included 33 children with fulminant HAV in two groups. Steroid group: comprised of 18 children who received prednisolone (1 mg/kg/d) or its equivalent dose of methylprednisolone, and the nonsteroid group: comprised another 15 children who did not receive steroid therapy. Age and sex were matched for both groups (P > .05), and they were comparable regarding baseline clinical and laboratory characteristics. Of the steroid group, 15 patients survived and 3 died, while in the nonsteroid group, 4 patients survived and 11 died (P = .001). Of the living patients, 15 of 19 (78.9%) received steroids while only 3 of 14 (21.4%) of the dead patients received steroids (P = .001). Stepwise regression analysis showed that steroid therapy was the only independent variable associated with recovery (P = .001). Steroid therapy in children with fulminant HAV associated significantly with improved outcome and survival. Future studies on a larger population size are strongly recommended.

Examining Hepatitis, A and B Vaccination, and HBV Reactivation Monitoring During Direct-Acting Antiviral Therapy for Hepatitis C.

The objective of this study was to examine Hepatitis A (HAV) and Hepatitis B (HBV) screening, and the risk of HBV reactivation during Hepatitis C (HCV) therapy with direct-acting antivirals (DAAs). A retrospective chart review was performed of patients treated with second generation DAA therapy from January 2014 to September 2016 at the Iowa City VA Healthcare System. In total 409 patients initiated HCV treatment, 308 (75%) and 241 (59%) were HAV and HBV vaccine eligible, respectively. Among those, 24 (8%) received a HAV vaccine, while only 20 (8%) received a HBV vaccine. Of these, 7 patients initiating an immunization in the clinic had record of completing the series. Further, 101 patients had a reactive Hepatitis B core Antibody indicating previous HBV infection, and 3 of these were tested for HBV reactivation during HCV therapy. Overall, the assessment found low rates of HAV and HBV vaccine administration, indicating missed opportunities for preventative care during HCV therapy. With the known risk of HBV reactivation with DAAs, the need for HAV and HBV screening is essential.

Comparing the Clinical Features and Outcomes of Acute Hepatitis E Viral Infections with Those of Acute Hepatitis A, B, and C Infections in Korea.

OBJECTIVES: This study investigated the etiology of acute viral hepatitis and compared the clinical features of hepatitis E virus (HEV) infections with those of other acute viral hepatitis infections in Korea. METHODS: This study included 2,357 consecutive patients who were diagnosed with acute hepatitis, based on acute illness with jaundice or elevated alanine aminotransferase levels (>100 IU/L), between January 2007 and January 2016. Acute viral infections were observed in 23 (19.8%) patients with HEV, 49 (42.2%) patients with hepatitis A virus, 28 (24.1%) patients with hepatitis B virus, and 16 (13.8%) patients with hepatitis C virus. RESULTS: The incidence of acute HEV infection was higher among older patients (median age: 49 years) and male patients (69.6%), and was associated with the consumption of undercooked or uncooked meat (43.5%). Half of the acute HEV infections involved underlying liver disease, such as alcoholic liver disease, chronic hepatitis B, common bile duct stones, and autoimmune hepatitis. Two HEV-infected patients were diagnosed with Guillain-Barré syndrome, although no patients developed fulminant hepatitis. CONCLUSION: Our findings indicate that HEV infection in Korea is frequently transmitted through the consumption of raw meat and may cause acute or chronic liver disease.

Hepatitis A Cases Among Food Handlers: A Local Health Department Response-New York City, 2013.

During 2013, the New York City Department of Health and Mental Hygiene (DOHMH) received reports of 6 hepatitis A cases among food handlers. We describe our decision-making process for public notification, type of postexposure prophylaxis (PEP) offered, and lessons learned. For 3 cases, public notification was issued and DOHMH offered only hepatitis A vaccine as PEP. Subsequent outbreaks resulted from 1 case for which no public notification was issued or PEP offered, and 1 for which public notification was issued and PEP was offered too late. DOHMH continues to use environmental assessments to guide public notification decisions and offer only hepatitis A vaccine as PEP after public notification but recognizes the need to evaluate each situation individually. The PEP strategy employed by DOHMH should be considered because hepatitis A vaccine is immunogenic in all age groups, can be obtained by local jurisdictions more quickly, and is logistically easier to administer in mass clinics than immunoglobulin.

Novel perspectives for hepatitis A virus therapy revealed by comparative analysis of hepatitis C virus and hepatitis A virus RNA replication.

UNLABELLED: Hepatitis A virus (HAV) and hepatitis C virus (HCV) are two positive-strand RNA viruses sharing a similar biology, but causing opposing infection outcomes, with HAV always being cleared and HCV establishing persistence in the majority of infections. To gain deeper insight into determinants of replication, persistence, and treatment, we established a homogenous cell-culture model allowing a thorough comparison of RNA replication of both viruses. By screening different human liver-derived cell lines with subgenomic reporter replicons of HAV as well as of different HCV genotypes, we found that Huh7-Lunet cells supported HAV- and HCV-RNA replication with similar efficiency and limited interference between both replicases. HAV and HCV replicons were similarly sensitive to interferon (IFN), but differed in their ability to establish persistent replication in cell culture. In contrast to HCV, HAV replicated independently from microRNA-122 and phosphatidylinositol 4-kinase IIIα and ß (PI4KIII). Both viruses were efficiently inhibited by cyclosporin A and NIM811, a nonimmunosuppressive analog thereof, suggesting an overlapping dependency on cyclophilins for replication. However, analysis of a broader set of inhibitors revealed that, in contrast to HCV, HAV does not depend on cyclophilin A, but rather on adenosine-triphosphate-binding cassette transporters and FK506-binding proteins. Finally, silibinin, but not its modified intravenous formulation, efficiently inhibited HAV genome replication in vitro, suggesting oral silibinin as a potential therapeutic option for HAV infections. CONCLUSION: We established a cell-culture model enabling comparative studies on RNA replication of HAV and HCV in a homogenous cellular background with comparable replication efficiency. We thereby identified new host cell targets and potential treatment options for HAV and set the ground for future studies to unravel determinants of clearance and persistence.

[Q fever : A rare differential diagnosis of granulomatous disease]. / Q-Fieber : Eine seltene Differenzialdiagnose granulomatöser Erkrankungen.

Q fever is a worldwide distributed zoonotic disease with a mostly benign course, which regularly reoccurs in Germany. This report is about a patient with sporadic serologically proven Q fever, which also showed typical histopathological findings with nonspecific granulomatous hepatitis, usually seen in acute disease. The bone marrow biopsy revealed so-called doughnut granulomas, which are not pathognomonic but a typical finding in Q fever. This case report impressively underlines that the histomorphological findings can make a decisive contribution to the clarification by extended differential diagnostics, even though it plays a subordinate role in the routine diagnostics of disseminated Q fever.

Liver injury in acute hepatitis A is associated with decreased frequency of regulatory T cells caused by Fas-mediated apoptosis.

OBJECTIVE: Foxp3(+)CD4(+)CD25(+) regulatory T cells (Tregs) control immune responses, but their role in acute viral hepatitis remains elusive. Herein, we investigated alteration in the peripheral blood Treg population during acute hepatitis A (AHA) and its implication in the immune-mediated liver injury. DESIGN: The study included 71 patients with AHA, and peripheral blood mononuclear cells (PBMCs) were isolated. The suppressive activity of Treg population was determined by assessing anti-CD3/CD28-stimulated proliferation of Treg-depleted and reconstituted PBMCs. Treg cell frequency, phenotype and apoptosis in PBMCs were analysed by flow cytometry. RESULTS: The frequency of circulating Tregs was reduced during AHA. Moreover, the suppressive activity of the total Treg pool in the peripheral blood was attenuated during AHA. Treg frequency and suppressive activity of the Treg population inversely correlated with the serum alanine aminotransferase level. Fas was overexpressed on Tregs during AHA, suggesting their susceptibility to Fas-induced apoptosis. Indeed, increased apoptotic death was observed in Tregs of patients with AHA compared with healthy controls. In addition, agonistic anti-Fas treatment further increased apoptotic death of Tregs from patients with AHA. The decreased Treg frequency and Fas overexpression on Tregs were not observed in other acute liver diseases such as acute hepatitis B, acute hepatitis C and toxic/drug-induced hepatitis. CONCLUSIONS: The size of the Treg pool was contracted during AHA, resulting from apoptosis of Tregs induced by a Fas-mediated mechanism. Decrease in Treg numbers led to reduced suppressive activity of the Treg pool and consequently resulted in severe liver injury during AHA.

The JAK2 inhibitor AZD1480 inhibits hepatitis A virus replication in Huh7 cells.

The JAK2 inhibitor AZD1480 has been reported to inhibit La protein expression. We previously demonstrated that the inhibition of La expression could inhibit hepatitis A virus (HAV) internal ribosomal entry-site (IRES)-mediated translation and HAV replication in vitro. In this study, we analyzed the effects of AZD1480 on HAV IRES-mediated translation and replication. HAV IRES-mediated translation in COS7-HAV-IRES cells was inhibited by 0.1-1 µM AZD1480, a dosage that did not affect cell viability. Results showed a significant reduction in intracellular HAV HA11-1299 genotype IIIA RNA levels in Huh7 cells treated with AZD1480. Furthermore, AZD1480 inhibited the expression of phosphorylated-(Tyr-705)-signal transducer and activator of transcription 3 (STAT3) and La in Huh7 cells. Therefore, we propose that AZD1480 can inhibit HAV IRES activity and HAV replication through the inhibition of the La protein.

Clinacanthus nutans (Burm. f.) Lindau Ethanol Extract Inhibits Hepatoma in Mice through Upregulation of the Immune Response.

Clinacanthans nutans (Burm. f.) Lindau is a popular medicinal vegetable in Southern Asia, and its extracts have displayed significant anti-proliferative effects on cancer cells in vitro. However, the underlying mechanism for this effect has yet to be established. This study investigated the antitumor and immunomodulatory activity of C. nutans (Burm. f.) Lindau 30% ethanol extract (CN30) in vivo. CN30 was prepared and its main components were identified using high-performance liquid chromatography (HPLC) and mass spectrometry (LC/MS/MS). CN30 had a significant inhibitory effect on tumor volume and weight. Hematoxylin and eosin (H & E) staining and TUNEL assay revealed that hepatoma cells underwent significant apoptosis with CN30 treatment, while expression levels of proliferation markers PCNA and p-AKT were significantly decreased when treated with low or high doses of CN30 treatment. Western blot analysis of PAPR, caspase-3, BAX, and Bcl2 also showed that CN30 induced apoptosis in hepatoma cells. Furthermore, intracellular staining analysis showed that CN30 treatment increased the number of IFN-γ⁺ T cells and decreased the number of IL-4⁺ T cells. Serum IFN-γ and interleukin-2 levels also significantly improved. Our findings indicated that CN30 demonstrated antitumor properties by up-regulating the immune response, and warrants further evaluation as a potential therapeutic agent for the treatment and prevention of cancers.

Molecular biology and inhibitors of hepatitis A virus.

Hepatitis A virus (HAV) is a faeco-orally transmitted picornavirus and is one of the main causes of acute hepatitis worldwide. An overview of the molecular biology of HAV is presented with an emphasis on recent findings. Immune evasion strategies and a possible correlation between HAV and atopy are discussed as well. Despite the availability of efficient vaccines, antiviral drugs targeting HAV are required to treat severe cases of fulminant hepatitis, contain outbreaks, and halt the potential spread of vaccine-escape variants. Additionally, such drugs could be used to shorten the period of illness and decrease associated economical costs. Several known inhibitors of HAV with various mechanisms of action will be discussed. Since none of these molecules is readily useable in the clinic and since the availability of an anti-HAV drug would be of clinical importance, increased efforts should be targeted toward discovery and development of such antivirals.