Ming-Ling Chang

Hepatitis B flares in chronic hepatitis B: Pathogenesis, natural course, and management

Hepatitis B flare, defined as an event with abrupt rise of alanine aminotransferase (ALT) levels to >5 times the upper limit of normal during chronic hepatitis B virus (HBV) infection, is considered to be the result of a human leukocyte antigen-I restricted, cytotoxic T lymphocyte mediated immune response against HBV and its downstream mechanisms. It may occur spontaneously, during or after antiviral therapy and in the setting of immunosuppression and/or chemotherapy. The clinical spectrum of hepatitis B flares varies from asymptomatic to symptomatic and typical overt acute hepatitis, even with hepatic decompensation or failure. Flares may also occur in viraemic patients with cirrhosis with higher incidence of decompensation/mortality, hence requiring immediate antiviral therapy. An upsurge of serum HBV DNA and hepatitis B surface antigen levels usually precedes the abrupt rise of ALT levels. Rising or stable and high HBV DNA during flares represent ineffective immune clearance and further hepatocytolysis, even hepatic decompensation, may occur. Such patients require immediate antiviral therapy. In contrast, bridging hepatic necrosis and/or alpha-fetoprotein levels >100 ng/ml or decreasing HBV DNA during flares represent a more effective immune clearance and frequently leads to seroclearance of HBV DNA and/or hepatitis B e antigen with remission. If patients are non-cirrhotic and there is no concern of developing decompensation, patients may be observed for 3-6 months before deciding on the need of antiviral therapy. Severe and repeated flares are prone to develop into decompensation or lead to the development of cirrhosis, thus a timely treatment to prevent the hepatitis B flare is better than to cope with the flare. Screening, monitoring and prophylactic or pre-emptive antiviral therapy is mandatory for patients who are going to receive immunosuppressants or chemotherapy.

Altered expression patterns of lipid metabolism genes in an animal model of HCV core-related, nonobese, modest hepatic steatosis

BackgroundBecause the gene expression patterns of nonobese hepatic steatosis in affected patients remain unclear, we sought to explore these patterns using an animal model of nonobese hepatic steatosis.MethodsWe developed mice that conditionally express the hepatitis C virus (HCV) core protein regulated by the tetracycline transactivator (tTA). Microarray analyses and reverse-transcription polymerase chain reaction were performed using liver samples of both the double transgenic mice (DTM), which express both the HCV core and tTA, and single transgenic mice (STM), which express tTA alone, at 2 months of age. Functional categories of genes with altered expression were classified using gene ontology programs. Serum glucose, lipid levels, and systemic blood pressure were also measured.ResultsApproximately 20–30% of hepatocytes from the DTM were steatotic. No significant differences were observed in the serum glucose, lipid content, or blood pressure levels between the DTM and STM. Gene expression analyses revealed Sterol-regulatory element-binding protein (SREBP) pathway activation and dysregulation of the following genes involved in lipid metabolism: 3-hydroxy-3-methylglutaryl-coenzyme A synthase 1, Apolipoprotein AII, Apolipoprotein CI, acyl-CoA thioesterase I, and fatty acid binding protein 1; in mitochondrial function: solute carrier family 25 member 25 and cytochrome c oxidase subunit II; in immune reaction: complement component 3, lymphocyte antigen 6 complex, locus A, lymphocyte antigen 6 complex, locus C, lymphocyte antigen 6 complex, locus D, and lymphocyte antigen 6 complex, locus E.ConclusionSome genes of lipid metabolism, mitochondrial function, and immune reaction and the SREBP pathway are involved in HCV core-related, nonobese, modest hepatic steatosis.

Hepatic inflammation mediated by hepatitis C virus core protein is ameliorated by blocking complement activation

BackgroundThe pathogenesis of inflammation and fibrosis in chronic hepatitis C virus (HCV) infection remains unclear. Transgenic mice with constitutive HCV core over-expression display steatosis only. While the reasons for this are unclear, it may be important that core protein production in these models begins during gestation, in contrast to human hepatitis C virus infection, which occurs post-natally and typically in adults. AIMS: To more realistically model the effect of core protein production in the adult liver, we developed a mouse with conditional expression of HCV core and examined the effect of core protein production in the adult liver.MethodsLiver biopsy samples from transgenic mice with tetracycline(tet)-regulated conditional core protein expression were evaluated immunohistologically. Microarray analysis of HCV core transgenic mice with steatohepatitis pointed to a role of the complement pathway. This was further explored by blocking complement activation by in vivo administration of CD55 (decay accelerating factor for complement), which inhibits activation of C3.ResultsTransgenic mice exhibited low, intermediate, or high HCV core protein expression when fed a permissive diet of standard chow. Aside from hepatic steatosis, hepatic inflammation and fibrosis were seen in mice with intermediate levels of core protein. Microarray analyses of inflamed liver demonstrated activation of both the complement (C3 up-regulation) and coagulation pathways (fibrinogen B up-regulation). Administration of CD55 reduced hepatic inflammation.ConclusionTransgenic mice that conditionally express intermediate HCV core protein develop inflammation, steatosis, and fibrosis. These effects mediated by HCV core are reduced by administration of CD55, a regulator of the complement pathway. The model may be valuable in investigating the pathogenesis of liver inflammation in chronic hepatitis C.

Clinical Events After Cessation of Lamivudine Therapy in Patients Recovered From Hepatitis B Flare With Hepatic Decompensation

BACKGROUND & AIMS Before guidelines were issued, many patients with hepatitis B flare and hepatic decompensation had discontinued lamivudine therapy instead of indefinite therapy. We investigated their outcomes. METHODS We performed a retrospective cohort study of 263 consecutive patients with chronic hepatitis B (94 with cirrhosis) who recovered from a flare of hepatitis with hepatic decompensation and were followed after cessation of lamivudine therapy. Clinical events that occurred during the follow-up period were assessed by chart review and analysis of results from retrospective assays. RESULTS The mean duration of lamivudine therapy was 12.1 ± 8.6 months; data were collected from patients for 89.1 ± 38.7 months after therapy ended. In the first year off therapy, 29.9% of patients had clinical relapse, 16.2% had hepatitis flares, and 8.2% had hepatic decompensation. There was no significant difference in the incidence of hepatic decompensation between patients with and without cirrhosis. Hepatocellular carcinoma developed in 14 patients 20-109 months after cessation of therapy, with 5-year cumulative incidence of 5.2% in patients with cirrhosis. Three patients with cirrhosis died of hepatic decompensation 38-76 months after cessation of therapy (5-year cumulative mortality, 2.9%). Multivariate analyses showed that men were more likely than women to have recurrence of hepatic decompensation (hazard ratio [HR], 4.339; P = .014). Liver cirrhosis (HR, 2.766; P = .041) and age (HR, 1.054; P = .023) increased risk for hepatocellular carcinoma. CONCLUSIONS Cessation of lamivudine therapy after recovery from hepatitis B flare with decompensation was safe for most patients. However, 8.2% develop decompensation within 1 year and can be rescued by timely retreatment. With close monitoring, the stopping strategy could be a feasible alternative to indefinite therapy, especially in low resource settings.

Regulation of fibronectin splicing in sinusoidal endothelial cells from normal or injured liver

Fn containing an extra type III domain (EIIIA in the rat, ED1 or EDA in humans) is commonly termed “fetal” fibronectin, but it is prominent during the injury response of adult tissues and mediates important early events in the response. This form is particularly apparent in acute liver injury, where it has been shown that sinusoidal endothelial cells produce EIIIA-fibronectin. This fibronectin isoform arises by alternative splicing of the primary transcript. In the present experiments, we have studied the regulation of fibronectin splicing in primary sinusoidal endothelial cells by transfecting a minigene containing the EIIIA exon and its flanking introns, driven by various promoters. The results indicate that fibronectin splicing in endothelial cells from normal liver is in part promoter-dependent. However, in cells from injured liver in which expression of both total and EIIIA-fibronectin is strikingly increased, promoter effects disappear. Because fibronectin splicing is known to be regulated in part by TGFβ, we also examined the effect of a soluble inhibitor of the TGFβ type 2 receptor. This agent had no effect on splicing by normal endothelial cells. By contrast, for endothelial cells from the injured liver, the splicing pattern reverted to that of normal cells, i.e., it became promoter-dependent. We conclude that, in the setting of injury in vivo, TGFβ overrides the promoter dependence of fibronectin splicing in normal cells. The data suggest that TGFβ modifies the spliceosome, if not through its known signaling intermediates, then through the products of genes regulated by this cytokine.

Identification of a novel pre-S2 mutation in a subgroup of chronic carriers with spontaneous clearance of hepatitis B virus surface antigen

Background and Aim:  The aim of the present study was to investigate whether spontaneous seroclearance of hepatitis B surface antigen (HBsAg) in patients with chronic hepatitis B could be attributed to the presence of pre‐S/S gene mutations.

α-Fetoprotein level-dependent early hepatitis B surface antigen decline during entecavir therapy in chronic hepatitis B with hepatitis flare

OBJECTIVES Hepatitis B surface antigen (HBsAg) reduction during nucleos(t)ide analogue therapy is related to ALT level. ALT reflects hepatocytolysis while α-fetoprotein (AFP) ≥100 ng/mL during hepatitis flare reflects more extensive hepatocytolysis (bridging hepatic necrosis). The impact of AFP levels on early HBsAg kinetics during entecavir therapy was investigated. METHODS HBsAg level was measured at baseline and months 6 and 12 of entecavir therapy in 149 chronic hepatitis B patients with hepatitis flare, defined as ALT ≥5× upper limit of normal (ULN), and 58 patients with ALT <5× ULN. RESULTS There was a significantly greater HBsAg reduction in an ALT (<5, 5-10, 10-20 and ≥20× ULN, P = 0.001) and AFP (<20, 20-99 and ≥100 ng/mL, P = 0.000) level-dependent manner. In hepatitis flares with a peak AFP level ≥20 ng/mL, the differences in HBsAg reduction across all ALT levels became non-significant. HBsAg reduction was greater in genotype B- than genotype C-infected patients with baseline ALT ≥20× ULN, but the difference became non-significant in those with peak AFP ≥100 ng/mL. Multivariate linear regression analysis showed that AFP level ≥100 ng/mL, baseline HBsAg level and genotype B were independent significant factors for greater HBsAg decline at month 6 of entecavir therapy. CONCLUSIONS During entecavir therapy, early HBsAg reduction increased in an AFP and ALT level-dependent manner, suggesting the impact of hepatocytolysis rather than nucleos(t)ide analogue per se. Notably, a higher AFP level during hepatitis flare, reflecting more extensive hepatic necrosis, was a more powerful factor than ALT and genotype for greater HBsAg decline.

The evolving relationship between adiponectin and insulin sensitivity in hepatitis C patients during viral clearance

ABSTRACT Background: The evolution of the relationship between adiponectin and insulin sensitivity in hepatitis C virus (HCV) patients during viral clearance is unclear and warrants investigation. Methods: A prospective study including 747 consecutive chronic hepatitis C (CHC) patients, of whom 546 had completed a course of anti-HCV therapy and underwent pre-, peri- and post-therapy surveys for anthropomorphic, viral, metabolic and hepatic profiles and adiponectin levels, was conducted in a tertiary care center. Results: Multivariate analyses indicated associations of sex, triglyceride levels and hepatic steatosis with adiponectin levels and of triglyceride levels and interferon λ3 (IFNL3) genotype with homeostasis model assessment-estimated insulin resistance (HOMA-IR) levels before anti-HCV therapy. In patients with a sustained virological response (SVR; n = 455), at 24 weeks post-therapy, sex, BMI, aspartate aminotransferase to platelet ratio index (APRI), HOMA-IR and steatosis were associated with adiponectin levels, and IFNL3 genotype was associated with HOMA-IR levels. GEE analysis demonstrated that SVR affected longitudinal trends in adiponectin levels. Compared with pre-therapy levels, adiponectin and APRI levels decreased 24 weeks post-therapy in SVR patients, regardless of baseline insulin resistance (IR). However, HOMA-IR levels decreased in SVR patients with baseline IR but increased in those without baseline IR. Compared with controls, immunohistochemical studies showed that pre-therapy CHC patients had higher hepatic adiponectin expression associated with hepatic fibrosis. Conclusions: During HCV infection, adiponectin may affect insulin sensitivity through triglycerides. After viral clearance, adiponectin levels were directly associated with insulin sensitivity and decreased upon improved hepatic fibrosis; with a link to the IFNL3 genotype, insulin sensitivity improved only in patients with baseline IR.

Overt acute hepatitis B is more severe in female patients

It has been recognized that female patients show a more robust immune response to viral infection and, hence, may enhance virus clearance but also contribute to increased tissue damage and disease symptoms. Along this line, women are more likely to clear the hepatitis C virus infection spontaneously. However, male patients with acute hepatitis A had a higher case fatality rate with an age adjusted odds ratio of 2.35 in a recent Taiwan study of 3,990 hospitalized patients. There seems no data on the sex difference in the severity of acute hepatitis B virus (HBV) infection.

Durability of Telbivudine-Associated Improvement of Renal Function Following Withdrawal or Switching of Antivirals in Chronic Hepatitis B Patients

Abstract Background Besides antiviral activities against hepatitis B virus (HBV), telbivudine has an extrahepatic pharmaceutical effect: to improve renal function assessed by estimated glomerular filtration rate (eGFR). However, the durability of this effect after withdrawal of telbivudine or switching to other antivirals has never been investigated. Methods We conducted a postmarketing, real-world observation study for telbivudine treatment. The durability of telbivudine-associated renal function improvement was examined following withdrawal/switching of antivirals. Results Of 160 telbivudine-treated, chronic hepatitis B patients, 21, 6, and 2 patients were loss to follow-up, dead, and pregnant during the study, respectively. Of the remaining 131 patients, 26, 47, 28, and 30 patients experienced telbivudine withdrawal, continuous use of telbivudine, switching to entecavir, or switching to tenofovir, respectively. During the first 2 years, eGFR in telbivudine-treated patients significantly improved before withdrawal/switching of antivirals (P = .009). Thereafter, eGFR remained unchanged for >1 year in the withdrawal (P = .100) and continuous use (P = .517) subgroups, but decreased significantly in the switching to entecavir (P = .002) and switching to tenofovir (P < .001) subgroups. Multivariate logistic regression analysis revealed that switching to tenofovir and poor liver functional reserve were predictors for eGFR deterioration. Conclusions Telbivudine-associated renal function improvement was durable after withdrawal or continuous use of telbivudine. However, renal function deteriorated if patients were switched to entecavir or tenofovir.