Hepatitis B virus (HBV) core antigen-specific regulatory T cells confer sustained remission to anti-HBV therapy in chronic hepatitis B with acute exacerbation

Spontaneous Flares of Chronic Hepatitis B Virus in Hepatitis Be Antigen Negative Carriers Who Subsequently Clear Hepatitis B Surface Antigen

BACKGROUND

Acute exacerbations of chronic hepatitis B virus (HBV) infections can occur in HBV-infected, hepatitis e antigen (HBeAg)-negative patients in the absence of recent withdrawal of antiviral or immunosuppressive therapies. Whether these spontaneous "flares" predict subsequent loss of hepatitis B surface antigen (HBsAg) has yet to be determined.

OBJECTIVES

To document the percent of patients who experience spontaneous HBV flares and severity of the flares in chronic HBeAg-negative carriers.

METHODS

A retrospective review of an HBV database identified and followed HBeAg-negative patients for biochemical evidence of flares (ALT > 5× normal) and subsequent HBsAg status. Patients that subsequently cleared HBsAg were matched 1:1 with those who remained HBsAg positive.

RESULTS

Of 1299 HBeAg-negative patients followed for 10.2 ± 6.1 years, 88 (6.8%) developed spontaneous HBV flares. Flares occurred in 14/115 (12.2%) patients who subsequently cleared HBsAg and 4/111 (3.6%) matched patients who remained HBsAg positive (p = 0.025). The severity of flares was similar in the two study cohorts. Following multivariate analyses, only low HBV-DNA levels at baseline identified patients likely to subsequently clear HBsAg.

CONCLUSIONS

Although more common in patients who subsequently clear HBsAg, spontaneous HBV flares do not predict subsequent HBsAg clearance.

Chemiluminescent Optical Fiber Immunosensor Combining Surface Modification and Signal Amplification for Ultrasensitive Determination of Hepatitis B Antigen

Optical fiber based immunosensors are very attractive for biomarker detection. In order to improve the sensor response, we propose a promising strategy which combines porous-layer modification of the fiber surface and streptavidin-biotin-peroxidase nano-complex signal amplification in chemiluminescent detection. Two hepatitis B antigens, hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg), are used as the targets for analysis using the proposed sensor. Comparing to immunoassays using normal optical fiber sensors, the response of the present sensor is enhanced by a factor of 4.8 and 6.7 for detection of HBsAg and HBeAg, respectively. The limit-of-quantitation of the proposed method is as low as 0.3 fg/mL (0.01 fg/mL) with a wide linear response range of 3 fg/mL–150 ng/mL (0.1 fg/mL–160 ng/mL) for sensing HBsAg (HBeAg). Quantitative determination of HBsAg and HBeAg in human serum samples is performed, showing the applicability of the proposed method for biomarker detection.

INASL Guidelines on Management of Hepatitis B Virus Infection in Patients receiving Chemotherapy, Biologicals, Immunosupressants, or Corticosteroids

Hepatitis B Virus (HBV) reactivation in patients receiving chemotherapy, biologicals, immunosupressants, or corticosteroids is emerging to be an important cause of morbidity and mortality in patients with current or prior exposure to HBV infection. These patients suffer a dual onslaught of illness: one from the primary disease for which they are receiving the culprit drug that led to HBV reactivation, and the other from HBV reactivation itself. The HBV reactivation not only leads to a compromised liver function, which may culminate into hepatic failure; it also adversely impacts the treatment outcome of the primary illness. Hence, identification of patients at risk of reactivation before starting these drugs, and starting treatment aimed at prevention of HBV reactivation is the best strategy of managing these patients. There are no Indian guidelines on management of HBV infection in patients receiving chemotherapy, biologicals, immunosupressants, or corticosteroids for the treatment of rheumatologic conditions, malignancies, inflammatory bowel disease, dermatologic conditions, or solid-organ or bone marrow transplantation. The Indian National Association for Study of the Liver (INASL) had set up a taskforce on HBV in 2016, with a mandate to develop consensus guidelines for management of various aspects of HBV infection, relevant to India. In 2017 the taskforce had published the first INASL guidelines on management of HBV infection in India. In the present guidelines, which are in continuation with the previous guidelines, the issues on management of HBV infection in patients receiving chemotherapy, biologicals, immunosupressants, or corticosteroids are addressed.

The prevalence and risk factors of hepatitis B flares in chronic hepatitis B patients receiving glucocorticoid pulse therapy

Background The frequency and risks of hepatitis B reactivation in patients receiving glucocorticoid pulse therapy has not been reported. Objective The aim of our study was to investigate the possibility of glucocorticoid pulse therapy related hepatitis B flare. Setting A Taiwanese tertiary hospital. Methods Chronic hepatitis B patients underwent glucocorticoid pulse therapy were retrospectively collected. The prevalence of hepatitis B flare was counted, and the statistic analysis with logistic regression was adapted to assess the associated risk factors. Main outcome measure The prevalence and associated risk factors of the individuals with hepatitis B flare after glucocorticoid pulse therapy were collected and analyzed. Results A total of 112 patients were identified. Forty patients had received prophylactic antiviral therapy and none of them developed hepatitis B flare. Among the 72 patients who had not received antiviral prophylaxis, 11 of them (15.3%) experienced hepatitis B flares. Those individuals with hepatitis B flares, comparing to those without, were younger (37.4 ± 13.3 vs. 46.0 ± 11.1, p = 0.038), had higher ratio of HBeAg positivity (50 vs. 15.9%, p = 0.017), higher percentage of high hepatitis B viral load (81.8 vs. 8.3%, p = 0.002), higher maintenance glucocorticoid dose (prednisone or equivalent 22.7 ± 14.9 vs. 10.7 ± 12.4 mg, p = 0.003) and higher ratio of cyclophosphamide use (27.3 vs. 1.6%, p = 0.010). After multivariate analysis, only higher dose of maintenance glucocorticoid was related to hepatitis B flare (odds ratio, 1.08; 95% CI, 1.01-1.16). Conclusion A higher maintenance glucocorticoid dosage is associated with the risk of hepatitis B flare after glucocorticoid pulse therapy. No hepatitis B flare occurred in patients receiving prophylactic antiviral therapy before glucocorticoid pulse therapy.

Regulatory T-cells promote hepatitis B virus infection and hepatocellular carcinoma progression

Regulatory T-cells (Tregs), known for their immune suppressive function, have been reported in higher numbers, with activated phenotypes and greater potency, in hepatitis B virus (HBV)-related liver diseases than in normal conditions. The numbers, phenotypes, and function of intrahepatic and/or tumor-infiltrating Tregs in HBV-related liver diseases also differ from those of Tregs in the peripheral blood. By inhibiting the function of effector T-cells (Teffs), Tregs play a substantial role in the formation and maintenance of the liver's suppressive microenvironment, which might account for the progression of HBV-related hepatitis and hepatocellular carcinoma (HCC). In acute hepatitis B virus infection, Tregs can safeguard the liver from damage at the cost of prolonged antiviral processes, which results in chronic HBV infection in the liver. Furthermore, Tregs play a role in the development of cirrhosis, the transformation of cirrhosis to HCC, and the progression and metastasis of HCC. Higher levels of Tregs in the peripheral blood and/or tumor sites signify a poorer prognosis in HBV-related liver conditions, and observational data from mouse models and human patients support the theory that depleting Tregs may be therapeutic in HBV-related liver diseases by inducing antiviral and antitumor immunity.

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.

Immunotherapeutic interventions in chronic hepatitis B virus infection: a review

Chronic hepatitis B virus (HBV) infection is a public health challenge worldwide. Antiviral agents (nucleos(t)ide analogues, NAs) and immune-based therapies (IFN-α or Pegylated-IFN-α) are two therapeutic approaches available currently against chronic hepatitis B (CHB). However, these approaches are associated with the development of acquired drug resistance or poor response rates and are accompanied by numerous side effects. Furthermore, due to defective innate and adaptive immune responses, HBV cannot be effectively controlled or completely eliminated, which may ultimately result in liver decompensation and hepatocelluar carcinoma. The imperative for development of new approaches targeting CHB cannot be overstated. Various immunotherapeutic interventions have been tried as adjuvants to inhibit HBV replication. In this paper, we will review immunotherapeutic interventions in the treatment of CHB.

Telbivudine decreases proportion of peripheral blood CD4+CD25+CD127low T cells in parallel with inhibiting hepatitis B virus DNA

Regulatory T cells (Treg) have significant roles in the immunopathology of patients with chronic hepatitis B (CHB) and exhibit an evident correlation with antiviral immunity when antiviral therapy is applied. In order to investigate how circulating Tregs are affected by telbivudine treatment and its significance in patients with CHB, peripheral blood mononuclear cells (PBMCs) were isolated and the proportions of circulating cluster of differentiation (CD)4+CD25+CD127low and CD8+CD25+ T cells of CHB patients prior to and during the three or six months of treatment were assessed and detected by flow cytometric analysis. The levels of forkhead/winged helix transcription factor (Foxp3) mRNA were also quantified using quantitative polymerase chain reaction. A significantly higher percentage of CD4+CD25+CD127low and CD8+CD25+ T cells in the PBMCs of patients with CHB were identified compared with that of healthy individuals. Patients with CHB also demonstrated significantly higher levels of Foxp3 mRNA compared with that of healthy individuals. Following six months of telbivudine treatment, the proportion of circulating CD4+CD25+CD127low and CD8+CD25+ T cells and the relative levels of Foxp3 mRNA in patients with CHB was comparable to the proportion in healthy individuals. The proportions of circulating peripheral blood CD4+CD25+CD127low T cells were paralleled with its HBV DNA inhibition. The results of the present study indicate that telbivudine treatment reduces HBV DNA levels rapidly and indirectly affects the immune system by downregulating the proportion of circulating Treg markedly, which may be beneficial to restore the antiviral immune response.

Induction of regulatory T cells by high-dose gp96 suppresses murine liver immune hyperactivation

Immunization with high-dose heat shock protein gp96, an endoplasmic reticulum counterpart of the Hsp90 family, significantly enhances regulatory T cell (Treg) frequency and suppressive function. Here, we examined the potential role and mechanism of gp96 in regulating immune-mediated hepatic injury in mice. High-dose gp96 immunization elicited rapid and long-lasting protection of mice against concanavalin A (Con A)-and anti-CD137-induced liver injury, as evidenced by decreased alanine aminotransaminase (ALT) levels, hepatic necrosis, serum pro-inflammatory cytokines (IFN-γ, TNF-α, and IL-6), and number of IFN-γ ⁺ CD4⁺ and IFN-γ ⁺ CD8⁺ T cells in the spleen and liver. In contrast, CD4⁺CD25⁺Foxp3⁺ Treg frequency and suppressive function were both increased, and the protective effect of gp96 could be generated by adoptive transfer of Treg cells from gp96-immunized mice. In vitro co-culture experiments demonstrated that gp96 stimulation enhanced Treg proliferation and suppressive function, and up-regulation of Foxp3, IL-10, and TGF-β1 induced by gp96 was dependent on TLR2- and TLR4-mediated NF-κB activation. Our work shows that activation of Tregs by high-dose gp96 immunization protects against Con A- and anti-CD137-induced T cell-hepatitis and provides therapeutic potential for the development of a gp96-based anti-immune hyperactivation vaccine against immune-mediated liver destruction.

Immunopathogenesis and prognostic immune markers of chronic hepatitis B virus infection

Host immune responses induced by hepatitis B virus (HBV) infection not only substantially drive disease progression, but also significantly influence efficacy of antiviral treatments in HBV-infected individuals. Therefore, it is important to fully understand the course of immune pathogenesis and to find efficient immunological markers that can predict the disease progression of chronic HBV infection. This review introduces the current progress in clinical immunology and analyzes the mechanisms of antiviral effects and liver injury, which are induced by both innate and adaptive immune responses. The recently identified immunological markers indicated to be closely correlated with disease progression and antiviral efficacy during HBV infection are also summarized. Careful monitoring of these immune markers may help physicians to make decisions on when to begin or withdraw antiviral drugs, or to formulate the prognosis of acute-on-chronic liver failure (ACLF) patients in the clinic. Finally, this review highlights some novel therapeutic strategies to modulate host immunity that have been proposed to sustain antiviral control of chronic HBV infection, as well as the challenges that we are presently facing in the field.