Circulating chemokine (C-X-C Motif) receptor 5(+) CD4(+) T cells benefit hepatitis B e antigen seroconversion through IL-21 in patients with chronic hepatitis B virus infection

Varied immune responses of HBV-specific B cells in patients undergoing pegylated interferon-alpha treatment for chronic hepatitis B

BACKGROUND & AIMS

The changes in HBV-specific B cells in patients with chronic hepatitis B (CHB) undergoing pegylated interferon-α (PEG-IFNα) treatment and achieving functional cure remain unclear. We aimed to evaluate the alterations in HBV-specific B cells during treatment and therefore explored the mechanism of functional recovery of HBsAg-specific B cells.

METHODS

We included 39 nucleos(t)ide analogue-treated patients with CHB who received sequential combination therapy with PEG-IFNα and eight treatment-naïve patients. HBV-specific B cells were characterized ex vivo using fluorescently labeled hepatitis B surface and core antigens (HBsAg and HBcAg). The frequency, phenotype, and subsets of HBV-specific B cells and follicular helper T cells (Tfh cells) were detected using flow cytometry. The functionality of HBV-specific B cells was quantified through ELISpot assays.

RESULTS

During treatment, the fraction of activated memory B cells (MBCs) among HBsAg-specific B cells and the expression of IgG, CXCR3, and CD38 increased. The antibody-secretion capacity of HBsAg-specific B cells was only restored in patients achieving a functional cure after treatment and it positively correlated with serum hepatitis B surface antibody levels. The phenotype and function of HBsAg-specific B cells differed between patients with and without functional cure. Patients with functional cure exhibited IgG+ classical MBCs and plasmablasts among HBsAg-specific B cells. HBcAg-specific B cells displayed both attenuated antibody secretion with reduced IgG expression and an IgM+ atypical type of MBC after treatment, irrespective of functional cure. The number of CD40L+ Tfh cells increased after PEG-IFNα treatment and positively correlated with HBsAg-specific B-cell activation.

CONCLUSIONS

After PEG-IFNα treatment, HBsAg- and HBcAg-specific B cells exhibit various changes in antibody secretion. Their functional differences are reflected in the alterations in phenotypes and subtypes. The presence of CD40L+ Tfh cells is associated with the active recovery of HBsAg-specific B cells.

IMPACT AND IMPLICATIONS

HBV-related complications and hepatocellular carcinoma remain the leading causes of mortality from chronic liver disease worldwide, and a cure is rarely achieved with antiviral therapies. Elucidating the immunological mechanisms underlying the functional cure of patients with chronic hepatitis B offers a promising therapeutic strategy for viral clearance, e.g. via therapeutic vaccination. We analyzed the alterations in HBV-specific B cells in patients treated with pegylated interferon-α and identified novel pathways for immunotherapeutic boosting of B cell immunity.

Plasma interferon-gamma-inducible-protein 10 level as a predictive factor of spontaneous hepatitis B surface antigen seroclearance in chronic hepatitis B patients

BACKGROUND AND AIM

Spontaneous seroclearance of hepatitis B surface antigen (HBsAg) is a rare event that occurs in patients that are chronically infected with the hepatitis B virus. As the functional cure and ultimate treatment endpoint of chronic hepatitis B (CHB), HBsAg seroclearance is an important milestone in the natural history of CHB and serves great clinical value. This study aims to identify host and viral factors associated with HBsAg seroclearance.

METHODS

This is a retrospective study carried out in the Queen Mary Hospital, Hong Kong. By analyzing the plasma retrieved from the serum archive (collected during 2011-2021) of 100 CHB patients attending the hospital's liver clinic, the longitudinal cytokine profiles between the HBsAg-losers and the control groups were compared.

RESULTS

Data revealed that plasma levels of IP-10 were significantly lower at 3-5 years prior to HBsAg seroclearance compared with patients who remained HBsAg positive (P < 0.05). Receiver operating characteristic curve analysis reveals that plasma IP-10 levels at multiple time points before HBsAg seroclearance return area under receivor-operating characteristic curve (AUC) greater than 0.7. Plasma IP-10 levels at 42.39 pg/mL produced an AUC = 0.723 with 74.0% sensitivity and 75.5% specificity to predict subsequent HBsAg seroclearance in the next 3-5 years. Low plasma IP-10 identified 91.4% patients with quantitative HBsAg < 100 IU/mL who would subsequently develop HBsAg seroclearance, compared with 37% with higher plasma IP-10 levels (P < 0.001).

CONCLUSIONS

Low plasma levels of IP-10 are associated with subsequent HBsAg seroclearance, suggesting potential clinical utilities of measurement of IP-10 in predicting HBsAg seroclearance, especially among patients with low HBsAg.

Differential response of HBV envelope-specific CD4 + T cells is related to HBsAg loss after stopping nucleos(t)ide analogue therapy

BACKGROUND AND AIM

Long-term maintenance of viral control, even HBsAg loss, remains a challenge for chronic hepatitis B (CHB) patients undergoing nucleos(t)ide analogue (NA) discontinuation. This study aimed to investigate the relationship between HBV-specific T-cell responses targeting peptides spanning the whole proteome and clinical outcomes in CHB patients after NA discontinuation.

APPROACH AND RESULTS

Eighty-eight CHB patients undergoing NA discontinuation were classified as responders (remained relapse-free up to 96 weeks) or relapsers (relapsed patients who underwent NA retreatment for up to 48 weeks and reachieved stable viral control). HBV-specific T-cell responses were detected at baseline and longitudinally throughout the follow-up. We found responders had a greater magnitude of HBV polymerase (Pol)-specific T-cell responses than relapsers at baseline. After long-term NA discontinuation, simultaneously enhanced HBV Core-induced and Pol-induced responses were observed in responders. Particularly, responders with HBsAg loss possessed enhanced HBV Envelope (Env)-induced responses after short-term and long-term follow-up. Notably, CD4 + T cells accounted for the predominance of HBV-specific T-cell responses. Correspondingly, CD4-deficient mice showed attenuated HBV-specific CD8 + T-cell responses, reduced HBsAb-producing B cells, and delayed HBsAg loss; in contrast, in vitro addition of CD4 + T cells promoted HBsAb production by B cells. Besides, IL-9, rather than PD-1 blockade, enhanced HBV Pol-specific CD4 + T-cell responses.

CONCLUSION

HBV-specific CD4 + T-cell responses induced by the targeted peptide possess specificities for long-term viral control and HBsAg loss in CHB patients undergoing NA discontinuation, indicating that CD4 + T cells specific to distinct HBV antigens may endow with divergent antiviral potential.

CTLA4+CD4+CXCR5-FOXP3+ T cells associate with unfavorable outcome in patients with chronic HBV infection

BACKGROUND

A major barrier to achieving a favorable outcome of chronic HBV infection is a dysregulated HBV-specific immune response resulting from immunosuppressive features of FOXP3⁺ T cells. A better definition of FOXP3⁺ T cells is essential for improving the prognosis of HBV infection. We aimed to investigate the role of CD4⁺CXCR5^-FOXP3⁺ T cells with CTLA4 expression in patients with chronic HBV infection.

METHODS

Treatment-naïve chronic HBV-infected patients, HBV-related hepatic failure, and a longitudinal cohort of chronic hepatitis B (CHB) patients with nucleos(t)ide analogue treatment were enrolled for analysis of CD4⁺CXCR5^-FOXP3⁺ T cell responses by flow cytometry and single-cell RNA sequencing (scRNA-seq).

RESULTS

ScRNA-seq revealed that circulating CD4⁺CXCR5^-FOXP3⁺ T cells presented distinct inhibitory features compared to spleen tissue. Meanwhile, patients with treatment-naïve chronic HBV infection or with HBV-related hepatic failure showed an upregulation of immune-suppressive features (PD-1, CTLA4, GITR) on CD4⁺CXCR5^-FOXP3⁺T cells; in vitro analysis found HBeAg and HBcAg stimulation induced elevated levels of inhibitory molecules. Notably, the frequency of CTLA4⁺CD4⁺CXCR5^-FOXP3⁺ T cells was positively correlated with HBV DNA levels, and longitudinal analysis demonstrated a high frequency of this subset at 12 weeks of antiviral treatment predicted unfavorable outcome in CHB patients.

CONCLUSIONS

CTLA4⁺CD4⁺CXCR5^-FOXP3⁺ T cells are related to unfavorable outcomes in HBV-infected patients; these data indicated that alleviating CTLA4⁺CD4⁺CXCR5^-FOXP3⁺ T cells may improve the prognosis of HBV infection.

Expression Pattern of Cytokines in Patients with Chronic Hepatitis B Receiving PEGinterferon Therapy

Purpose

Chronic hepatitis B virus (CHB) infection is a worldwide health problem. Polyethylene glycol (PEG)ylated interferon (PEG-IFN) is an available therapy for CHB that has antiviral and immunomodulatory effects. However, PEG-IFN therapy is limited by the fact that only a subset of patients show a sustained response, its severe side effects, and high cost. The aim of this study was to explore novel biomarkers for the early prediction of PEG-IFN treatment response and to uncover its underlying mechanism.

Patients and Methods

We enrolled 10 paired patients with Hepatitis B e antigen (HBeAg)-positive CHB who received PEG-IFN-α2a monotherapy. Patient serum samples were collected at 0, 4, 12, 24, and 48 weeks and serum samples were collected from eight healthy people as healthy controls. For confirmation, we enrolled 27 patients with HBeAg-positive CHB receiving PEG-IFN therapy and serum samples at 0 and 12 weeks were obtained. Serum samples were analyzed using Luminex technology.

Results

Among 27 assessed cytokines, 10 cytokines were identified to have high expression levels. Among them, six cytokines had significant differences in their levels between the patients with HBeAg-positive CHB and the healthy controls (P < 0.05). Potentially, treatment response could be predicted using the early time points of 4, 12, and 24 weeks. Moreover, after 12 weeks of PEG-IFN treatment, increased levels of pro-inflammatory cytokines and decreased levels of anti-inflammatory cytokines were observed. The fold change of IP-10 between 12 weeks and 0 weeks correlated with the decrease in ALT levels from 0 to 12 weeks (r = 0.2675, P = 0.0024).

Conclusion

In patients with CHB, we observed a certain pattern in the levels of cytokines during treatment with PEG-IFN, and the cytokine IP-10 might be a potential biomarker for treatment response.

Interferon α facilitates anti-HBV cellular immune response in a B cell-dependent manner

OBJECTIVES

Dissecting the underlying mechanism of T cells remodeling mediated by interferon α (IFN-α) is indispensable for achieving an optimum therapeutic response in chronic hepatitis B (CHB) patients. However, little is known about B cells in this process. This study aims to elucidate the roles of B cells in IFN-α-mediated anti-hepatitis B virus (HBV) cellular immunity.

METHOD

The effects of B cells on IFN-α-mediated T cell response were investigated in B cell-deficient mouse model with HBV and IFN-α plasmid hydrodynamic injection. Single-cell RNA sequencing was performed to dissect the crosstalk among B cell and T cell subsets and the underlying molecule and pathway signatures on longitudinal blood samples from IFN-α-treated CHB patients.

RESULTS

B cell depletion impaired the functional T cell subsets, including HBV-specific CD8⁺ T cells, and engendered a delayed HBV clearance. IFN-α treatment boosted the response of HBV-specific CD8⁺ T cells, whereas such effects disappeared in B cell-deficient mice. The underlying mechanisms were associated with IFN-α-reinforced connections of B cells toward T cells as mediated by the antigen presentation and costimulatory functions in B cells.

CONCLUSION

IFN-α orchestrates protective HBV-specific cellular immunity in a B cell-dependent manner.

CXCL13-CXCR5 axis: Regulation in inflammatory diseases and cancer

Chemokine C-X-C motif ligand 13 (CXCL13), originally identified as a B-cell chemokine, plays an important role in the immune system. The interaction between CXCL13 and its receptor, the G-protein coupled receptor (GPCR) CXCR5, builds a signaling network that regulates not only normal organisms but also the development of many diseases. However, the precise action mechanism remains unclear. In this review, we discussed the functional mechanisms of the CXCL13-CXCR5 axis under normal conditions, with special focus on its association with diseases. For certain refractory diseases, we emphasize the diagnostic and therapeutic role of CXCL13-CXCR5 axis.

Hepatitis B Virus-Specific Cellular Immunity Contributes to the Outcome of Occult Hepatitis B Virus Infection

There is little known of immunologic factors leading to the occurrence of occult HBV infection (OBI). Specific cellular immune response to hepatitis B virus (HBV) core/pol peptides was compared between blood donor populations, including 37 OBIs, 53 chronic HBV infections (CHB), 47 resolved infections, and 56 non-infected controls, respectively. The rate of CD4⁺/CD8⁺ T cell proliferation in OBI or CHB carriers was higher than in HBV resolved and non-infected individuals (P < 0.05). The intensity of IFN-γ-secretion T-cell response of OBI carriers was highest, followed by CHB and resolved infections, and non-infected individuals (P < 0.05). The frequency of intracellular IFN-γ and IL-17A CD4⁺/CD8⁺ and IL-21 CD4⁺ T-cell responses was significantly higher in resolved infections than in OBI or CHB carriers (P < 0.05), while the level of extracellular IL-17A of peripheral blood mononuclear cells (PBMCs) was higher in OBI and CHB carriers than in resolved infections (P < 0.01). The frequency of intracellular IL-10 CD4⁺ T-cell response in CHB, OBI, and resolved infections was higher than in HBV non-infected individuals (P < 0.01). Intracellular IL-10 CD8⁺ T cell and extracellular IL-10 T-cell responses were higher in CHB than in OBI (P = 0.012) or HBV resolved infections (P < 0.01). In conclusion, the higher level of effective T-cell response with IFN-γ, IL-17A, and IL-21 contributes to resolved infection outcome, while higher levels of suppressive T-cell response with IL-10 result in HBV chronicity. OBI is an intermediary status between HBV resolved and chronic infections, in which IL-21 effector and IL-10 suppressor T-cell responses play an important role in directing the outcome of HBV infection.

T follicular helper cells improve the response of patients with chronic hepatitis B to interferon by promoting HBsAb production

BACKGROUND AND AIMS

Hepatitis B surface antigen (HBsAg) seroconversion is considered the optimal outcome of the treatment of chronic hepatitis B virus (HBV) infection. In this study, we aimed to determine the cellular and molecular mechanisms by which pegylated interferon alpha (PEG-IFN-α) improves the seroconversion rate in patients with chronic hepatitis B (CHB).

METHODS

Flow cytometry was performed using circulating T follicular helper (TFH) cells from 15 healthy individuals and 45 patients with CHB presenting different treatment responses [complete response group (CRG), incomplete response group (ICRG), and nonresponse group (NRG)] to the standard 48-week regimen of PEG-IFN-α monotherapy to examine the significance of circulating TFH cells in the therapeutic response of patients with CHB to PEG-IFN-α. In addition, the capacities of different TFH subsets to activate B cells and stimulate IgG production were assessed by performing coculture experiments.

RESULTS

Longitudinal analysis revealed specific and significant increases in the numbers of CD40L⁺CD4⁺CXCR5⁺ TFH cells in the CRG compared with the NRG and ICRG. According to the results of in vitro coculture experiments, blocking CD40-CD40L signaling, but not ICOS-ICOSL signaling, specifically inhibits B-cell activation and IgG production. HBV may impair TFH cell function by enhancing inhibitory regulatory T-cell activity. Transcriptome analysis further revealed the upregulation of CD40L, but not of ICOS, in TFH cells isolated from the CRG.

CONCLUSIONS

TFH cells, particularly those with CD40L expression, stimulate B-cell differentiation and improve the HBsAg seroconversion rate in patients with CHB treated with PEG-IFN-α monotherapy.

Cytokines and Chemokines in HBV Infection

Chronic hepatitis B virus (HBV) infection remains a leading cause of hepatic inflammation and damage. The pathogenesis of chronic hepatitis B (CHB) infection is predominantly mediated by persistent intrahepatic immunopathology. With the characterization of unique anatomical and immunological structure, the liver is also deemed an immunological organ, which gives rise to massive cytokines and chemokines under pathogenesis conditions, having significant implications for the progression of HBV infection. The intrahepatic innate immune system is responsible for the formidable source of cytokines and chemokines, with the latter also derived from hepatic parenchymal cells. In addition, systemic cytokines and chemokines are disturbed along with the disease course. Since HBV is a stealth virus, persistent exposure to HBV-related antigens confers to immune exhaustion, whereby regulatory cells are recruited by intrahepatic chemokines and cytokines, including interleukin-10 and transforming growth factor β, are involved in such series of causal events. Although the considerable value of two types of available approved treatment, interferons and nucleos(t)ide analogues, effectively suppress HBV replication, neither of them is sufficient for optimal restoration of the immunological attrition state to win the battle of the functional or virological cure of CHB infection. Notably, cytokines and chemokines play a crucial role in regulating the immune response. They exert effects by directly acting on HBV or indirectly manipulating target immune cells. As such, specific cytokines and chemokines, with a potential possibility to serve as novel immunological interventions, combined with those that target the virus itself, seem to be promising prospects in curative CHB infection. Here, we systematically review the recent literature that elucidates cytokine and chemokine-mediated pathogenesis and immune exhaustion of HBV infection and their dynamics triggered by current mainstream anti-HBV therapy. The predictive value of disease progression or control and the immunotherapies target of specific major cytokines and chemokines in CHB infection will also be delineated.

Hepatocyte-derived L-carnitine restricts hepatitis B surface antigen loss through an immunosuppressive effect on germinal center-related immune cells

BACKGROUND

The outcome of hepatitis B virus (HBV) infection is significantly affected by host immune response; herein, we aim to dissect the effect of L-carnitine (L-Cn) on germinal center (GC)-related immune cells and the influence on the prognosis of HBV infection.

METHODS

In vitro and in vivo experiments were performed in patients with chronic HBV infection and a hydrodynamic injection mouse model.

RESULTS

In vitro assays revealed that L-Cn significantly reduced GC-related immune responses and enhanced immunosuppressive profiles. Intriguingly, L-Cn released from lysed hepatocytes was associated with the degree of liver damage. Besides, the administration of L-Cn in an HBV mouse model resulted in delayed clearance of HBsAg in serum and decreased GC formation in the spleen. Notably, patients with HBsAg loss showed decreased plasma L-Cn levels, and longitudinal observations found that low baseline levels of L-Cn were associated with a favorable treatment response in chronic hepatitis B patients.

CONCLUSIONS

The suppressive effect of hepatocyte-derived L-Cn on GC-related immune cells may contribute to the inability of HBsAg clearance in chronic HBV infection, indicating that L-Cn might serve as a potential therapeutic target for the treatment of HBV infection.

High L-Carnitine Levels Impede Viral Control in Chronic Hepatitis B Virus Infection

Persistent antigen exposure during chronic hepatitis B infection leads to exhausted immune responses, thus impeding viral control. In recent years, immunometabolism opens new therapeutic possibilities for the modulation of immune responses. Herein, we investigated the immunomodulatory effect of L-carnitine (L-Cn) on immune cells in chronic HBV infection. In this study, 141 treatment-naïve patients with chronic HBV infection, 38 patients who achieved HBsAg loss following antiviral treatment, and 47 patients who suffered from HBV-related HCC from real-life clinical practice were recruited. The plasma L-Cn levels were measured by ELISA. RNA sequencing was conducted to define the transcriptional profiles of peripheral blood mononuclear cells after L-Cn stimulation. In vitro assays were performed to assess the effect of L-Cn on immune cells; the frequencies and function of immune cells were analyzed by flow cytometry. We found that compared with patients with HBsAg loss, patients with HBsAg positivity and patients who suffered from HBV-related HCC had higher levels of L-Cn, and the plasma levels of L-Cn in the HBeAg-positive chronic hepatitis patients who had elevated ALT were significantly higher than that of HBeAg-negative chronic infection and HBsAg loss groups. Moreover, a positive correlation between plasma levels of L-Cn and HBsAg levels was found. Additionally, RNA sequencing analysis demonstrated that L-Cn altered the transcriptional profiles related to immune response. In vitro assays revealed that L-Cn suppressed the proliferation of and IFN-γ production by CD4⁺ and CD8⁺ T cells. It also down-regulated the proliferation and IgG production of B cells. Notably, L-Cn enhanced IL-10 secretion from regulatory T cells and up-regulated the expression of inhibitory receptors on T cells. Moreover, a variant in CPT2 (rs1799821) was confirmed to be associated with L-Cn levels as well as complete response in CHB patients following Peg-IFNα antiviral therapy. Taken together, the immunosuppressive properties of L-Cn may hinder the control of HBV in chronic HBV infection, implicating that L-Cn manipulation might influence the prognosis of patients with HBV infection.

CD4+ T Cells in Chronic Hepatitis B and T Cell-Directed Immunotherapy

The impaired T cell responses observed in chronic hepatitis B (HBV) patients are considered to contribute to the chronicity of the infection. Research on this impairment has been focused on CD8⁺ T cells because of their cytotoxic effector function; however, CD4⁺ T cells are crucial in the proper development of these long-lasting effector CD8⁺ T cells. In this review, we summarize what is known about CD4⁺ T cells in chronic HBV infection and discuss the importance and opportunities of including CD4⁺ T cells in T cell-directed immunotherapeutic strategies to cure chronic HBV.

IL-21-Deficient T Follicular Helper Cells Support B Cell Responses Through IL-27 in Patients With Chronic Hepatitis B

Chronic Hepatitis B (CHB) affects over 350 million people worldwide. Current treatment does result in reduced complications; however, a cure (development of antibodies to the S antigen) is not achieved, requiring life-long therapy. Humoral responses contribute to viral elimination by secreting neutralizing antibodies; though, effective induction of humoral immunity require CD4T cell differentiation into T follicular helper (T_FH) cells that support B cell response through interleukin-21 (IL-21). In CHB, mechanism of T_FH-B interactions is seldom described. During CHB, T_FH cells are defective in producing IL-21 in response to hepatitis B surface antigen (HBsAg). However, regardless of low IL-21, T_FH cells efficiently support B cell responses by producing interleukin-27 (IL-27), which directs the formation of plasmablasts and plasma cells from memory and naïve B cells by enhancing B lymphocyte-induced maturation protein-1. IL-27 not only improved total antibody production but HBsAg-specific IgG and IgM secretion that are essential for viral clearance. Importantly, IL-27+T_FH cells were significantly associated with HBV DNA reduction. Therefore, these findings imply a novel mechanism of T_FH mediated B cell help in CHB and suggest that IL-27 effectively compensate the function of IL-21 by supporting T_FH-B cell function, required for protective antibody response and may contribute to viral clearance by providing potential target for achieving a functional cure.

Serum IL-21 levels predict HBeAg decline during rescue therapy in patients with partial response to nucleos(t)ide analogues

To investigate whether IL-21 levels predict treatment outcomes of salvage therapy among patients with suboptimal response (SOR) to nucleos(t)ide analogues (NAs), serum IL-21 levels were measured in a prospective cohort of hepatitis B e antigen (HBeAg)-positive patients with SOR to antiviral therapy. The patients switched therapy to entecavir (ETV) with or without adefovir (ADV) for 104 weeks. IL-21 levels at treatment week 12 in patients who achieved HBeAg loss with undetectable levels of hepatitis B virus (HBV)-DNA at week 104 were the primary endpoint and the results were compared with those of corresponding patients without such an endpoint. Furthermore, IL-21 levels at treatment week 12 in patients who achieved an HBeAg-level decline at week 104 were assessed as the secondary endpoint. Among 24 enrolled patients with SOR to ADV (n=21), telbivudine (n=2) or ETV (n=1), the median (10-90th percentile) levels of HBeAg, HBV-DNA and ALT at baseline were 2.7 (0.2-3.1) log₁₀ S/CO, 5.2 (3.5-7.5) log₁₀ IU/ml and 0.9 (0.5-3.1) upper limit of normal, respectively. Comparison of the patients with and without HBeAg loss at week 104 indicated that their mean IL-21 levels did not significantly differ at week 12 (63.0±14.4 vs. 55.9±10.5 pg/ml; P=0.26). In the secondary endpoint analyses of patients with and without HBeAg level decline, the elevated levels of IL-21 at the first 12 weeks were significantly higher in the decline group (15.6±8.3 vs. 3.1±13.2 pg/ml; P=0.03). Following adjustment for confounding factors, the elevated levels of IL-21 from baseline to week 12 independently predicted an HBeAg level decline at week 104 (odds ratio=1.137, R²=0.23; P=0.047). In conclusion, the serum IL-21 levels at the first 12 weeks during the salvage therapy independently predicted HBeAg level decline at treatment week 104 in patients with SOR to NAs (ClinicalTrials.gov identifier: NCT01829685; date of registration, April 2013).

Toll-Like Receptor 8 Agonist GS-9688 Induces Sustained Efficacy in the Woodchuck Model of Chronic Hepatitis B

BACKGROUND AND AIMS

GS-9688 (selgantolimod) is an oral selective small molecule agonist of toll-like receptor 8 in clinical development for the treatment of chronic hepatitis B. In this study, we evaluated the antiviral efficacy of GS-9688 in woodchucks chronically infected with woodchuck hepatitis virus (WHV), a hepadnavirus closely related to hepatitis B virus.

APPROACH AND RESULTS

WHV-infected woodchucks received eight weekly oral doses of vehicle, 1 mg/kg GS-9688, or 3 mg/kg GS-9688. Vehicle and 1 mg/kg GS-9688 had no antiviral effect, whereas 3 mg/kg GS-9688 induced a >5 log₁₀ reduction in serum viral load and reduced WHV surface antigen (WHsAg) levels to below the limit of detection in half of the treated woodchucks. In these animals, the antiviral response was maintained until the end of the study (>5 months after the end of treatment). GS-9688 treatment reduced intrahepatic WHV RNA and DNA levels by >95% in animals in which the antiviral response was sustained after treatment cessation, and these woodchucks also developed detectable anti-WHsAg antibodies. The antiviral efficacy of weekly oral dosing with 3 mg/kg GS-9688 was confirmed in a second woodchuck study. The antiviral response to GS-9688 did not correlate with systemic GS-9688 or cytokine levels but was associated with transient elevation of liver injury biomarkers and enhanced proliferative response of peripheral blood mononuclear cells to WHV peptides. Transcriptomic analysis of liver biopsies taken prior to treatment suggested that T follicular helper cells and various other immune cell subsets may play a role in the antiviral response to GS-9688.

CONCLUSIONS

Finite, short-duration treatment with a clinically relevant dose of GS-9688 is well tolerated and can induce a sustained antiviral response in WHV-infected woodchucks; the identification of a baseline intrahepatic transcriptional signature associated with response to GS-9688 treatment provides insights into the immune mechanisms that mediate this antiviral effect.

Expanded circulating follicular dendritic cells facilitate immune responses in chronic HBV infection

Background

The restoration of host hepatitis B virus (HBV)-specific antiviral immunity is an effective strategy for hepatitis B recovery. Follicular dendritic cells (FDCs) play a crucial role in immune regulation. The goal of the present study was to investigate the characteristics and functions of FDCs in chronic HBV infection.

Methods

The frequencies of FDCs in peripheral blood, liver, and spleen were measured in patients with chronic HBV infection. Isolated FDCs from splenic tissues of HBV-related liver cirrhosis-induced hypersplenism patients were cultured with autologous intrasplenic CD4⁺ T cells and CD19⁺ B cells.

Results

We observed that patients with chronic HBV infection had a significantly increased frequency of circulating FDCs compared to that of healthy controls. Additionally, the frequency of circulating FDCs was positively correlated with that of intrahepatic and intrasplenic counterparts. Moreover, positive correlations were observed between the frequencies of circulating FDCs and plasmablast and memory B cells, as well as C-X-C motif chemokine receptor type 5 (CXCR5)⁺CD4⁺ T cells and CXCR5⁺CD8⁺ T cells. Notably, in vitro experimental results demonstrated that FDCs derived from splenic tissues of chronic HBV patients facilitated interferon-γ and interleukin-21 production from autologous intrasplenic CD4⁺ T cells and promoted the proliferation of autologous intrasplenic CD19⁺ B cells.

Conclusions

Expanded FDCs in patients with chronic HBV infection may favor host immune responses against HBV. The identification of this unique population of cell may contribute to a better understanding of the immune regulatory mechanisms associated with chronic HBV infection and provide a potential immunotherapeutic target for this disease.

CXCR5+ CD4+ T cell subsets and their relationship to immune dysfunction in chronic hepatitis B-associated liver cirrhosis

BACKGROUND AND AIM

Hepatitis B-associated liver cirrhosis (HBC) leads to profound alterations of immune systems, especially disruptions of B cell immune responses. CXCR5⁺ CD4⁺ T cells (including T follicular helper [Tfh] cells and T follicular regulatory [Tfr] cells) are responsible for the regulation of B cell functions. The aim of this study was to dissect the roles of CXCR5⁺ CD4⁺ T cell subset in B cell disruption caused by HBC.

METHODS

Forty-one patients with HBC and 15 healthy controls were enrolled in this study. ELISA, flow cytometric analysis, and cell coculture were performed to analyze the properties of Tfh and Tfr.

RESULTS

We observed significantly decreased memory B cells and increased plasma B cells in HBC patients, as well as significant upregulation of lipopolysaccharide binding protein and soluble CD14 in plasma of decompensated HBCs patients. The downregulation of Tfh17 was observed in HBC patients with spontaneous bacterial peritonitis compared with those without. The decrease of Tfh17 was paralleled with Child-Pugh grade and negatively correlated with plasma B cells and soluble CD14 in HBC patients. Interleukin (IL)-21⁺ Tfh of HBC patients was also downregulated compared with healthy controls, and it was positively correlated with memory B cells and the upregulation of IL-10⁺ Tfr. It was then revealed that Tfr could inhibit the secretion of IL-21 by Tfh, and the blocking of IL-10 could diminish this effect.

CONCLUSIONS

The changes of the frequency and function of Tfh and Tfr may play an important role in disease progression and immune dysfunction of HBC.

CXCL13-mediated recruitment of intrahepatic CXCR5+CD8+ T cells favors viral control in chronic HBV infection

BACKGROUND & AIMS

Although CD8⁺T cell exhaustion hampers viral control during chronic HBV infection, the pool of CD8⁺T cells is phenotypically and functionally heterogeneous. Therefore, a specific subpopulation of CD8⁺T cells should be further investigated. This study aims to dissect a subset of CD8⁺T cells expressing C-X-C motif chemokine receptor 5 (CXCR5) in chronic HBV infection.

METHODS

The frequency of CXCR5⁺CD8⁺T cells and the levels of C-X-C motif chemokine ligand 13 (CXCL13), a chemokine of CXCR5, were measured in patients with chronic HBV infection. C57BL/6, interleukin (IL)-21 receptor- or B cell-deficient mice were hydrodynamically injected with pAAV-HBV1.2 plasmids. Phenotype and functions of peripheral and intrahepatic CXCR5⁺ and CXCR5^-CD8⁺T cells were assessed.

RESULTS

CXCR5⁺CD8⁺T cells were partially exhausted but possessed a stronger antiviral ability than the CXCR5^- subset in patients with chronic HBV infection; moreover, CXCR5⁺CD8⁺T cells were associated with a favorable treatment response in patients with chronic hepatitis B (CHB). High levels of CXCL13 from patients with CHB facilitated the recruitment of intrahepatic CXCR5⁺CD8⁺T cells, and this subpopulation produced high levels of HBV-specific interferon (IFN)-γ and IL-21. Notably, PD1 (programmed death 1) blockade and exogenous IL-21 enhanced the production of IFN-γ. More strikingly, mice injected with CXCR5⁺CD8⁺T cells showed remarkably decreased expression of HBsAg. Additionally, an impaired production of HBV-specific IFN-γ from intrahepatic CXCR5⁺CD8⁺T cells was observed in IL-21 receptor- or B cell-deficient mice.

CONCLUSION

CXCL13 promotes the recruitment of CXCR5⁺CD8⁺T cells to the liver, and this subpopulation improves viral control in chronic HBV infection. The identification of this unique subpopulation may contribute to a better understanding of CD8⁺T cell functions and provide a potential immunotherapeutic target in chronic HBV infection.

LAY SUMMARY

Exhaustion of CD8⁺ T cells is an important factor in the development of chronic hepatitis B virus (HBV) infection. CD8⁺ T cells expressing the receptor CXCR5 are partially exhausted, but have potent antiviral activity, as they produce high levels of HBV-specific cytokines in chronic HBV infection. Increased expression of CXCL13 within the liver facilitates the recruitment of CXCR5⁺CD8⁺T cells and establishes effective immune control of HBV infection.

TNF-α/IFN-γ profile of HBV-specific CD4 T cells is associated with liver damage and viral clearance in chronic HBV infection

BACKGROUND & AIMS

The role of hepatitis B virus (HBV)-specific CD4 T cells in patients with chronic HBV infection is not clear. Thus, we aimed to elucidate this in patients with chronic infection, and those with hepatitis B flares.

METHODS

Through intracellular IFN-γ and TNF-α staining, HBV-specific CD4 T cells were analyzed in 68 patients with chronic HBV infection and alanine aminotransferase (ALT) <2x the upper limit of normal (ULN), and 28 patients with a hepatitis B flare. HBV-specific HLA-DRB1*0803/HLA-DRB1*1202-restricted CD4 T cell epitopes were identified.

RESULTS

TNF-α producing cells were the dominant population in patients' HBV-specific CD4 T cells. In patients with ALT <2xULN, both the frequency and the dominance of HBV-specific IFN-γ producing CD4 T cells increased sequentially in patients with elevated levels of viral clearance: HBV e antigen (HBeAg) positive, HBeAg negative, and HBV surface antigen (HBsAg) negative. In patients with a hepatitis B flare, the frequency of HBV core-specific TNF-α producing CD4 T cells was positively correlated with patients' ALT and total bilirubin levels, and the frequency of those cells changed in parallel with the severity of liver damage. Patients with HBeAg/HBsAg loss after flare showed higher frequency and dominance of HBV-specific IFN-γ producing CD4 T cells, compared to patients without HBeAg/HBsAg loss. Both the frequency and the dominance of HBV S-specific IFN-γ producing CD4 T cells were positively correlated with the decrease of HBsAg during flare. A differentiation process from TNF-α producing cells to IFN-γ producing cells in HBV-specific CD4 T cells was observed during flare. Eight and 9 HBV-derived peptides/pairs were identified as HLA-DRB1*0803 restricted epitopes and HLA-DRB1*1202 restricted epitopes, respectively.

CONCLUSIONS

HBV-specific TNF-α producing CD4 T cells are associated with liver damage, while HBV-specific IFN-γ producing CD4 T cells are associated with viral clearance in patients with chronic HBV infection.

LAY SUMMARY

TNF-α producing cells are the dominant population of hepatitis B virus (HBV)-specific CD4 T cells in patients with chronic HBV infection. This population of cells might contribute to the aggravation of liver damage in patients with a hepatitis B flare. HBV-specific IFN-γ producing CD4 T cells are associated with HBV viral clearance. Differentiation from HBV-specific TNF-α producing CD4 T cells into HBV-specific IFN-γ producing CD4 T cells might favor HBV viral clearance.

Genetic variations in the CXCR5 gene decrease the risk of clinical relapse after discontinuation of nucleos(t)ide analogue therapy in patients with chronic hepatitis B

Discontinuation of nucleos(t)ide analogue (NA) therapy in patients with chronic hepatitis B (CHB) remains a global but controversial problem. Clinical outcomes of NA cessation depend on the interplay between viral factors and host immunity. Recent studies have shown that genetic polymorphisms might influence the immune response in chronic HBV infection. A total of 33 single-nucleotide polymorphisms (SNPs) from 16 genes (BCL6, CD40, CD40L, CTLA-4, CXCL13, CXCR5, ICOS, IL-21, HLA-C, NTCP, UBE2L3, STAT4, IFN-λ3, CYP27B1, INST10, and IPS1) were selected and analyzed in 106 CHB patients enrolled in an off-treatment cohort. Significantly unbalanced distributions between patients who experienced clinical relapse and those who did not were found regarding two SNPs, rs676925 in CXCR5 and rs733618 in CTLA-4. Furthermore, the genotype 'GC' of rs676925 were associated with decreased risk of clinical relapse, implicating that rs676925 may serve as a protective factor for HBV control and facilitate a virus-specific immune response. We also compared the expression of CXCR5 in lymphocytes and its ligand CXCL13 in plasma between different genotypes of rs676925. However, no significant differences were observed. In conclusion, this study suggested that the rs676925 'GC' genotype of the CXCR5 gene were associated with decreased risk of clinical relapse after discontinuation of long-term NA therapy in CHB patients.

Interleukin 21 Reinvigorates the Antiviral Activity of Hepatitis B Virus (HBV)-Specific CD8+ T Cells in Chronic HBV Infection

BACKGROUND

Strategies that target functional recovery of exhausted hepatitis B virus (HBV)-specific CD8+ T cells are beneficial for viral control, but the potential for interleukin 21 (IL-21) to rescue CD8+ T-cell function is not well understood.

METHODS

We investigated the effect of IL-21 on CD8+ T-cell responses by phenotypic and functional analysis of samples from patients with chronic HBV infection and a mouse model with HBV expression.

RESULTS

IL-21 promoted the proliferative capacity of HBV-specific CD8+ T cells and down-regulated expression of the inhibitory receptors programmed death 1 and T-cell immunoglobulin domain and mucin domain 3. Additionally, IL-21 boosted the production of interferon-γ, granzyme B, and CD107a in HBV-specific CD8+ T cells and enhanced the cytolytic activity of CD8+ T cells against HepG2.2.15 cells. Notably, an HBV mouse model established from IL-21 receptor knockout mice showed significantly decreased frequency of HBV-specific CD8+ T cells and increased levels of serum hepatitis B surface antigen (HBsAg). Meanwhile, administration of recombinant mouse IL-21 in an HBV mouse model established from wild-type mice resulted in enhanced functionality of HBV-specific CD8+ T cells and accelerated HBsAg clearance.

CONCLUSIONS

IL-21 enhances the antiviral effect of HBV-specific CD8+ T cells, suggesting that it may contribute to viral clearance in chronic HBV infection.

HBV coinfection with HCV alters circulating Tfh cell distribution and impairs HCV neutralizing antibody responses

Hepatitis C virus (HCV) and hepatitis B virus (HBV) coinfection reciprocally influences viral replication and host defence responses. This study aimed to investigate the impact of HBV coinfection on circulating T follicular helper cell (cTfh) distribution and the HCV neutralizing antibody (nAb) response. HCV neutralizing antibody responses were measured in individuals with HCV monoinfection (n = 83) and HBV/HCV coinfection (n = 78) using the HCV pseudoparticle neutralization assay. The frequencies of cTfh cells and their subsets in HCV monoinfection (n = 34) and HBV/HCV coinfection (n = 30) were analysed by flow cytometry. The correlations of clinical parameters, cTfh cells and neutralizing antibody responses were analysed. Compared with HCV monoinfection, the HBV coinfection group showed significantly lower HCV neutralizing antibody responses (P < 0.001) and a decreased frequency of circulating Th1-like Tfh cells (Tfh1) (P = 0.004). In HCV monoinfection, the frequency of the Tfh1 subset was positively correlated with HCV neutralizing antibody responses (R = 0.378, P = 0.03), but this correlation was lost under HBV/HCV coinfection (R = 0.115, P = 0.551). In contrast, the frequency of circulating Th2-like Tfh cells (Tfh2) was negatively correlated with the HCV neutralizing antibody responses (R = 0.404, P = 0.003). Further analysis showed that HBV coinfection enhanced the Tfh2 subset composition within cTfh cells (P < 0.001), which was associated with serum HBsAg in HBV/HCV coinfection (R = 0.521, P = 0.003). As expected, HBsAg also exhibited an inverse association with HCV neutralizing antibody responses in HBV/HCV coinfection (R = 0.59, P < 0.001). In contrast to HCV monoinfection, HBV/HCV coinfection leads to altered cTfh cell distribution and impaired HCV neutralizing antibody responses, which are associated with HBsAg. These findings will be helpful for better understanding the immunopathogenesis of HBV/HCV coinfection.

Circulating CXCR3+ Tfh cells positively correlate with neutralizing antibody responses in HCV-infected patients

Circulating T follicular helper (cTfh) cells have been identified as counterparts of germinal center Tfh (GC Tfh) cells in humans and can support T-dependent B cell maturation and antibody production in vitro. However, the role of cTfh cells in neutralizing antibody (nAb) responses in HCV infection remains unclear. Here, we characterized the phenotype and function of cTfh cells and demonstrated the associations of cTfh cells and their subsets with nAb responses in HCV infection. A total of 38 HCV-infected individuals and 28 healthy controls were enrolled from a pool of injection drug users. The frequency and function of blood Tfh cells were analyzed by flow cytometry. The titers and breadths of serum nAbs were measured using HCV pseudo-particle neutralization assays. Herein, we report several key observations. First, HCV infection skewed cTfh toward CXCR3⁺ cTfh cell differentiation. Second, the frequency of CXCR3⁺ cTfh cells positively correlated with HCV nAb titers and breadths. Third, CXCR3⁺ cTfh cells showed higher expression of Tfh-associated molecules (PD-1, ICOS, IL-21, Bcl-6) compared with CXCR3⁻ cTfh cells from individuals with HCV infection. Coculture of cTfh cells and autologous memory B cells in vitro indicated that CXCR3⁺ cTfh cells show a superior ability to support HCV E2-specific B cell expansion compared with CXCR3⁻ cTfh cells from individuals with HCV infection. HCV infection skews cTfh cells toward CXCR3-biased Tfh cell differentiation, which positively correlates with the magnitude and breadth of the HCV nAb response. It is our hope that these findings will provide insights for the rational design of a nAb-based HCV vaccine.

Toward Curative Immunomodulation Strategies for Chronic Hepatitis B Virus Infection

Chronic hepatitis B virus (HBV) infection remains a major cause of morbidity and mortality worldwide. HBV surface antigen loss is considered a functional cure and is an ideal goal for antiviral therapy. However, current treatment regimens, including nucleos(t)ide analogues or interferons monotherapy and combination therapy, rarely achieve this goal in chronic hepatitis B patients. Nucleos(t)ide analogues (NAs), as well as many direct antiviral drugs in ongoing development, are able to inhibit HBV replication and gene expression, but it is hard to achieve immune control and prevent recurrence after therapy cessation. Host immunity, especially HBV-specific T cell response, is proven to play a critical role in control or clearance of HBV infection. Considering HBV chronically infected patients display varying degrees of dysfunction regarding their immune system, novel approaches to enhancing antiviral immune responses are necessary in order to combine with current antiviral agents. In this Review, we focus on the role of innate and adaptive immune responses in HBV immunopathogenesis and discuss attractive strategies or drugs that aim to activate or rebuild antiviral immunity to achieve the goal of an HBV functional cure.

Cytokine and chemokine signatures associated with hepatitis B surface antigen loss in hepatitis B patients

BACKGROUND

The clearance of hepatitis B surface antigen (HBsAg) loss, defined as functional cure, is a clinical target in patients with chronic hepatitis B (CH). To understand the immune responses underlying functional cure, we evaluated cytokine and chemokine expression profiles from patients with resolving and nonresolving acute hepatitis B (AH).

METHODS

We cross-sectionally evaluated 41 chemokines and cytokines at the peak of hepatitis in the sera from 41 self-limited AH patients who achieved HBsAg seroconversion, 8 AH patients who failed to clear HBsAg within 1 year after the diagnosis, 8 CH patients with hepatic flare, and 14 healthy volunteers. We longitudinally examined 41 chemokines and cytokines in the sera from 4 self-limited AH patients, 3 chimpanzees inoculated with hepatitis B virus (HBV), and 2 CH patients treated with nucleotide analogs and PEG-IFN-α, one resulting in functional cure.

RESULTS

In AH patients and HBV-inoculated chimpanzees with HBsAg loss, CXCL9, CXCL10, CXCL11, CXCL13, and IL-21 were elevated at hepatitis with subsequent decline of HBsAg. Interestingly, IL-21 elevation was observed only in resolving AH patients but not in nonresolvers. CXCL13 and IL-21 elevation was not observed in CH patients who failed to attain HBsAg loss, even at hepatic flare. A concomitant increase of CXCL13 and IL-21 was significant in CH patients who attained HBsAg seroconversion with a sequential therapy.

CONCLUSION

Elevation of serum CXCL9, CXCL10, CXCL11, CXCL13, and IL-21 might be a hallmark of functional cure of AH or CH patients.

Increased CCR7loPD-1hiCXCR5+CD4+ T Cells in Peripheral Blood Mononuclear Cells Are Correlated with Immune Activation in Patients with Chronic HBV Infection

T follicular helper cells (Tfh cells) affect essential immune pathogenesis in chronic hepatitis B virus (HBV) infection. The CCR7^loPD-1^hi Tfh subset has a partial Tfh effector phenotype and is associated with active Tfh differentiation, whereas the CCR7^hiPD-1^lo Tfh subset is a resting phenotype. We recruited 20 healthy volunteers and 77 patients with chronic HBV infection, including those in the immune tolerant (IT) phase (n=19), immune clearance (IC) phase (n=20), low replicative (LR) phase (n=18), and reactivation (RA) phase (n=20). The expression of CD4, CXCR5, PD-1, and CCR7 was detected in T cells from peripheral blood by flow cytometry. The frequency of the CCR7^loPD-1^hi T subset was significantly higher in the patients than in the healthy controls (14.92±4.87% vs 12.23±2.95%, p=0.018). The frequency of this Tfh subset in the IC group (18.42%±3.08) was increased compared with the IT group (11.94±2.87%, p=0.001) and LR group (13.65±4.93%, p=0.031) and was higher in the RA group than in the IT group (16.03±5.37% vs 11.94±2.87%, p=0.030). We observed a weak positive correlation between the CCR7^loPD-1^hi Tfh subset population and the alanine transaminase (ALT) level (r=0.370, p=0.001). The CCR7^loPD-1^h Tfh subset in the chronic HBV-infected patients was elevated to various degrees among the different immune phases. CCR7^loPD-1^hiCXCR5⁺CD4⁺ T cells are correlated with the immune status of chronic HBV infection patients and may be developed as a potential indicator for antiviral treatment.

PD-1 blockade partially recovers dysfunctional virus-specific B cells in chronic hepatitis B infection

Chronic HBV (CHB) infection suppresses virus-specific T cells, but its impact on humoral immunity has been poorly analyzed. Here, we developed a dual-staining method that utilizes hepatitis B virus (HBV) surface antigens (HBsAg) labeled with fluorochromes as "baits" for specific ex vivo detection of HBsAg-specific B cells and analysis of their quantity, function, and phenotype. We studied healthy vaccinated subjects (n = 18) and patients with resolved (n = 21), acute (n = 11), or chronic (n = 96) HBV infection and observed that frequencies of circulating HBsAg-specific B cells were independent of HBV infection status. In contrast, the presence of serum HBsAg affected function and phenotype of HBsAg-specific B cells that were unable to mature in vitro into Ab-secreting cells and displayed an increased expression of markers linked to hyperactivation (CD21lo) and exhaustion (PD-1). Importantly, B cell alterations were not limited to HBsAg-specific B cells, but affected the global B cell population. HBsAg-specific B cell maturation could be partially restored by a method involving the combination of the cytokines IL-2 and IL-21 and CD40L-expressing feeder cells and was further boosted by the addition of anti-PD-1 Abs. In conclusion, HBV infection has a marked impact on global and HBV-specific humoral immunity, yet HBsAg-specific B cells are amenable to a partial rescue by B cell-maturing cytokines and PD-1 blockade.

Kinetics of Interferon gamma and Interleukin-21 response following foot and mouth disease virus infection

Foot and mouth disease (FMD) is one of the most contagious diseases of cloven footed animals causing significant economic impediment in livestock production system. The immune response to FMD virus (FMDV) infection is regulated by a complex interplay between various cells, cytokines and other immune components. Based on the well established role of Interferon-gamma (IFN-γ) and Interleukin-21 (IL-21) in viral infections, this study aimed to determine expression level of these cytokines in clinically infected adults and calves; and the results were compared with those in the subclinically infected animals up to 120 days post outbreak (DPO) in a vaccinated cattle herd. The expression level of IFN-γ and IL-21 was assayed on 0, 7, 14, 28, 60, 90, and 120 DPO by enzyme linked immunosorbent assay (ELISA) with simultaneous assessment of FMDV structural protein-antibody titer against serotype 'O' by liquid phase blocking ELISA (LPBE) and nonstructural protein-antibody, a differential marker of infection, using r3AB3 indirect ELISA (r3AB3 I-ELISA). Although, the peak expression of IFN-γ was observed on 14 DPO across all categories of animals, the clinically infected animals registered a significant increase in IFN-γ level as compared to the subclinically infected population possibly due to the difference in the extent of virus replication and inflammation. The IL-21 level increased significantly during 14-28 DPO and highest expression was noticed on 28 DPO. The increase in the expression level of IFN-γ and IL-21 at 28 DPO correlated with the increase in antibody titer as determined by LPBE suggesting the role of these cytokines in augmenting immune response to FMDV infection.

Combined effect of pegylated interferon α with adefovir on renal function in Chinese patients with chronic hepatitis B

BACKGROUND

Long-term safety of treatment with hepatitis B virus (HBV) polymerase inhibitors is a concern. Adefovir dipivoxil (ADV) and/or interferon alfa (IFN-α) therapies have previously been associated with impairment of renal function. Limited data are available on the safety of combination therapy with nucleos (t)ide analogues (NAs) and IFN-α. The aim of this analysis was to assess the renal function during combined therapy with pegylated interferon α-2b (PEG-IFN-α-2b) and ADV versus PEG-IFN-α-2b alone in patients with chronic hepatitis B (CHB).

METHODS

We performed a multicenter, prospective, open-label, randomized-controlled trial of renal function data to investigate the efficacy of 48 weeks of therapy with PEG-IFN-α-2b and ADV versus PEG-IFN-α-2b alone in 102 patients with CHB in Anhui, China. Glomerular filtration rates (GFRs) were calculated by Cockcroft-Gault (CG), abbreviated Modification of Diet in Renal Disease (MDRD) study, and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation, and were tested by repeated-measures 1-way analysis of variance within groups. A linear mixed effects model for repeated measures was also used to evaluate the association between baseline information and estimated glomerular filtration rate (eGFR) changes overtime in all enrolled patients. The model considered the baseline age, sex, HBV DNA, aminotransferase, treatment group, time, and group-by-time interaction as fixed effects and incorporated random effects for individual subjects.

RESULTS

After 48 weeks of therapy and further 24 weeks of follow-up, the eGFR decreased both in patients given PEG-IFN-α-2b single therapy and combined therapy. Age, HBV DNA, and combined therapy were significant negative predictive factors for eGFR changes.

CONCLUSION

The incidence of renal adverse events in both groups was low, and the combination therapy may have delayed, but reversible renal impairment.

Expression profiles of transcription factors for special CD4+ T-cell subsets in peripheral blood mononuclear cells from patients with hepatitis B virus infection

This study is to characterize the transcription factor expression profiles for the peripheral CD4 T-cell subsets, and analyze its associations with the clinical measures of the hepatitis B virus (HBV) infection.Totally 275 subjects were included. The expression levels of transcription factors (T-bet, GATA-3, Foxp3, RORγt, and Bcl-6) in the peripheral blood mononuclear cells (PBMCs) were determined by the real-time fluorimetry quantitative PCR (FQ-PCR).Lowest expression levels of all these transcription factors were observed for the HBsAb(-) group, which were higher in the HBsAb(+) and RHB groups. The T-bet/GATA-3 ratios in the CHB and RHB groups were significantly lower than the HBsAb(-) group, whereas the RORγt/Foxp3 ratios in the AHB and RHB groups were significantly higher than the CHB and HBsAb(+) groups. Furthermore, the RORγt mRNA expression levels were significantly different among groups with different disease severities or with different alanine aminotransferase (ALT) levels. The asymptomatic carrier (AsC) group and the group with ALT ≤ 40 had the highest express level. The mRNA expression levels of T-bet, GATA-3, Foxp3, and RORγt varied along with the aspartate aminotransferase (AST) levels, with AST ≤ 40 having the highest expression levels. In addition, significant differences were observed in the transcription factor expression levels between the group with the serum HBV DNA load of (1.000-9.999) × 10 copies/mL and other groups.Expression profile of critical transcription factors for peripheral CD4 T-cell subsets may indicate clinical outcomes of HBV infection.

Role of interleukin-21 and interleukin-21 receptor polymorphisms in the treatment of HBeAg-positive chronic hepatitis B patients with peginterferon

The aim of this study was to evaluate the relationship between interleukin-21 (IL-21) and interleukin-21 receptor (IL-21R) polymorphisms and the response to peginterferon alfa (PEG-IFN α) therapy in HBeAg-positive chronic hepatitis B (CHB) patients.A total of 143 HBeAg-positive CHB patients treated for 48 weeks with PEG-IFN α and followed up for 24 weeks post-treatment were retrospectively evaluated. Genotypes analysis was performed for IL-21 polymorphisms rs907715, rs2221903, and IL-21R polymorphisms rs3093301 and rs2285452. Serum IL-21 levels were measured by enzyme-linked immunosorbent assay.The end of virological response (EVR) rate was 46.9% (67/143) at the end of treatment, the sustained virological response (SVR) rate was 43.4% (62/143) and the complete response (CR) rate was 32.1% (46/143) at 24 weeks post-treatment. Patients who carried IL-21 rs 2221903 genotype AA had a rather higher rate of EVR (response rate: 52.4%, odds ratio [OR] 0.42, 95% confidence interval [CI]: 0.19-0.91, P = .021), SVR (response rate: 47.6%, OR 0.43, 95% CI: 0.19-0.95, P = .028), and CR (response rate: 38.1%, OR 0.31, 95% CI: 0.12-0.79, P = .014) when compared to those had AG genotype. Meanwhile, IL-21rs 2221903 genotype AA was also independently associated with markedly reduced HBsAg levels (>1og10 IU/mL) after 24 weeks treatment and low HBsAg levels (<100 IU/mL) at the end of treatment. IL-21 rs907715 AG/GG genotype was independently associated with SVR (OR: 2.92, 95% CI: 0.98-8.6, P = .039; OR: 3.23, 95% CI: 1.0-10.4, P = .039). Patients with IL-21 rs907715 AG/GG genotype had higher serum IL-21 levels than those with rs907715 AA genotype (P = .021).IL-21 rs2221903 and rs907715 polymorphisms were significantly associated with the treatment response to PEG-IFN α among Chinese HBeAg-positive CHB patients.

Dysregulated Response of Follicular Helper T Cells to Hepatitis B Surface Antigen Promotes HBV Persistence in Mice and Associates With Outcomes of Patients

BACKGROUND & AIMS

Production of neutralizing antibodies against hepatitis B surface antigen (HBsAg) is dysregulated in patients with persistent hepatitis B virus (HBV) infection. We investigated mechanisms by which this immune response to the virus is disrupted and whether it can be restored to promote clearance of HBV.

METHODS

Immune-competent C57BL/6N and C57BL/6J, as well as mice deficient in follicular helper T cells (Tfh-cell-deficient), B cells, or Foxp3⁺ T-regulatory cells (Treg cell deficient), were given hydrodynamic injections of pAAV/HBV1.2 plasmids. Some mice were given injections of sorted Tfh cells, pan-B cells, Treg cells, or a blocking antibody against CTLA4. Production of antibodies against HBsAg and clearance of HBV were assessed by flow cytometry, enzyme-linked immunosorbent assay, polymerase chain reaction, and immunohistochemical analyses. We obtained blood samples from patients with HBV infection and isolated Treg cells. We measured the ability of Treg cells to suppress production of interleukin 21 (IL21) in CD4⁺ T cells.

RESULTS

Immune-competent C57BL/6N and C57BL/6J mice transfected with the plasmid encoding HBV had features of viral clearance and viral persistence observed in humans. A Tfh-cell response to HBsAg was required for clearance of HBV and was suppressed by Treg cells in mice with persistent HBV infection. Depletion of Treg cells or inhibition of Treg-cell function (with blocking antibody against CTLA4) restored the Tfh-cell response against HBsAg and clearance of HBV in mice. Impaired Tfh-cell response to HBsAg was observed in blood from patients with chronic HBV infection, responsiveness was restored by depletion of Treg cells or blocking antibody against CTLA4.

CONCLUSIONS

In studies of HBV-infected mice and blood from patients with chronic HBV infection, we found a Tfh-cell response to HBsAg of to be required for HBV clearance, and that this response was blocked by Treg cells. Inhibiting Treg-cell activity using neutralizing antibody against CTLA4 restored the ability of Tfh cells to clear HBV infection; this approach might be developed for treatment of patients with chronic HBV infection.

The Janus Face of Follicular T Helper Cells in Chronic Viral Infections

Chronic infections with non-cytopathic viruses constitutively expose virus-specific adaptive immune cells to cognate antigen, requiring their numeric and functional adaptation. Virus-specific CD8 T cells are compromised by various means in their effector functions, collectively termed T cell exhaustion. Alike CD8 T cells, virus-specific CD4 Th1 cell responses are gradually downregulated but instead, follicular T helper (T_FH) cell differentiation and maintenance is strongly promoted during chronic infection. Thereby, the immune system promotes antibody responses, which bear less immune-pathological risk compared to cytotoxic and pro-inflammatory T cell responses. This emphasis on T_FH cells contributes to tolerance of the chronic infection and is pivotal for the continued maturation and adaptation of the antibody response, leading eventually to the emergence of virus-neutralizing antibodies, which possess the potential to control the established chronic infection. However, sustained high levels of T_FH cells can also result in a less stringent B cell selection process in active germinal center reactions, leading to the activation of virus-unspecific B cells, including self-reactive B cells, and to hypergammaglobulinemia. This dispersal of B cell help comes at the expense of a stringently selected virus-specific antibody response, thereby contributing to its delayed maturation. Here, we discuss these opposing facets of T_FH cells in chronic viral infections.

CTLA‑4 interferes with the HBV‑specific T cell immune response (Review)

Hepatitis B virus (HBV) infection is a major cause of hepatic inflammation. Successful HBV clearance in patients is associated with sustained viral control by effector T cells. Compared with acute hepatitis B, chronic HBV infection is associated with the depletion of T cells, resulting in weak or absent virus-specific T cells reactivity, which is described as 'exhaustion'. This exhaustion is characterized by impaired cytokine production and sustained expression of multiple coinhibitory molecules. Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) is one of many coinhibitory molecules that can attenuate T cell activation by inhibiting costimulation and transmitting inhibitory signals to T cells. Persistent HBV infection results in the upregulation of CTLA-4 on hepatic CD8⁺ T cells. This prompts CD8⁺ T cell apoptosis, and the activation of cytotoxic T lymphocytes is blocked. Similar to CD8⁺ T cells, CD4⁺ T helper (Th) cell proliferation is hindered following CTLA-4 upregulation. In addition, the differentiation of CD4⁺ Th is polarized toward the Th2/peripherally-inducible T regulatory cell types, increasing the levels of anti-inflammatory cytokines. Conversely, the activation of proinflammatory cells (Th1 and follicular helper T) is blocked, and the levels of proinflammatory cytokines decline. This review summarizes the current literature relevant to T cell exhaustion in patients with HBV-related chronic hepatitis, and discusses the roles of CTLA-4 in T cell exhaustion.

Viral envelope-specific antibodies in chronic hepatitis B virus infection

While the cellular immune response associated with acute and chronic HBV infection has been thoroughly studied, the B cell response in chronic hepatitis B and the role of antibodies raised against the HBV envelope antigens in controlling and prevention of infection requires further investigation. The detection of anti-HBs antibodies is considered as one of the biomarkers for functional cure of chronic hepatitis B virus infection, as well as for protective immunity. Indeed, vaccine-induced neutralizing anti-HBs antibodies have been shown to protect against HBV challenge. Yet, the therapeutic potential of viral envelope-specific antibodies and the mechanism involved in protection and prevention of cell-to-cell transmission warrants additional investigative efforts. In this review, we will provide a critical overview of the available preclinical and clinical literature supporting the putative role of active and passive vaccination and neutralizing envelope-specific antibodies for therapeutic intervention in combination regimens intended to cure persistent HBV infection.

Circulating CXCR5+CD4+ T cells participate in the IgE accumulation in allergic asthma

The pathogenesis of allergic asthma is primarily characterized by abnormality in immunoglobin(Ig)E pathway, suggesting a possible role for follicular helper T cells (Tfh) in the genesis of excessive IgE accumulation. The blood chemokine (C-X-C motif) receptor 5 (CXCR)5⁺CD4⁺ T cells, known as "circulating" Tfh, share common functional characteristics with Tfh cells from germinal centers. The aim of this study was to determine the phenotypes and functions of circulating CXCR5⁺CD4⁺ T cells in allergic asthmatics. Here we found the frequency of the circulating CXCR5⁺CD4⁺ T cells was raised in allergic asthma compared with healthy control (HC). Phenotypic assays showed that activated circulating CXCR5⁺CD4⁺ T cells display the key features of Tfh cells, including invariably coexpressed programmed cell death (PD)-1 and inducible costimulator (ICOS). The frequency of interleukin IL-4⁺-, IL-21⁺-producing CXCR5⁺CD4⁺ T cells was increased in allergic asthma patients compared with HC. Furthermore, sorted circulating CXCR5⁺CD4⁺ T cells from allergic asthma patients boosted IgE production in coculture assay which could be inhibited by IL-4 or IL-21 blockage. Interestingly, IL-4⁺-, IL-21⁺-CXCR5⁺CD4⁺ T cells positively correlated with total IgE in the blood. Our data indicated that circulating CXCR5⁺CD4⁺ T cells may have a significant role in facilitating IgE production in allergic asthma patients.

Activation of intrahepatic CD4+CXCR5+ T and CD19+ B cells is associated with viral clearance in a mouse model of acute hepatitis B virus infection

The role of immunity in the pathogenesis of acute hepatitis B virus (HBV) infection is poorly understood. The purpose of this research was to define the intrahepatic immune factors responsible for viral clearance during acute HBV infection. The model of acute HBV infection was established by hydrodynamically transfecting mice with pCDNA3.1-HBV1.3 plasmids which contained a supergenomic HBV1.3-length transgene. The frequency of CD4⁺ CXCR5⁺ T cells, CD19⁺ B cells and their surface molecules in livers, spleens and peripheral blood were detected using flow cytometry. The lymphomononuclear cells isolated from the livers of transfected mice were further stimulated by HBc-derived peptides and then the frequency and cytokine secretion of HBV-specific CD4⁺CXCR5⁺ T cells were detected. We found that the frequency of CXCR5⁺ in CD4⁺ T cells was specifically increased; the expression of PD-1 was decreased while the expression of ICOS was increased on intrahepatic CD4⁺CXCR5⁺ T cells. Although the frequency of CD19⁺ B cells was not affected, the expression of PDL-1, ICOSL and IL-21R on B cells was increased in the livers of mice. The frequency of HBV-specific CD4⁺CXCR5⁺ T cells and the production of IL-21 by intrahepatic CD4⁺CXCR5⁺ T cells of mice with acute HBV infection were increased after stimulation. Furthermore, the expression of function-related molecules of intrahepatic CD4⁺CXCR5⁺ T, including Bcl-6, CXCR5, IL-6, IL-6R, IL-21 and IL-4 in the liver was increased during acute HBV infection. In conclusion, the activation of intrahepatic CD4⁺CXCR5⁺ T cells and B cells was associated with the clearance of HBV during acute infection.

Hepatitis B virus persistence in mice reveals IL-21 and IL-33 as regulators of viral clearance

Hepatitis B virus (HBV) generally causes self-limiting infection in immunocompetent adults, but establishes chronic infection in some adults and in most maternally infected infants. Factors determining clearance versus persistence are not fully understood. Hydrodynamic injection (HDI) of HBV replicon plasmid via tail vein generally results in quick clearance in immunocompetent adult mice. Here, we report the identification of strain-specific persistence of HBV in mice: one genotype B strain, designated BPS, persisted up to 33 weeks in ~50% of HDI mice. BPS persistence requires viral replication and multiple viral features. Compared to quickly cleared strains, BPS fails to induce robust post-exposure serum IL-21/IL-33 responses. Injection of IL-21-expressing or IL-33-expressing plasmids facilitates clearance of pre-established BPS persistence and protects cured mice from BPS re-challenge. IL-21 and IL-33 also induce clearance of pre-established HBV persistence in another mouse model. These data reveal IL-21 and IL-33 as potent regulators of HBV clearance and valid drug candidates.

Hepatitis B virus (HBV) establishes chronic infection in only some patients, but the mechanisms underlying clearance failure in these patients are not fully understood. Here, the authors identify and characterize an HBV strain that can persist in mice and show that IL-21 and IL-33 responses contribute to clearance.

Lower Expression of MicroRNA-155 Contributes to Dysfunction of Natural Killer Cells in Patients with Chronic Hepatitis B

MicroRNAs have been reported to be regulated in different ways in a variety of liver diseases. As a key modulator of cellular function in both innate and adaptive immunity, the role of miR-155 in chronic hepatitis B virus infection remains largely unknown. Here, we investigated the expression and function of miR-155 in chronic hepatitis B (CHB) patients. It was found that miR-155 expression in peripheral blood mononuclear cells (PBMCs) was lower in CHB patients than healthy controls (HC). Among CHB infection, immune-active (IA) patients with abnormal alanine aminotransferase (ALT) levels had relatively higher miR-155 expression in PBMCs and serum than immune-tolerant carriers, but were comparable to inactive carriers. Moreover, there was a positive correlation between miR-155 expression and ALT levels in CHB patients. Particularly, miR-155 expression in natural killer (NK) cells was significantly downregulated in IA patients compared with HC. Inversely, suppressor of cytokine signaling 1 (SOCS1), a target of miR-155, was upregulated in NK cells of IA patients. Overexpression of miR-155 in NK cells from IA patients led to a decrease in SOCS1 expression and an increase of IFN-γ production. Finally, accompanied by the normalization of ALT, miR-155 expression in PBMCs gradually decreased during telbivudine or peg-IFN-α-2a therapy. Interestingly, higher miR-155 expression at baseline was associated with better response to telbivudine therapy, but not peg-IFN-α-2a. In conclusion, our data suggested that miR-155 downregulation in NK cells of IA patients impaired IFN-γ production by targeting SOCS1, which may contribute to immune dysfunction during CHB infection. Additionally, baseline miR-155 expression could predict the treatment response to telbivudine therapy.

Dynamic Perturbations of CD4 and CD8 T Cell Receptor Repertoires in Chronic Hepatitis B Patients upon Oral Antiviral Therapy

Long-term treatment with nucleos(t)ide analogs (NUCs) can improve the antiviral T cell response in chronic hepatitis B (CHB) patients. Whether and to what extent the T cell response is improved by NUCs in the early stage leading to hepatitis B e antigen (HBeAg) seroconversion remain to be clarified. A total of 22 CHB patients undergoing 2-year telbivudine-based therapy were enrolled, including 10 exhibiting a complete response (CR) and 12 exhibiting a non-complete response (NCR) according to HBeAg seroconversion at week 52. Peripheral CD4⁺ and CD8⁺ T cells were sorted at baseline, weeks 12, and 24. The T cell receptor β chain (TCRβ) complementarity-determining region 3 was analyzed by unbiased high-throughput sequencing. Compared with NCR group, patients in CR group had a much lower percentage of persistent clonotypes (P < 0.001) but remarkably higher percentages of new and expanded clonotypes (P < 0.05) between any two time points for both CD4 and CD8 subsets. The CD4 T cells exhibited a stronger response than CD8 population in the patients. The number of new and expanded clonotypes was inversely associated with the decline of viral antigen. In conclusion, NUC-based therapy induces a broad and vigorous T cell response with rapid decline of antigenemia during the early stage of treatment. A broad T cell expansion is crucial for HBeAg seroconversion. Our findings suggest that the potent suppression of hepatitis B virus replication by NUC monotherapy complemented with additional immunomodulatory strategies may increase the likelihood of a functional cure for CHB in the future.

Functional restoration of CD56bright NK cells facilitates immune control via IL-15 and NKG2D in patients under antiviral treatment for chronic hepatitis B

Background and aims

Hepatitis B virus (HBV) is intrinsically immunogenic, with long-lasting immune control in many patients. However, the mechanisms and key cell types underlying effective immune control are incompletely understood.

Methods

We studied the restoration of natural killer (NK) cell numbers and function post antiviral treatment in 52 hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) patients who received telbivudine (LdT) for 48 weeks. Blood samples were collected at week 0, 12, 24, 36, and 48 and tested for HBV DNA, hepatitis B surface antigen (HBsAg), HBeAg, liver enzymes, and NK cell parameters.

Results

Compared with baseline, the number of peripheral CD3⁻CD56^bright NK cells increased significantly from week 24 to 48, especially in patients with baseline alanine transaminase (ALT) two- to fivefold the upper line of normal (ULN) or HBV DNA <9 log₁₀ copies/ml. Expression (number and density) of activating receptors NKG2D and NKp46 on CD3⁻CD56^bright NK cells was enhanced, while inhibitory receptor NKG2A decreased. Notably, numbers of CD3⁻CD56^bright or NKG2D⁺CD3⁻CD56^bright NK cells were significantly better restored in patients with HBeAg seroconversion. NK cell activating serum interleukin 15 (IL-15) was significantly increased during LdT treatment, especially in HBeAg seroconverters. LdT significantly enhanced expression of NKG2D and IL-15 in cultures of purified peripheral NK cells from treatment-naïve HBeAg-positive CHB patients.

Conclusions

Functional restoration of CD56^bright NK cells via upregulation of IL-15 and NKG2D is a novel activity of LdT and likely other antivirals, independent of its effect on HBV replication. This also demonstrates the importance of host immune restoration in controlling chronic HBV infection.

Electronic supplementary material

The online version of this article (doi:10.1007/s12072-017-9803-4) contains supplementary material, which is available to authorized users.

Serum hepatitis B core antibody as a biomarker of hepatic inflammation in chronic hepatitis B patients with normal alanine aminotransferase

Our previous studies unexpectedly indicated that the level of serum hepatitis B core antibody (anti-HBc) was positively correlated with the serum alanine aminotransferase (ALT) level. The aim of this study was to determine whether anti-HBc could serve as a potential biomarker for the detection of liver inflammation in chronic hepatitis B (CHB) patients, especially in patients with normal ALT levels. Serum anti-HBc levels were quantified in 655 treatment-naïve CHB patients, including 45 patients who underwent two liver biopsies (baseline phase and the 78^th weeks of antiviral-treatment). Serum anti-HBc levels increased significantly along with the increasing histology activity index (HAI) score. After antiviral-treatment, patients with HAI score reduction had significant decline in serum anti-HBc level. Multivariate analysis showed that anti-HBc was independently associated with moderate-to-severe hepatic inflammation in patients with normal ALT level. Furthermore, serum anti-HBc showed a high diagnostic accuracy for predicting moderate-to-severe inflammation in both hepatitis B e antigen (HBeAg)-positive and HBeAg-negative CHB patients with normal ALT levels (area under the curve, AUC = 0.87 and 0.75; respectively). Thus, anti-HBc may be a strong indicator for assessing the hepatic inflammatory degree and used for antiviral treatment decisions in CHB patients with normal ALT levels.

Assessment of sequence homology and immunologic cross-reactivity between tree shrew (Tupaia belangeri) and human IL-21

Many studies have indicated that the expression of interleukin-21 (IL-21) is associated with the pathogenesis of certain liver diseases. However, in alternative animal models of liver diseases, it remains unknown whether the tree shrew could be utilized to analyze the relationship between IL-21 and liver diseases. Here, the phylogenetic tree, sequence alignment and protein structure model of tree shrew and human IL-21 were analyzed using bioinformatics software. A pEGFP-N3/tsIL-21 eukaryotic expression vector of tree shrew IL-21 (tsIL-21) was constructed, and IL-21 expression by the vector-transfected Huh7 cells was evaluated using the newly established quantitative real-time PCR and immunologic protocols for assessing human IL-21. The cytokine profiles were also evaluated in tree shrew spleen lymphocytes induced by recombinant human IL-21 or concanavalin A. It was found that the coding sequence (CDS) of tsIL-21 amplified from spleen lymphocytes belonged to the predicted sequence. The tsIL-21 was closely clustered with primate IL-21 rather than rodent IL-21, and it had an alignment of 83.33% with the human IL-21 nucleotide sequence and 69.93% with the amino acid sequence. The profiles of secondary structure, hydrophobicity and surface charge of tsIL-21 were also similar with those of human IL-21. The tsIL-21 expressed by the vector-transfected Huh7 cells could be identified by their different sources of antibodies against human IL-21, which were all dose-dependent. Recombinant human IL-21 could induce the change of the cytokine profiles of tree shrew spleen lymphocytes, which showed a higher expression of IL-10 and IFN-γ rather than IL-2, IL-4, IL-17, TNF-a and IL-21 during the five-day stimulation. These results indicate that tsIL-21 has a high degree of homology, structural similarity and immunological cross-reactivity with human IL-21 and also confirm the accuracy of this predicted tsIL-21CDS. The protocols utilized in this study will lead to the experimental feasibility of further IL-21-related studies in vivo.

Elevated Expression of Chemokine CXCL13 in Chronic Hepatitis B Patients Links to Immune Control during Antiviral Therapy

C–X–C-chemokine ligand 13 (CXCL13), the ligand for C–X–C chemokine receptor type 5 (CXCR5), is a major regulator of B-cell trafficking and plays an integral role in age-dependent clearance of hepatitis B virus (HBV) in the mouse model. However, the expression and function of CXCL13 in patients with chronic hepatitis B (CHB) remain unknown. By use of liver cell subpopulations isolated from CHB patients, we found that CXCL13 mRNA was abundantly expressed in Kupffer cells (KCs), but not in primary hepatocytes, liver sinusoidal endothelial cells, and hepatic stellate cells. Interestingly, KC isolated from HBV-positive liver had much higher level of CXCL13 expression than non-HBV-infected controls. And its expression was induced by toll-like receptor 3 ligand poly I:C stimulation. Moreover, intense expression of CXCL13 protein and accumulation of CD4⁺ T and B cells were evident in follicular-like structures in the liver tissue of CHB patients, which indicated its chemotactic effect on CXCR5⁺ CD4⁺ cells and B cells. Consistently, the levels of serum CXCL13 were significantly higher in the CHB patients than in healthy controls. Furthermore, CXCL13 concentration was increased in the complete response (CR) group during weeks 0–12 and did not change significantly during the course of telbivudine treatment, compared with the patients who didn’t achieve CR. In conclusion, the HBV-related increase of CXCL13 production in KC and serum CXCL13 level during telbivudine treatment might be associated with immune control of chronic HBV infection.

Effect of 48-week pegylated interferon α-2a or nucleos(t)ide analogue therapy on renal function in Chinese patients with chronic hepatitis B

Background

Controversy remains as to whether antiviral agents contribute to renal dysfunction in patients with chronic hepatitis B virus (HBV) infection. Thus, the aim of study was to analyze the changes in renal function of chronic hepatitis B (CHB) patients in response to anti-HBV therapy and the association with treatments.

Method

We performed a retrospective observational cohort study to investigate factors associated with renal function in 249 Chinese CHB patients who were treated with pegylated interferon α-2a (PEG-IFN-α-2a) or nucleos(t)ide analogues for 48 weeks. Changes of estimated glomerular filtration rate (eGFR), which was computed with both the Chronic Kidney Disease Epidemiology Collaboration and the Modification of Diet in Renal Disease formulas, were tested by repeated measures One-way analysis of variance within groups. A linear mixed effects model for repeated measures was also used to evaluate the association between baseline information and eGFR changes over time in all enrolled patients. The model considered the baseline age, sex, HBV DNA, aminotransferase, blood urea nitrogen, treatment group, time, and group-by-time interaction as fixed effects and incorporated random effects for individual subjects.

Results

The eGFR increased in patients given PEG-IFN-α-2a, decreased in patients given adefovir, but remained stable in patients given entecavir. Age and blood urea nitrogen were significant negative predictive factors for eGFR changes.

Conclusion

In real-life study, PEG-IFN-α-2a therapy in CHB patients increased eGFR, thus may associate with renoprotective effects when compared with adefovir or entecavir therapies.