Changes of costimulatory molecule CD28 on circulating CD8+ T cells correlate with disease pathogenesis of chronic hepatitis B

Exploring the causal influence of 731 immune cells on 4 different glaucoma subtypes using a two-sample mendelian randomization method

In the pathological progression of glaucoma, damage to the ocular nerves and associated tissue alterations can induce a systemic immune response, leading to the activation of various immune cells such as T cells, B cells, and macrophages. This complex process has the potential to intensify the clinical manifestations of glaucoma. Utilising Mendelian randomisation methods to identify the types and quantities of activated immune cells in different glaucoma-related lesions could provide robust evidence for the development of novel immunomodulators and immunosuppressants tailored to specific types of glaucoma, thereby facilitating personalised treatment strategies. We used five Mendelian randomisation (MR) methods-inverse variance weighted (IVW), MR-Egger, simple model, weighted median, and weighted mediation model - to assess causal relationships between immune cells and four glaucoma subtypes: neovascular glaucoma (NVG), primary open-angle glaucoma (POAG), primary closed-angle glaucoma (PACG), and normal-tension glaucoma (NTG). IVW aggregated causal estimates using Wald ratios and variance-weighted meta-analysis. MR-Egger considered horizontal pleiotropy under the InSIDE assumption. The weighted median model required ≥ 50% valid instrumental variables (IVs) for robust inference, while the weighted mediation model adjusted for SNP correlations. The simple model provided additional insight into causality. Glaucoma GWAS data were obtained from FinnGen ( https://finngen.gitbook.io/documentation/ ). Summary statistics for immune cell phenotypes (GWAS IDs: GCST90001391-GCST90002121) were obtained from the GWAS catalogue ( https://www.ebi.ac.uk/gwas/studies/GCST90002121 ). The study has identified a causal relationship between various immune cells and different types of glaucoma. It was found that 21 different types of immune cells had a causal relationship with NVG, 37 types of immune cells had a causal relationship with POAG, 40 different types of immune cells had a causal relationship with PACG, and 24 different types of immune cells had a causal relationship with NTG.

Insights into Immune Exhaustion in Chronic Hepatitis B: A Review of Checkpoint Receptor Expression

Hepatitis B, caused by the hepatitis B virus (HBV), often progresses to chronic infection, leading to severe complications, such as cirrhosis, liver failure, and hepatocellular carcinoma. Chronic HBV infection is characterized by a complex interplay between the virus and the host immune system, resulting in immune cell exhaustion, a phenomenon commonly observed in chronic viral infections and cancer. This state of exhaustion involves elevated levels of inhibitory molecules, cells, and cell surface receptors, as opposed to stimulatory counterparts. This review aims to elucidate the expression patterns of various co-inhibitory and co-stimulatory receptors on immune cells isolated from chronic hepatitis B (CHB) patients. By analyzing existing data, the review conducts comparisons between CHB patients and healthy adults, explores the differences between HBV-specific and total T cells in CHB patients, and examines variations between intrahepatic and peripheral immune cells in CHB patients. Understanding the mechanisms underlying immune exhaustion in CHB is crucial for developing novel immunotherapeutic approaches. This detailed analysis sheds light on the immune exhaustion observed in CHB and lays the groundwork for future combined immunotherapy strategies aimed at leveraging checkpoint receptors to restore immune function and improve clinical outcomes.

Innate and Adaptive Immunopathogeneses in Viral Hepatitis; Crucial Determinants of Hepatocellular Carcinoma

Viral hepatitis B (HBV) and hepatitis C (HCV) infections remain the most common risk factors for the development of hepatocellular carcinoma (HCC), and their heterogeneous distribution influences the global prevalence of this common type of liver cancer. Typical hepatitis infection elicits various immune responses within the liver microenvironment, and viral persistence induces chronic liver inflammation and carcinogenesis. HBV is directly mutagenic but can also cause low-grade liver inflammation characterized by episodes of intermittent high-grade liver inflammation, liver fibrosis, and cirrhosis, which can progress to decompensated liver disease and HCC. Equally, the absence of key innate and adaptive immune responses in chronic HCV infection dampens viral eradication and induces an exhausted and immunosuppressive liver niche that favors HCC development and progression. The objectives of this review are to (i) discuss the epidemiological pattern of HBV and HCV infections, (ii) understand the host immune response to acute and chronic viral hepatitis, and (iii) explore the link between this diseased immune environment and the development and progression of HCC in preclinical models and HCC patients.

Immune Cell Subsets Evaluation as a Predictive Tool for Hepatitis B Infection Outcome and Treatment Responsiveness

BACKGROUND

The patient's immune response is one of the major factors influencing HBV eradication or chronification, and it is thought to be responsible for the treatment success.

AIM

Our study aimed to investigate whether cellular defense mechanisms are associated with the course of HBV infection (spontaneous recovery [SR] or chronification [CHB]) and with the therapeutic approach.

PATIENTS AND METHODS

A total of 139 patients (118 with CHB, 21 SR) and 29 healthy individuals (HI) were immunophenotyped by flowcytometry. Fifty-six patients were treatment-naïve, 20 were treated with interferons and 42 with nucleoside/ nucleotide analogues.

RESULTS

Deficiency of T lymphocytes, helper-inducer (CD3+CD4+), suppressorcytotoxic (CD8+CD3+) and cytotoxic (CD8+CD11b-, CD8+CD28+) subsets, activated T cells (CD3+HLA-DR+, CD8+CD38+) and increased CD57+CD8- cells, elevated percentages of B lymphocytes and NKT cells were observed in CHB patients compared with HI. In SR patients, elevated CD8+CD11b+, NKT and activated T cells were found in comparison with controls. The higher values of T cells and their subsets in SR patients than in CHB patients reflect a recovery of cellular immunity in resolved HBV infection individuals. In both groups of treated patients, reduced T lymphocytes, CD3+CD4+ and CD8+CD38+ subsets were found in comparison with HI. Higher proportions of cytotoxic subsets were observed in treated patients compared with treatment-naïve CHB patients, more pronounced in the group with interferon therapy.

CONCLUSION

Our data demonstrate that cellular immune profiles may be of prognostic value in predicting the clinical course of HBV infection, and the determination of the therapeutic response.

Influence of Treg cells and HBV genotype on sustained response and drug resistance in the treatment with nucleoside drugs

We aimed to investigate the influence of regulatory T cells including CD4+CD25+, CD8+CD28- and hepatitis B virus (HBV) genotype on sustained virological response and tolerance of nucleoside drugs. One hundred and thirty-seven patients were enrolled. Lamivudine was administered to 84 patients. Entecavir was administered to the other 53 patients. Before treatment, biochemical tests, HBV DNA load, HBV serum level, HBV genotype, PB CD3+, CD4+, CD8+, CD4+CD25+/CD3+, and CD8+CD28-/CD3+ frequencies were measured. Based on HBV DNA loads after 4 weeks of therapy, patients were divided into response group and suboptimal response group. The lamivudine group received treatment continuously, and then patients were categorized into non-resistance group and resistance group. Compared with the suboptimal response and resistance groups for lamivudine, CD4+CD25+/CD3+ levels were higher in the response and non-resistance groups (t=4.372, P=0.046; t=7.262, P=0.017). In the non-resistance group, CD8+CD28-/CD3+ frequency was lower than in the resistance group (t=5.527, P=0.037). Virus load and hepatitis B E antigen (HBeAg)-positive rate were significantly lower than in the response and resistance group (t=2.164, P=0.038; X2=4.239, P=0.040; t=2.015, P=0.044; X2=16.2, P=0.000). Incidence of drug resistance was high in patients with virogene type C. For the virological response to entecavir, CD8+CD28-/CD3+ level was significantly lower than that of the suboptimal response group (t=6.283, P=0.036). Response and suboptimal response groups were compared in CD3+, CD4+, CD8+, CD4+CD25+/CD3+ and virus genotype, and differences were not statistically significant (P>0.05). Baseline regulatory T cells including CD4+CD25+/CD3+ and CD8+CD28-/CD3+ frequencies have a relationship with the incidence of rapid virological response and the resistance to nucleoside drugs. Patients with HBV genotype C receiving lamivudine more often underwent drug resistance. Antiviral efficacy and the resistance to lamivudine were closely correlated with baseline factors; the same cannot be found for entecavir.

Manipulation of Regulatory Cells' Responses to Treatments for Chronic Hepatitis B Virus Infection

BACKGROUND

Identification of effective treatments in hepatitis B virus (HBV) infection remains a controversial topic. Although the currently approved drugs for HBV control the disease's progression and also limit associated outcomes, these drugs may not fully eradicate HBV infection. In addition to better managing patients with chronic hepatitis B (CHB) infection, the induction of seroclearance by these drugs has been a commonly discussed topic in recent years.

OBJECTIVES

In this study, we focused on treating CHB infection via the manipulation of T cells' responses to identify possible approaches to cure CHB.

MATERIALS AND METHODS

All studies relevant to the role of cellular and humoral responses in HBV infection (especially regulatory cells) were investigated via a systematic search of different databases, including PubMed, Scopus, and Google Scholar. Considering extracted data and also our unpublished data regarding the association between regulatory cytokines and CHB, we introduced a novel approach for the induction of seroclearance.

RESULTS

Considering the increased levels of regulatory cytokines and also regulatory T cells (Tregs) during CHB, it seems that these cells are deeply involved in CHB infection. The inhibition of regulatory T cells may reverse the dysfunction of effector T cells in patients with CHB infection. In order to inhibit Tregs' responses, different types of approaches could be employed to restore the impaired function of effector T cells. The blockade of IL-10, IL-35, CTLA-4, PD-1, and TIM-3 were discussed throughout this study. Regardless of the efficacy of these methods, CHB patients may experience serious liver injuries due to the cytotoxic action of CD8+ T cells. Antiviral therapy and a decrease in HBV DNA to undetectable levels could also significantly reduce the risk of the hepatitis B flare.

CONCLUSIONS

The inhibition of Tregs is a novel therapeutic approach to cure chronically HBV infected patients. However, further studies are needed to investigate the safety and efficacy of this approach.