The correlation between T helper type 17 cells and clinical characters in Chinese paediatric patients with chronic hepatitis B

Pharmacotherapy options for managing hepatitis B in children

INTRODUCTION

To eliminate viral hepatitis by 2030, the World Health Organization (WHO) launched the first global health sector strategy on viral hepatitis, with particular focus given to hepatitis B and C in 2016. To achieve the reduction of mortality in children, it is indispensable to know which children should be treated and how to treat them.

AREA COVERED

In this article, the authors review the antiviral treatment of children with chronic hepatitis B virus (HBV) infection including antivirals available for children with chronic HBV infection.

EXPERT OPINION

The approvals of nucleos(t)ide analogues (NAs) and pegylated interferon (PEG-IFN) for children have lowered a hurdle to the initiation of antiviral treatment in children. The international guidelines use nearly the same criteria of antiviral treatment for children with chronic HBV infection, but the WHO guidelines provide a cautious stance on the antiviral treatment of children. Not only PEG-IFN but also NAs with a high genetic barrier to drug resistance should be the first-line treatment for children. In settings with limited medical resources, NAs can be the first-line treatment for children. Although the concept of an 'immune-tolerant phase' is challenged, evidence is not sufficient to recommend the treatment of HBeAg-positive immune-tolerant children.

Analysis of pathological changes and related factors in liver tissue of HBeAg-negative patients with low HBsAg levels

The relationship between pathological changes in liver tissue and the level of hepatitis B surface antigen (HBsAg) remains unclear. This study aimed to analyze the pathological changes in liver tissue and its related factors in patients with low-level HBsAg in order to provide a basis for judging the condition of these patients. A retrospective study was performed on 96 chronic hepatitis B patients with HBsAg levels < 1400 IU/ml and > 0.05 IU/ml. The histopathological examination of these patients was conducted. Univariate and multivariate analyses were used to determine risk factors for pathological changes. Among the 96 patients, 57.3% (55) had inflammatory events ≥ G2 and 33.4% (33) had fibrosis ≥ S2. HBV infection duration (p = 0.001) and splenic vein diameter (p = 0.001) were independent risk factors of liver inflammation (≥ G2) in patients with low-level HBsAg, while AST (p = 0.006) and PLT (p = 0.005) were independent risk factors of liver fibrosis (≥ S2). Moreover, HBV infection duration (p < 0.001) and spleen vein (p = 0.001) were independent factors of potential antiviral treatment. Liver inflammation and fibrosis are still common in patients with low-level HBsAg; thus, the monitoring and appropriate antiviral treatment cannot be ignored.

Association of Interleukin-17 gene polymorphisms with susceptibility to chronic hepatitis B virus infection and clearance in Iranian population

Hepatitis B virus (HBV) approximately infects 350 million people. Interleukin-17 (IL-17) as a pro-inflammatory cytokine, have been found to modulate the immune system in infectious and inflammatory diseases. Recently, the influence of genetic changes like single nucleotide polymorphisms (SNP) on expression rate and function of cytokine has been widely investigated. This study was performed to determine any possible association between four IL-17 SNPs (rs2397084, rs763780, rs2275913 and rs10484879) and chronic HBV infection. A total of 466 samples were recruited and studied including 199 chronic patients, 172 healthy controls and 95 spontaneous clearance individuals between genotype and allele frequencies. Genomic DNA was extracted from peripheral blood cells and Polymerase Chain Reaction Restriction Fragment Length Polymorphism (PCR-RFLP) was used to determine the SNPs genotypes. Genotypes frequencies for rs10484879 were 63.8% CC, 31.7% AC, 4.5% AA in chronic group, 54.7% CC, 36.6% AC, 8.7% AA in control and 63.2% CC, 33.7% AC, 5.8% AA in cleared samples. The AC genotype for rs10484879 was significantly associated with a decreased risk of HBV chronicity (Pvalue = 0.031, OR = 2.699, 95%CI: 1.097-6.639). The genotype and allele frequencies of rs2397084, rs763780 and rs2275913 did not show significant difference between chronic HBV patients and healthy controls. Indeed, there is no significant difference between clearance and chronic patient's genotypes in four SNPs. Our results suggest that IL-17A rs10484879 single nucleotide polymorphism genotype is probably associated with susceptibility to HBV chronic infection, while no significant differences in IL-17 rs2397084, rs763780 and rs227591 distribution were found between HBV patients and spontaneous clearance individuals and control participants.

Dual effect of T helper cell 17 (Th17) and regulatory T cell (Treg) in liver pathological process: From occurrence to end stage of disease

Liver disease is a complicated pathological status with acute or chronic progressions, causing a series of damages to liver and massive burden to public health and society. Th17 and Treg, two subsets of CD4⁺ T helper cells, seem to keep a subtle balance in the maintenance of organic immune homeostasis including liver. The dysfunction of Th17/Treg balance in liver has been proved associated with hepatic injury and disease. Herein, we summarized the research advance of Th17 and Treg cells in different phenotypes of liver diseases in the past decade. It is known to all that hepatic diseases start from stimulations or infections like virus, autoimmune, alcohol and so on in the early stage, which would cause inflammation. With the disease consistently existed, severe outcomes like cirrhosis and hepatocellular carcinoma appear finally. In conclusion, it is found that Th17 and Treg cells serve as an important role in the immune response imbalance of liver diseases from the beginning to the end stage. However, the effect of these two subsets of CD4⁺ T helper cells is not a stereotype. Pathological role which exacerbates the disease and protective character which inhibits damage to liver are co-existed in the effect of Th17 and Treg cells. Still, more studies should be carried out to enrich the understandings of liver disease and Th17/Treg immune balance in the future.

Role of interleukin 17 in fatty liver disease and other liver diseases

Fatty liver disease is a lipid metabolism disorder in the liver, with a variety of etiologies which result in the accumulation of fat in the liver. The pathogenesis of fatty liver disease is still unclear and symptomatic treatment is the main method. In recent years, the incidence of fatty liver disease in China is increasing year by year, and the age of onset becomes younger. Recent studies suggest that interleukin 17 (IL-17) is involved not only in the pathogenesis of various diseases, such as autoimmune diseases, inflammatory diseases, and malignant tumors, but also in fatty liver and other liver diseases through inducing insulin resistance, activating some important pathways in the liver, mediating some inflammatory factors and so on. This paper will review the role of IL-17 in fatty liver disease and other liver diseases.

Viral (hepatitis C virus, hepatitis B virus, HIV) persistence and immune homeostasis

Immune homeostasis is a host characteristic that maintains biological balance within a host. Humans have evolved many host defence mechanisms that ensure the survival of individuals upon encountering a pathogenic infection, with recovery or persistence from a viral infection being determined by both viral factors and host immunity. Chronic viral infections, such as hepatitis B virus, hepatitis C virus and HIV, often result in chronic fluctuating viraemia in the face of host cellular and humoral immune responses, which are dysregulated by multi-faceted mechanisms that are incompletely understood. This review attempts to illuminate the mechanisms involved in this process, focusing on immune homeostasis in the setting of persistent viral infection from the aspects of host defence mechanism, including interferon-stimulated genes, apolipoprotein B mRNA editing enzyme catalytic polypeptide 3 (APOBEC3), autophagy and interactions of various immune cells, cytokines and regulatory molecules.

Th17 cells in autoimmune and infectious diseases

The view of CD4 T-cell-mediated immunity as a balance between distinct lineages of Th1 and Th2 cells has changed dramatically. Identification of the IL-17 family of cytokines and of the fact that IL-23 mediates the expansion of IL-17-producing T cells uncovered a new subset of Th cells designated Th17 cells, which have emerged as a third independent T-cell subset that may play an essential role in protection against certain extracellular pathogens. Moreover, Th17 cells have been extensively analyzed because of their strong association with inflammatory disorders and autoimmune diseases. Also, they appear to be critical for controlling these disorders. Similar to Th1 and Th2 cells, Th17 cells require specific cytokines and transcription factors for their differentiation. Th17 cells have been characterized as one of the major pathogenic Th cell populations underlying the development of many autoimmune diseases, and they are enhanced and stabilized by IL-23. The characteristics of Th17 cells, cytokines, and their sources, as well as their role in infectious and autoimmune diseases, are discussed in this review.