Cytotoxic T cells and viral hepatitis

Identification of miR-29a as a novel biomarker for lumpy skin disease virus exposure in cattle

Micro RNAs (miRNAs) have been implicated in the regulation of maturation, proliferation, differentiation, and activation of immune cells. In this study, we demonstrated that miR-29a antagonizes IFN-γ production at early times post-LSDV infection in cattle. miR-29a was predicted to target upstream IFN-γ regulators, and its inhibition resulted in enhanced IFN-γ production in sensitized peripheral blood mononuclear cells (PBMCs). Further, stimulation of PBMCs with LSDV antigen exhibited lower levels of miR-29a, concomitant with a potent cell-mediated immune response (CMI), characterized by an increase in LSDV-specific CD8+ T cell counts and enhanced levels of IFN-γ, which eventually facilitated virus clearance. In addition, a few immunocompromised cattle (developed secondary LSDV infection at ~ 6 months) that failed to mount a potent cell-mediated immune response, were shown to maintain higher miR-29a levels. Furthermore, as compared to the sensitized crossbred cattle, PBMCs from sensitized Rathi (a native Indian breed) animals exhibited lower levels of miR-29a along with an increase in CD8+ T cell counts and enhanced levels of IFN-γ. Finally, we analysed that a ≥ 60% decrease in miR-29a expression levels in the PBMCs of sensitized cattle correlated with a potent CMI response. In conclusion, miR-29a expression is involved in antagonizing the IFN-γ response in LSDV-infected cattle and may serve as a novel biomarker for the acute phase of LSDV infection, as well as predicting the functionality of T cells in sensitized cattle. In addition, Rathi cattle mount a more potent CMI response against LSDV than crossbred cattle.

Three-Dimensional Structure of Novel Liver Cancer Biomarker Liver Cancer-Specific Serine Protease Inhibitor Kazal (LC-SPIK) and Its Performance in Clinical Diagnosis of Hepatocellular Carcinoma (HCC)

LC-SPIK is a liver cancer-specific isoform of Serine Protease Inhibitor Kazal and has been proposed as a new biomarker for the detection of HCC given its unique 3D structure, which differs from normal pancreatic SPIK. An ELISA technology based on its unique structure was developed to use LC-SPIK as an effective biomarker for the clinical diagnosis of HCC. AFP, the most widely used biomarker for HCC surveillance currently, suffers from poor clinical performance, especially in the detection of early-stage HCC. In one case-control study, which included 164 HCC patients and 324 controls, LC-SPIK had an AUC of 0.87 compared to only 0.70 for AFP in distinguishing HCC from liver disease controls (cirrhosis, HBV/HCV). LC-SPIK also performed significantly better than AFP for the 81 patients with early-stage HCC (BCLC stage 0 and A), with an AUC of 0.85 compared to only 0.61 for AFP. Cirrhosis is the major risk factor for HCC; about 80% of patients with newly diagnosed HCC have preexisting cirrhosis. LC-SPIK's clinical performance was also studied in HCC patients with viral and non-viral cirrhosis, including cirrhosis caused by metabolic dysfunction-associated steatotic liver disease (MASLD) and alcoholic liver disease (ALD). In a total of 163 viral cirrhosis patients with 93 HCC patients (50 early-stage), LC-SPIK had an AUC of 0.85, while AFP had an AUC of 0.70. For patients with early-stage HCC, LC-SPIK had a similar AUC of 0.83, while AFP had an AUC of only 0.60. For 120 patients with nonviral cirrhosis, including 62 HCC (23 early-stage) patients, LC-SPIK had an AUC of 0.84, while AFP had an AUC of only 0.72. For the 23 patients with early-stage HCC, LC-SPIK had a similar AUC of 0.83, while the AUC for AFP decreased to 0.65. All these results suggest that LC-SPIK exhibits significantly better performance in the detection of HCC than AFP in all etiologies of liver diseases. In addition, LC-SPIK accurately detected the presence of HCC in 71-91% of HCC patients with false-negative AFP test results in viral-associated HCC and non-viral-associated HCC.

AAV Immunotoxicity: Implications in Anti-HBV Gene Therapy

Hepatitis B virus (HBV) has afflicted humankind for decades and there is still no treatment that can clear the infection. The development of recombinant adeno-associated virus (rAAV)-based gene therapy for HBV infection has become important in recent years and research has made exciting leaps. Initial studies, mainly using mouse models, showed that rAAVs are non-toxic and induce minimal immune responses. However, several later studies demonstrated rAAV toxicity, which is inextricably associated with immunogenicity. This is a major setback for the progression of rAAV-based therapies toward clinical application. Research aimed at understanding the mechanisms behind rAAV immunity and toxicity has contributed significantly to the inception of approaches to overcoming these challenges. The target tissue, the features of the vector, and the vector dose are some of the determinants of AAV toxicity, with the latter being associated with the most severe adverse events. This review discusses our current understanding of rAAV immunogenicity, toxicity, and approaches to overcoming these hurdles. How this information and current knowledge about HBV biology and immunity can be harnessed in the efforts to design safe and effective anti-HBV rAAVs is discussed.

Antigen Recognition and Immune Response to Acute and Chronic Hepatitis B Virus Infection

The antigen recognition and immune response to acute and chronic hepatitis B virus (HBV) infections are the result of both the innate and adaptive immune response. The innate immune response comprises Dendritic Cells (DCs), which served as professional antigen-presenting cells and a bridge between innate and adaptive immunity, Kupffer cells and inflammatory monocytes for the continuous inflammation of hepatocyte, neutrophils for hepatic tissue damage due to acute inflammation, type I interferons (IFN), which induce an antiviral state on infected cells, directs natural killer (NK) cells to kill virally infected cells, reduces the population of infected cells, and promotes the effective maturation and site recruitment of adaptive immunity through the production of pro-inflammatory cytokines and chemokines. Through stimulating B cells, T-helper, and cytotoxic T cells, the adaptive immune system also protects against hepatitis B infection. During HBV infection, a network of cell types that can either play protective or harmful functions creates the anti-viral adaptive immune response. These many elements, such as ‎Cluster of differentiation four (CD4) T cells (traditionally known as helper T cells), are potent cytokine producers and necessary for the effective maturation of effector cytotoxic cluster of differentiation eight (CD8) T cells and B cell antibody production. By cytolytic and non-cytolytic processes, CD8 T cells are able to eliminate HBV-infected hepatocytes and directly detect virus-infected cells, and circulating CD4+ CD25+ regulatory T cells for the modulation of immune system. In order to avoid reinfection, B cells can produce antibodies that destroy free viral particles. Moreover, by presenting HBV antigens to helper T cells, B cells may also influence how well these cells operate.

Act Early and at the Right Location: SARS-CoV-2 T Cell Kinetics and Tissue Localization

The emergence of new SARS-CoV-2 lineages able to escape antibodies elicited by infection or vaccination based on the Spike protein of the Wuhan isolates has reduced the ability of Spike-specific antibodies to protect previously infected or vaccinated individuals from infection. Therefore, the role played by T cells in the containment of viral replication and spread after infection has taken a more central stage. In this brief review, we will discuss the role played by T cells in the protection from COVID-19, with a particular emphasis on the kinetics of the T cell response and its localization at the site of primary infection.

Prevention of HBV Reactivation in Hemato-Oncologic Setting during COVID-19

Onco-hematologic patients are highly susceptible to SARS-CoV-2 infection and, once infected, frequently develop COVID-19 due to the immunosuppression caused by tumor growth, chemotherapy and immunosuppressive therapy. In addition, COVID-19 has also been recognized as a further cause of HBV reactivation, since its treatment includes the administration of corticosteroids and some immunosuppressive drugs. Consequently, onco-hematologic patients should undergo SARS-CoV-2 vaccination and comply with the rules imposed by lockdowns or other forms of social distancing. Furthermore, onco-hematologic facilities should be adapted to new needs and provided with numerically adequate health personnel vaccinated against SARS-CoV-2 infection. Onco-hematologic patients, both HBsAg-positive and HBsAg-negative/HBcAb-positive, may develop HBV reactivation, made possible by the support of the covalently closed circular DNA (cccDNA) persisting in the hepatocytic nuclei of patients with an ongoing or past HBV infection. This occurrence must be prevented by administering high genetic barrier HBV nucleo(t)side analogues before and throughout the antineoplastic treatment, and then during a long-term post-treatment follow up. The prevention of HBV reactivation during the SARS-CoV-2 pandemic is the topic of this narrative review.

Maternal Immune Activation and Dietary Soy Isoflavone Supplementation Influence Pig Immune Function but not Muscle Fiber Formation

The goals of this study were to determine the impact of maternal PRRSV infection on offspring muscle and immune development and the potential of dietary soy isoflavones to mitigate those effects. Thirteen first-parity gilts (“gilts”) were randomly allotted into one of three treatments: not infected and fed a diet devoid of isoflavones (CON), infected with porcine reproductive and respiratory syndrome virus (PRRSV) and fed the control diet (POS) or that supplemented with 1,500 mg/kg soy-derived isoflavones (ISF). Gilts were inoculated with PRRSV intranasally on gestational day (GD) 70. After farrowing (GD 114 ± 2), 1-2 offspring (“pigs”) closest to the average litter weight were selected either at birth (3 ± 2 d of age) or weaning (21 ±2 d of age) to determine body, muscle, and organ weights as well as muscle cell number and size. Four weaned pigs of average body weight within each litter were selected for postnatal immune challenge. At PND 52, pigs were injected with 5 µg/kg BW lipopolysaccharide (LPS) intraperitoneally. Serum was collected at 0, 4, and 8 h following LPS administration to analyze tumor necrosis factor alpha (TNF-α). At PND 59, pigs were administered a novel vaccine to elicit an adaptive immune response. At PND 59, 66, and 73, peripheral blood mononuclear cells were isolated and T-cell populations determined by flow cytometry. Both POS and ISF pigs exhibited persistent PRRSV infections throughout the study (PND 1-73). At PND 3, whole body, muscle, and organ weights were not different (P > 0.22) between groups, with the exception of relative liver weight, which was increased (P < 0.05) in POS compared with CON pigs. At PND 21, ISF pigs had reduced (P ≤ 0.05) whole body and muscle weights, but greater (P < 0.05) kidney weight compared with CON, and greater (P < 0.05) relative liver weight compared with CON and POS. Muscle fiber number and size were not different (P > 0.39) between groups at birth or weaning. After LPS administration, TNF-α was greatest in ISF pigs (P < 0.05) at both 0 and 8 h post-challenge. At the peak time-point of 4 h post-challenge, ISF pigs had the greatest concentration of TNF-α and CON pigs had the lowest, with POS pigs being intermediate (P = 0.01). After vaccination, ISF offspring had shifts in T-cell populations indicating an impaired immune response. These data indicate that maternal PRRSV infection may impact offspring organ growth and immune function, particularly when the dam is supplemented with isoflavones.

The association between hepatitis C virus infection and renal cell cancer, prostate cancer, and bladder cancer: a systematic review and meta-analysis

To update the current evidence on whether hepatitis C virus (HCV) infection represents a possible risk factor for renal cell cancer (RCC), prostate cancer (PCa), and bladder cancer (BC). We searched the literature on Pubmed, Web of Science, and Embases before April 2021. A systematic review and meta-analysis were performed. Finally, we extracted 12 studies based on the eligible criteria. Across 11 studies for HCV and RCC, the incorporated RR was 1.28 (95% CI 1.05–1.55), which meant that participants with HCV infection were associated with higher RCC risk. The pooled RR in hazard ratio (HR) subgroup (HR 1.59, 95% CI 1.22–2.08), cohort studies subgroup (RR 1.47, 95% CI 1.18–1.82), and North America subgroup (RR 1.71, 95% CI 1.40–2.09) detected a stronger association between HCV and RCC risk. Although an inverse association was seen for PCa (RR 0.75, 95% CI 0.54–1.03) across seven studies, it was not statistically significant (P = 0.075). There was no significant association between HCV and BC with an incorporated RR of 0.92 (95% CI, 0.82–1.03) across five studies. Our study demonstrated that HCV infection was significantly associated with increased RCC risk. There appeared to be an inverse association for HCV in PCa risk but not statistically significant. No significant association was found between HCV and BC risk. Prospective, large-scale, and well-designed cohort studies are required to validate the association between HCV and RCC, and to investigate the role of HCV on PCa.

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.

HMGB1: An overview of its roles in the pathogenesis of liver disease

High-mobility group box 1 (HMGB1) is an abundant architectural chromosomal protein that has multiple biologic functions: gene transcription, DNA replication, DNA-damage repair, and cell signaling for inflammation. HMGB1 can be released passively by necrotic cells or secreted actively by activated immune cells into the extracellular milieu after injury. Extracellular HMGB1 acts as a damage-associated molecular pattern to initiate the innate inflammatory response to infection and injury by communicating with neighboring cells through binding to specific cell-surface receptors, including Toll-like receptors (TLRs) and the receptor for advanced glycation end products (RAGE). Numerous studies have suggested HMGB1 to act as a key protein mediating the pathogenesis of chronic and acute liver diseases, including nonalcoholic fatty liver disease, hepatocellular carcinoma, and hepatic ischemia/reperfusion injury. Here, we provide a detailed review that focuses on the role of HMGB1 and HMGB1-mediated inflammatory signaling pathways in the pathogenesis of liver diseases.

Alcohol Intake and Mortality in Patients With Chronic Viral Hepatitis: A Nationwide Cohort Study

INTRODUCTION

We evaluated the association between alcohol intake and all-cause and cause-specific mortality in subjects with chronic viral hepatitis, using nationwide population-based cohort study.

METHODS

A total of 364,361 men and women aged 40-84 years who underwent health screening examination between January 2002 and December 2013 that included assessment of frequency and amount of alcohol consumption were assessed for all-cause and cause-specific mortality.

RESULTS

In participants without chronic viral hepatitis, the fully adjusted hazard ratios (HRs) for all-cause mortality comparing light, moderate, and heavy drinkers with nondrinkers were 0.92 (95% confidence interval [CI] 0.87-0.98), 1.08 (95% CI 1.01-1.16), and 1.51 (95% CI 1.33-1.72), respectively. In participants with chronic viral hepatitis, the corresponding HRs were 1.19 (95% CI 1.05-1.36), 1.23 (95% CI 1.06-1.43), and 1.69 (95% CI 1.28-2.24), respectively (P value for alcohol intake by chronic viral hepatitis interaction <0.001). Compared with participants without chronic viral hepatitis, those with chronic viral hepatitis had substantially elevated liver cancer or liver disease (HR 10.85, 95% CI 9.74-12.09) and extrahepatic cancer mortality (HR 1.37, 95% CI 1.26-1.49). In patients with chronic viral hepatitis, the high mortality due to liver cancer or liver disease and the positive association of alcohol intake with liver cancer or liver disease mortality explained the positive association of alcohol intake with all-cause mortality.

DISCUSSION

Even light to moderate alcohol intake was associated with increased all-cause mortality in individuals with chronic viral hepatitis. Clinicians and public health campaigns should advise against any amount of alcohol intake in individuals with chronic viral hepatitis.

Incidence of extrahepatic cancers among individuals with chronic hepatitis B or C virus infection: A nationwide cohort study

This study examined the association between chronic HBV or HCV infection and the risk of extrahepatic cancers. A total of 537 103 adults aged ≥20 years without history of cancer were identified from the Korean National Health Insurance Service-National Sample Cohort between 2003 and 2013. The difference in cancer incidence was compared between those with and without chronic HBV or HCV infection. During 3 854 130 person-years of follow-up (median follow-up: 8.0 years), 19 089 participants developed cancer. After adjusting for sex, body mass index, smoking, drinking, income percentile, residential area and comorbidities, hazard ratios (HRs) for incident extrahepatic cancer were significantly higher in participants with chronic HBV infection (HR: 1.27, 95% confidence interval [CI]: 1.20-1.35), HCV infection (HR: 1.31, 95% CI: 1.16-1.48) or HBV/HCV dual infection (HR: 1.41, 95% CI: 1.31-1.72) compared to participants without HBV or HCV infection. In chronic HBV infection, the cancer risk was higher for haematologic malignancy [HR (95% CI) = 2.46 (1.92-3.15)], gallbladder [1.55 (1.05-2.29)], pancreas [1.52 (1.07-2.15)], stomach [1.39 (1.22-1.58)], lung [1.27 (1.04-1.55)], colorectum [1.21 (1.03-1.42)] and thyroid cancer [1.20 (1.05-1.36)]. In chronic HCV infection, the cancer risk was higher for testis [10.34 (1.35-79.78)], gallbladder [2.90 (1.62-5.18)], prostate [2.51 (1.65-3.82)] and thyroid cancer [1.46 (1.10-1.93)]. In conclusion, chronic HBV or HCV infection was not only associated with an increased risk of liver cancer, but also associated with an increased risk of multiple extrahepatic cancers.

Biological features of hepatitis B virus strains associated with fulminant hepatitis

Accumulating evidence suggests that hepatitis B virus (HBV) biological features may influence the course and clinical manifestations of infection and possibly the development of fulminant hepatitis (FH). Since HBV is not a cytocidal virus, virus-induced liver damage results from an interplay between the virus replication and the host's defense. Therefore, viral factors contributing to enhanced replication, induction of a stronger immune attack or apoptosis of hepatocytes could be crucial in development of FH. Numerous mutations in basal core promoter, pre-C, C and S regions of the HBV genome contribute to development of FH by different mechanisms, including enhanced viral replication, the loss of a decoy for immune response, unbalanced expression of viral proteins and retention of unprocessed cytotoxic proteins in hepatocytes.

Association between the rs9131 and rs3806792 polymorphisms of the CXCL2 gene and the risk of HBV-related hepatocellular carcinoma in a Guangxi population

Background

Genetic polymorphisms in the CXCL2 may participate in the progress of HBV‐related HCC. However, no researches have evaluated the association between them.

Methods

To figure out the effects of CXCL2 gene polymorphisms on the risk of HBV‐related HCC, two major variants of CXCL2 and their association with chronic hepatitis B (CHB), HBV‐related liver cirrhosis (LC), and HCC were conducted in a Guangxi population. CXCL2 polymorphisms rs9131 and rs3806792 were examined in 147 healthy controls, 138 CHB patients, 137 HBV‐related LC patients, and 150 HBV‐related HCC patients, using the SNaPshot™ genotyping technique.

Results

No significant differences were found regarding the CXCL2 rs9131 and rs3806792 polymorphisms among the case groups (including CHB, LC, and HCC) and the healthy controls, no matter in comparisons of alleles, genotypes, or haplotypes. Similar insignificant results were also observed when subgroup analyses were performed in different gender. However, when compared the frequencies of allele and genotype in the healthy individuals of our research and those from the 1000 Genomes Project, CC and C for rs9131, and TT and T for rs3806792 of CXCL2 in our healthy controls were only similar with those in Han Chinese in Beijing, but significantly higher than other ethnicities; this indicates that these two polymorphisms of CXCL2 may be not associated with the pathogenesis of HBV‐related HCC in Chinese population, but may play a role in other ethnicities.

Conclusion

Our observation suggests that SNPs rs9131 and rs3806792 of CXCL2 gene might not contribute to the development of CHB, HBV‐related LC, and HCC in a Guangxi population.

Role of alcohol in pathogenesis of hepatitis B virus infection

Hepatitis B virus (HBV) and alcohol abuse often contribute to the development of end-stage liver disease. Alcohol abuse not only causes rapid progression of liver disease in HBV infected patients but also allows HBV to persist chronically. Importantly, the mechanism by which alcohol promotes the progression of HBV-associated liver disease are not completely understood. Potential mechanisms include a suppressed immune response, oxidative stress, endoplasmic reticulum and Golgi apparatus stresses, and increased HBV replication. Certainly, more research is necessary to gain a better understanding of these mechanisms such that treatment(s) to prevent rapid liver disease progression in alcohol-abusing HBV patients could be developed. In this review, we discuss the aforementioned factors for the higher risk of liver diseases in alcohol-induced HBV pathogenies and suggest the areas for future studies in this field.

PCAF fine-tunes hepatic metabolic syndrome, inflammatory disease, and cancer

The P300/CBP‐associating factor (PCAF), a histone acetyltransferase, is involved in metabolic and pathogenic diseases, particularly of the liver. The effects of PCAF on fine‐tuning liver diseases are extremely complex and vary according to different pathological conditions. This enzyme has dichotomous functions, depending on differently modified sites, which regulate the activities of various enzymes, metabolic functions, and gene expression. Here, we summarize the most recent findings on the functions and targets of PCAF in various metabolic and immunological processes in the liver and review these new discoveries and models of PCAF biology in three areas: hepatic metabolic syndrome, inflammatory disease, and cancer. Finally, we discuss the potential implications of these findings for therapeutic interventions in liver diseases.

Proliferation of primary human hepatocytes and prevention of hepatitis B virus reinfection efficiently deplete nuclear cccDNA in vivo

OBJECTIVE

The stability of the covalently closed circular DNA (cccDNA) in nuclei of non-dividing hepatocytes represents a key determinant of HBV persistence. Contrarily, studies with animal hepadnaviruses indicated that hepatocyte turnover can reduce cccDNA loads but knowledge on the proliferative capacity of HBV-infected primary human hepatocytes (PHHs) in vivo and the fate of cccDNA in dividing PHHs is still lacking. This study aimed to determine the impact of human hepatocyte division on cccDNA stability in vivo.

METHODS

PHH proliferation was triggered by serially transplanting hepatocytes from HBV-infected humanised mice into naïve recipients. Cell proliferation and virological changes were assessed by quantitative PCR, immunofluorescence and RNA in situ hybridisation. Viral integrations were analysed by gel separation and deep sequencing.

RESULTS

PHH proliferation strongly reduced all infection markers, including cccDNA (median 2.4 log/PHH). Remarkably, cell division appeared to cause cccDNA dilution among daughter cells and intrahepatic cccDNA loss. Nevertheless, HBV survived in sporadic non-proliferating human hepatocytes, so that virological markers rebounded as hepatocyte expansion relented. This was due to reinfection of quiescent PHHs since treatment with the entry inhibitor myrcludex-B or nucleoside analogues blocked viral spread and intrahepatic cccDNA accumulation. Viral integrations were detected both in donors and recipient mice but did not appear to contribute to antigen production.

CONCLUSIONS

We demonstrate that human hepatocyte division even without involvement of cytolytic mechanisms triggers substantial cccDNA loss. This process may be fundamental to resolve self-limiting acute infection and should be considered in future therapeutic interventions along with entry inhibition strategies.

Association of -319 C/T and +49 A/G polymorphisms of CTLA-4 gene in patients with hepatitis C virus infection

INTRODUCTION AND OBJECTIVE

Molecular changes in the CTLA-4 gene can modify the ability to control T lymphocyte proliferation, and promote the persistence or elimination of the hepatitis C virus (HCV). We aimed to investigate the frequency and association of -319 C/T and +49 A/G polymorphism in the CTLA-4 gene in patients infected with HCV.

METHODS

The CTLA-4 gene polymorphisms (-319 C/T in the promoter region, and +49 A/G in exon 1) were analysed by T-ARMS-PCR in 420 individuals, including 205 chronic HCV infected patients and 215 healthy subjects.

RESULTS

We found a positive association of +49G allele with HCV infection (OR 1.48; 95% CI 1.09-2.02; p=.02), and with males (OR 1.80; 95% CI 1.16-2.79; p=.02), both in chronic disease (without cirrhosis). Also, significant differences in +49 A/G genotypes distribution between HCV infected patients and healthy subjects were shown in a dominant genetic model (GG+GA versus AA; OR 1.57; 95% CI 1.05-2.33; p=.04). No significant differences were observed in the -319 C/T polymorphism between HCV infected patients and healthy subjects. Moreover, -319C/+49G haplotype confers susceptibility to HCV genotype 3 infection (OR 10.68; 95% CI 1.17-96.97; p=.04).

CONCLUSIONS

The +49G allele confers susceptibility to HCV infection and with male gender, both in chronic disease. In addition, the -319C/+49G haplotype confers susceptibility to HCV genotype 3 infection. Our results support an important role of the -319 C/T and +49 A/G polymorphisms in HCV infection.

Hepatitis C and Risk of Nonhepatic Malignancies

Epidemiologic studies show an increased risk of mortality among hepatitis C virus (HCV)-infected individuals compared with uninfected individuals from hepatic and nonhepatic causes. This article reviews the biologic plausibility of and epidemiologic evidence for the association between HCV and five extrahepatic malignancies: cholangiocarcinoma (CCA), pancreatic adenocarcinoma, papillary thyroid cancer, oral squamous cell cancer, and renal/kidney cancer. There is sufficient evidence to suggest that HCV is associated with intrahepatic CCA. The evidence for the link between HCV and pancreatic adenocarcinoma, oral squamous cell cancer, and renal/kidney cancer is compelling but requires further study. Based on available studies, there is no significant association between HCV, extrahepatic CCA, and papillary thyroid cancer.

Human Leukocyte Antigen (HLA) and Immune Regulation: How Do Classical and Non-Classical HLA Alleles Modulate Immune Response to Human Immunodeficiency Virus and Hepatitis C Virus Infections?

The genetic factors associated with susceptibility or resistance to viral infections are likely to involve a sophisticated array of immune response. These genetic elements may modulate other biological factors that account for significant influence on the gene expression and/or protein function in the host. Among them, the role of the major histocompatibility complex in viral pathogenesis in particular human immunodeficiency virus (HIV) and hepatitis C virus (HCV), is very well documented. We, recently, added a novel insight into the field by identifying the molecular mechanism associated with the protective role of human leukocyte antigen (HLA)-B27/B57 CD8⁺ T cells in the context of HIV-1 infection and why these alleles act as a double-edged sword protecting against viral infections but predisposing the host to autoimmune diseases. The focus of this review will be reexamining the role of classical and non-classical HLA alleles, including class Ia (HLA-A, -B, -C), class Ib (HLA-E, -F, -G, -H), and class II (HLA-DR, -DQ, -DM, and -DP) in immune regulation and viral pathogenesis (e.g., HIV and HCV). To our knowledge, this is the very first review of its kind to comprehensively analyze the role of these molecules in immune regulation associated with chronic viral infections.

The Role of cccDNA in HBV Maintenance

Chronic hepatitis B virus (HBV) infection continues to be a major health burden worldwide; it can cause various degrees of liver damage and is strongly associated with the development of liver cirrhosis and hepatocellular carcinoma. The molecular mechanisms determining HBV persistence are not fully understood, but these appear to be multifactorial and the unique replication strategy employed by HBV enables its maintenance in infected hepatocytes. Both the stability of the HBV genome, which forms a stable minichromosome, the covalently closed circular DNA (cccDNA) in the hepatocyte nucleus, and the inability of the immune system to resolve chronic HBV infection are believed to be key mechanisms of HBV chronicity. Since a true cure of HBV requires clearance of intranuclear cccDNA from infected hepatocytes, understanding the mechanisms involved in cccDNA biogenesis, regulation and stability is mandatory to achieve HBV eradication. This review will summarize the state of knowledge on these mechanisms including the impact of current treatments on the cccDNA stability and activity. We will focus on events challenging cccDNA persistence in dividing hepatocytes.

Hepatitis C Virus and Nonliver Solid Cancers: Is There an Association between HCV and Cancers of the Pancreas, Thyroid, Kidney, Oral Cavity, Breast, Lung, and Gastrointestinal Tract?

Hepatitis C virus (HCV) is known for its oncogenic potential and has been found to be associated with hepatocellular carcinoma (HCC) and non-Hodgkin lymphoma. It has also been postulated that HCV may play a role in the development of other extrahepatic solid tumors of other organs of the body since it has been isolated from the vessel wall, kidney, and oral mucosa. In this article, we have reviewed epidemiological studies that have been done to look into the relationship of HCV with nonliver solid cancers of the pancreas, thyroid, renal, oral cavity, breast, and lung and nonpancreatic gastrointestinal cancers. Based on this review, HCV might be associated with an increased risk of renal cell and lung cancers.

Protective efficacy and hepatitis B virus clearance in mice enhanced by cell-mediated immunity with novel prime-boost regimens

In this study, anti-hepatitis B virus (HBV) immunity was evaluated in mice using several regimens of the HBV recombinant protein vaccine HBSS1 that expressed in CHO cells containing S (1-223 aa) and preS1 (21-47 aa) and recombinant adenovirus rAdSS1 vaccine. Further, the protective efficacy of these vaccine regimens was studied in a mouse model. High titres of antigen-specific antibodies and neutralizing activity were elicited in mice after vaccination. However, robust multi-antigen (preS1 and S)-specific cell-mediated immunity (CMI) was only detected in mice primed with HBSS1 and boosted with rAdSS1. Moreover, functional T-cell responses with high levels of cytokines and antigen-specific cytotoxic T-cell responses (CD107a⁺ CD8⁺ ) were also detected in the mice. Rapid clearance of hepatitis B surface antigen and HBV DNA in blood and significantly decreased hepatitis B envelope antigen levels were observed in mice immunized with the heterogeneous prime-boost vaccine after hepatitis B virus challenge by hydrodynamic injection (HI) of pCS-HBV1.3. The clearance of HBV correlated well with antigen-specific CMI (Th1 and CTL responses) and cytokine profiles (IFN-γ, TNF-α, IL-2) elicited by vaccination. Taken together, our results might contribute to the development of new human HBV vaccines and a better understanding of the mechanisms underlying immune protection and clearance of hepatitis B virus infection.

The Impact of Chemotherapy on Hepatitis B Antibody Titer in Patients with Hematological Malignancies

Objective:

To investigate the influence of chemotherapy (CT) on HBsAb titer in patients receiving CT due to hematological malignancy.

Materials and Methods:

The data of 75 patients who received CT with the diagnosis of various hematological malignancies and who had serum HBsAb levels measured prior to and after the cessation of CT were evaluated retrospectively.

Results:

The median age of the patients was 52 years (range: 16-78) with 49 (65%) males and 26 (35%) females. Median HBsAb titer decreased significantly after CT compared to the pre-CT median HBsAb titer [68 (range: 0-1000) vs. 100 (range: 6.2-1000)] (p=0.001). In subgroup analysis, median HBsAb titer decreased significantly after CT in acute leukemia patients [110 (range: 6.2-1000) vs. 67.8 (range: 0-1000)] (p=0.003) and in patients receiving intensive CT [97.2 (range: 6.2-1000) vs. 71 (range: 0-1000)] (p=0.036). The decrease in median HBsAb titer was significant in male patients (p<0.001). HBsAb became negative after CT in 9 patients who were HBcAb-negative and had lower pre-CT HBsAb levels.

Conclusion:

HBsAb decreased after CT, especially in acute leukemia and male patients, and in patients receiving intensive CT.

Hepatitis C infection and renal cell carcinoma: A systematic review and meta-analysis

AIM

To investigate the association between hepatitis C virus (HCV) infection and risk of renal cell carcinoma (RCC).

METHODS

A literature search was performed from inception until February 2016. Studies that reported relative risks, odd ratios, hazard ratios or standardized incidence ratio comparing the risk of RCC among HCV-infected participants vs those without HCV infection were included. Participants without HCV infection were used as comparators. Pooled odds ratios and 95%CI were calculated using a random-effect, generic inverse variance method.

RESULTS

Seven observational studies were with 196826 patients were included in the analysis to assess the risk of RCC in patients with HCV. A significantly increased risk of RCC among participants with HCV infection was found with a pooled RR of 1.86 (95%CI: 1.11-3.11). The association between RCC and HCV was marginally insignificant after a sensitivity analysis limited only to studies with adjusted analysis, with a pooled RR of 1.50 (95%CI: 0.93-2.42).

CONCLUSION

Our study demonstrated a potential association between HCV infection and RCC. Further studies of RCC surveillance in patients with HCV are required.

Natural Killer Group 2A Expressed on Both Peripheral CD3-CD56+NK Cells and CD3+CD8+T Cells Plays a Pivotal Negative Regulatory Role in the Progression of Hepatitis B Virus-Related Acute-on-Chronic Liver Failure

To explore the role of surface receptors natural killer group 2A (NKG2A) and natural killer group 2D (NKG2D) on CD3⁺CD8⁺T cells and CD3^-CD56⁺NK cells in the progression of hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF), we measured the expression of NKG2A and NKG2D on the surface of these 2 types of circulating cells by flow cytometry in 3 groups. One group consists of 36 patients with chronic hepatitis B (CHB), another one consists of 22 patients with HBV-related ACLF, and the last one has 12 normal controls (NC). The experimental result indicated that there was no significant difference in the proportion of CD3⁺CD8⁺T cells in total lymphocytes between the 3 groups. However, the percentage of CD3^-CD56⁺NK cells in ACLF group was evidently higher than that in the CHB group (P < 0.05). In addition, the expression of NKG2D on CD3⁺CD8⁺T cells in the ACLF group was significantly lower than that in the CHB group (P < 0.05), but there were no statistically significant differences in its percentages on CD3^-CD56⁺NK cells between the 3 groups. The expression of NKG2A on CD3⁺CD8⁺T cells in the ACLF group was significantly higher than that in the NC group (P < 0.05), and on NK cells was significantly higher than that in the CHB group (P < 0.05) and NC group (P < 0.01). The increase in ratios of NKG2A to NKG2D on CD3⁺CD8⁺T cells and CD3^-CD56⁺NK cells in the ACLF group was significantly more than that in the CHB group and NC group. The results indicate that the imbalance between NKG2A and NKG2D may contribute to the progression of HBV-related ACLF mediated by CD3^-CD56⁺NK cells and CD3⁺CD8⁺T cells. Compared with NKG2D, NKG2A expressed on both peripheral CD3^-CD56⁺NK cells and CD3⁺CD8⁺T cells plays a more pivotal negative regulatory role in the progression of HBV-related ACLF.

New horizon for radical cure of chronic hepatitis B virus infection

About 250 to 350 million people worldwide are chronically infected with hepatitis B virus (HBV), and about 700000 patients per year die of HBV-related cirrhosis or hepatocellular carcinoma (HCC). Several anti-viral agents, such as interferon and nucleos(t)ide analogues (NAs), have been used to treat this disease. NAs especially have been shown to strongly suppress HBV replication, slowing the progression to cirrhosis and the development of HCC. However, reactivation of HBV replication often occurs after cessation of treatment, because NAs alone cannot completely remove covalently-closed circular DNA (cccDNA), the template of HBV replication, from the nuclei of hepatocytes. Anti-HBV immune responses, in conjunction with interferon-γ and tumor necrosis factor-α, were found to eliminate cccDNA, but complete eradication of cccDNA by immune response alone is difficult, as shown in patients who recover from acute HBV infection but often show long-term persistence of small amounts of HBV-DNA in the blood. Several new drugs interfering with the life cycle of HBV in hepatocytes have been developed, with drugs targeting cccDNA theoretically the most effective for radical cure of chronic HBV infection. However, the safety of these drugs should be extensively examined before application to patients, and combinations of several approaches may be necessary for radical cure of chronic HBV infection.

Fatal fulminant hepatitis caused by infection with subgenotype A1 hepatitis B virus with C1766T/T1768A core promoter mutations

Adults initially infected with the hepatitis B virus develop various types of hepatitis ranging from asymptomatic to fulminant, and the clinical course of infection is influenced by a variety of host and viral factors. The viral risk factors associated with fulminant hepatitis reportedly include subgenotype B1, negative HBe antigen, and mutations in the precore and core promoter regions. Here, we present a case of fatal fulminant hepatitis caused by infection with subgenotype A1 hepatitis B virus with C1766T/T1768A double mutations in the core promoter region. A 53-year-old man was hospitalized with acute hepatitis B. Immediately after admission, entecavir was administered. However, his condition deteriorated, developing into fulminant hepatitis 2 days later. Artificial extracorporeal liver support therapy with plasma exchange (PE) and hemodiafiltration (HDF) were started. At one time point, the severity of hepatic encephalopathy decreased from grade II to grade 0, and the prothrombin time also improved, increasing from 11 to 73 %. However, the total bilirubin levels remained at or above 20 mg/dL and blood creatinine levels gradually increased. HDF was restarted, and therapies such as bilirubin adsorption and PE were administered. However, neither hepatic nor renal failure was alleviated, and the patient died 78 days after admission.

Adaptive immunity in HBV infection

During hepatitis B virus (HBV) infection, the presence of HBV-specific antibody producing B cells and functional HBV-specific T cells (with helper or cytotoxic effects) ultimately determines HBV infection outcome. In this review, in addition to summarizing the present state of knowledge of HBV-adaptive immunity, we will highlight controversies and uncertainties concerning the HBV-specific B and T lymphocyte response, and propose future directions for research aimed at the generation of more efficient immunotherapeutic strategies.

Risk factors for cytomegalovirus DNAemia following haploidentical stem cell transplantation and its association with host hepatitis B virus serostatus

BACKGROUND

The risk factors associated with CMV DNAemia are not well known after haploidentical stem cell transplantation (SCT).

OBJECTIVES

This study investigated the risk factors and prognosis for CMV DNAemia among CMV seromatched donors and recipients (D+/R+).

STUDY DESIGN

A retrospective study of patients undergoing haploidentical stem cell transplantation (SCT) between January 2010 and January 2012 was conducted. Cox regression analysis was performed to identify the risk factors for CMV DNAemia. These possible factors included recipient/donor age, recipient/donor gender, gender disparity, recipient HBsAg serostatus, diagnosis, risk stratification, anti-thymocyte globulin (ATG) dose (6mg/kg,10mg/kg), early neutrophil engraftment (≤12 days, >12 days), absolute lymphocyte count on day 30 (ALC30) and the occurrence of acute GVHD before CMV DNAemia.

RESULTS

The total number of patients was 248 with median age of 31 years (range, 14-56). The cumulative incidence of CMV DNAemia (146/248) was 59.5%. CMV DNAemia was first detected after a median of +35 days (range,12-82). Seventeen patients (17/146, 11.6%) developed CMV disease. Multivariate analysis identified HBsAg seropositivity (P=0.002, hazard ratio (HR)=1.833; 95%CI=1.257-2.673) and the occurrence of acute GVHD before CMV DNAemia (P=0.014; HR=1.520; 95%CI=1.088-2.124) as risk factors for CMV DNAemia. CMV DNAemia was associated with subsequent II-IV acute graft-versus-host disease (GVHD) (P=0.014), III-IV aGVHD (P=0.013) and chronic GVHD (P=0.008). Totally, CMV DNAemia was found to be a poor prognostic factor in terms of non-relapse mortality (NRM) (P=0.003, HR=2.730; 95%CI=1.406-5.197), and overall survival (OS) (P=0.045, HR=1.654; 95%CI=1.012-2.701).

CONCLUSIONS

Our data showed HBsAg seropositivity was associated with an increased risk of cytomegalovirus DNAemia. Detection of CMV DNAemia proved to be a poor prognostic factor for haploidentical patients.

A novel dendritic-cell-targeting DNA vaccine for hepatitis B induces T cell and humoral immune responses and potentiates the antivirus activity in HBV transgenic mice

Strategies for inducing an effective immune response following vaccination have focused on targeting antigens to dendritic cells (DCs) through the DC-specific surface molecule DEC-205. The immunogenicity and efficacy of DNA vaccination can also be enhanced by fusing the encoded antigen to single-chain antibodies directed against DEC-205. Here, we investigated this promising approach for its enhancement of hepatitis B virus (HBV)-specific cellular and humoral immune responses and its antiviral effects in HBV transgenic mice. A plasmid DNA vaccine encoding mouse DEC-205 single-chain fragment variable (mDEC-205-scFv) linked with the hepatitis B surface antigen (HBsAg) was constructed. Vaccination with this fusion DNA vaccine in HBV transgenic mice induced robust antiviral T cell and antibody immunity against HBsAg. The levels of serum-circulating HBsAg and the HBV DNA copy number were downregulated by the induction of a higher HBsAg-specific response. Thus, in this study, we demonstrated the therapeutic efficacy of the novel mDEC-205-scFv-fused DNA vaccine in a mouse model of immune-tolerant, chronic HBV infection.

Association between IL-18 polymorphisms, serum levels, and HBV-related hepatocellular carcinoma in a Chinese population: a retrospective case-control study

BACKGROUND

Interleukin (IL)-18 gene polymorphisms have been found to play multiple roles in various diseases. However, studies focused on its involvement in hepatocellular carcinoma (HCC) remains controversial, and no much study has taken IL-18 serum levels into consideration. This study investigates the association between IL-18 polymorphisms and risk of hepatitis B virus-related HCC and their impact on serum IL-18 serum levels.

METHODS

A total of 153 patients and 165 healthy controls were enrolled in this study. Polymorphisms at positions -607C/A and -137G/C in the IL-18 gene were determined using the polymerase chain reaction-restriction fragment length polymorphism method. Serum IL-18 levels were determined with an ELISA kit.

RESULTS

No relationship was found between the -607C/A polymorphism and an individual's susceptibility to HCC. For the -137G/C polymorphism, the GC genotype and C allele were found to be significantly associated with decreased HCC risk (OR 0.506, 95% CI 0.290-0.882, P = 0.016 and OR 0.520, 95% CI 0.332-0.814, P = 0.004, respectively). The A(-607)C(-137) haplotype was also associated with a significant decreased risk of HCC (OR 0.495, 95% CI 0.294-0.834, P = 0.007). Serum IL-18 levels were found to be significantly lower in HCC patients compared to the control group in both the overall population and subjects with the different SNPs. Further, no association was found between serum IL-18 levels and the different genotypes within the same SNP.

CONCLUSION

These findings suggest that the -137G/C SNP in IL-18 may be a protective factor against HCC. Nevertheless, none of the studied SNPs was associated with the expression of IL-18.

Immune Response in Hepatitis B Virus Infection

Hepatitis B virus (HBV) can replicate within hepatocytes without causing direct cell damage. The host immune response is, therefore, not only essential to control the spread of virus infection, but it is also responsible for the inflammatory events causing liver pathologies. In this review, we discuss how HBV deals with host immunity and how we can harness it to achieve virus control and suppress liver damage.

Rethinking the pathogenesis of hepatitis B virus (HBV) infection

Chronic hepatitis B virus (HBV) infection affects approximately 375 million people worldwide. Current antiviral treatment effectively controls, but rarely clears chronic HBV infection. In addition, a significant portion of chronic HBV infected patients are not suitable for currently available antiviral therapy, and still face higher risk for cirrhosis and hepatocellular carcinoma. The poorly understood pathogenesis of HBV infection is the main barrier for developing more effective treatment strategies. HBV has long been viewed as non-cytopathic and the central hypothesis for HBV pathogenesis lies in the belief that hepatitis B is a host specific immunity-mediated liver disease. However, this view has been challenged by the accumulating experimental and clinical data that support a model of cytopathic HBV replication. In this article we systematically review the pathogenic role of HBV replication in hepatitis B and suggest possible HBV replication related mechanisms for HBV-mediated liver injury. We propose that a full understanding of HBV pathogenesis should consider the following elements. I. Liver injury can be caused by high levels of HBV replication and accumulation of viral products in the infected hepatocytes. II. HBV infection can be either directly cytopathic, non-cytopathic, or a mix of both in an individual patient depending upon accumulation levels of viral products that are usually associated with HBV replication activity in individual infected hepatocytes.

Doubtful Role of IL28B Polymorphism in Occult Hepatitis B Infection

AIMS

To investigate the influence of IL28B polymorphism in occult hepatitis B infection (OBI) and whether IL28B genetic variants are associated with hepatitis B virus (HBV)-specific T-cell responses.

PATIENTS AND METHODS

The rs12979860 IL28B genotype was determined in 34 OBI blood donors, 22 spontaneous HBV resolvers, 36 inactive HBV carriers and 25 seronegative donors. T-cell responses to HBV recombinant proteins were assessed by interferon-γ enzyme-linked immunospot assay.

RESULTS

The frequency of the IL28B CC genotype among OBI patients was similar to that of inactive carriers [41 vs. 39%, respectively, p = 0.961; odds ratio (OR) = 1.10; 95% confidence interval (CI) = 0.42-2.86; p = 0.845]. The IL28B CC genotype was found more frequently in spontaneous resolvers, although the differences were not significant (45 vs. 39%, spontaneous resolvers and inactive carriers, respectively; p = 0.828; OR = 1.31; 95% CI = 0.45-3.83; p = 0.622). HBV-specific T-cell responses were detected in OBIs, and significantly stronger T-cell responses towards hepatitis B envelope antigen were observed in those with the IL28B CC genotype. In spontaneous resolvers and inactive carriers, IL28B CC did not correlate with the magnitude of T-cell responses.

CONCLUSIONS

In OBI donors, IL28B CC correlates with the intensity of HBV-specific T-cell responses. In this study, IL28B CC is not statistically associated with OBI or with HBV clearance, but a larger number of cases is needed before completely ruling out its role in HBV infection.

Tumor necrosis factor-alpha blockage therapy impairs hepatitis B viral clearance and enhances T-cell exhaustion in a mouse model

Hepatitis B virus (HBV) reactivation and recurrence are common in patients undergoing immunosuppression therapy. Tumor necrosis factor (TNF) blockage therapy is effective for the treatment of many autoimmune inflammatory diseases. However, the role of TNF-α blockage therapy in the innate and adaptive immune responses against HBV is still not clear. A detailed analysis of HBV infection under TNF-α blockage therapy is essential for the prophylaxis and therapy for HBV reactivation and recurrence. In this study, HBV clearance and T-cell responses were analyzed in a HBV-transfected mouse model under anti-TNF blockage therapy. Our results demonstrated that under TNF-α blockage therapy, HBV viral clearance was impaired with persistent elevated HBV viral load in a dose- and temporal-dependent manner. The impairment of HBV clearance under anti-TNF-α blockage therapy occurred at early time points after HBV infection. In addition, TNF-α blockade maintained a higher serum HBV viral load and increased the number of intrahepatic programmed cell death (PD)-1(high)CD127(low) exhausted T cells. Furthermore, TNF-α blockade abolished Toll-like receptor 9 (TLR9) ligand-induced facilitation of HBV viral clearance. Taken together, TNF-α blockade impairs HBV clearance and enhances viral load, and these effects depend on early administration after HBV infection. Our results here demonstrate that early TNF-α blockade reduces viral clearance and persistently maintains elevated HBV viral load in a mouse model, suggesting that HBV may reactivate during therapy with TNF-α-blocking agents.

Circumventing failed antiviral immunity in chronic hepatitis B virus infection: triggering virus-specific or innate-like T cell response?

Therapeutic vaccination for the treatment of chronic hepatitis B has thus far been unsatisfactory. In this review, we discuss potential new therapeutic vaccination strategies and other immunotherapeutic approaches that aim to achieve efficient restoration of HBV immunity in chronically infected patients.

Combination versus sequential monotherapy in chronic HBV infection: a mathematical approach

Sequential monotherapy is the most widely used therapeutic approach in the treatment of hepatitis B virus (HBV) chronic infection. Unfortunately, under therapy, in some patients the hepatitis virus mutates and gives rise to variants which are drug resistant. We wonder whether those patients would have benefited from the choice of combination therapy instead of sequential monotherapy. To study the action of these two therapeutic approaches and to explain the emergence of drug resistance, we propose a stochastic model for the infection within a patient who is treated with two drugs, either sequentially or contemporaneously, and who, under the first kind of therapy develops a strain of the virus which is resistant to both drugs. Our stochastic model has a deterministic approximation which is a slight modification of a classic three-strain model. We discuss why stochastic simulations are more suitable than the study of the deterministic approximation, when modelling the rise of mutations (this is mainly due to the amplitude of the stochastic fluctuations). We run stochastic simulations with suitable parameters and compare the time when, under the two therapeutic approaches, the resistant strain first reaches detectability in the serum viral load. Our results show that the best choice is to start an early combination therapy, which allows one to stay drug resistance free for a longer time and in many cases leads to viral eradication.

Acute HIV infection is beneficial for controlling chronic hepatitis B

BACKGROUND

Coinfection with human immunodeficiency virus (HIV) and hepatitis B virus (HBV) is common. Most studies have concentrated on the effects of chronic HIV infection on HBV infection; however, studies on the effects of acute HIV infection on HBV infection are especially important to elucidate the potential mechanisms leading to complications from HIV/HBV coinfection.

METHODS

We evaluated the HBV DNA, hepatitis B surface antigen (HBsAg), and hepatitis B "e" antigen (HBeAg) in stored serum samples from 25 men with chronic hepatitis B who had acquired acute HIV infection.

RESULTS

All of the 25 men had decreased HBV DNA levels during acute HIV infection. Three men converted from HBsAg positive before HIV infection to HBsAg negative during acute HIV infection, and 10 men converted from HBeAg positive before HIV infection to HBeAg negative during acute HIV infection.

CONCLUSIONS

These data suggest that the early effects of HIV infection improve the immune response against HBV.

Association of TNF-α Promoter Polymorphism with HBV Associated Disease Outcome Among HBV Infected Patients from Orissa, Southern Part of East India

BACKGROUND

TNF-α promoter polymorphism has been known to be a potential predictive factor in patients with HBV infection. We therefore tried to investigate whether the TNF-α promoter polymorphism at position -238, -857 and -863 was associated with the outcome of HBV infection in a population from Orissa, southern part of East India.

METHODS

A total of 195 patients recruited for the study were classified into 85 controls and 110 HBV infected cases, which included 34 IC, 30 CLD, 32 LC and 14 HCC patients. The polymorphisms at the respective sites were detected by a PCR-RFLP followed by statistical analysis.

RESULTS

The frequency of the genotype -238 GG and the allele -238G in the cases (89.0% and 92.7% respectively) was significantly higher than that in the controls (68.2% and 82.2% respectively) (P < 0.001, OR = 3.8 and P = 0.001, OR = 2.73). Whereas the -238 GA genotype was significantly high in the control group (28.2%) when compared to the cases (7.2%) (P < 0.001, OR = 0.2). Similarly, the frequency of -863CC and the allele -863C was significantly higher among the cases (24.5% and 49.5%) compared to controls (1.17% and 34.7%), (P < 0.001, OR = 27.32 and P = 0.003, OR = 1.85), whereas the -863CA genotype was significantly high in the controls (67.0%) when compared to the cases (50.0%) (P = 0.01, OR = 0.49). Haplotype -863C/-857C/-238G in cases was significantly higher than controls (P = 0.002). Multivariate logistic regression analysis indicates that the genotype -863CC bears a negative association with liver disease progression.

CONCLUSION

The present study established an association of polymorphisms at site -238 and -863 of the TNF-α promoter with the outcome HBV infection and disease progression.

Human genes involved in hepatitis B virus infection

Persistent hepatitis B virus (HBV) infection is a significant public health problem because it is a major cause of chronic liver disease, cirrhosis, and hepatocellular carcinoma (HCC). Roughly one-third of the world population has been infected with HBV and there are about 350 million (5%-6%) persistent carriers. HBV causes 80% of all liver cancer cases and is the second most important carcinogen, after smoking tobacco. There is an approximate 90% risk of becoming a persistent carrier following perinatal infection in infants born to e antigen positive carrier mothers and a 30% risk in pre-school children. Only 5%-10% of adults become persistent carriers following infection. Of individuals persistently infected with HBV, 10%-30% will develop liver cirrhosis and HCC. These highly variable outcomes in both clearance rates and disease outcomes in persistently infected individuals cannot be fully explained by differences in immunological, viral or environmental factors. Thus, differences in host genetic factors may affect the natural history of hepatitis B.

Role of platelets in chronic liver disease and acute liver injury

Platelets contain not only hemostatic factors but also many growth factors that play important roles in wound healing and tissue repair. Platelets have already been used for the promotion of tissue regeneration in the clinical setting, such as dental implantation and plastic surgery. Thrombocytopenia, which is frequently found in patients with chronic liver disease and cirrhosis, is due to various causes such as decreased thrombopoietin production and accelerated platelet destruction caused by hypersplenism. However, the relationship between thrombocytopenia and hepatic pathogenesis and the role of platelets in chronic liver disease are poorly understood. In acute liver injury, it is reported that platelets are recruited to the liver and contribute to liver damage by promoting the induction of chemotactic factors and the accumulation of leukocytes in the liver, whereas platelets or mediators released by platelets can have a protective effect against liver injury. In this review, we highlight the recent accumulated knowledge concerning the role of platelets in chronic liver disease and acute liver injury.

Hepatitis C virus and vaccine development

The prevalence of Hepatitis C virus (HCV) is approximately 3% around the world. This virus causes chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. The effectiveness of interferon-α and ribavirin therapy is about 50% and is associated with significant toxicity and cost. Hence, generating new vaccines or drugs is an obligation. However, there is no vaccine available for clinical use. DNA vaccines have some advantages such as producing feasibility and generating intensive cellular and humoral immune responses. Activation and improvement of natural immune defense mechanisms is a necessity for the development of an effective HCV vaccine. This article discusses the current status of therapies for hepatitis C, the promising new therapies and the experimental strategies to develop an HCV vaccine.

An insight into the diagnosis and pathogenesis of hepatitis C virus infection

This review focuses on research findings in the area of diagnosis and pathogenesis of hepatitis C virus (HCV) infection over the last few decades. The information based on published literature provides an update on these two aspects of HCV. HCV infection, previously called blood transmitted non-A, non-B infection, is prevalent globally and poses a serious public health problem worldwide. The diagnosis of HCV infection has evolved from serodetection of non-specific and low avidity anti-HCV antibodies to detection of viral nucleic acid in serum using the polymerase chain reaction (PCR) technique. Current PCR assays detect viral nucleic acid with high accuracy and the exact copy number of viral particles. Moreover, multiplex assays using real-time PCR are available for identification of HCV-genotypes and their isotypes. In contrast to previous methods, the newly developed assays are not only fast and economic, but also resolve the problem of the window period as well as differentiate present from past infection. HCV is a non-cytopathic virus, thus, its pathogenesis is regulated by host immunity and metabolic changes including oxidative stress, insulin resistance and hepatic steatosis. Both innate and adaptive immunity play an important role in HCV pathogenesis. Cytotoxic lymphocytes demonstrate crucial activity during viral eradication or viral persistence and are influenced by viral proteins, HCV-quasispecies and several metabolic factors regulating liver metabolism. HCV pathogenesis is a very complex phenomenon and requires further study to determine the other factors involved.

Experimental HBsAg/anti-HBs complex assay for prediction of HBeAg loss in chronic hepatitis B patients treated with pegylated interferon and adefovir

BACKGROUND

We studied whether hepatitis B surface antigen (HBsAg)/anti-HBs immune complex levels in chronic hepatitis B (CHB) patients receiving antiviral therapy could be used as a response marker at baseline (BL) or early during treatment to predict treatment outcome.

METHODS

An experimental array-based assay (immunological multi-parameter chip technology [IMPACT]; Roche Diagnostics, Penzberg, Germany) served to determine HBsAg, anti-HBs and complex levels. We tested a panel of serum samples of 40 hepatitis B e antigen (HBeAg)-positive and 44 HBeAg-negative patients who received pegylated interferon and adefovir for 48 weeks.

RESULTS

HBsAg loss occurred in 4 of 40 HBeAg-positive and 4 of 44 HBeAg-negative patients. A total of 14 of 40 HBeAg-positive patients lost HBeAg and 12 of them formed anti-HBe. At BL, complexes were present in 83 (99%) patients, whereas free anti-HBs levels were detectable in 5 patients. Complex levels at BL and week 12 were higher in HBeAg-positive patients with HBeAg loss, compared to patients who retained HBeAg (P=0.002 and P=0.005, respectively). Receiver operating characteristic analysis for HBeAg loss in HBeAg-positive patients at BL and week 12 showed area-under-the-curve values of 0.79 (P=0.002) and 0.82 (P=0.003) for complex levels. We found no correlation in either HBeAg-positive or -negative patients between complex levels and HBsAg loss.

CONCLUSIONS

We demonstrated for the first time that before and during treatment HBsAg/anti-HBs immune complex levels can predict HBeAg loss in HBeAg-positive CHB patients treated with pegylated interferon and adefovir. Complexes were present in almost all patients at BL and were higher in patients who lost HBeAg. In conclusion, determining HBsAg/anti-HBs immune complex levels before and early during treatment could aid in selecting CHB patients with an optimal chance to achieve HBeAg loss.

New Epitope Peptides Derived from Hepatitis C Virus (HCV) 2a Which Have the Capacity to Induce Cytotoxic T Lymphocytes in HLA-A2+HCV-Infected Patients

Because cytotoxic T lymphocytes (CTLs) play an important role in the specific immunotherapy of hepatitis C virus (HCV) infection, a series of CTL epitopes has been defined from HCV genotype 1a or 1b protein. Here, we attempted to identify HCV2a-derived epitopes that are capable of inducing HLA-A2-restricted and peptide-specific CTLs. Peripheral blood mononuclear cells (PBMCs) of HLA-A2+ HCV2ainfected patients or healthy donors were stimulated in vitro with each of the HCV2a-derived peptides, which were prepared based on the HLA-A2-binding motif, and their peptide-specific and HLA-A2-restricted cytotoxicities were examined. The HCV2a 432-441, HCV2a 716-724, and HCV2a 2251-2260 peptides were found to efficiently induce peptide-specific CTLs from the PBMCs of HLA-A2+ HCV2ainfected patients. Cytotoxicity was mainly mediated by CD8+ T cells in a HLA class I-restricted manner. These results indicate that the HCV2a 432-441, HCV2a 716-724, and HCV2a 2251-2260 peptides might be applicable for peptide-based immunotherapy of HLA-A2+ HCV2a-infected patients.