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Liu J, Yu Y, Zhao H, Guo L, Yang W, Yan Y, Lv J. Latest insights into the epidemiology, characteristics, and therapeutic strategies of chronic hepatitis B patients in indeterminate phase. Eur J Med Res 2024; 29:343. [PMID: 38902822 PMCID: PMC11191257 DOI: 10.1186/s40001-024-01942-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 06/17/2024] [Indexed: 06/22/2024] Open
Abstract
As a hepatotropic virus, hepatitis B virus (HBV) can establish a persistent chronic infection in the liver, termed, chronic hepatitis B (CHB), which causes a series of liver-related complications, including fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). HCC with HBV infection has a significantly increased morbidity and mortality, whereas it could be preventable. The current goal of antiviral therapy for HBV infection is to decrease CHB-related morbidity and mortality, and achieve sustained suppression of virus replication, which is known as a functional or immunological cure. The natural history of chronic HBV infection includes four immune phases: the immune-tolerant phase, immune-active phase, inactive phase, and reactivation phase. However, many CHB patients do not fit into any of these defined phases and are regarded as indeterminate. A large proportion of indeterminate patients are only treated with dynamic monitoring rather than recommended antiviral therapy, mainly due to the lack of definite guidelines. However, many of these patients may gradually have significant liver histopathological changes during disease progression. Recent studies have focused on the prevalence, progression, and carcinogenicity of indeterminate CHB, and more attention has been given to the prevention, detection, and treatment for these patients. Herein, we discuss the latest understanding of the epidemiology, clinical characteristics, and therapeutic strategies of indeterminate CHB, to provide avenues for the management of these patients.
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Affiliation(s)
- Junye Liu
- Department of Clinical Laboratory, Honghui Hospital, Xi'an Jiaotong University, Youyi Dong Road, Xi'an, 710054, China
| | - Yan Yu
- Department of Clinical Laboratory, Honghui Hospital, Xi'an Jiaotong University, Youyi Dong Road, Xi'an, 710054, China
| | - Heping Zhao
- Department of Clinical Laboratory, Honghui Hospital, Xi'an Jiaotong University, Youyi Dong Road, Xi'an, 710054, China
| | - Lei Guo
- Department of Spinal Surgery, Honghui Hospital, Xi'an Jiaotong University, Youyi Dong Road, Xi'an, 710054, China
| | - Wenjuan Yang
- Department of Clinical Laboratory, Honghui Hospital, Xi'an Jiaotong University, Youyi Dong Road, Xi'an, 710054, China
| | - Yuzhu Yan
- Department of Clinical Laboratory, Honghui Hospital, Xi'an Jiaotong University, Youyi Dong Road, Xi'an, 710054, China
| | - Jing Lv
- Department of Clinical Laboratory, Honghui Hospital, Xi'an Jiaotong University, Youyi Dong Road, Xi'an, 710054, China.
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Li D, Xi W, Zhang Z, Ren L, Deng C, Chen J, Sun C, Zhang N, Xu J. Oral microbial community analysis of the patients in the progression of liver cancer. Microb Pathog 2020; 149:104479. [PMID: 32920149 DOI: 10.1016/j.micpath.2020.104479] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2019] [Revised: 04/17/2020] [Accepted: 08/28/2020] [Indexed: 02/07/2023]
Abstract
Liver disease has been reported to associate with oral microbiota. This study aimed to identify the salivary microbial structure in liver disease patients and determine whether the disease progression influence the bacterial composition. 16S rDNA high-throughput sequencing and bioinformatic analysis were used to examine oral bacterial diversity in the different status of hepatitis patients including 6 patients with Hepatitis B (Y), 6 patients with Hepatitis B Cirrhosis (YY) and 6 patients with liver cancer (C), and 6 healthy controls (T). Phylogenetic analysis revealed that the genera of Streptococcus, Prevotella, Actinomyces, Veillonella and Neisseria are predominant genus in the saliva of Y, YY, C patients and T group. Lautropia, Abiotrophia and Veillonella were enriched in Y patients, while Treponema, Selenomonas and Oribacterium were also existed in YY patients. Haemophilus, Porphyromonas and Filifactor had high abundance in C patients. The genera of Moryella, Leptotrichia, Lactobacillus, Dialister, Serratia, Enterococcus and Actinobacillus were decreased in all patient samples compared with healthy control samples which may be used for treatment of liver disease. Diversity analyses showed decreased diversity of salivary bacterial communities was discovered in the progress of the liver disease. These findings identified the oral microbiota dysbiosis in liver disease, which may providing available information and possible diagnostic biomarkers for liver patients.
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Affiliation(s)
- Daxu Li
- Department of Microbiology and immunology, School of Health Sciences Center, Xi'an Jiaotong University, Xi'an, China; Department of Stomatology, the First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, China
| | - Weijun Xi
- Stomatology Department, Xi'an Gaoxin Hospital, Xi'an, China
| | - Zhe Zhang
- Department of Stomatology, the First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, China
| | - Le Ren
- Department of Stomatology, the First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, China
| | - Chunni Deng
- Department of Stomatology, the First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, China
| | - Jianghao Chen
- Department of Stomatology, the First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, China
| | - Cong Sun
- Department of Stomatology, the First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, China
| | - Nan Zhang
- Department of Stomatology, the First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, China
| | - Jiru Xu
- Department of Microbiology and immunology, School of Health Sciences Center, Xi'an Jiaotong University, Xi'an, China.
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Lei Q, Li T, Kong L, Li L, Ding X, Wang X, Zhang X, Qin B. HBV-Pol is crucial for HBV-mediated inhibition of inflammasome activation and IL-1β production. Liver Int 2019; 39:2273-2284. [PMID: 31419377 DOI: 10.1111/liv.14214] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 08/07/2019] [Accepted: 08/09/2019] [Indexed: 12/12/2022]
Abstract
BACKGROUND & AIMS Hepatitis B virus (HBV) infection is the most critical factor underlying liver cirrhosis and hepatocellular carcinoma worldwide. IL-1β and IL-18, generated by activation of the inflammasome/caspase-1 signaling pathway, play important roles in the control and clearance of HBV. However, the specific relationship between the inflammasome response and IFN-α resistance or viral persistence is yet to be established. METHODS Blood samples of patients and supernatant fractions of HBV cell lines were collected for analysis and the effects on inflammasome activation and IL-1β production evaluated via enzyme-linked immunosorbent assay (ELISA), western blot, quantitative RT-PCR and immunofluorescence. RESULTS IL-1β and IL-18 levels produced in sera of IFN-α non-responders were significantly lower than those of responders and normal donors. Additionally, expression of IL-1β and inflammasome components was decreased in peripheral blood mononuclear cells (PBMC) of non-responders, compared with those of responders. In vitro experiments on HepG2, HepG2.2.15 and HepAD38 cell lines showed that HBV induces a significant decrease in IL-1β production through inhibiting activation of the NF-κB signaling and inflammasome/caspase-1 pathways. And hepatitis B virus polymerase (HBV-Pol) appeared crucial for these inhibitory effects of HBV. CONCLUSION IL-1β production is suppressed in HBV carriers and IFN-α non-responders. HBV induces a significant decrease in IL-1β production through inhibiting the NF-κB signaling and inflammasome pathways, for which HBV-Pol is a crucial requirement. Trial approval number: 20 173 402.
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Affiliation(s)
- Qingsong Lei
- Department of Infectious Diseases, Chongqing Key Laboratory of Infectious Diseases and Parasitic Diseases, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China.,Department of Oncology Radiotherapy Center, Chongqing University Cancer Hospital, Chongqing, China
| | - Tianju Li
- Department of Infectious Diseases, Chongqing Key Laboratory of Infectious Diseases and Parasitic Diseases, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China.,Department of Infectious Diseases, Chongqing Ninth Peoples Hospital, Chongqing, China
| | - Lingna Kong
- School of Nursing, Chongqing Medical University, Chongqing, China
| | - Lin Li
- Department of hepatic diseases, Chongqing Tranditional Chinese Medicine Hospital, Chongqing, China
| | - Xiaolin Ding
- Department of Infectious Diseases, Chongqing Key Laboratory of Infectious Diseases and Parasitic Diseases, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Xiaolin Wang
- Department of Infectious Diseases, Chongqing Key Laboratory of Infectious Diseases and Parasitic Diseases, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Xiaomei Zhang
- Department of Infectious Diseases, Chongqing Key Laboratory of Infectious Diseases and Parasitic Diseases, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Bo Qin
- Department of Infectious Diseases, Chongqing Key Laboratory of Infectious Diseases and Parasitic Diseases, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
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Mf Akbar S, Al-Mahtab M, I Khan S. Nature of Host Immunity during Hepatitis B Virus Infection and designing Immune Therapy. Euroasian J Hepatogastroenterol 2018; 8:42-46. [PMID: 29963460 PMCID: PMC6024052 DOI: 10.5005/jp-journals-10018-1256] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 02/14/2018] [Indexed: 12/23/2022] Open
Abstract
Hepatitis B virus (HBV) infections represent one of the major public health problems in global context. More than 2 billion people in the world have been infected with this virus at some point of time in their life and millions are chronically infected, indicating that chronic HBV-infected subjects remain as a living source of HBV transmission. The public health impact of this is tremendous. Considerable numbers of chronic HBV-infected individuals would eventually develop progressive liver diseases and their complications like hepatic failure, liver cirrhosis (LC), and hepatocellular carcinoma (HCC). Epidemiological studies have suggested that about 0.6 to 1.2 million people die annually from HBV-related liver diseases. These figures about death due to HBV and sufferings from HBV-related diseases indicate a notion of medical emergencies about HBV. In addition to these, the impact of HBV on health care delivery system moves beyond these numbers of HBV-related patients and HB-related deaths. This is because significant insights have already been developed about epidemiology, virology, and pathogenesis of HBV. Also, an effective and widely used preventive vaccine is available against HBV. In addition to these, antiviral drugs against HBV have been developed from early 1980s and several such drugs are now available commercially in the open market around the worldwide. Unfortunately, the ongoing therapeutic regimens could not stand the test of time and new insights about HBV pathogenesis are required for the development of new, novel, and evidence-based therapies for chronic HBV infections. How to cite this article: Akbar SMF, Al-Mahtab M, Khan SI. Nature of Host Immunity during Hepatitis B Virus Infection and designing Immune Therapy. Euroasian J Hepato-Gastroenterol 2018;8(1):42-46.
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Affiliation(s)
- Sheikh Mf Akbar
- Department of Medical Sciences, Toshiba General Hospital, Tokyo, Japan and Miyakawa Memorial Research Foundation, Tokyo Japan
| | - Mamun Al-Mahtab
- Department of Hepatology, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh
| | - Sakirul I Khan
- Department of Anatomy and Embryology, Graduate School of Medicine, Ehime University, Ehime, Japan
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Mandli J, Attar A, Ennaji MM, Amine A. Indirect competitive electrochemical immunosensor for hepatitis A virus antigen detection. J Electroanal Chem (Lausanne) 2017. [DOI: 10.1016/j.jelechem.2017.05.047] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Koutsianas C, Thomas K, Vassilopoulos D. Hepatitis B Reactivation in Rheumatic Diseases: Screening and Prevention. Rheum Dis Clin North Am 2016; 43:133-149. [PMID: 27890170 DOI: 10.1016/j.rdc.2016.09.012] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Hepatitis B virus (HBV) reactivation (HBVr) has been an increasingly recognized and appreciated risk of immunosuppressive therapies in rheumatic patients. Despite its potential for significant morbidity and mortality, HBVr is a fully preventable complication with appropriate pretreatment screening and close monitoring of susceptible patients. Better knowledge of the risk for HBVr with the different antirheumatic agents and the establishment of the new-generation oral antivirals in clinical practice has greatly improved the design of screening and therapeutic algorithms. In this review, all available data regarding HBVr in rheumatic patients are critically presented and a screening and therapeutic algorithm is proposed.
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Affiliation(s)
- Christos Koutsianas
- Joint Rheumatology Program, Clinical Immunology-Rheumatology Unit, 2nd Department of Medicine and Laboratory, National and Kapodistrian University of Athens School of Medicine, Hippokration General Hospital, 114 Vass, Sophias Avenue, Athens 115 27, Greece; Department of Rheumatology, The Dudley Group NHS Foundation Trust, Russells Hall Hospital, Pensnett Road, Dudley DY1 2HQ, West Midlands, UK
| | - Konstantinos Thomas
- Joint Rheumatology Program, Clinical Immunology-Rheumatology Unit, 2nd Department of Medicine and Laboratory, National and Kapodistrian University of Athens School of Medicine, Hippokration General Hospital, 114 Vass, Sophias Avenue, Athens 115 27, Greece
| | - Dimitrios Vassilopoulos
- Joint Rheumatology Program, Clinical Immunology-Rheumatology Unit, 2nd Department of Medicine and Laboratory, National and Kapodistrian University of Athens School of Medicine, Hippokration General Hospital, 114 Vass, Sophias Avenue, Athens 115 27, Greece.
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Akbar SMF, Al-Mahtab M, Khan MSI, Raihan R, Shrestha A. Immune therapy for hepatitis B. ANNALS OF TRANSLATIONAL MEDICINE 2016; 4:335. [PMID: 27761439 DOI: 10.21037/atm.2016.08.48] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Although several antiviral drugs are now available for treatment of patients with chronic hepatitis B (CHB), sustained off-treatment clinical responses and containment of CHB-related complications are not achieved in majority of CHB patients by antiviral therapy. In addition, use of these drugs is endowed with substantial long term risk of viral resistance and drug toxicity. The infinite treatment regimens of antiviral drugs for CHB patients are also costly and usually unbearable by most patients of developing and resource-constrained countries. Taken together, there is a pressing need to develop new and innovative therapeutic approaches for CHB patients. Immune therapy seems to be an alternate therapeutic approach for CHB patients because impaired or distorted or diminished immune responses have been detected in most of these patients. Also, investigators have shown that restoration or induction of proper types of immune responses may have therapeutic implications in CHB. Various immunomodulatory agents have been used to treat patients with CHB around the world and the outcomes of these clinical trials show that the properties of immune modulators and nature and designing of immune therapeutic regimens seem to be highly relevant in the context of treatment of CHB patients. In this review, the general properties and specific features of immune therapy for CHB have been discussed for developing the guidelines of effective regimens of immune therapy for CHB.
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Affiliation(s)
| | - Mamun Al-Mahtab
- Department of Hepatology, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh
| | - Md Sakilur Islam Khan
- Department of Anatomy and Embryology, Ehime University Graduate School of Medicine, Ehime, Japan
| | - Ruksana Raihan
- Department of Virology, AIMST University, Semeling, Bedong, Kedah, Malaysia
| | - Ananta Shrestha
- Department of Hepatology, The Liver Clinic, Liver Foundation, Kathmandu, Nepal
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Akbar SMF, Al-Mahtab M, Khan SI, Shrestha A, Tabassum S, Hiasa Y. Current trends in hepatitis B vaccination. Future Virol 2016. [DOI: 10.2217/fvl-2016-0025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
One of the major successes in the area of vaccinology is the emergence, development and usage of hepatitis B vaccine (a prophylactic vaccine against HBV). Hepatitis B vaccine has protected millions of individuals from acquiring HBV infection and has prevented liver cancer in the majority of vaccinated subjects. Although initially designed as prophylactic vaccines, accumulative evidence has shown that these vaccines may also be used to treat patients with chronic hepatitis B. At present, there are two main areas of discussion in hepatitis B vaccination; development of more effective prophylactic hepatitis B vaccine that can provide protection to all vaccine recipients, and designing hepatitis B-based therapeutic vaccines for treatment of chronic hepatitis B patients.
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Affiliation(s)
- Sheikh MF Akbar
- Department of Medical Sciences, Toshiba General Hospital, Tokyo, Japan
| | - Mamun Al-Mahtab
- Department of Hepatology, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh
| | - Sakirul I Khan
- Department of Anatomy & Embryology, Ehime University Graduate School of Medicine, Ehime, Japan
| | - Ananta Shrestha
- Department of Hepatology, The Liver Clinic, Liver Foundation, Nepal
| | - Shahina Tabassum
- Department of Virology, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh
| | - Yoichi Hiasa
- Department of Gastroenterology & Metabology, Ehime University Graduate School of Medicine, Ehime, Japan
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Koutsianas C, Thomas K, Vassilopoulos D. Prevention of HBV reactivation in patients treated with biologic agents. Expert Rev Clin Pharmacol 2016; 9:579-589. [PMID: 26775683 DOI: 10.1586/17512433.2016.1143773] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Owing to the sensitive equilibrium between the hepatitis B virus (HBV) and the host's immune system in infected and exposed individuals, the immunosuppression caused by biologic treatment has been strongly linked to HBV reactivation (HBVr). HBVr in the setting of biologic therapy is a cause of considerable morbidity, hospitalization, interruption of treatment and mortality. However, recent literature has established that this is a largely preventable problem. Thus, it is essential for clinicians using biologic agents to be aware of HBVr potential and screen all susceptible patients. The risk for HBVr may vary depending on the host's HBV infection status and the potency of immunosuppression. The appropriate pre-emptive antiviral prophylaxis or monitoring for individuals at risk is emphasized in the latest evidence-based guidelines, but a number of unanswered questions remain.
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Affiliation(s)
- Christos Koutsianas
- a Clinical Immunology-Rheumatology Unit, 2nd Department of Medicine and Laboratory , National and Kapodistrian University of Athens Medical School, Hippokration General Hospital , Athens , Greece.,b Department of Rheumatology , The Dudley Group NHS Trust, Russells Hall Hospital , Dudley , West Midlands , UK
| | - Konstantinos Thomas
- a Clinical Immunology-Rheumatology Unit, 2nd Department of Medicine and Laboratory , National and Kapodistrian University of Athens Medical School, Hippokration General Hospital , Athens , Greece
| | - Dimitrios Vassilopoulos
- a Clinical Immunology-Rheumatology Unit, 2nd Department of Medicine and Laboratory , National and Kapodistrian University of Athens Medical School, Hippokration General Hospital , Athens , Greece
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Decreased Diversity of the Oral Microbiota of Patients with Hepatitis B Virus-Induced Chronic Liver Disease: A Pilot Project. Sci Rep 2015; 5:17098. [PMID: 26606973 PMCID: PMC4660595 DOI: 10.1038/srep17098] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 10/26/2015] [Indexed: 02/08/2023] Open
Abstract
Increasing evidence suggests that altered gut microbiota is implicated in the pathogenesis of hepatitis B virus-induced chronic liver disease (HBV-CLD). However, the structure and composition of the oral microbiota of patients with HBV-CLD remains unclear. High-throughput pyrosequencing showed that decreased oral bacterial diversity was found in patients with HBV-CLD. The Firmicutes/Bacteroidetes ratio was increased significantly, which indicated that dysbiosis of the oral microbiota participated in the process of HBV-CLD development. However, the changing patterns of the oral microbiota in patients with HBV-induced liver cirrhosis (LC) were almost similar to patients with chronic hepatitis B (CHB). HBV infection resulted in an increase in potential H2S- and CH3SH-producing phylotypes such as Fusobacterium, Filifactor, Eubacterium, Parvimonas and Treponema, which might contribute to the increased oral malodor. These key oral-derived phylotypes might invade into the gut as opportunistic pathogens and contribute to altering the composition of the gut microbiota. This study provided important clues that dysbiosis of the oral microbiota might be involved in the development of HBV-CLD. Greater understanding of the relationships between the dysbiosis of oral microbiota and the development of HBV-CLD might facilitate the development of non-invasive differential diagnostic procedures and targeted treatments of HBV-CLD patients harbouring specific oral phylotypes.
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Clark DN, Hu J. Hepatitis B virus reverse transcriptase - Target of current antiviral therapy and future drug development. Antiviral Res 2015; 123:132-7. [PMID: 26408354 DOI: 10.1016/j.antiviral.2015.09.011] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 09/09/2015] [Accepted: 09/21/2015] [Indexed: 02/07/2023]
Abstract
Hepatitis B virus (HBV) infections rely on the proper functioning of the viral polymerase enzyme, a specialized reverse transcriptase (RT) with multiple activities. All currently approved antiviral drugs for the treatment of chronic HBV infection, except for interferon, target the RT and belong to the same chemical class - they are all nucleoside analogs. Viral DNA synthesis is carried out by the RT enzyme in several different steps, each with distinct RT conformational requirements. In principle, each stage may be targeted by distinct antiviral drugs. In particular, the HBV RT has the unique ability to initiate viral DNA synthesis using itself as a protein primer in a novel protein priming reaction. In order to help identify RT inhibitors and study their mechanisms of action, a number of experimental systems have been developed, each varying in its ability to dissect the protein priming stage and subsequent stages of viral DNA synthesis at the molecular level. Two of the most effective drugs to date, entecavir and tenofovir, can inhibit both the protein priming and the subsequent DNA elongation stages of HBV DNA synthesis. Interestingly, clevudine, a thymidine analog, can inhibit both protein priming and DNA elongation in a non-competitive manner and without being incorporated into the viral DNA. Thus, a nucleoside RT inhibitor (NRTI) can functionally mimic a non-NRTI (NNRTI) in its inhibition of the HBV RT. Therefore, novel NRTIs as well as NNRTIs may be developed to inhibit the DNA synthesis activity of the HBV RT. Furthermore, additional activities of the RT that are also essential to HBV replication, including specific recognition of the viral RNA and its packaging into viral nucleocapsids, may be exploited for antiviral development. To achieve a more potent inhibition of viral replication and ultimately cure chronic HBV infection, the next generation of anti-HBV therapies will likely need to include NRTIs, NNRTIs, and other agents that target the viral RT as well as other viral and host factors in various combinations. This article forms part of a symposium in Antiviral Research on "An unfinished story: from the discovery of the Australia antigen to the development of new curative therapies for hepatitis B."
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Affiliation(s)
- Daniel N Clark
- Department of Microbiology and Immunology, The Pennsylvania State University College of Medicine, Hershey, PA 17033, United States.
| | - Jianming Hu
- Department of Microbiology and Immunology, The Pennsylvania State University College of Medicine, Hershey, PA 17033, United States
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Tenofovir monotherapy after achieving complete viral suppression on entecavir plus tenofovir combination therapy. Eur J Gastroenterol Hepatol 2015; 27:871-6. [PMID: 25919771 DOI: 10.1097/meg.0000000000000368] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
OBJECTIVES It is unclear whether patients with chronic hepatitis B with partial response to entecavir (ETV) who have achieved complete viral suppression (CVS) with ETV plus tenofovir (TDF) combination therapy maintain CVS if switched to TDF or ETV. Our goal was to examine virologic outcomes in such patients. METHODS This is a retrospective cohort study of 57 ETV partial responders with chronic hepatitis B who showed CVS on ETV+TDF combination therapy, who were switched back to monotherapy with either ETV (n=16) or TDF (n=18), or continued on combination therapy (n=23). The majority of patients were Asian (91%) and male (65%), with a mean age of 41±12 years. RESULTS The patients switched back to ETV had significantly higher rates of virologic breakthrough by 6 months after the switch compared with their TDF counterparts (88 vs. 39%, P=0.004). Patients who remained on ETV+TDF also had virologic breakthrough, due to either confirmed or suspected nonadherence. On multivariate analysis inclusive of age, sex, and hepatitis B virus DNA levels at initiation of combination therapy, ETV (compared with TDF) was found to be an independent predictor for virologic breakthrough (odds ratio 112.7, P=0.03), as well as duration of CVS of less than 12 months while on ETV+TDF (odds ratio 60.2, P=0.03). CONCLUSION TDF monotherapy, especially in those who have had CVS for at least 12 months on combination therapy, may be considered for some ETV partial responders who have achieved CVS with combination therapy, given the financial advantage and convenience of monotherapy.
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13
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Slauenwhite D, Johnston B. Regulation of NKT Cell Localization in Homeostasis and Infection. Front Immunol 2015; 6:255. [PMID: 26074921 PMCID: PMC4445310 DOI: 10.3389/fimmu.2015.00255] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 05/07/2015] [Indexed: 01/23/2023] Open
Abstract
Natural killer T (NKT) cells are a specialized subset of T lymphocytes that regulate immune responses in the context of autoimmunity, cancer, and microbial infection. Lipid antigens derived from bacteria, parasites, and fungi can be presented by CD1d molecules and recognized by the canonical T cell receptors on NKT cells. Alternatively, NKT cells can be activated through recognition of self-lipids and/or pro-inflammatory cytokines generated during infection. Unlike conventional T cells, only a small subset of NKT cells traffic through the lymph nodes under homeostatic conditions, with the largest NKT cell populations localizing to the liver, lungs, spleen, and bone marrow. This is thought to be mediated by differences in chemokine receptor expression profiles. However, the impact of infection on the tissue localization and function of NKT remains largely unstudied. This review focuses on the mechanisms mediating the establishment of peripheral NKT cell populations during homeostasis and how tissue localization of NKT cells is affected during infection.
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Affiliation(s)
- Drew Slauenwhite
- Department of Microbiology and Immunology, Dalhousie University , Halifax, NS , Canada
| | - Brent Johnston
- Department of Microbiology and Immunology, Dalhousie University , Halifax, NS , Canada ; Department of Pediatrics, Dalhousie University , Halifax, NS , Canada ; Department of Pathology, Dalhousie University , Halifax, NS , Canada ; Beatrice Hunter Cancer Research Institute , Halifax, NS , Canada
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14
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Abstract
Infection with HBV is common worldwide, with over 350 million chronic carriers. Chronic HBV infection is associated with cirrhosis and hepatocellular carcinoma. All currently available oral antivirals are directed against the HBV polymerase enzyme, a reverse transcriptase. HBV polymerase contains several important domains and motifs which define its functions and reveal ways to further target it. This enzyme executes many functions required for the HBV replication cycle, including viral RNA binding, RNA packaging, protein priming, template switching, DNA synthesis and RNA degradation. In addition, HBV polymerase must interact with host proteins for its functions. Future therapeutics may inhibit not only the DNA synthesis steps which are carried out by the reverse transcriptase domain (as all current antivirals do) but other domains, functions and interactions which are essential to the HBV replication cycle.
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Affiliation(s)
- Daniel N Clark
- The Pennsylvania State University College of Medicine, Milton S Hershey Medical Center, PA 17033, USA
| | - Jianming Hu
- The Pennsylvania State University College of Medicine, Milton S Hershey Medical Center, PA 17033, USA
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Hadziyannis SJ. Update on Hepatitis B Virus Infection: Focus on Treatment. J Clin Transl Hepatol 2014; 2:285-91. [PMID: 26355326 PMCID: PMC4521240 DOI: 10.14218/jcth.2014.00026] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Revised: 09/21/2014] [Accepted: 09/21/2014] [Indexed: 12/11/2022] Open
Abstract
This review article is an update of the current treatment strategies available for chronic hepatitis B. In addition to achieving on-therapy clinical remission and suppression of HBV replication without resistance, the ultimate goal of therapy is the development of sustained remission and HBsAg loss after discontinuation of treatment. This is the closest possible to cure outcome for hepatitis B virus (HBV) infection. These goals can be achieved by response-guided courses of pegylated interferon (peg-IFN)-alpha at rates higher than 30%, both in hepatitis B e antigen (HBeAg)-positive and HBeAg-negative patients. Review of the data regarding discontinuation of long term NA treatment in HBeAg-negative patients revealed that stopping such therapy is safe with high rates of sustained off treatment responses that appear to be immunologically induced. Decreasing hepatitis B surface antigen (HBsAg) titers under therapy to <500, particularly <100 IU/mL, and adding a course of peg-IFN to ongoing long term nucleos(t)ide analogue (NA) therapy increase the percentage of sustained responses following discontinuation of NA treatment.
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Affiliation(s)
- Stephanos J. Hadziyannis
- Liver Unit and its Molecular Biology Laboratory, National and Kapodistrian University of Athens, Evgenidion Hospital of Athens, Athens, Greece
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Ramanan V, Scull MA, Sheahan TP, Rice CM, Bhatia SN. New Methods in Tissue Engineering: Improved Models for Viral Infection. Annu Rev Virol 2014; 1:475-499. [PMID: 25893203 PMCID: PMC4398347 DOI: 10.1146/annurev-virology-031413-085437] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
New insights in the study of virus and host biology in the context of viral infection are made possible by the development of model systems that faithfully recapitulate the in vivo viral life cycle. Standard tissue culture models lack critical emergent properties driven by cellular organization and in vivo-like function, whereas animal models suffer from limited susceptibility to relevant human viruses and make it difficult to perform detailed molecular manipulation and analysis. Tissue engineering techniques may enable virologists to create infection models that combine the facile manipulation and readouts of tissue culture with the virus-relevant complexity of animal models. Here, we review the state of the art in tissue engineering and describe how tissue engineering techniques may alleviate some common shortcomings of existing models of viral infection, with a particular emphasis on hepatotropic viruses. We then discuss possible future applications of tissue engineering to virology, including current challenges and potential solutions.
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Affiliation(s)
- Vyas Ramanan
- Harvard-MIT Division of Health Sciences and Technology, Institute for Medical Engineering and Science, Cambridge, Massachusetts 02139
| | - Margaret A Scull
- Center for the Study of Hepatitis C, Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065
| | - Timothy P Sheahan
- Center for the Study of Hepatitis C, Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065
| | - Charles M Rice
- Center for the Study of Hepatitis C, Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065
| | - Sangeeta N Bhatia
- Harvard-MIT Division of Health Sciences and Technology, Institute for Medical Engineering and Science, Cambridge, Massachusetts 02139
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
- Division of Medicine, Brigham and Women's Hospital, Boston, Massachusetts 02115
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Antihepatitis B virus activity of a protein-enriched fraction from housefly (Musca domestica) in a stable HBV-producing cell line. ScientificWorldJournal 2014; 2014:389560. [PMID: 25050391 PMCID: PMC4090482 DOI: 10.1155/2014/389560] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2014] [Revised: 05/27/2014] [Accepted: 05/28/2014] [Indexed: 01/12/2023] Open
Abstract
Hepatitis B virus (HBV) infection remains a major public health problem. Although several vaccines and therapeutic strategies are currently being implemented to combat HBV virus, effective antiviral therapy against HBV infection has not been fully developed. Alternative strategies and new drugs to combat this disease are urged. Insects and insect derivatives are a large and unexploited source of potentially useful compounds for modern medicine. In the present study, we investigated the first anti-HBV activity of a protein-enriched fraction (PE) from the larvae of the housefly (Musca domestica) in a stable HBV-producing cell line. HBsAg and HBeAg in the culture medium were measured by enzyme-linked immunosorbent assay. HBV-DNA was quantified by fluorescent quantification PCR. HBV core protein was assayed by immunofluorescent staining. Results indicate PE treatment inhibited both HBsAg, HBeAg secretion, and HBV-DNA replication. Furthermore, PE could also suppress HBV core protein expression. PE could be a potential candidate for the development of a novel and effective drug for the treatment of HBV infection.
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Tan L, Wu ZQ, Liu T, Gao ZL, Ke WM. Dynamic changes in serum HBsAg levels in HBeAg-positive chronic hepatitis B patients with different liver inflammation grades and fibrosis stages. Shijie Huaren Xiaohua Zazhi 2014; 22:2023-2027. [DOI: 10.11569/wcjd.v22.i14.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the dynamic changes in serum HBsAg levels in HBeAg-positive chronic hepatitis B patients with different liver histological inflammation grades and hepatic fibrosis stages.
METHODS: Serum HBsAg levels in HBeAg-positive chronic hepatitis B patients were detected by electrochemiluminescence. Serum HBsAg levels were compared between patients with grades 1, 2, 3 and 4 liver histological inflammation, and between those with stages 1, 2, 3 and 4 hepatic fibrosis.
RESULTS: Serum HBsAg levels in patients with grades 1, 2, 3 and 4 liver histological inflammation were 2998 COI/mL ± 2515 COI/mL, 4064 COI/mL ± 2468 COI/mL, 5513 COI/mL ± 2390 COI/mL and 5736 COI/mL ± 1838 COI/mL, respectively; while the values in patients with stages 1, 2, 3 and 4 hepatic fibrosis were 3159 COI/mL ± 2577 COI/mL, 4075 COI/mL ± 2149 COI/mL, 5670 COI/mL ± 2189 COI/mL and 5976 COI/mL ± 2128 COI/mL, respectively. There were significant differences in serum HBsAg levels between different liver inflammation grades, as well as between different hepatic fibrosis stages (F = 9.986, P < 0.000; F = 13.955, P < 0.000).
CONCLUSION: Serum HBsAg levels increase dynamically along with the damage of hepatic tissues in patients with HBeAg-positive chronic hepatitis B.
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Hadziyannis SJ, Vassilopoulos D, Sevastianos V, Hadziyannis E. Can Nucleos(t)ide Analogue (NA) Therapy Ever be Stopped in HBeAg-Negative Chronic Hepatitis B? ACTA ACUST UNITED AC 2014. [DOI: 10.1007/s11901-014-0236-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Nucleoside/nucleotide analog inhibitors of hepatitis B virus polymerase: mechanism of action and resistance. Curr Opin Virol 2014; 8:1-9. [PMID: 24814823 DOI: 10.1016/j.coviro.2014.04.005] [Citation(s) in RCA: 112] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Revised: 04/14/2014] [Accepted: 04/16/2014] [Indexed: 02/07/2023]
Abstract
Hepatitis B virus (HBV) polymerase and human immunodeficiency virus (HIV) reverse transcriptase are structurally related. However, the HBV enzyme has a protein priming activity absent in the HIV enzyme. Approved nucleoside/nucleotide inhibitors of the HBV polymerase include lamivudine, adefovir, telbivudine, entecavir and tenofovir. Although most of them target DNA elongation, guanosine and adenosine analogs (e.g. entecavir and tenofovir, respectively) also impair protein priming. Major mutational patterns conferring nucleoside/nucleotide analog resistance include the combinations rtL180M/rtM204(I/V) (for lamivudine, entecavir, telbivudine and clevudine) and rtA181V/rtN236T (for adefovir and tenofovir). However, development of drug resistance is very slow for entecavir and tenofovir. Novel nucleoside/nucleotide analogs in advanced clinical trials include phosphonates similar to adefovir or tenofovir, and new tenofovir derivatives with improved pharmacological properties.
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Hadziyannis E, Hadziyannis SJ. Hepatitis B surface antigen quantification in chronic hepatitis B and its clinical utility. Expert Rev Gastroenterol Hepatol 2014; 8:185-95. [PMID: 24417264 DOI: 10.1586/17474124.2014.876362] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Serum HBsAg levels have been quantified extensively in recent years with simple completely automated assays in the various phases of the natural course of chronic HBV infection, have been compared with cccDNA in the liver, with various markers of HBV replication and have been correlated with several viral, host and environmental variables. Low HBsAg levels in inactive carriers predict a spontaneous HbsAg loss. Quantification of HBsAg in serum at baseline and its decline under interferon-alfa based regimens, both in HBeAg-positive and HBeAg-negative CHB, provides important information on the prediction of sustained post-treatment outcomes and on subsequent HBsAg clearance. The value of HBsAg quantification in the monitoring of long term nucleos(t)ide analogue treatment of CHB and in the prediction of sustained response remains unclear. In this review, the most recent data regarding the overall clinical utility of HBsAg measurement in HBeAg-positive and -negative CHB and in their treatment, is critically presented.
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Affiliation(s)
- Emilia Hadziyannis
- Academic Department of Medicine, Hippokration Hospital, National and Kapodistrian University of Athens, 114 Vas. Sophias Ave, Athens 11529, Greece
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