1.Establishment of a One-Step Real-Time RT-PCR Method for the Detection of Venezuelan Equine Encephalitis Virus.
Shasha QIAN ; Biao HE ; Zhongzhong TU ; Huancheng GUO ; Changchun TU
Chinese Journal of Virology 2015;31(2):107-113
Venezuelan equine encephalitis (VEE) is a zoonotic disease caused by the Venezuelan equine encephalitis virus (VEEV) complex. This disease has not yet been reported in China, and it is therefore essential to establish a rapid and accurate method for detection of the virus in order to prevent and control this disease. In this study, a one-step real-time quantitative RT-PCR method was developed for the detection of the VEEV complex. A pair of specific primers and a Taqman probe were designed corresponding to a conserved region of the VEEV gene nspl, allowing the detection of all known strains of different sub- types of the virus. Using RNA synthesized by in vitro transcription as template, the sensitivity of this method was measured at 3.27 x 10(2) copies/microL. No signal was generated in response to RNA from Chikungunya virus (CHIKV), nor to RNA encoding the nsp1 fragment of Eastern equine encephalitis virus (EE-EV) or Western equine encephalitis virus (WEEV), all of which belong to the same genus as VEEV. This indicates that the method has excellent specificity. These results show that this one-step real-time quantitative RT-PCR method may provide an effective tool for the detection of VEEV in China.
China
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DNA Primers
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genetics
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Encephalitis Virus, Venezuelan Equine
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classification
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genetics
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isolation & purification
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Encephalomyelitis, Venezuelan Equine
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virology
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Humans
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RNA, Viral
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genetics
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Reverse Transcriptase Polymerase Chain Reaction
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methods
2.Prediction,synthesis and characteristics of B-cell epitopes of CSFV envelope glycoprotein E2
Siguo LIU ; Gang MA ; Xinglong YU ; Maolin ZHANG ; Changchun TU ;
Chinese Journal of Immunology 2001;0(07):-
Objective:Study on characteristics of two synthesizd peptides based on CSFV E2 protein. Methods:B cell epitopes of CSFV E2 antigen were predicted using accessibility and flexibility schemes, associated with antigenicity , secondary structure and multiple sites prediction. Two antigen peptides (Pep1 and Pep2) have been designed and synthesized and their reactivety were detected with 8 McAbs and antiserum against mE2 protein, then the peptides were conjugated with BSA and immunized rabbits respectively. Results:Both Pep1 and Pep2 could react with antiserum and McAb A11, Pep2 could interact with McAbD5 and McAbD8. Only Pep1 BSA conjugate can stimulate high level and specific antibodies.Conclusion: The peptide1 has good antigenicity.
3.Proteomic Analyses of Purified Particles of the Rabies Virus.
Zhongzhong TU ; Wenjie GONG ; Yan ZHANG ; Ye FENG ; Nan LI ; Changchun TU
Chinese Journal of Virology 2015;31(3):209-216
The rabies virus (RABV) is an enveloped RNA virus. It mainly damages the central nervous system and causes anencephaly in mammals and humans. There is now compelling evidence that enveloped virions released from infected cells can carry many host proteins, some of which may play an important part in viral replication. Several host proteins have been reported to be incorporated into RABV particles. However, a systematic study to reveal the proteomics of RABV particles has not been conducted. In the present study, after virus culture and purification by sucrose density gradient ultracentrifugation, a proteomics approach was used to analyze the protein composition of purified RABV particles to understand the molecular mechanisms of virus-cell interactions. Fifty host proteins, along with five virus-encoded structural proteins, were identified in purified RABV particles. These proteins could be classified into ten categories according to function: intracellular trafficking (14%), molecular chaperone (12%), cytoskeletal (24%), signal transduction (8%), transcription regulation (12%), calcium ion-binding (6%), enzyme binding (6%), metabolic process (2%), ubiquitin (2%) and other (14%). Of these, four proteins (beta-actin, p-tubulin, Cofilin, Hsc70) were validated by western blotting to be present in purified RABV particles. This novel study of the composition of host proteins in RABV particles may aid investigation of the mechanism of RABV replication.
Animals
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Humans
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Molecular Sequence Data
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Proteomics
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Rabies
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genetics
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metabolism
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virology
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Rabies virus
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chemistry
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genetics
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metabolism
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Viral Proteins
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analysis
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chemistry
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genetics
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metabolism
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Virion
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chemistry
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genetics
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metabolism
4.Re-discussion on bias.
Chinese Acupuncture & Moxibustion 2013;33(11):1043-1047
The reasons of bias that is caused in the design of randomized controlled trial are analyzed in this article. It is emphasized that the design of randomized controlled trial in TCM acupuncture should follow its basic concepts and cores and make clear normative standards of placebo acupuncture. The concept of real-time control is proposed and focusing on activating the nerve cells process in threshold field is advised, which will make profound influence on development of medical science of acupuncture and moxibustion.
Acupuncture Therapy
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standards
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Humans
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Placebo Effect
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Randomized Controlled Trials as Topic
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standards
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Research Design
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Treatment Outcome
5.Isolation and identification of the Akabane virus from mosquitoes in Yunnan Province, China.
Yun FENG ; Biao HE ; Shihong FU ; Weihong YANG ; Yuzhen ZHANG ; Changchun TU ; Guodong LIANG ; Hailin ZHANG
Chinese Journal of Virology 2015;31(1):51-57
To evaluate the prevalence of mosquito-borne viruses in Manshi and Ruili (Yunnan Province, China), we collected 2 149 mosquitoes (17 species) in August 2010. Virus isolation was undertaken by the cul- ture of baby hamster kidney cells (BHK-21 cells). Two virus-like isolates were obtained: DHL10M117 was isolated from collected in Mangshi; DHL10M110 was obtained from Anopheles vagus collected in Rui- li. Both isolates caused cytopathic effects,illness and death in suckling mice inoculated with these isolates via the intracerebral route. Two positive amplicons, 702-bp from the S segment and 456-bp from the M segment,were obtained using reverse transcription-polymerase chain reaction using primers specific for the Akabane virus (AKV). Phylogenetic analysis suggested that these two virus stains had a distant relation- ship with AKVs from Kenya and Australia,but were genetically close to those from Japan,South Korea, and Taiwan. However,they were separate from other Asian strains and grouped into a small branch. The highest nucleotide and amino-acid sequence identity of the S segment was found with the CY-77 strain from Taiwan (96.6% and 99.6% for DHL10M117 and 96.7% and 100% for DHL10M110,respectively). Com- parison of the M segment showed they shared the highest amino acid identity with CY-77 (99.6% and 100%, respectively), whereas the highest nucleotide identity was found with the Iriki strain from Japan (99.6% and 100%, respectively). Compared with the MP496 strain from Kenya,they displayed lower lev- els of sequence homology, at 69.7% and 70.0% for nucleotide sequences of the two loci,and 91. 0% for a- mino acids. Our results identified that DHL10M117 and DHL10M110 were strains of AKV,and provided molecular biological evidence for the existence of AKV in Yunnan Province. These AKV strains that are circulating in Yunnan Province share a close genetic relationship with strains from the rest of Asia. Culex tritaeniorhynchus and Anopheles vagus may serve as transmission vectors.
Amino Acid Sequence
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Animals
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Anopheles
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virology
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Base Sequence
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Bunyaviridae Infections
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virology
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China
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Cricetinae
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Female
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Humans
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Insect Vectors
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virology
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Male
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Mice
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Orthobunyavirus
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classification
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genetics
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isolation & purification
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physiology
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Phylogeny
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Sequence Homology
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Viral Proteins
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chemistry
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genetics
6.Influences on morphology and biomechanics in rabbit's femur cortex of ovariectomy
Haiming HUANG ; Xiaolin LI ; Shuqiang TU ; Lianghua JIANG ; Changchun LU ; Xiaofeng CHEN
Chinese Journal of Orthopaedics 2017;37(9):553-559
Objective To investigate the influences on the femur cortex of the rabbit after ovariectomy and its mechanism.Methods Eighty 6 months-old female pure New Zealand rabbits were divided into two groups:40 rabbits in ovariectomy group and 40 in sham-operation group.The weight averaged 2.2±0.28 kg.Four weeks and 8 weeks after operation,a series of tests were performed in both groups concerning the number,the volume,the rate and the maximal load of cortical bone porosity.The number,the length and the density of linear crack in rabbit femur cortex were documented after repetitive application of minor trauma.Results Micro-CT demonstrated that both on week 4 and 8 after operation,the number,the volume and the rate of cortical bone porosity were all significantly higher in ovariectomy group than that of the control group.Four weeks after operation,the biomechanical test showed the significantly lower average maximal load of rabbit femur in ovariectomy group (1 892.60±59.09) than that of in control group (1 949.25±53.12) (P=0.003).Eight weeks after operation,the average load of both groups decreased to some extent,which was 1 944.55±41.76 in control group and 1 692.40±85.08 in ovariectomy group respectively (P=0.000).However,the average maximal load of ovariectomy group decreased more significantly.Having application of repetitive minor trauma to the bone,the number,the length and the density of linear crack of cortical bone were 3.40± 1.67,216.80± 17.60 μm and 0.40±0.08/mm2 in ovariectomy group,and 2.00± 1.17,160.45± 16.89 μm and 0.29±0.13/mm2 in control group 4 weeks later.And after 8 weeks,they were 5.15±1.18,334.60±13.94 μm and 0.35±0.10/mm2 in ovariectomy group,and 3.10±1.37,182.10±9.80 μm and 0.24±0.09/mm2 in control group.The number,the length and the density of linear crack of cortical bone were all significantly higher in ovariectomy group than that of in control group both on week 4 and on week 8 after operation.Conclusion Ovariectomy increases the porosity of cortical bone of rabbit,destroys its biological property,accelerates the fatigued damage and delays the healing process.These changes may be attributed to fracture and delayed union after fracture.
7.Site-directed mutagensis of the major antigen E2 gene of CSFV, its high level expression in Escherichia coli and the immunonicity of recombinant E2 protein.
Xing-Long YU ; Chang-Chun TU ; Xing-Ran XU ; Mao-Lin ZHANG ; Yi-Xiang CHEN ; Bo-Hua LIU
Chinese Journal of Biotechnology 2003;19(4):439-443
Classical swine fever virus (CSFV), an enveloped positive-stranded RNA virus in the genus Pestivirus of the Flaviviridae family, is the causative agent of a highly contagious swine disease characterized by symptoms of hemorrhagic fever and immune depression, usually leading to substantial economic losses. The serological methods for detection of CSFV antibody such as ELISA are important means for the diagnosis of CSFV and immune surveillance. It is difficult to obtain CSFV antigen with high quality using traditional method because its titration titer is low in cell culture. CSFV has four structural protein named C, E0, El and E2. The E2 protein contains major antigenic determinants that are conserved between different CSFV strains and involved in neutralization by antibodies. So recombinant E2 protein can be developed as an alternative to the intact viral antigen. So far, CSFV E2 have not been expressed in E. coli with high level. Many factors, such as the secondary structure, the stability of 5' and 3' terminus of gene, the location of SD sequence and the bias of codes, are involved in the expressing level of foreign gene in E. coli . In this study, two sites of the E2 gene sequence were confirmed to be detrimental to its expression efficiency in E. coli through the computer-aided analysis. So they were mutated using recombinant PCR without changing the amino acids sequence of CSFV E2 gene. A plasmid was constructed by inserting the mutated E2 gene into the prokaryotic expression vector pET-28a(+) and named pETE2. The E. coli competent host BL21 (DE3)lysS transformed with pETE2 could express the E2 gene at high level, amounting to 28% of the total protein of the induced recombinant bacteria at the presence of IPTG. Except the hydrophobic transmembrane domain at C terminus, the recombinant E2 protein includes the total aa sequence. So it contains all the potential linear antigen epitopes of E2 protein because hydrophobic aa region can not form epitope. The recombinant E2 protein was CSFV-specific as proved by Western blotting and indirect ELISA. The rabbits immunized with the recombinant E2 can be protect from the challenge of hog cholera lapinized virus. This is the first report that E2 gene is expressed with high level expression in E. coli. In conclusion, it is an effective measure that mutate the CSFV E2 gene to increase its expression level in E. coli. The recombinant CSFV E2 protein possess fine immunonicity and can be used the antigen for the detection of CSFV antibody.
Antigens, Viral
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genetics
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immunology
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metabolism
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Blotting, Western
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Enzyme-Linked Immunosorbent Assay
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Escherichia coli
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genetics
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metabolism
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Mutagenesis, Site-Directed
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methods
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Polymerase Chain Reaction
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Recombinant Proteins
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genetics
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immunology
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metabolism
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Viral Envelope Proteins
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genetics
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immunology
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metabolism
8.Quantitative detection of anti-classical swine fever virus siRNA expression in cells by stem-loop RT-qPCR.
Shuai LIU ; Jiangnan LI ; Ting YUAN ; Fanli YANG ; Daxin PANG ; Changchun TU
Chinese Journal of Biotechnology 2012;28(1):26-36
RNA interference (RNAi) is a promising technology in development of specific antiviral therapy, but the quantitative detection of small interfering RNA (siRNA) expressed in vivo is the main challenge to assess its antiviral effect. In order to detect the siRNA molecules (siN1 and SiN2) particularly expressed in cells to inhibit the replication of classical swine fever virus (CSFV), serial specific stem-loop primers were designed and synthesized. Two of them (SLP-N1-6 and SLP-N2-8) were selected by screening in cross combination and successfully used in establishment of an optimal stem-loop RT-qPCR, which showed high specificity and sensitivity in detection of anti-CSFV siRNA expressed in PK-15 cells. The method was capable of detecting 10(2) to 10(8) copies of siRNA molecule with good parallel relationship (R(sq) = 0.999) and high amplification efficiency (Eff. = 98.2%). Therefore, the established stem-loop RT-qPCR can be used as an ideal tool in quantitative assessment of the anti-CSFV effects of RNAi in combination with detection of viral antigens using indirect immunofluorescent assay and TCID50, providing a novel technique for evaluating the antiviral effects of the siRNA expressed in anti-CSFV transgenic pigs to be established in future.
Animals
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Cell Line
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Classical swine fever virus
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genetics
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isolation & purification
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metabolism
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RNA Interference
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RNA, Small Interfering
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analysis
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genetics
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metabolism
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RNA, Viral
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genetics
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Real-Time Polymerase Chain Reaction
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methods
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Swine
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Transfection
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Viral Nonstructural Proteins
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genetics
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metabolism
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Virus Replication
9.Role of purine signaling in liver immune regulation
Journal of Clinical Hepatology 2023;39(6):1488-1496
Purines are mainly composed of ATP, NAD + , and nucleic acid. In addition to their key intracellular functions, NAD + , ATP, and their hydrolyzed products (including ADP, AMP, and adenosine) are important extracellular signals involved in physiological processes and pathological conditions. Purine signaling plays an important role in immune regulation of liver microenvironment. This article mainly summarizes the regulatory effect of purine signaling on immune cells in the liver and the effect of purine signaling on the progression of liver diseases by regulating the inflammatory and anti-inflammatory responses of immune cells in the liver.
10.Role of HBeAg-induced immune activition and immunosuppression in chronic hepatitis B
Journal of Clinical Hepatology 2024;40(5):1026-1031
Chronic hepatitis B induced by HBV infection is a significant risk factor leading to liver cirrhosis and liver cancer. Half a century ago, HBeAg was first discovered in the serum of HBV infected individuals, and although HBeAg does not participate in HBV infection or replication in hepatocytes, studies have shown that it can interfere with the innate and adaptive immune responses of the host and play an important role in immune activation and immunosuppression during chronic HBV infection. HBV has no cytotoxicity to the infected hepatocytes, and the antiviral action and inflammatory response mediated by immune response determine whether HBV is cleared or induces liver inflammation-related diseases. Therefore, this article reviews the formation of HBeAg and its immune activation and immunosuppression mechanisms in chronic HBV infection, with a focus on the different immune effects caused by HBeAg on innate immune and adaptive immune cells, and this article also elaborates on the dual role of HBeAg in inducing immune responses and explores the conversion role of HBeAg in different stages of chronic HBV infection.