In recent years, great achievements have been made in the therapy of viral hepatitis B and viral hepatitis C, as majority of hepatitis C patients can be clinically cured.Though current antiviral therapy is still unable to eradicate hepatitis B virus in infected hepatocyte and few patients could achieve HBsAg loss or seroconversion, end-stage liver disease like cirrhosis, liver failure and hepatocellular carcinoma have been dramatically prevented.The advances in treatments have prompted the progress in laboratory diagnosis of viral hepatitis.Here we review the progress in the field.

Objective:To get specific monoclonal antibodies ( mAbs) against PD-L1 which can block PD-1/PD-L1 binding, and explore the feasibility of its application on the treatment of chronic HBV infection preliminarily by in vitro and in vivo model. Methods:E. coli expression and series chromatography purification system were employed to get human and mouse PD-1/PD-L1 that had binding activity in vitro. By immunizing BALB/c mouse with purified recombination proteins of PD-L1,mAb hybridoma cell lines against PD-L1 were obtained. The reactivity with human/mice PD-L1 of individual antibody and the interaction blocking activity of the mAbs to PD-1/PD-L1 in vitro were examined by indirect chemiluminescence immune assay. Results: 8 cell lines against PD-L1 were obtained and 2 Anti-PDL1 mAbs (Ab5 &Ab6) performed strong immune activity to human/mice PD-L1 and blocking activity to PD-1/PD-L1. In the PBMC stimulation experiment of chronic HBV patient,Ab5 and Ab6 could promote theγ-IFN levels. With HBV in-fecting mice model,intravenous injections of these mAbs induced dramatically decrease of HBV DNA copies about 20 times, HBsAg levels in serum reduced to 30% of the baseline level. Conclusion:We obtained 2 PD-L1 mAbs with the reactivity to human/mice PD-L1 and blocking activity to PD-1/PD-L1. The 2 mAbs can promote T cell function in PBMC stimulation culture of chronic HBV patient, have significant antiviral effect in HBV transgenic mice and can be candidates for immunotherapy applications.

Hepatitis E, caused by hepatitis E virus (HEV) infection, usually leads to an acute clinical course, and is the most common diagnosis among cases of acute viral hepatitis. From 2008, there have been increasing reports of chronic HEV infection in immunocompromised patients such as organ transplant recipients. Without intervention with antiviral treatment, approximately 60% of HEV infections in organ transplant recipients evolve into chronic HEV infections. Of these chronic hepatitis E patients, 10% may develop liver fibrosis and progress to liver cirrhosis. This article reviews chronic HEV infection and treatment in organ transplant recipients.
Animals ; Antiviral Agents ; therapeutic use ; Hepatitis E ; drug therapy ; virology ; Hepatitis E virus ; genetics ; isolation & purification ; physiology ; Hepatitis, Chronic ; drug therapy ; virology ; Humans ; Transplant Recipients ; Transplants ; virology

Persistant infection of high-risk human papillomavirus (HPV) is the primary cause leading to cervical cancer, which is ranked as second cancer threatening the health of women following breast cancer.Development of HPV vaccine is very important because there is no effective therapeutics for cervical cancer.Three currently licensed HPV vaccines based on major capsid protein L1 in the foreign market confered good safety and efficacy in clinical trials, but the current price is expensive due to high cost, which limits the wide application in developing countries.So far, the vaccines have not been launced in China market.Here, we review the progress and the current status of the HPV vaccine, which will attract the readers’ interest on the forthcoming emergence of HPV vaccine in China.

Objective To quantitatively analyze the characteristics of a panel of murine anti-human papillomavirus(HPV)11 L1-derived virus-like particle( VLP ) monoclonal antibodies ( mAbs ) and establish the mAb-based methods for antigen quality analysis.Methods A panel of 22 murine anti-HPV11 mAbs were characterized in details with their isotype, and binding affinity, conformational sensitivity were examined quantitatively in the direct binding ELISA and Western blot.The hemagglutination inhibition activity of mAbs were identified using the hemagglutination inhibition assay and the pseudovirus ( PsV ) neutralization efficiency were examined quantitatively using the PsV-based neutralization assay.The type-specific, highly conformational sensitive and neutralizing mAbs were selected to be used in the sandwich ELISA assay.Results Based on the quantitative and semi-quantitative results, six type-specific, highly conformational sensitive and neutralizing mAbs (2A2, 4A1-3, 16G7, 14A6, 9C1 and 19C7) were identified.These mAbs, along with 10D6 were screened as the capture mAb or as the detection mAb in the sandwich ELISA.Conclusion The binding affinity, conformational sensitivity and neutralization efficiency of anti-HPV11 mAbs were characterized in details.A mAb-based sandwich ELISA assay (14A6:Ag:9C12-HRP) were developed, which could be used in the in vitro potency analysis of HPV11 VLP-based vaccine.

Objective To establish a mouse model of genital human papillomavirus (HPV) pseudovirion (PsV) transmission and evaluate the protective potency of HPV16 VLP vaccine.Methods HPV16 PsV with the encapsidated luciferase expressing plasmid Luc were generated from 293FT cells and purified by size-exclusion chromatography.The endpoint titers of HPV16 PsV-Luc were determined on 293FT cells, denoted as TRLU/mL.For in vivo genital challenge, mice were synchronized in a diestrus-like status by a subcutaneous injection with 0.1 μg β-estradiol and then with 3mg DepoProvera after 24 hours.Six hours prior to HPV16 PsV-Luc challenge, deeply anesthetized mice were intravaginally pretreated with 50 μL of 4%nonoxynol-9 ( N-9 ).HPV16 PsV-Luc was thoroughly mixed with 20 μL solution containing 4%carboxymethylcellulose ( CMC ) and intravaginally instilled using a positive-displacement pipette.Forty-eight hours after PsV-Luc challenge, mice were anesthetized and D luciferin was intravaginally instilled.After 3 minites, bioluminescence was measured with a cryogenically cooled Xenogen IVIS camera system.Then,the murine genital challenge model was used to determine the potency that HPV16 VLP vaccine is efficient at preventing HPV infection.Results HPV16 PsV-Luc was generated and purified from 293FT cells.HPV16 PsV-Luc was verified to containe L1 and L2 protein by Western blot.HPV 16 PsV-Luc successfully infected vaginal epithelial cells of mouse and the murine genital challenge model was established.To achieve consistent bioluminescence, the minimal dose of HPV16 PsV-Luc was 1.7 ×104 TRLU.The protective potency of HPV16 VLP vaccine was shown using this murine model.Our data showed that immune serum with over neutralizing antibody titer of 256-fold was sufficient to confer protection against HPV PsV genital infection .Conclusion The murine genital challenge model of HPV16 was successfully established, and the model is used to evaluate the potency of HPV16 VLP vaccine against in vivo genital HPV16 PsV challenge.Our model will benefit for the investigation of HPV neutralization and the potency evaluation of the HPV vaccine .

Although the efficacy of nucleos(t)ide analogue (NA) has been confirmed for treatment of chronic hepatitis B,long-term therapy has been recommended due to the high frequency of off-therapy viral DNA rebound and disease relapse.In this review,the RNA virion-like particles of hepatitis B virus (HBV) are integrated into the life cycle of HBV replication,and the potential significance of serum HBV RNA is systematically described.The production of HBV RNA virion-like particles should not be blocked by NA;in this regard,serum HBV RNA is found to be a suitable surrogate marker for the activity of intrahepatic covalently closed circular DNA (cccDNA),particularly among patients receiving NA therapy.Therefore,the concept of virological response is redefined as persistent loss of serum HBV DNA and HBV RNA.In contrast to hepatitis B surface antigen (HBsAg) that can originate from either the cccDNA or the integrated HBV DNA fragment,serum HBV RNA,with pregenomic RNA origination,can only be transcribed from cccDNA.Therefore,the loss of serum HBV RNA would likely be a promising predicator for safe drug discontinuation.The clinical status of consistent loss of serum HBV RNA accompanied with low serum HBsAg levels might be implicated as a "para-functional cure," a status nearly close to the functional cure of chronic hepatitis B,to distinguish the "functional cure" characterized as serum HBsAg loss with or without anti-HBs seroconversion.

Objective To express the recombinant caspid of genotype 4 hepatitis E virus(HEV) ORF2. Methods HEV recombinant capsid protein D66 was expressed in E. coli, using the ORF2 fragment (aa368-606, obtained from swine bile) of genotype 4 HEV. Results The recombinant capsid proteins D66 self-assemble to be particle with a radius of 13 nm through dimeric form in neutral solution. Coated particles reacted well with sera obtained from patients during acute or recovered phase of HEV infection. Immunofluorescence and immnoblot assay suggested that D66 bound and penetrated HepG2 cell lines, and the process of attachment was blocked by sera collected from patients during acute or recovered phase of HEV infection.Conclusion Recombinant D66 particles simulate the structure at the surface of genotype 4 HEV well and specifically adhere and penetrate the host cells, which lays the foundation for the investigation of the molecular mechanism of genotype 4 HEV infection.

Objective:To prepare and preliminarily identify the monoclonal antibodies(mAbs) specifically against 3D protein of Enterovirus 71(EV71),using bioinformatics to predict the epitopes of 3D,with HBc protein as a carrier.Methods: Artificial screening of 3D protein epitope sequences by bioinformatic method,inserted into the major immunodominant region(MIR) area of Hepatitis B virus core protein(HBc),to construct the recombinant protein.BALB/c mice were immunized with the recombinant virus like particles(VLPs),to prepare the mAbs against 3D protein of EV71.Affinity chromatography technology was used to purify the mAb.The indirect ELISA,ELISPOT,immunofluorescence and immunohistochemistry staining methods were used to identify the characteristic of the mAb.Results: We displayed 3D(aa34-43),3D(aa61-76) and 3D(aa151-164) epitopes by constructing fusion protein using HBc VLPs as a vector,after hybridization,one positive hybridoma cell line(3E1) was selected by ELISA.The isotype of 3E1 was IgG2a.The results of immunofluorescence and immunohistochemistry staining assay showed that the mAb 3E1 could specifically recognize EV71.Conclusion: The prepared mAb 3E1 can specifically recognizes the EV71,which laid the foundation for the detection of virus and further study on 3D protein,and verified the bioinformatics technology combined with HBc carrier displaying peptides could prepare mAb quickly and efficiently.

Objective To obtain monoclonal antibodies ( mAbs ) against neutrophil gelatinase-associated lipocalin ( NGAL ) and a chemiluminescense immune quantification assay based one paired mAbs.Methods Six-to-eight weeks old female BALB/c mice were immunized with the purified recombinant human NGAL antigen( rhNGAL) that was produced by the Escherichia coil expression system.The spleen was fused with hybridoma for screening anti-NGAL monoclonal antibodies by indirect ELISA.Western blot was implemented to identify the reactivity with native NGAL. Results The rhNGAL antigen was found to form disulfide cross-linked dimers and present excellent immunogenicity.The reaction titer of the immune serum of NGAL immunized mice was about 106.Thirty mAbs were screened by indirect ELISA, hereinto;the EC50 values of mAb23C12 and 38D10 were 0.034 g/mL, 0.022 g/mL respectively.The antibodies pair, 38D10/23C12-SAE labeled with AcridiniumEster(AE), were shown to work well in chemiluminescense immune response quantitative detection which was screened by NGAL standardand clinical urine samples.This detection can resolve positive and negative samples with a statistically significant difference (P<0.0001).And the correlation coefficient R2between NGAL quantitative results and that of the Abbott's NGAL chemiluminescence immune assay kit was greater than 0.97.The detection linear range was 10-1500 ng/mL, analytical sensitivity of the method was 0.63 ng/mL.Conclusion Highly purified rhNGAL antigen and specific anti-NGAL monoclonal antibodies are generated in this study.The detection capability of method is comparable with that of the international commercial kit.