A retrospective study on pathological and clinical characteristics of 3 932 children with liver diseases / 中华儿科杂志

<p><b>OBJECTIVE</b>To explore the pathological and clinical characteristics of children with liver diseases by retrospective study on clinical and liver biopsy pathological data of children with liver diseases.</p><p><b>METHOD</b>This retrospective analysis was performed at Beijing No. 302 Hospital among 3 932 children with liver diseases who visited the hospital from January 2001 to December 2012. The kinds of diseases were compared with the results of 1983-2000.</p><p><b>RESULT</b>(1) Liver biopsy was successful in 99.72% (3 932/3 943) of cases of 2001-2012 group, complications occurred in 31 children only. (2) Of the 3 932 cases, 2 647 (67.32%) had hepatitis , non-hepatotropic viral hepatitis and non viral liver disease were seen in 365 cases (9.28%), and 920 cases (23.4%), respectively. Among 2 647 cases with viral hepatitis, 2 115 were hepatitis B (79.90%), 521 hepatitis C (19.69%), 7 were hepatitis A (0.26%) and 4 hepatitis E (0.15%), respectively. (3) In 2001-2012 group, the degrees of inflammatory activity (>G2) of liver were seen in 9.57% (202/2 111) patients with hepatitis B, while 23.57% (132/560) in 1983-2000 group. There was significant difference between the two groups (χ(2)=80.36, P=0.00 ). (4) Significant difference was observed in the rate of non viral liver disease between 2001-2012 group (23.40%, 920/3 932) and 1983-2000 group (9.61%, 98/1 020) (χ(2)=93.46, P=0.00). In 2001-2012 group, including 46 kinds of diseases, which were significantly higher than those of 1983-2000 group (18 kinds). In 2000-2012, the main causes of diseases were liver degeneration (18.26%, 168/920), drug-induced liver injury (13.59%, 125/920), fatty liver (8.80%, 81/920) and liver glycogen accumulation disease (8.70%, 80/920). While in 1983-2000 group, the main causes were liver degeneration (20.41%, 20/98), fatty liver (16.33%, 16/98), glycogen storage disease (10.20%, 10/98) and myopathy (9.18%, 9/98).</p><p><b>CONCLUSION</b>Liver biopsy in children is safe and feasible. Hepatitis B virus was ranked first in children with liver diseases in 2001-2012 group. The kinds of non viral hepatic disorders had changed and extended.</p>

The packaging and purification of recombinant adeno-associated virus loaded with anti-amyloid ? peptide single-chain antibody gene / 基础医学与临床

Objective To produce and purify recombinant adeno-associated virus(AAV) loaded with anti-amyloid ? peptide single-chain antibody gene for gene therapy of Alzheimer's disease.Methods The plasmid pSNAV2.0-Abeta-scFv was used to transform BHK-21 cell by Lipofectamine 2000 for stable package cell line establishment.The helper virus HSV1-rc/?UL2 was used to transfect package cell for anti-amyloid ? peptide single-chain antibody gene loaded recombinant adeno-associated virus production.The chloroform-PEG/NaCl-chloroform extraction and ion-exchange chromatography were employed for recombinant AAV purification.SDS-PAGE and PCR amplification were adopted for purified virus identification.The final virus physical titer was determined by digoxin-labeled DNA probes.The effect of gene therapy was tested with transgenic mice by water maze test.Results The purity of recombinant adeno-associated virus with our target gene reach up to 98% after stable cell package and serial purification.The physical titer of the final virus was 1?1012vg/mL.The latency of treated mice in water maze test were reduced significantly.Conclusion The adeno-associated virus carrying anti-amyloid? peptide single-chain antibody gene was produced by HSV1system and purified.The animal behavior test demonstrated the recombinant AAV waseffective in the gene therapy of Alzheimer's disease.

Screening and application of human-derived HBsAg bacteriophage single chain antibody in clinical diagnosis / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To identify human single chain Fv antibody (ScFv) against hepatitis B viral surface antigen.</p><p><b>METHODS</b>The recombinant phages were panned by HBsAg which was coated in a microtiter plate, after five rounds of biopanning, 56 phage clones were identified specific to HBsAg. The specificity of ScFv was evaluated by ELISA and immunohistochemistry, respectively.</p><p><b>RESULTS</b>The data of HB sAg-ScFv DNA digestion and DNA sequencing showed that the ScFv gene is composed of 750 bp. ELISA and immunohistochemistry demonstrated that the human single chain Fv antibody against hepatitis B surface antigen has a specific combination character with hepatitis B surface antigen of different sources and paraffin-embedded patients tissue specimens, it did not react with normal liver tissue and HCV.</p><p><b>CONCLUSIONS</b>The application of HBsAg specific ScFv in immunohistochemistry was successfully achieved.</p>

Inducible expression of non-structural protein 3 of hepatitis C virus in E. coli / 中华实验和临床病毒学杂志

<p><b>BACKGROUND</b>To express recombinant non-structural protein 3 of hepatitis C virus (HCV) in E. coli.</p><p><b>METHODS</b>The non-structural 3 (NS3) region DNA fragment of HCV was amplified by polymerase chain reaction (PCR) and inserted into inducible proeukaryotic expressive vector pET 30C(+)at Bam H1/EcoR1 sites. The competent BL21 (DE3) E.coli was transformed, and then cultured and induced with IPTG. The expressed HCV NS3 protein was confirmed with ELISA and dot blot hybridization using HCV NS3-specific single chain Fv (ScFv) antibody.</p><p><b>RESULTS</b>1 893 bp DNA fragment of HCV NS3 coding region was amplified by PCR technique. HCV NS3 expressive vector pET-NS3 was constructed. After transformation with pET-NS3 and induction with IPTG, recombinant HCV NS3 protein was expressed and confirmed by specific ELISA and dot blot hybridization.</p><p><b>CONCLUSIONS</b>The recombinant HCV NS3 can be expressed in E. coli.</p>

Screening and cloning gene of hepatocyte protein interacting with hepatitis C virus core protein / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To clone the unknown gene of hepatocyte protein interacting with hepatitis C virus core protein.</p><p><b>METHODS</b>Using the yeast dual hybrid system 3, bait plasmids of hepatitis C virus core were constructed. After identifying hepatitis C virus core protein that could stably expressed in AH109 yeast strains, we performed yeast two hybrid by mating AH109 with Y187 that transformed with liver cDNA library plasmids pACT2 and then plated on quadrople dropout (QDO) medium and assayed for alpha-gal activity. The genes of yeast colonies that could grow on QDO and had alpha-gal activity were sequenced.</p><p><b>RESULTS</b>Among the 30 positive colonies, we blasted the gene of the sixth colony; we coined human hepatitis C virus binding protein 6(Hu Hcbp6) with Genbank, realized that the Hu Hcbp6 shares as much as 98% homology with two cDNA without knowing functions. We have proved that Hu Hcbp6 could interact with hepatitis C virus core protein.</p><p><b>CONCLUSIONS</b>Hepatitis C virus core binding protein (Hu Hcbp 6 Genbank number: AY032594) was successfully cloned and identified. The study partly paved the way for investigating physiological function of the Hu Hcbp6.</p>

Preparation of human single chain Fv antibody specifically against hepatitis C virus E2 antigen / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To identify human single chain Fv antibody (ScFv) against hepatitis C viral E2 antigen and its value clinically.</p><p><b>METHODS</b>The recombinant phages were panned by E2 antigen which was coated in a microtiter plate. After five rounds of biopanning, 56 phage clones were identified specific to E2 antigen. The affinity and specificity of ScFv were evaluated by ELISA and immunohistochemistry, respectively.</p><p><b>RESULTS</b>The data of E2-ScFv DNA digestion and DNA sequencing showed that the ScFv gene was composed of 750bp. ELISA and immunohistochemistry demonstrated that the human single chain Fv antibody against HCV E2 antigen had a specific combination character with hepatitis C virus E2 antigen.</p><p><b>CONCLUSIONS</b>ScFv, having a sutestantial affinity and specificity and being easy to prepare, is valuable in the detection of HCV E2 antigen.</p>

Construction and expression of humanized anti-HBsAg scFv targeting interferon-alpha in escherichia coli / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To develop a bacteria expression system to produce the fusion protein of humanized anti-HBsAg scFV and interferon-alpha.</p><p><b>METHODS</b>The expression vector was constructed after cleaving the plasmids harboring the humanized anti-HBsAg scFv and interferon alpha respectively and ligating to linearized pET22b subsequence. The expression of fusion protein in E.coli was analyzed by SDS-PAGE. The binding activity and antiviral activity of the fusion protein was characterized by competing inhibition test and cytopathic effect reduction.</p><p><b>RESULTS</b>The plasmid harboring the in frame arranged fusion gene was constructed and identified. After induction for 12h, a new band close to 4.5 10(4) was observed using SDS-PAGE. Results of competing ELISA and cytopathic effect reduction showed the fusion protein retained its specific binding activity and antiviral activities.</p><p><b>CONCLUSIONS</b>The construction and expression of the fusion gene of humanized anti-HBsAg scFv and interferon in E.coli are successful.</p>

Epitope mapping of hepatitis C virus non-structure 3 protein from a 7 peptide phage library by using immobilized specific monoclonal antibody / 中华传染病杂志

Objective To screen HCV NS3 mimotopes by using monoclonal antibody and phage peptide library. Methods Using HCV NS3 monoclonal antibody as selective molecule, a 7 mer phage peptide library was biopanned and positive clones were selected by ELISA, competition assay and DNA sequencing. Results 13 positive clones were chosen for DNA sequencing. From the experiment and sequen-cing comparsion results, one epitope was confirmed as the mimotope of HCV NS3. Conclusions HCV mimotope is obtained by phage peptide library screening.

Cloning and sequence analysis of 4 amastin genes from Leishmania parasites / 中华传染病杂志

Objective To clone amastin coding genes from different strains of Leishmania parasites. Methods Using amastin cDNA sequence as the reference, dbEST data base established by National Center Biotechnology Information (NCBI), USA, was searched by BLAST tool. A 309 bp DNA fragment of Leishmania major was found and used as the probe for the screening of a DNA library. The amastin gene of Leishmania major Abdou was cloned and sequenced. Specific primers were designed and amastin genes for Leishmania mexicana WR972, Leishmania brizeliensis and Leishmania amazonensis joseph were amplified by polymerase chain reaction. Results The amastin genes from 4 strains of Leishmania parasites were cloned and sequenced. It was found that all 4 amastin genes contained unique open reading frame of 552 bp and encoded amastin protein of 183 amino acid residues. Conclusion The amastin genes of 4 strains of Leishmania parasites were successfully cloned.

EFFECT OF HEPATITIS B VIRUS CORE PROMOTER GENE HETEROGENEITY ON ITS TRANSCRIPTIONAL ACTIVITY / 解放军医学杂志

Polymerase chain reaction was employed to amplify the whole HBV CP region from the serum of patients with chronic hepatitis B virus(HBV) infection, and then the PCR products were subcloned into pGEM Teasy vectors. Clones were randomly selected to be sequenced and the selected clones were compared to look for the difference.The sequencing results suggested that each sequence of selected clones was different and there were HBV quasispecies groups in patients. There were hot deletion region and point mutation near the TATA like box of CP gene. To address whether the mutations were responsible for the transcriptional activity, the wild type(wt) and the mutants of HBV CP genes were subcloned into pcDNA3 1( ) vectors, respectively. The reverse oriented clones were digested with KpnI and XhoI, and cloned into the KpnI and XhoI sites of the chloramphenicol acetyltransferase (CAT) expressing vector (pCAT3 basic).The recombinant CAT plasmids were transfected into HepG2 cells using lipofectamine PLUS reagent, and the CAT expression which indirectly represented the transcriptional activity of HBV CP lying upstream of CAT gene was detected with a CAT ELISA kit. The restriction enzyme digesting results indicated that the recombinant CAT plasmids were successfully constructed, and the transfection tests indicated that the transcriptional activity of the mutants with deletion or substitute point mutation of TATA like box were reduced in comparison with that of CPwt. The HBV CP gene heterogeneity downregulated the transcriptional activity to some extent.

Preparation and immunohistochemical study of human single chain Fv antibody against hepatitis C virus core antigen / 解放军医学杂志

Objective To detect hepatitis C virus core antigen in 7721 cells transfected with HCV cDNA by immunohistochemistry method with human single chain Fv antibody(scFv). Methods The recombinant phages were panned by core antigen which was coated in a microtiter plate. After three rounds of biopanning, 48 clones were identified specific to core antigen. The affinity and specificity of scFv were evaluated by ELISA and immunohistochemistry. Results ScFv-core DNA digestion and sequence data showed that the scFv gene was composed of 774bp. Conclusion Human single chain Fv antibody against HCV core antigen has a specific combining capacity with hepatitis C virus core antigen.

Expression of soluble human anti-idiotypic single chain Fv antibody to hepatitis C core protein in E. coli / 解放军医学杂志

Objective To express soluble human anti-idiotypic single chain Fv to hepatitis C core protein in E.coli. Methods Using phage display technique, the semisynthetic phage library was panned by HCV core monoclonal antibody which was coated in a microtiter plate. After three rounds of biopanning, 53 clones were identified specific to HCV core antibody. The specificity of anti-idiotypic scFv was determined by ELISA. After digested with Sfi/Not, the selected HCV core anti-idiotypic scFv positive clone was subcloned into the vector pCANTAB5E for the expression of E-tagged soluble anti-idiotypic scFv. The E.coli XL1-Blue was transformed and induced by IPTG. The specificity of anti-Id scFv was evaluated with ELISA. Results HCV core anti-Id scFv DNA digestion and sequence data showed that the scFv gene was composed of 774bp. ELISA results demonstrated that the soluble human HCV core anti-idiotypic scFv to HCV core monoclonal antibody had a specific combination character. The molecular weight of expressed HCV core anti-idiotypic scFv was 28kD as shown by SDS-PAGE. Conclusion HCV core anti-Id scFv has been successfully expressed in E.coli.

To screen binding protein of hepatitis B virus core promoter with phage display technic / 解放军医学杂志

Objective To screen the HBV core promoter binding protein, and to investigate their potential role in the replication of HBV DNA. Methods By using HBV core promoter being used as a selective molecule, the T7select human liver cDNA library was biopanned and the positive clones were selected. Results After phage display screening, the positive plaques was amplified and then cloned into the pGEM-Teasy vector. Six positive plaques were chosen for DNA sequencing. The binding protein of HBV core promoter was identified as caboxypeptidase N(CPN) by BLAST. Conclusion The results suggest that phage display screening of binding protein of HBV core protein provides a new approach to study the replication mechanism of HBV DNA.

Screening of binding protein of hepatitis C virus NS4A by phage display from human liver cDNA library / 解放军医学杂志

Objective To screen the HCV NS4A binding protein. Methods By using HCV NS4A as a solidified selective molecule, the T7 select human liver cDNA library was biopanned and the positive clones were selected. After screening, the positive plaques was amplified and then cloned into the pGEM-Teasy vector. Two positive plaques were chosen for DNA sequencing. Results The binding protein of HCV NS4A was identified as mitogen-activated protein kinase (MAPK)-activated protein kinase 5 (MAPKAPK5) by BLAST. Conclusion This approach provides a new way for the study of the pathogenic mechanism of HCV infection.

Screening of mimotopes of swine influenza virus A (H1N1) by phage display technology / 解放军医学杂志

Objective To screen the specific antigen mimotopes of influenza A(H1N1)virus by phage display technology,in order to pave a way to develop novel influenza vaccine.Methods Using human convalescent serum of pandemic influenza A(H1N1)in 2009 as solid-phase selective molecule,an artificial synthesized phage randomly displaying cyclic 7-mer peptide was screened with three rounds of "absorption-elution-amplification" selection.At the end of the third round selection,32 clones were randomly chosen from the top-agar phage plaques and placed onto E.coli ER2378 in logarithmic growth phase.After culturing for 5 hours,the positive clones were identified by enzyme linked immunosorbent assay(ELISA),cross reaction test and competitive inhibition assay.The identified positive clones were analyzed by DNA sequencing.The decoded amino acids sequences,which displayed on the surface of phage,were aligned with the hemagglutinin(HA)gene of influenza virus by homology comparison for definition of the mimotopes of influenza A(H1N1)virus.Results After enriching the specific antibody-binding phages from phage displaying peptide library,12 positive clones were chosen from 32 randomly selected clones.DNA sequencing and homology comparison showed that one epitope PLHARLP was confirmed as mimotope of swine influenza A(H1N1)virus antigen,which was composed of the 52nd,53rd,59th,60th,61st,83rd and 271st amino acid.Conclusions Swine influenza A(H1N1)mimotope has been obtained by cyclic 7-mer peptide phage library screening.This result provides a basis for developing new influenza virus vaccine from virus antigen mimotopes.

EPITOPE MAPPING OF HEPATITIS C VIRUS CORE PROTEIN FROM A PEPTIDE PHAGE LIBRARY BY USING IMMOBILIZED SPECIFIC MONOCLONAL ANTIBODY / 解放军医学杂志

To screen HCV core mimotopes,HCV core monoclonal antibody was used as immobilized molecule,and a 12 mer phage peptide library was biopanned and positive clones were selected by enzyme linked immunoadsorbent assay(ELISA), competitive inhibition assay, and DNA sequencing. 10 positive clones were chosen for DNA sequencing. From the experiment and sequencing comparison results,one epitope was confirmed as a mimotope of HCV core protein. The study might provide a new approach for HCV therapy and vaccine development.

SCREENING AND IDENTIFICATION OF ANTI-IDIOTYPIC ANTIBODY SINGLE CHAIN VARIABLE FRAGMENT AGAINST HCV NS4A / 解放军医学杂志

To screen anti idiotypic single chain variable fragments(anti Id scFv)against hepatitis C virus NS4A(HCV NS4A)so as to lay a foundation for developing anti Id scFv vaccine againist the hepatitis C virus. The recombinant phage antibody library was panned by hepatitis C virus NS4A monoclonal antibody which was coated in a microwell plate. After five rounds of biopanning, 82 clones specific to HCV NS4A antibody were determined with the enzyme linked immunoadsorbent assay(ELISA). The specificity of anti idiotypic scFv was identified by ELISA and competitive inhibition assay. The DNA sequence of the positive clone was determined. The result showed that HCV NS4A anti Id scFv had a specific combination character with hepatitis C virus NS4A monoclonal antibody. The DNA sequence data showed that the anti Id scFv coding gene included 789 bp. The results suggested that the anti Id scFv fragments to HCV NS4A monoclonal antibody could be successfully selected by recombinant phage antibody library screening technique, which might pave a way for the study of new preventive and therapeutic strategy of hepatitis C using anti Id scFv.

SCREENING AND CHARACTERIZATION OF HUMAN PHAGE ANTIBODY TO HEPATITIS C VIRUS E2 ANTIGEN / 解放军医学杂志

To screen and characterize human phage antibody to hepatitis C virus E2 antigen. The recombinant phages were panned by HCV E2 antigen which was coated in a microwell plate. After three rounds of biopanning, 56 clones specific to HCV E2 antigen were obtained. The specificity of scFv was determined by ELISA method and cross reaction with BSA and competitive inhibition assay. HCV E2 phage antibody had a specific combination character with recombinant hepatitis C virus E2 antigen. The DNA sequence data showed that the scFv coding gene was 771bp in size

Screening of promoter DNA-binding protein of iNOS gene by phage display technique from human liver cDNA library / 解放军医学杂志

Objective To screen promoter DNA-binding protein of inducible nitric oxide synthase gene by using phage display technique from human liver cDNA library, and to study the expression and regulation mechanism of iNOS gene. Methods The sequence of iNOS promoter was identified in GenBank by bioinformatics based on the open reading frame(ORF) of iNOS gene and amplified from HepG2 genome by polymerase chain reaction (PCR). The amplified product was subcloned into pCAT3-Basic reporter vector, named as pCAT3-iNOSp. The HepG2 cell line was then transfected with pCAT3-Basic to serve as negative control, and pCAT3-promoter which contains the promoter region of CMV served as the positive control subject, and pCAT3-iNOSp served as the test subject, respectively. The choloraphenical acetyltransferase(CAT)activity was determined by enzyme linked immunosorbent assay(ELISA) kit. The T7 Select human liver cDNA library was biopanned and positive clones were selected. After screening, positive plaque was performed to amplify and PCR products were sequenced. Results The expression of CAT in transfection of pCAT3-PS1TP1p was 4.2 times as higher as pCAT3-Basic plasmid. Sequence analysis was performed in 12 positive plaque, which were the iNOSp binding protein. Conclusion The iNOS gene promoter identified in this study has shown to have transcription activity,and iNOS promoter DNA-binding proteins havs been screened. The results will be useful for further study of the expression and regulation mechanism of iNOS in liver cell.