Jing An

Capital Medical University, Peping, Beijing, China

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Publications (29)68.86 Total impact

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    ABSTRACT: Vaccination is the most effective countermeasure for protecting individuals from Japanese encephalitis virus (JEV) infection. There are two types of JEV vaccines currently used in China: the Vero cell-derived inactivated vaccine and the live attenuated vaccine. In this study, we characterized the immune response and protective efficacy induced in mice by the inactivated vaccine, live attenuated vaccine and the DNA vaccine candidate pCAG-JME, which expresses JEV prM-E proteins. We found that the live attenuated vaccine conferred 100% protection and resulted in the generation of high levels of specific anti-JEV antibodies and cytokines. The pCAG-JME vaccine induced protective immunity as well as the live attenuated vaccine. Unexpectedly, immunization with the inactivated vaccine only induced a limited immune response and partial protection, which may be due to the decreased activity of dendritic cells and the expansion of CD4+CD25+Foxp3+ regulatory T cells observed in these mice. Altogether, our results suggest that the live attenuated vaccine is more effective in providing protection against JEV infection than the inactivated vaccine and that pCAG-JME will be a potential JEV vaccine candidate.
    Vaccine 07/2013; · 3.77 Impact Factor
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    ABSTRACT: The major pathogens of hand, foot and mouth disease (HFMD) in Beijing, China from 2007 to 2009 were identified in this study. A total of 186 HFMD cases were included, and 136 cases (73%) were positive for enterovirus (EV). In 2007, 75% (27/36) were Coxsackievirus A16 (CA16) positive and 19% (7/36) were Enterovirus 71 (EV71) positive cases. However, EV71 was the predominant virus in 2008, when 56% (31/55) of the cases were positive for EV71 and 22% (12/55) were positive for CA16. In 2009, EV71 and CA16, with positive rates of 36% (16/45) and 29% (13/45), respectively, were still the major pathogens of HFMD. Phylogenetic analysis revealed that the dominant genotype of EV71 was C4, with co-circulation of genotype A in 2009. The prevalent cluster of the EV71 subgenotype C4 changed over time. A proposed new sublineage of EV71, C4a-2, was the predominant virus associated with the Beijing and nationwide HFMD outbreaks since 2008 and amino acid substitution, which possibly link to the central nervous system tropism of EV71, was found in genotype A viruses. Persistent surveillance of HFMD-associated pathogens is required for predicting potential emerging viruses and related disease outbreaks.
    PLoS ONE 01/2013; 8(2):e56318. · 3.73 Impact Factor
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    ABSTRACT: The pathogenesis of dengue virus (DV) infection has not been completely defined and change of redox status mediated by depletion of glutathione (GSH) in host cell is a common result of viral infection. Our previous study has demonstrated that DV serotype 2 (DV2) infection alters host intracellular GSH levels, and exogenous GSH inhibits viral production by modulating the activity of NF-κB in HepG2 cells. GSH is the most powerful intracellular antioxidant and involved in viral infections. Thus, this study was to investigate whether DV2 infection can induce alteration in redox balance and effect of GSH on the disease in HepG2 xenografts SCID mice. Our results revealed that mice infected with DV2 showed alterations in oxidative stress by increasing the level of malondialdehyde (MDA), an end product of lipid peroxidation, and GSSG/GSH ratio. DV2-infected mice also showed a decrease in the activity of catalase (CAT) and total superoxide dismutase (T-SOD) in the serum and/or observed organs, especially the liver. Moreover, DV2 infection resulted in elevated serum levels of the cytokines tumor necrosis factor-α and interlukin-6 and obvious histopathological changes in the liver. The administration of exogenous GSH significantly reversed all of the aforementioned pathological changes and prevented significant liver damage. Furthermore, in vitro treatment of HepG2 cells with antioxidants such as GSH inhibited viral entry as well as the production of reactive oxygen species in HepG2 cells. These results suggest that GSH prevents DV2-induced oxidative stress and liver injury in mice by inhibiting proinflammatory cytokine production, and GSH and may be a promising therapeutic agent for prevention of oxidative liver damage during DV infection.
    PLoS ONE 01/2013; 8(1):e55407. · 3.73 Impact Factor
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    ABSTRACT: Dengue is an old disease caused by the mosquito-borne dengue viruses (DENVs), which have four antigenically distinct serotypes (DENV1-4). Infection by any of them can cause dengue fever (DF) and/or a more serious disease, that is, dengue hemorrhagic fever (DHF) or dengue shock syndrome (DSS). In recent decades, incidence of dengue disease has increased 30-fold, putting a third to half of the world's population living in dengue-endemic areas at high infection risk. However, the pathogenesis of the disease is still poorly understood. The virus binding with its host cell is not only a first and critical step in their replication cycle but also a key factor for the pathogenicity. In recent years, there have been significant advances in understanding interactions of DENVs with their target cells such as dendritic cells (DC), macrophages, endothelial cells, and hepatocytes. Although DENVs reportedly attach to a variety of receptors on these cells, consensus DENV receptors have not been defined. In this review, we summarize receptors for DENVs on different cells identified in recent years.
    The Scientific World Journal 01/2013; 2013:684690. · 1.73 Impact Factor
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    ABSTRACT: Public health is still seriously threatened by dengue virus (DENV) and no vaccine against DENV is yet available for clinical use till now. In this study, DNA vaccine candidates encoding DENV serotype 2 (DENV-2) prM/E (premembrane and envelope proteins) and NS1 (non-structural 1 protein) with or without a gene adjuvant, granulocyte-macrophage colony-stimulating factor (GM-CSF), were evaluated in the aspects of immunity and protective efficacy in mice. We constructed three plasmids, pCAG-prM/E (which only expressed DENV2 prM/E), pCAG-prM/E/NS1 (which only expressed DENV2 prM/E/NS1) and pCAG-DG (which co-expressed DENV2 prM/E/NS1 and GM-CSF). The expressions of the recombined plasmids were analyzed by immuno-staining in Vero cells. Antibody responses and neutralization activity of the sera from the mice were assayed by ELISA and plaque reduction neutralization test after immunization with the plasmids. Immunized BALB/c mice were intracerebrally challenged with DENV2 to evaluate protective efficacy of the plasmids. The recombinant plasmids could be efficiently expressed in Vero cells and induced different levels of specific anti-DENV2 immune responses. The immunized mice were partially protected. The highest survival rate was observed in the pCAG-DG group although the anti-DENV2 titer and neutralization antibody titer were not the highest among the three groups. Our data suggested that pCAG-DG offered better protection against DENV2 infection.
    Molecular Immunology 12/2012; 54(2):109-114. · 2.65 Impact Factor
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    ABSTRACT: The activation of hepatic stellate cells (HSCs) is closely associated with liver fibrosis in chronic hepatitis B virus (HBV) infection. However, the molecular mechanisms leading to HSC activation remain unclear. It has been reported that the platelet-derived growth factor-B (PDGF-B)/PDGF receptor-β (PDGFR-β) signaling pathway is involved in this process. Thus, we investigated whether HBV and its protein contribute to HSC proliferation by the PDGF-B/PDGFR-β signaling pathway. HBV particles were purified from the supernatant of HepG2.2.15 cells by ultracentrifugation and the cell lines carrying HBV preS, e, c or x genes were obtained. After incubation with HBV particles or co-cultured with the cell lines expressed in the viral protein, the proliferation of LX-2 cells, an HSC cell line, were detected by flow cyto-metry and real-time PCR and the expression of molecules related to the PDGF-B/PDGFR-β signaling pathway were further measured. Our results indicated that HBV particles, c and x proteins promoted LX-2 proliferation and increased the mRNA levels of PDGF-B, PDGFR-β, collagen-I and α-smooth muscle actin (α-SMA), as well as the phosphorylation of PDGFR-β; however, the expression protein levels of PDGF-B and PDGFR-β remained unchanged. In conclusion, HBV particles and HBV c and x proteins promote HSC proliferation and fibrogenesis in vitro and the PDGF-B/PDGFR-β signaling pathway is important in this process.
    International Journal of Molecular Medicine 10/2012; · 1.96 Impact Factor
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    ABSTRACT: To investigate the adjuvant effect of granulocyte macrophage colony stimulating factor (GM-CSF) in Flaviviridae virus DNA vaccines. After DNA immunization, the antibody levels of serum from mice were detected by ELISA and indirect immunofluorescence assay. Co-immunization of GM-CSF suppressed the immune responses induced by DV1 and DV2 candidate vaccines whereas enhanced the immune response induced by HCV C and E1 DNA vaccines. As genetic adjuvant for DNA vaccines, GM-CSF might display complex diversity on the immune responses: an augmentation or suppression due to different immunogens. Therefore, GM-CSF should be used with some cautions in clinic.
    Bing du xue bao = Chinese journal of virology / [bian ji, Bing du xue bao bian ji wei yuan hui] 05/2012; 28(3):207-12.
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    ABSTRACT: As a potential cytokine adjuvant of DNA vaccines, granulocyte-macrophage colony-stimulating factor (GM-CSF) has received considerable attention due to its essential role in the recruitment of antigen-presenting cells, differentiation and maturation of dendritic cells. However, in our recent study of a Japanese encephalitis virus (JEV) DNA vaccine, co-inoculation of a GM-CSF plasmid dramatically suppressed the specific IgG response and resulted in decreased protection against JEV challenge. It is known that GM-CSF has been used in clinic to treat neutropenia for repopulating myeloid cells, and as an adjuvant in vaccine studies; it has shown various effects on the immune response. Therefore, in this study, we characterized the suppressive effects on the immune response to a JEV DNA vaccine by the co-administration of the GM-CSF-expressing plasmid and clarified the underlying mechanisms of the suppression in mice. Our results demonstrated that co-immunization with GM-CSF caused a substantial dampening of the vaccine-induced antibody responses. The suppressive effect was dose- and timing-dependent and likely related to the immunogenicity of the antigen. The suppression was associated with the induction of immature dendritic cells and the expansion of regulatory T cells but not myeloid-derived suppressor cells. Collectively, our findings not only provide valuable information for the application of GM-CSF in clinic and using as a vaccine adjuvant but also offer further insight into the understanding of the complex roles of GM-CSF.
    PLoS ONE 01/2012; 7(4):e34602. · 3.73 Impact Factor
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    ABSTRACT: Waardenburg syndrome (WS) is an auditory-pigmentary disorder resulting from melanocyte defects, with varying combinations of sensorineural hearing loss and abnormal pigmentation of the hair, skin, and inner ear. WS is classified into four subtypes (WS1-WS4) based on additional symptoms. PAX3 and SOX10 are two transcription factors that can activate the expression of microphthalmia-associated transcription factor (MITF), a critical transcription factor for melanocyte development. Mutations of PAX3 are associated with WS1 and WS3, while mutations of SOX10 cause WS2 and WS4. Recently, we identified some novel WS-associated mutations in PAX3 and SOX10 in a cohort of Chinese WS patients. Here, we further identified an E248fsX30 SOX10 mutation in a family of WS2. We analyzed the subcellular distribution, expression and in vitro activity of two PAX3 mutations (p.H80D, p.H186fsX5) and four SOX10 mutations (p.E248fsX30, p.G37fsX58, p.G38fsX69 and p.R43X). Except H80D PAX3, which retained partial activity, the other mutants were unable to activate MITF promoter. The H80D PAX3 and E248fsX30 SOX10 were localized in the nucleus as wild type (WT) proteins, whereas the other mutant proteins were distributed in both cytoplasm and nucleus. Furthermore, E248fsX30 SOX10 protein retained the DNA-binding activity and showed dominant-negative effect on WT SOX10. However, E248fsX30 SOX10 protein seems to decay faster than the WT one, which may underlie the mild WS2 phenotype caused by this mutation.
    Human Genetics 10/2011; 131(3):491-503. · 4.63 Impact Factor
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    ABSTRACT: Dengue is one of the most important mosquito-borne viral diseases. In past years, although considerable effort has been put into the development of a vaccine, there is currently no licensed dengue vaccine. In this study, we constructed DNA vaccines that carried the prM-E-NS1 genes of dengue virus serotype 1 (DV1) with or without the granulocyte-macrophage colony-stimulating factor (GM-CSF) gene, an attractive DNA vaccine adjuvant. Immunization with the plasmid pCAG-DV1/E/NS1, which expresses viral prM-E-NS1, or the bicistronic plasmid pCAG-DV1-GM, which co-expresses viral prM-E-NS1 and GM-CSF, resulted in long-term IgG response, high levels of splenocyte-secreted interferon-γ and interleukin-2, strong cytotoxic T lymphocyte activity and sufficient protection in the DV1-challenged mice. This suggested that both humoral and cellular immune responses were induced by the immunizations and that they played important roles in protection against the DV1 challenge. Interestingly, the magnitude, quality and protective capacity of the immune responses induced by immunization with pCAG-DV1/E/NS1 or pCAG-DV1-GM seemed stronger than those induced by pCAG-DV1/E (expressing viral prM-E alone). Taken together, we demonstrated that prM/E plus NS1 would be a suitable solution for the development of a DNA vaccine against DV.
    Vaccine 01/2011; 29(4):763-71. · 3.77 Impact Factor
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    ABSTRACT: Ultraviolet radiation A (UVA)-induced oxidative stress is recognized as an important factor in the development of skin carcinogenesis. Resveratrol is demonstrated to possess remarkable antioxidant activity in the organism. The aim of this study was to investigate the protective role of resveratrol in human keratinocytes (HaCaT) against UVA-induced oxidative damage and the possible mechanism of the translocation of NF-E2-related factor-2 (Nrf2) into the nucleus. The HaCaT cells were UVA-irradiated and the effects of resveratrol on cell viability, reactive oxygen species generation and membrane-lipid peroxidation were measured. The proteins and mRNA of Nrf2 and Kelch-like-ECH-associated protein 1 (Keap1) were determined by immunofluorescence staining, Western blot and quantitative PCR, respectively. UVA exposure led to a decrease in viability and an increase in reactive oxygen species generation in HaCaT cells. Resveratrol could effectively increase the viability of HaCaT cells after UVA exposure and protect them from UVA-induced oxidative stress. Moreover, resveratrol increased the level of Nrf2 protein and facilitated Nrf2 accumulation in the nucleus; as a result, the activity of antioxidant enzymes was also upregulated. The main finding was that Keap1 protein, a repressor of Nrf2 in the cytoplasm, was clearly decreased by resveratrol treatment 12h and beyond though the level of Keap1 mRNA still increased. Our results suggest that resveratrol can degrade Keap1 protein and facilitate Nrf2 accumulation in the nucleus, thereby protecting HaCaT cells from UVA-induced oxidative stress. Resveratrol could be a more useful natural medicine for the protection of epidermal cells from UVA-induced damage.
    European journal of pharmacology 10/2010; 650(1):130-7. · 2.59 Impact Factor
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    ABSTRACT: It was reported that a signaling pathway of platelet-derived growth factors (PDGFs) and their receptors (PDGFRs) played a critical role in the developing gut of mice. Overexpression of the PDGFR-alpha gene in gastrointestinal stromal tumors (GISTs) indicated that parts of tumor cells originated from PDGFR-alpha-positive cells, but a more detailed distribution of PDGFR-alpha and possible role in the adult mammalian gut are still unclear. In the present study, we examined the expression of both PDGF-AA and its receptor PDGFR-alpha in the gastrointestinal (GI) tract of adult guinea pigs using western blotting and immunohistochemistry. PDGF-AA-immunoreactive cells were mainly distributed in the mucosal epithelium of the stomach, small intestine, and large intestine. Only a few PDGF-AA-positive cells were seen in the longitudinal muscle layer of the large intestine. In contrast, PDGFR-alpha-positive cells were widely distributed throughout the GI tract, including the lamina propria, muscular layer, and subserosa. Double staining showed that the distribution of the PDGFR-alpha-positive cells in the muscular layer were similar to those of the interstitial cells of Cajal (ICCs), and they were associated with ICCs and enteric nerves, but no double-labeled cells were observed by anti-PDGFR or Kit antibody. It was noted that PDGFR-alpha-positive cells were also stained with a vimentin monoclonal antibody. Based on the double staining and morphological features, we consider the PDGFR-alpha-positive cells belong to a subtype of fibroblast. Our results not only provide a roadmap for understanding the function of the PDGF/PDGFR signaling pathway in both normal adult mammals and during gut injury and repair but also might help in understanding the growth and development of GISTs in the clinic.
    Archiv für Pathologische Anatomie und Physiologie und für Klinische Medicin 09/2010; 457(3):381-8. · 2.68 Impact Factor
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    ABSTRACT: Reduced glutathione (GSH) is the most powerful intracellular antioxidant and also involved in viral infections. The pathogenesis of dengue virus (DV) infection has not been completely clarified. This study investigated the relationship between DV serotype 2 (DV2) infections and host intracellular GSH content. Results showed infection with DV2 resulted in a decrease in intracellular GSH, which caused NF-kappaB activation and increased DV2 production. Supplemental GSH significantly inhibited activation of NF-kappaB, resulting in a decreased production of DV2 in HepG2 cells. Furthermore, high activity of NF-kappaB and increased production of DV2 was observed in HepG2 cells treated with buthionine sulfoximine (BSO), an inhibitor of GSH synthesis. In conclusion, DV2 infection could reduce host intracellular GSH concentration and benefited from this process. Supplemental GSH could inhibit viral production, indicating GSH might be valuable in the prevention and treatment of DV2 infection.
    Biochemical and Biophysical Research Communications 07/2010; 397(3):420-4. · 2.41 Impact Factor
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    ABSTRACT: Increased vascular permeability is a hallmark feature in severe dengue virus (DV) infection, and dysfunction of endothelial cells has been speculated to contribute in the pathogenesis of dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS). Rho-family GTPase Rac1 is a significant element of endothelial barrier function regulation and has been implicated in the regulation of actin remodeling and intercellular junction formation. Yet there is little evidence linking Rac1 GTPase to alteration in endothelial cell function induced by DV infection. Here, we showed that actin is essential for DV serotype 2 (DV2) entry into and release from ECV304 cells, and Rac1 signaling is involved these processes. At early infection, actin cytoskeleton rearranged significantly during 1 hour post infection, and disrupting actin filament dynamics with jasplakinolide or cytochalasin D reduced DV2 entry. DV2 entry induced reduction of Rac1 activity within 1 hour post infection. The expression of dominant-negative forms of Rac1 established that DV2 entry is negatively regulated by Rac1. At late infection, actin drugs also inhibited the DV2 release and induced accumulation of viral proteins in the cytoplasm. Meanwhile, the activity of Rac1 increased significantly with the progression of DV2 infection and was up-regulated in transfected cells expressing E protein. Confocal microscopy showed that DV2 E protein was closely associated with either actin or Rac1 in DV2-infected cells. The interaction between E protein and actin was further confirmed by co-immunoprecipitation assay. These results defined roles for actin integrity in DV2 entry and release, and indicated evidence for the participation of Rac1 signaling pathways in DV2-induced actin reorganizations and E-actin interaction. Our results may provide further insight into the pathogenesis of DHF/DSS.
    PLoS Neglected Tropical Diseases 01/2010; 4(8). · 4.57 Impact Factor
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    ABSTRACT: Japanese encephalitis virus (JEV) is an agent of Japanese encephalitis, and granulocyte-macrophage colony-stimulating factor (GM-CSF) is an attractive DNA vaccine adjuvant for its antigen presentation. In the present study, we have constructed DNA vaccines that carried JEV prM–E–NS1 genes with or without the GM-CSF gene. Immunization with the bicistronic plasmid pCAG-JEGM that co-expresses GM-CSF and viral prM–E–NS1, resulted in the highest IgG response and sufficient protection against virus-challenged BALB/c mice. However, much to our surprise, co-inoculation of the GM-CSF plasmid with the pCAG-JE plasmid expressing viral prM–E–NS1 lead to a low antibody titer and a relatively low survival rate. Moreover, anamnestic antibody-mediated protection played a dominant role in the mice JEV challenge model, according to the enhancement of post-challenge neutralizing antibody titers and further adoptive transfer experiments. Taken together, this study should encourage further development of JEV DNA vaccine strategies and caution against the use of cytokines as an adjuvant.
    Immunology letters 01/2010; 129(1):23-31. · 2.91 Impact Factor
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    ABSTRACT: The pathogenesis of the dengue virus (DV) infection has not been well defined. We have reported that actin and Rab8 are involved in DV2 infection. Myosin Vc (Myo5c) is a novel member of the class V myosins and regulates the actin-mediated membrane trafficking associated with Rab8. In this study, the involvement of Myo5c in the release of DV2 was investigated in HpeG2 cells. Distributions of actin, Myo5c, DV2 and Rab8 were revealed by fluorescent staining. HepG2(Myo5c-tail) cells expressing a dominant-negative mutant of Myo5c were constructed by transfection and were assessed by Western blotting. The viral titers were detected by plaque assay, and the expression of Rab8 was analyzed by flow cytometry. DV2 infection altered the distribution pattern of Myo5c, which might be associated with the depolymerization of actin, though colocalization rates of Myo5c with DV2 or actin were low. Furthermore, the release of DV2, but not the intracellular viral production, was reduced from HepG2(Myo5c-tail) cells. Moreover, Myo5c colocalized with Rab8 and an increase of Rab8 was associated with the decrease of the viral release caused by the Myo5c tail. Our data suggest that Myo5c associated with Rab8 is involved in the release of DV2 from HepG2 cells.
    Intervirology 08/2009; 52(5):258-65. · 1.89 Impact Factor
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    ABSTRACT: To investigate the structure and function of nonstructural (NS) protein 2B of the dengue serotype 2 virus (DV2) during infection, polyclonal antibodies (Abs) against DV2 NS2B were prepared by immunisation with NS2B protein or by DNA immunisation. The full-length NS2B gene was cloned and inserted into the prokaryotic expression vector pQE31, resulting in a vector, named pQE-NS2B, or into the eukaryotic expression vector pCAGGS-P7, resulting in the vector pCAG-NS2B. The pQE-NS2B vector was transfected into Escherichia coli JM109, and recombinant NS2B protein was obtained by Ni(2+)-NTA agarose affinity chromatography. Vero cells transfected with pCAG-NS2B showed that NS2B protein can be expressed in eukaryotic cells. Finally, mice were immunised with the recombinant NS2B protein or pCAG-NS2B. Anti-NS2B sera from the immunised mice could specifically react with DV2 NS2B proteins, as visualised by fluorescence staining and Western blotting. Immunisation with NS2B protein induced a higher titre of the antibody than that induced by DNA immunisation. These data indicate that our antisera against DV2 NS2B can recognise both the natural and denatured NS2B protein. Based on these results, the polyclonal Abs could be used as a tool for studying the role of NS2B in the pathogenesis of DV2.
    Journal of virological methods 06/2009; 163(1):10-6. · 2.13 Impact Factor
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    ABSTRACT: Dengue fever and dengue hemorrhagic fever/dengue shock syndrome are highly infectious diseases caused by dengue virus (DV). Specific monoclonal antibodies (mAbs) against DV are vital for diagnosis, pathological studies, and passive immune therapy. In this study, purified DV serotype 2 (DV2) was used as antigen and BALB/c mice were immunized to induce specific antibodies. We established five hybridoma cell lines, called 78#, 1E7, 7F7, 8F12, and 8H1, respectively, and evaluated them by enzyme-linked immunosorbent assay, indirect immunofluorescence assay, Western blot, plaque reduction neutralization test, and suckling mice protection assay. Lines 78#, 1E7, 7F7, and 8F12 showed a neutralizing effect, and lines 78#, 1E7, 8F12, and 8H1 recognized envelope glycoprotein of DV2. Among them, lines 78# and 8F12 had stronger neutralizing ability in vitro and could protect some suckling mice from virus challenge. Our results demonstrate that immunization with purified virion is efficient for the production of specific neutralizing mAbs against DV2, and these mAbs could be useful tools for studying or treating DV infection.
    Current Microbiology 03/2009; 58(4):326-31. · 1.52 Impact Factor
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    ABSTRACT: Caveolae- and clathrin-mediated endocytosis are major internalization pathways used by several pathogens; however, their distinctive roles in dengue virus (DV) entry have not been addressed. In this study, we compared the involvement of caveolae- and clathrin-mediated endocytosis in the infectious entry of DV serotype 2 (DV2) into human endothelial-like ECV304 cells. Confocal microscopy study on DV2-infected cells showed that viral antigens were co-localized with clathrin heavy chains, epidermal growth factor pathway substrate clone 15 (Eps15), and adaptin-alpha, but not with caveolin-1. Treatment with chlorpromazine, which inhibits clathrin-dependent endocytosis, led to reduced virus entry into cells, whereas treatment with nystatin, a caveolae inhibitory agent, did not. Furthermore, gene silencing of Eps15 resulted in an average of 75% reduced infection of ECV304 cells by DV2. Our results demonstrated that DV2 enters ECV304 cells by clathrin-dependent endocytosis, not by caveolae-dependent endocytosis.
    Canadian Journal of Microbiology 02/2009; 55(2):139-45. · 1.20 Impact Factor
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    ABSTRACT: Dengue fever and dengue hemorrhagic fever/dengue shock syndrome are highly infectious diseases caused by dengue virus (DV). DV non-structural protein 3 (NS3) is known to possess ATPase, helicase, and protease activity that is a constitutive part of the replication complex of DV. In this study, we discuss the cloning, expression, and purification of the DV-2 NS3 protein to immunize mice by intrasplenic injection and then to generate a monoclonal antibody (MAb). One MAb, named 4F5, was obtained and it was specific to NS3 of DV-2. Immunofluorescence show that 4F5 recognizes the native protein in infected ECV304 cells. Likewise, C6/36-infected lysates were used in Western blot analysis, and we observed the specific characteristic band that defines NS3. We conclude that MAb 4F5 may be a useful tool, not only to study the replicative process of DV, but also to generate specific diagnostic tools for DV infection.
    Hybridoma (2005) 01/2009; 27(6):467-71. · 0.33 Impact Factor

Publication Stats

191 Citations
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68.86 Total Impact Points

Institutions

  • 2007–2013
    • Capital Medical University
      • School of Basic Medical Sciences
      Peping, Beijing, China
  • 2010
    • Capital University of Integrative Medicine
      China, Maine, United States
  • 2003–2010
    • Third Military Medical University
      • Department of Microbiology
      Chongqing, Chongqing Shi, China