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1.
BMC Complement Altern Med ; 16: 369, 2016 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-27646829

RESUMO

BACKGROUND: Shenghui soup is a traditional Chinese herbal medicine used in clinic for the treatment of forgetfulness. In order to understanding the prescription principle, the effects of "tonifying qi and strengthening spleen" group (TQSS) including Poria cocos (Schw.) Wolf. and Panax ginseng C.A.Mey and "eliminating phlegm and strengthening intelligence" group (EPSI) composed of Polygala tenuifolia Willd., Acorus calamus L. and Sinapis alba L from the herb complex on neurite growth in PC12 cells, two disassembled prescriptions derived from Shenghui soup and their molecular mechanisms were investigated. METHODS: Firstly, CCK-8 kit was used to detect the impact of the two prescriptions on PC12 cell viability; and Flow cytometry was performed to measure the cell apoptosis when PC12 cells were treated with these drugs. Secondly, the effect of the two prescriptions on the differentiation of PC12 cells was observed. Finally, the mRNA and protein expression levels of GAP-43 were analyzed by RT-PCR and western blot, respectively. RESULTS: "Tonifying qi and strengthening spleen" prescription decreased cell viability in a dose-dependent manner, but had no significant effect on cell apoptosis. Meanwhile, it could improve neurite growth and elevate the mRNA and protein expression level of GAP-43. "Eliminating phlegm and strengthening intelligence" prescription also exerted the similar effects on cell viability and apoptosis. Furthermore, it could also enhance cell neurite growth, with a higher expression level of GAP-43 mRNA and protein. CONCLUSION: "Tonifying qi and strengthening spleen" and "eliminating phlegm and strengthening intelligence" prescriptions from Shenghui soup have a positive effect on neurite growth. Their effects are related to the up-regulating expression of GAP-43.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Proteína GAP-43/metabolismo , Expressão Gênica/efeitos dos fármacos , Neuritos/efeitos dos fármacos , Animais , Proteína GAP-43/genética , Células PC12 , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos
2.
N Engl J Med ; 364(16): 1523-32, 2011 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-21410387

RESUMO

BACKGROUND: Heightened surveillance of acute febrile illness in China since 2009 has led to the identification of a severe fever with thrombocytopenia syndrome (SFTS) with an unknown cause. Infection with Anaplasma phagocytophilum has been suggested as a cause, but the pathogen has not been detected in most patients on laboratory testing. METHODS: We obtained blood samples from patients with the case definition of SFTS in six provinces in China. The blood samples were used to isolate the causal pathogen by inoculation of cell culture and for detection of viral RNA on polymerase-chain-reaction assay. The pathogen was characterized on electron microscopy and nucleic acid sequencing. We used enzyme-linked immunosorbent assay, indirect immunofluorescence assay, and neutralization testing to analyze the level of virus-specific antibody in patients' serum samples. RESULTS: We isolated a novel virus, designated SFTS bunyavirus, from patients who presented with fever, thrombocytopenia, leukocytopenia, and multiorgan dysfunction. RNA sequence analysis revealed that the virus was a newly identified member of the genus phlebovirus in the Bunyaviridae family. Electron-microscopical examination revealed virions with the morphologic characteristics of a bunyavirus. The presence of the virus was confirmed in 171 patients with SFTS from six provinces by detection of viral RNA, specific antibodies to the virus in blood, or both. Serologic assays showed a virus-specific immune response in all 35 pairs of serum samples collected from patients during the acute and convalescent phases of the illness. CONCLUSIONS: A novel phlebovirus was identified in patients with a life-threatening illness associated with fever and thrombocytopenia in China. (Funded by the China Mega-Project for Infectious Diseases and others.).


Assuntos
Infecções por Bunyaviridae/virologia , Doenças Transmissíveis Emergentes/virologia , Orthobunyavirus/isolamento & purificação , Trombocitopenia/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Anticorpos Antivirais/sangue , Infecções por Bunyaviridae/complicações , Infecções por Bunyaviridae/epidemiologia , China/epidemiologia , Doenças Transmissíveis Emergentes/epidemiologia , Feminino , Febre/virologia , Genoma Viral , Humanos , Ixodidae/virologia , Masculino , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Orthobunyavirus/classificação , Orthobunyavirus/genética , Orthobunyavirus/imunologia , Filogenia , RNA Viral/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa
3.
Cancer Lett ; 592: 216937, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38704134

RESUMO

Dysfunctional bone marrow (BM) endothelial progenitor cells (EPCs) with high levels of reactive oxygen species (ROS) are responsible for defective hematopoiesis in poor graft function (PGF) patients with acute leukemia or myelodysplastic neoplasms post-allotransplant. However, the underlying mechanism by which BM EPCs regulate their intracellular ROS levels and the capacity to support hematopoiesis have not been well clarified. Herein, we demonstrated decreased levels of peroxisome proliferator-activated receptor delta (PPARδ), a lipid-activated nuclear receptor, in BM EPCs of PGF patients compared with those with good graft function (GGF). In vitro assays further identified that PPARδ knockdown contributed to reduced and dysfunctional BM EPCs, characterized by the impaired ability to support hematopoiesis, which were restored by PPARδ overexpression. Moreover, GW501516, an agonist of PPARδ, repaired the damaged BM EPCs triggered by 5-fluorouracil (5FU) in vitro and in vivo. Clinically, activation of PPARδ by GW501516 benefited the damaged BM EPCs from PGF patients or acute leukemia patients in complete remission (CR) post-chemotherapy. Mechanistically, we found that increased expression of NADPH oxidases (NOXs), the main ROS-generating enzymes, may lead to elevated ROS level in BM EPCs, and insufficient PPARδ may trigger BM EPC damage via ROS/p53 pathway. Collectively, we found that defective PPARδ contributes to BM EPC dysfunction, whereas activation of PPARδ in BM EPCs improves their hematopoiesis-supporting ability after myelosuppressive therapy, which may provide a potential therapeutic target not only for patients with leukemia but also for those with other cancers.


Assuntos
Células Progenitoras Endoteliais , Hematopoese , PPAR delta , Espécies Reativas de Oxigênio , Adulto , Animais , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Adulto Jovem , Células da Medula Óssea/metabolismo , Células da Medula Óssea/efeitos dos fármacos , Células Progenitoras Endoteliais/metabolismo , Células Progenitoras Endoteliais/efeitos dos fármacos , Fluoruracila/farmacologia , Hematopoese/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Síndromes Mielodisplásicas/patologia , Síndromes Mielodisplásicas/metabolismo , Síndromes Mielodisplásicas/tratamento farmacológico , NADPH Oxidases/metabolismo , PPAR delta/metabolismo , PPAR delta/genética , Espécies Reativas de Oxigênio/metabolismo , Tiazóis/farmacologia , Proteína Supressora de Tumor p53/metabolismo
4.
J Infect Dis ; 206(7): 1095-102, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22850122

RESUMO

BACKGROUND: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by the SFTS virus (SFTSV) with an average fatality rate of 12%. The clinical factors for death in SFTS patients remain unclear. METHODS: Clinical features and laboratory parameters were dynamically collected for 11 fatal and 48 non-fatal SFTS cases. Univariate logistic regression was used to evaluate the risk factors associated with death. RESULTS: Dynamic tracking of laboratory parameters revealed that during the initial fever stage, the viral load was comparable for the patients who survived as well as the ones that died. Then in the second stage when multi-organ dysfunction occurred, from 7-13 days after disease onset, the viral load decreased in survivors but it remained high in the patients that died. The key risk factors that contributed to patient death were elevated serum aspartate aminotransferase, lactate dehydrogenase, creatine kinase, and creatine kinase fraction, as well as the appearance of CNS (central nervous system) symptoms, hemorrhagic manifestation, disseminated intravascular coagulation, and multi-organ failure. All clinical markers reverted to normal in the convalescent stage for SFTS patients who survived. CONCLUSIONS: We identified a period of 7-13 days after the onset of illness as the critical stage in SFTS progression. A sustained serum viral load may indicate that disease conditions will worsen and lead to death.


Assuntos
Infecções por Bunyaviridae/mortalidade , Phlebovirus/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Contagem de Células Sanguíneas , Infecções por Bunyaviridae/sangue , Infecções por Bunyaviridae/patologia , Feminino , Interações Hospedeiro-Patógeno , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Tromboplastina Parcial , Fatores de Risco , Carga Viral
5.
Sci China Life Sci ; 66(11): 2553-2570, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37289327

RESUMO

Aplastic anemia (AA) is a life-threatening disease characterized by bone marrow (BM) failure and pancytopenia. As an important component of the BM microenvironment, endothelial cells (ECs) play a crucial role in supporting hematopoiesis and regulating immunity. However, whether impaired BM ECs are involved in the occurrence of AA and whether repairing BM ECs could improve hematopoiesis and immune status in AA remain unknown. In this study, a classical AA mouse model and VE-cadherin blocking antibody that could antagonize the function of ECs were used to validate the role of BM ECs in the occurrence of AA. N-acetyl-L-cysteine (NAC, a reactive oxygen species scavenger) or exogenous EC infusion was administered to AA mice. Furthermore, the frequency and functions of BM ECs from AA patients and healthy donors were evaluated. BM ECs from AA patients were treated with NAC in vitro, and then the functions of BM ECs were evaluated. We found that BM ECs were significantly decreased and damaged in AA mice. Hematopoietic failure and immune imbalance became more severe when the function of BM ECs was antagonized, whereas NAC or EC infusion improved hematopoietic and immunological status by repairing BM ECs in AA mice. Consistently, BM ECs in AA patients were decreased and dysfunctional. Furthermore, dysfunctional BM ECs in AA patients led to their impaired ability to support hematopoiesis and dysregulate T cell differentiation toward proinflammatory phenotypes, which could be repaired by NAC in vitro. The reactive oxygen species pathway was activated, and hematopoiesis- and immune-related signaling pathways were enriched in BM ECs of AA patients. In conclusion, our data indicate that dysfunctional BM ECs with impaired hematopoiesis-supporting and immunomodulatory abilities are involved in the occurrence of AA, suggesting that repairing dysfunctional BM ECs may be a potential therapeutic approach for AA patients.


Assuntos
Anemia Aplástica , Humanos , Animais , Camundongos , Anemia Aplástica/terapia , Medula Óssea , Células Endoteliais/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Células da Medula Óssea/metabolismo
6.
Curr Mol Med ; 22(9): 826-834, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34872475

RESUMO

AIM: To investigate the effects of PAXT mutations on tumor immunity. BACKGROUND: Loss of function of PAX5 plays a key role in the PAX5 mutation tumor. OBJECTIVE: PAX5 haploinsufficiency promoting tumorigenesis is related to immune escape, but there was no report about mechanisms of PAX5 mutation inducing tumor immunological escape. METHODS: We constructed the PAX5 haplodeletion A20 cell lines using gene-editing technology, built allografted A20 tumor models and evaluated the effect of PAX5 haplodeletion on T cells and chemokines in the tumor microenvironment (TME). RESULTS: Our results from different methods indicated percentages of CD3+ CD4+ T cells and CD3+ CD8+ T cells in TME of PAX5 haplodeletion clones decreased significantly compared with that of PAX5 wild type control. Several chemokines, such as Ccl2, Ccl4, Cxcl9 and Cxcl10, in TME of PAX5. CONCLUSION: Our study showed that PAX5 haploinsufficiency induced low T cell infiltration in TME using decreased chemokines.


Assuntos
Neoplasias , Microambiente Tumoral , Linfócitos T CD8-Positivos , Quimiocinas/genética , Quimiocinas/metabolismo , Haploinsuficiência , Humanos , Neoplasias/genética , Fator de Transcrição PAX5/genética , Linfócitos T/metabolismo , Microambiente Tumoral/genética
7.
Cancer Treat Res Commun ; 28: 100437, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34425470

RESUMO

PURPOSE: PAX5 haploinsufficiency promoting tumorigenesis is related to immune escape. But the mechanisms of PAX5 mutations inducing tumor immune escape have not been clarified. Our aim was to study how PAX5 haploinsufficiency influences effector CD8 + T cells in tumor microenvironment. METHODS: We estimated the proportions of 22 immune cell types and the expressions of immune inhibitory-related molecules based on gene expression profiles (GEPs) from children's B- acute lymphoblastic leukemia(B-ALL) with PAX5 mutations by CIBERSORT, an established algorithm. We constructed the PAX5 haplodeletion A20 cell lines, built allografted A20 tumor models and evaluated the effect of PAX5 haplodeletion on immune inhibitory-related molecules in the tumor microenvironment (TME). RESULTS: Our results indicated the percentages of T cells in bone marrow of children's B-ALL with PAX5 mutations were not statistically different from that in bone marrow of B-ALL without PAX5 mutations, except for T follicular helper (Tfh) cells. But a variety of up-regulated immune inhibitory-related molecules in bone marrow of children's B- ALL with PAX5 mutations were identified. By different approaches, we found that several immune inhibitory-related molecules of CD8+ T cells in TME of PAX5 haplodeletion clones such as TIM3, NR4A1 and BATF, were increased significantly compared with that of PAX5 wild type control. The IFN-ɤ of CD8+ T cells in TME of PAX5 haplodeletion tumors was decreased significantly compared with that of PAX5 wild type control. CONCLUSION: Our study showed that PAX5 haploinsufficiency induced CD8+ T cells dysfunction or exhaustion by high expression of TIM3, NR4A1 and BATF in the CD8+ T cells of TME.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Haploinsuficiência/imunologia , Fator de Transcrição PAX5/imunologia , Evasão Tumoral/imunologia , Humanos
8.
Viruses ; 13(10)2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34696477

RESUMO

Severe fever with thrombocytopenia syndrome virus (SFTSV) is an emerging tick-borne bunyavirus in Asia that causes severe disease. Despite its clinical importance, treatment options for SFTSV infection remains limited. The SFTSV glycoprotein Gn plays a major role in mediating virus entry into host cells and is therefore a potential antiviral target. In this study, we employed an in silico structure-based strategy to design novel cyclic antiviral peptides that target the SFTSV glycoprotein Gn. Among the cyclic peptides, HKU-P1 potently neutralizes the SFTSV virion. Combinatorial treatment with HKU-P1 and the broad-spectrum viral RNA-dependent RNA polymerase inhibitor favipiravir exhibited synergistic antiviral effects in vitro. The in silico peptide design platform in this study may facilitate the generation of novel antiviral peptides for other emerging viruses.


Assuntos
Peptídeos/farmacologia , Phlebovirus/efeitos dos fármacos , Febre Grave com Síndrome de Trombocitopenia/tratamento farmacológico , Antivirais/farmacologia , Infecções por Bunyaviridae/virologia , Linhagem Celular , Linhagem Celular Tumoral , Simulação por Computador , Hong Kong , Humanos , Orthobunyavirus/patogenicidade , Phlebovirus/patogenicidade , Febre Grave com Síndrome de Trombocitopenia/metabolismo , Febre Grave com Síndrome de Trombocitopenia/virologia , Trombocitopenia/virologia , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo , Internalização do Vírus/efeitos dos fármacos
9.
Ann Med ; 52(5): 233-238, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32323584

RESUMO

Objective: To analyze the clinical and biological significance of the acute promyelocytic leukemia (APL) whose PML-RARa transcripts increased after induction therapy.Methods: We analyzed 9 cases of APL whose PML-RARa transcripts increased after induction treatment and compare them with APL whose PML-RARa transcripts decreased.Results: The only factor affecting increased PML-RARa transcripts was the induction protocol. The cases of increased PML-RARa transcripts received induction treatment mainly based on ATRA and ATO. The evaluation of bone marrow aspirate cytology showed that the cell percentage from myelocyte to segmented neutrophil of the patients with increased PML-RARa transcripts was significantly higher than that of the patients with decreased PML-RARa transcripts. In the follow-up, MRD in 9 cases was consistently negative.Conclusions: Our studies showed the increased PML-RARa transcripts after induction treatment had different clinical significance from the decreased PML-RARa transcripts.


Assuntos
Leucemia Promielocítica Aguda/genética , Proteínas de Fusão Oncogênica/metabolismo , Adolescente , Adulto , Idoso , Medula Óssea/patologia , Estudos de Casos e Controles , Feminino , Humanos , Quimioterapia de Indução/métodos , Leucemia Promielocítica Aguda/tratamento farmacológico , Leucemia Promielocítica Aguda/patologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Biomed Environ Sci ; 32(5): 363-370, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31217053

RESUMO

OBJECTIVE: People in Western Africa suffer greatly from febrile jaundice, which is caused by a variety of pathogens. However, yellow fever virus (YFV) is the only pathogen under surveillance in Sierra Leone owing to the undeveloped medical and public health system there. Most of the results of YFV identification are negative. Elucidation of the pathogen spectrum is required to reduce the prevalence of febrile jaundice. METHODS: In the present study, we used Ion Torrent semiconductor sequencing to profile the pathogen spectrum in archived YFV-negative sera from 96 patients in Sierra Leone who presented with unexplained febrile jaundice. RESULTS: The most frequently identified sequencing reads belonged to the following pathogens: cytomegalovirus (89.58%), Epstein-Barr virus (55.21%), hepatitis C virus (34.38%), rhinovirus (28.13%), hepatitis A virus (20.83%), coxsackievirus (10.42%), Ebola virus (8.33%), hepatitis E virus (8.33%), lyssavirus (4.17%), leptospirosis (4.17%), chikungunya virus (2.08%), Crimean-Congo hemorrhagic fever virus (1.04%), and hepatitis B virus (1.04%). CONCLUSION: The distribution of sequencing reads suggests a broader spectrum of pathogens for consideration in clinical diagnostics and epidemiological surveillance in Sierra Leone.


Assuntos
Febre/virologia , Icterícia/virologia , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Febre/epidemiologia , Humanos , Icterícia/epidemiologia , Masculino , Análise de Sequência , Serra Leoa/epidemiologia , Adulto Jovem
11.
Nucleic Acids Res ; 34(8): e62, 2006 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-16682441

RESUMO

Immuno-PCR (IPCR) is a powerful detection technology in immunological study and clinical diagnosis due to its ultrasensitivity. Here we introduce a new strategy termed phage display mediated immuno-PCR (PD-IPCR). Instead of utilization of monoclonal antibody (mAb) and chemically bond DNA that required in the conventional IPCR, a recombinant phage particle is applied as a ready reagent for IPCR experiment. The surface displayed single chain variable fragment (scFv) and phage DNA themselves can directly serve as detection antibody and PCR template, respectively. The aim of the design is to overcome shortcoming of low detection sensitivity of scFv so as to largely facilitate the real application of scFv in immunoassay. The idea has been demonstrated by applying hantaan virus nucleocapsid protein (NP) and prion protein (PrP) as detection targets in three experimental protocols (indirect, sandwich and real-time PD-IPCR assays). The detection sensitivity was increased 1000- to 10,000-folds compared with conventional enzyme-linked immunosorbent assays (ELISAs). This proof-of-concept study may serve as a new model to develop an easy to operate, low cost and ultrasensitive immunoassay method for broad applications.


Assuntos
Imunoensaio/métodos , Região Variável de Imunoglobulina , Biblioteca de Peptídeos , Reação em Cadeia da Polimerase/métodos , Proteínas do Capsídeo/análise , Proteínas do Capsídeo/imunologia , Ensaio de Imunoadsorção Enzimática , Príons/análise , Príons/imunologia , Proteínas do Core Viral/análise , Proteínas do Core Viral/imunologia
12.
Biomed Environ Sci ; 21(5): 372-80, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19133610

RESUMO

OBJECTIVE: To study the passive immunization with human monoclonal antibodies as for prophylaxis of human cytomegalovirus (HCMV) infection. METHODS: Fab monoclonal antibodies to HCMV were recovered by repertoire cloning of mRNA from a HCMV infected individual. Antigen binding specificity, CDR sequence of V(H) and V(L) and neutralizing activity on HCMV AD169 stain were analyzed in vitro. The light and heavy chain Fd fragment genes of Fab antibodies were further cloned into a recombinant baculovirus expression vector pAC-kappa-Fc to express intact IgG. Secreted products were purified with affinity chromatography using protein G. RESULTS: SDS-PAGE and Western blot confirmed the expression of the intact IgG. Immuno-blotting and -precipitation were used to identify HCMV proteins. One Fab monoclonal antibody recognized a conformational HCMV protein. CONCLUSION: IgG antibodies can neutralize the HCMV AD169 strain efficiently at a titer of 2.5 microg/mL and may prove valuable for passive immunoprophylaxis against HCMV infection in humans.


Assuntos
Citomegalovirus/imunologia , Imunoglobulina G/imunologia , Proteínas Recombinantes/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Clonagem Molecular , DNA Viral/genética , Genes Virais , Humanos , Immunoblotting , Imunoprecipitação , Insetos , Dados de Sequência Molecular , Biblioteca de Peptídeos
13.
Infect Dis Poverty ; 5(1): 62, 2016 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-27333890

RESUMO

BACKGROUND: The outbreak of Ebola virus disease (EVD) in West Africa between 2014 and 2015 was the largest EDV epidemic since the identification of Ebola virus (EBOV) in 1976, and the countries most strongly affected were Sierra Leone, Guinea, and Liberia. FINDINGS: The Sierra Leone-China Friendship Biological Safety Laboratory (SLE-CHN Biosafety Lab), a fixed Biosafety Level 3 laboratory in the capital city of Sierra Leone, was established by the Chinese government and has been active in EBOV detection since 11 March 2015. Complete management and program documents were created for the SLE-CHN Biosafety Lab, and it was divided into four zones (the green, yellow, brown, and red zones) based on the risk assessment. Different types of safe and appropriate personnel protection equipment (PPE) are used in different zones of the laboratory, and it fully meets the Biosafety Level 3 laboratory standards of the World Health Organization. CONCLUSION: Good preparedness, comprehensive risk assessment and operation documents, appropriate PPE, effective monitoring and intensive training, together with well-designed and reasonable laboratory sectioning are essential for guaranteeing biosafety.


Assuntos
Ebolavirus/fisiologia , Doença pelo Vírus Ebola/virologia , Laboratórios/normas , Segurança/normas , Serra Leoa
14.
Biomed Environ Sci ; 18(6): 363-74, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16544518

RESUMO

OBJECTIVE: To develop a specific SARS virus-targeted antibody preparation for emergent prophylaxis and treatment of SARS virus infection. METHODS: By using phage display technology, we constructed a naive antibody library from convalescent SARS patient lymphocytes. To obtain the neutralizing antibody to SARS virus surface proteins, the library panning procedure was performed on purified SARS virions and the specific Fab antibody clones were enriched by four rounds of repeated panning procedure and screened by highthroughput selection. The selected Fab antibodies expressed in the periplasma of E. coli were soluble and further purified and tested for their binding properties and antiviral function to SARS virus. The functional Fab antibodies were converted to full human IgG antibodies with recombinant baculovirus/insect cell systems and their neutralizing activities were further determined. RESULTS: After four rounds of the panning, a number of SARS-CoV virus-targeted human recombinant Fab antibodies were isolated from the SARS patient antibody library. Most of these were identified to recognize both natural and recombinant SARS spike (S) proteins, two Fab antibodies were specific for the virus membrane (M) protein, only one bound to SARS-CoV nucleocapsid protein. The SARS-CoV S and M protein-targeted Fab or IgG antibodies showed significant neutralizing activities in cytopathic effect (CPE) inhibition neutralization test, these antibodies were able to completely neutralize the SARS virus and protect the Vero cells from CPE after virus infection. However, the N protein-targeted Fab or IgG antibodies failed to neutralize the virus. In addition, the SARS N protein-targeted human Fab antibody reacted with the denatured N proteins, whereas none of the S and M protein specific neutralizing antibodies did. These results suggested that the S and M protein-specific neutralizing antibodies could recognize conformational epitopes which might be involved in the binding of virions to cellular receptors and the fusion activity of the virus. CONCLUSION: The SARS-CoV spike protein and membrane proteins are able to elicite efficient neutralizing antibodies in SARS patients. The neutralizing antibodies we generated in this study may be more promising candidates for prophylaxis and treatment of SARS infection.


Assuntos
Anticorpos Antivirais/imunologia , Glicoproteínas de Membrana/imunologia , Proteínas Recombinantes/imunologia , Síndrome Respiratória Aguda Grave/imunologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/imunologia , Proteínas do Envelope Viral/imunologia , Proteínas da Matriz Viral/imunologia , Sequência de Aminoácidos , Animais , Chlorocebus aethiops , Proteínas M de Coronavírus , Humanos , Testes de Neutralização , Biblioteca de Peptídeos , Ligação Proteica , Engenharia de Proteínas , Síndrome Respiratória Aguda Grave/virologia , Glicoproteína da Espícula de Coronavírus , Células Vero
15.
Bing Du Xue Bao ; 30(4): 387-90, 2014 Jul.
Artigo em Zh | MEDLINE | ID: mdl-25272591

RESUMO

This article aimed to study the antigenicity of nucleocapsid proteins (NPs) in six pathogenic phleboviruses and to provide theoretical evidence for the development of serological diagnostic reagents. NPs of six pathogenic phleboviruses were expressed and purified using a prokaryotic expression system and rabbits were immunized with individual recombinant NPs. Cross-reactions among NPs and rabbit sera were determined by both indirect ELISA and Western blotting analyses, and the sera titer was determined by indirect ELISA. Furthermore, sera from SFTS patients were also detected by each recombinant NP as a coating antigen using indirect ELISA. The cross-reactions and the sera titer were subsequently determined. Both the concentration and purity of recombinant NPs of six pathogenic phleboviruses met the standards for immunization and detection. The results of indirect ELISA and Western blotting showed that each anti-phlebovirus NP rabbit immune serum had potential serological cross-reactivity with the other five virus NP antigens. Furthermore, the sera from SFTS patients also had cross-reactivity with the other five NP antigens to a certain extent. Our preliminary study evaluated the antigenicity and immune reactivity of six pathogenic phleboviruses NPs and laid the foundation for the development of diagnostic reagents.


Assuntos
Anticorpos Antivirais/imunologia , Proteínas do Nucleocapsídeo/imunologia , Febre por Flebótomos/virologia , Phlebovirus/imunologia , Animais , Antígenos Virais/genética , Antígenos Virais/imunologia , Reações Cruzadas , Humanos , Proteínas do Nucleocapsídeo/genética , Febre por Flebótomos/diagnóstico , Febre por Flebótomos/imunologia , Phlebovirus/classificação , Phlebovirus/genética , Phlebovirus/isolamento & purificação , Coelhos
16.
Bing Du Xue Bao ; 30(6): 599-604, 2014 Nov.
Artigo em Zh | MEDLINE | ID: mdl-25868272

RESUMO

To establish a MacELISA method for the detection of IgM antibodies against Chikungunya virus (CHIKV), we prepared virus like particle (VLP) antigens of CHIKV using the whole structural protein C-E3-E2-6K-E1 encoding gene with a baculovirus expression system in Sf9 insect cells. The VLPs were purified and used to immunize Kunming mice. Then, polyclonal antibodies were purified from the samples of ascites with a protein G HiTrap SP column and labeled with horseradish peroxidase. A MacELISA method for the detection of IgM antibodies against CHIKV was assembled with goat anti-human IgM antibody, VLP antigens and an enzyme-labeled polyclonal antibody. The results were evaluated with a serum panel containing serum samples from laboratory-confirmed CHIK, HFRS patients, healthy donors, and commercially available CHIKV IgM as a quality control. It was shown that the MacELISA had a specificity of 99% (99/100), the coefficients of variation (CoV) within a plate were <10%, and the CoV of different ELISA plates in terms of the plate variation coefficient was <15%. A comparative analysis was performed to compare the current method against a commercial CHIKV IgM antibody detection kit for IIFA-IgM. The detection limit of MacELISA was significantly lower than that of the IIFA-IgM commercial kit (P< 0.0001). Here, we demonstrate that the VLP-based MacELISA is a promising tool for the early diagnosis and epidemiological investigation of CHIKV infection, with a high level of sensitivity and specificity for the detection of IgM antibodies against CHIKV.


Assuntos
Anticorpos Antivirais/sangue , Febre de Chikungunya/diagnóstico , Vírus Chikungunya/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Imunoglobulina M/sangue , Animais , Febre de Chikungunya/sangue , Febre de Chikungunya/virologia , Vírus Chikungunya/isolamento & purificação , Humanos , Camundongos
17.
Bing Du Xue Bao ; 30(3): 221-5, 2014 May.
Artigo em Zh | MEDLINE | ID: mdl-25118374

RESUMO

To evaluate the adjuvant effect of recombinant enterovirus 71 (EV71) subunit vaccine formulated with chitosan, rabbits were orally immunized with recombinant VP1 (rVP1) or rVP1 mixed with chitosan adjuvant. Levels of virus-specific IgG and IgA antibodies in sera, mucosal wash buffer (intestine, nasal cavity, and lung), and feces were determined by indirect enzyme-linked immunosorbent assay (ELISA). The titers of neutralizing antibodies against EV71 were determined using cytopathic effect-based neutralizing assay, and levels of cytokines (IFN-gamma and IL-4) secreted from in vitro-cultured rabbit splenic lymphocytes under antigen stimulation were also determined by ELISA. Results showed that immunization with rVP1 alone could only induce low levels of serum IgG and mucosal IgA, while rVP1 combined with chitosan adjuvant were able to induce significantly higher levels of antibodies, rVP1 can only induce neutralizing antibodies when used in combination with chitosan. Levels of IFN-gamma and IL-4 in the group immunized with rVP1 plus chitosan were significantly higher than those in the group immunized with rVP1 only or those in the control groups. Our study lays the foundation for development of oral VP1 vaccine against EV71 infection.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Quitosana/imunologia , Enterovirus Humano A/imunologia , Infecções por Enterovirus/imunologia , Infecções por Enterovirus/virologia , Proteínas Virais/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/imunologia , Quitosana/administração & dosagem , Enterovirus Humano A/genética , Infecções por Enterovirus/prevenção & controle , Feminino , Humanos , Coelhos , Vacinação , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/genética , Vacinas de Subunidades Antigênicas/imunologia , Proteínas Virais/administração & dosagem , Proteínas Virais/genética , Vacinas Virais/administração & dosagem , Vacinas Virais/genética
18.
Bing Du Xue Bao ; 30(3): 233-7, 2014 May.
Artigo em Zh | MEDLINE | ID: mdl-25118376

RESUMO

This study aims to investigate whether the nucleoprotein (NP) of severe fever with thrombocytopenia syndrome virus (SFTSV) can impact the cellular immunity of host cells. Gene segments that encode the NP and non-structural protein (NSs) of SFTSV were inserted into eukaryotic expression vector VR1012. Host proteins that interact with NP and affect immunity were identified with co-immunoprecipitation (IP), SDS-PAGE, mass spectrometry (MS), and Western blot. Co-localization of NP and the identified host proteins was confirmed by confocal microscopy. A 60kD SSA/Ro, a protein related to immunity, interacted with NP, as found by IP and MS. Confocal microscopy showed that NP and SSA/Ro were co-localized in cytoplasm. These results indicated that SFTSV NP may specifically bind to 60kD SSA/Ro and cause a series of immune responses and clinical symptoms.


Assuntos
Infecções por Bunyaviridae/metabolismo , Nucleoproteínas/metabolismo , Phlebovirus/metabolismo , Ribonucleoproteínas/metabolismo , Proteínas Virais/metabolismo , Infecções por Bunyaviridae/genética , Infecções por Bunyaviridae/virologia , Células HEK293 , Humanos , Nucleoproteínas/genética , Phlebovirus/genética , Ligação Proteica , Ribonucleoproteínas/genética , Proteínas Virais/genética
19.
Biomed Res Int ; 2014: 284314, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25506055

RESUMO

Our former studies have suggested that TongLuoJiuNao (TLJN) is clinically efficacious in the treatment of dementia and improving learning and memory in AD models. When Aß aggregated with oligomer, it is known to be able to induce cellular toxicity as well as cognitive impairment. We tested the possibility that TLJN affects the formation of Aß oligomers. In our experiment, TLJN improved cell viability, inhibited LDH release, and promoted the outgrowth of neurites of neurons treated with Aß. Geniposide, the main component of TLJN, could increase the cell viability of SY5Y-APP695sw cells. The cytotoxicity of pretreated Aß with geniposide was decreased in a dose-dependent manner. SDS-PAGE and Western blotting showed that geniposide and TLJN stimulated Aß oligomer assembly. Compared with the control, more and longer fibrils of Aß in the presence of geniposide were observed under electron microscope though the fibrils became less sensitive to thioflavin T staining. In sum, geniposide is able to protect neurons from Aß-induced damage by remodeling Aß.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Medicamentos de Ervas Chinesas/administração & dosagem , Iridoides/administração & dosagem , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/toxicidade , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Humanos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/administração & dosagem , Ratos
20.
Bing Du Xue Bao ; 29(3): 337-41, 2013 May.
Artigo em Zh | MEDLINE | ID: mdl-23905480

RESUMO

Genus Phlebovirus is single negative-strand RNA virus, and belongs to family bunyaviridae. Its genomes have three segments including L, M and S encoding RNA-dependent RNA polymerase, envelope glycoprotein and nucleoprotein respectively. Phlebovirus is arbovirus and can be disseminated by arthropod. More than 70 types of Phlebovirus so far have been reported, and 68 known serotypes are divided into groups Sandfly fever and Uukuniemi, of which a few members are closely related to human diseases. In addition, new emerging viruses of genus Phlebovirus are discovered recently. In this review, the latest research progress in molecular characteristics, epidemiology, diagnosis, treatment and emerging viruses of Phlebovirus is summarized.


Assuntos
Febre por Flebótomos/virologia , Phlebovirus/fisiologia , Animais , Humanos , Febre por Flebótomos/diagnóstico , Febre por Flebótomos/epidemiologia , Febre por Flebótomos/terapia , Phlebovirus/classificação , Phlebovirus/genética , Phlebovirus/isolamento & purificação
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