1.Amplification and Characterization of Bull Semen Infected Naturally with Foot-and-mouth Disease Virus Type Asial by RT-PCR
Junjun SHAO ; Huiyun CHANG ; Tong LIN ; Guozheng CONG ; Junzheng DU ; Jianhong GUO ; Huifang BAO ; Youjun SHANG ; Yamin YANG ; Xiangtao LIU ; Zaixin LIU ; Jixing LIU
Virologica Sinica 2008;23(5):378-382
To investigate the security of semen biologically, 15 bull semen samples were collected (of which 5 exhibited clinical signs of Foot-and-mouth disease) and identified by RT-PCR and virus isolation. The results indicated that the semen of the infected bulls were contaminated by Foot-and-mouth disease virus (FMDV), but FMDV was not detected in semen samples from those bulls not showing clinical signs of Foot-and-mouth disease (FMD). This is the first report of the presence of FMDV in bull semen due to natural infection in China. The analysis of the partial sequence of the VP1 gene showed that the virus strain isolated from semen has 97.9% identity with the virus isolated from vesicular liquid of infected bulls showing typical signs of FMD and belonged to the same gene sub-group.
2.Prokaryotic expression and bioreactivity analysis of a major epitope region of 2C with 3AB within non-structural protein of foot-and-mouth disease virus.
Xiaoli ZHANG ; Meina TIAN ; Zengjun LU ; Yuanfang FU ; Xiaojun MA ; Zaixin LIU ; Qingge XIE
Chinese Journal of Biotechnology 2009;25(1):10-15
In recent years, the potential value of nonstructural protein (NSP) 2C was well documented for distinguishing foot-and-mouth disease virus (FMDV) in infected animals and vaccinated animals. In order to develop a more sensitive approach to detect natural infected FMDV while there is no interact with vaccinated FMDV, we incorporated a major epitope region of 2C with whole 3AB coding region within NSP and expressed in Escherichia coli. We got a 47.6 kD fusion protein named 2C'3AB. The product showed a specific reactivity with FMDV from serum of infected animal by using Western blotting analysis. This suggests that this protein could be applied to distinguish infected FMDV and vaccinated FMDV. We further compared 2C'3AB protein with 3ABC fusion protein, another available protein used for detecting infected FMDV, using indirect ELISA assay. The results showed that 2C'3AB-ELISA had higher sensitivity than that of 3ABC-ELISA for distinguishing infected FMDV and vaccinated FMDV of sera from epidemic region. Therefore, this recombinant protein 2C'3AB is a good candidate protein to develop more sensitive method to differentiate infected FMDV and vaccinated FMDV from vaccinated animals. This finding will increase our capability to check the infectious virus carrier and finally improve FMDV infection control.
Animals
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Antibody Specificity
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Carrier Proteins
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genetics
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immunology
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metabolism
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Epitopes
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immunology
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Escherichia coli
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genetics
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metabolism
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Foot-and-Mouth Disease Virus
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genetics
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Recombinant Fusion Proteins
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genetics
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immunology
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metabolism
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Viral Nonstructural Proteins
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genetics
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immunology
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metabolism
3.Classification and composition change of hospitalized patients with pulmonary hypertension in Xiangya Hospital from 2009 to 2013.
Qiong LIU ; Tianlun YANG ; Zaixin YU
Chinese Journal of Cardiology 2014;42(12):1006-1009
OBJECTIVETo analyze the classification and composition change of hospitalized patients with pulmonary hypertension (PH) in our hospital during recent 5 years.
METHODSThis retrospective analysis was performed for hospitalized patients with PH between January 2009 and November 2013.
RESULTSA total of 1 003 patients diagnosed with PH were included, the PH-to-total discharged patients ratio was 2.30%. Majority PH (682, 68.00%) was originated from congenital heart diseases (CHD-PH), 11.67% (117) from connective tissue diseases, 11.26% (113) from valvular heart diseases, 4.99% (50) from idiopathic, 2.00% (20) from respiratory diseases. The CHD-PH decreased gradually (P = 0.041) while the VHD-PH increased gradually (P = 0.017) , especially in 2013. The percentage of right cardiac catheterization examination in this PH cohort was 18.64% (187/1 003). Excluding CHD-PAH and VHD-PH, the ratio of right cardiac catheterization examination in PH patients was 40.38% (84/208). Correct PH diagnosis by echocardiography was 74.00% (187/253) according to right cardiac catheterization examination. A total of 186 PH patients received pulmonary vascular-targeted medication, 84.90% patients were treated with mono-therapy.
CONCLUSIONThe clinical data from Xiangya hospital in 2009-2013 shows a stable composition of hospitalized patients with PH, the rate of right cardiac catheterization in these patients is low and the rate of specific target treatment of PH is high (mostly mono-therapy) excluding CHD-PAH and VHD-PH patients.
Cardiac Catheterization ; Echocardiography ; Heart Defects, Congenital ; Hospitalization ; Humans ; Hypertension, Pulmonary ; complications ; etiology ; therapy ; Retrospective Studies
4.Enhanced immune response of a novel T-cell immunogen in vaccine for foot-and-mouth disease.
Qing ZHAO ; Pu SUN ; Zaixin LIU ; Pinghua LI ; Huifang BAO ; Yimei CAO ; Xingwen BAI ; Yuanfang FU ; Zengjun LU ; Dong LI
Chinese Journal of Biotechnology 2011;27(9):1281-1291
We investigated the enhanced immune response of a recombinant T cell immunogen as an effective cellular immune adjuvant. The T cell immunogen named TI contained several T cell epitopes from the VP1, VP4, 3A and 3D proteins of foot-and-mouth disease virus (FMDV) and two pan-T helper (T(H)) cell sites to broaden the immunogenicity of the protein. Meanwhile, another fusion protein named OA-VP1 was expressed in bacteria, which contained two VP1 proteins of O and Asia1 type FMDV. Mice were vaccinated with commercially inactivated vaccine or OA-VP1 protein with or without the TI immunogen. The results show that mice inoculated with inactivated vaccine or OA-VP1 protein supplemented with TI immunogen produced significantly higher level of neutralizing antibodies (P < 0.01 or P < 0.05) than the mice only inoculated with inactivated vaccine or OA-VP1 protein by microneutralization assay. An obvious increase in T cell number by flow cytometric analysis and significantly higher concentration of IFN-gamma secreted in culture media of spleen lymphocytes were observed in groups supplemented with TI immunogen (P < 0.01). TI immunogen was an effective stimulator for humoral and cellular immunity and could help improve the immunogenicity of inactivated vaccine or protein subunit vaccine.
Adjuvants, Immunologic
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pharmacology
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Animals
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Capsid Proteins
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genetics
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immunology
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Epitopes, T-Lymphocyte
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genetics
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immunology
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Foot-and-Mouth Disease
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immunology
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prevention & control
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virology
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Foot-and-Mouth Disease Virus
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immunology
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Immunization
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Mice
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Viral Vaccines
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genetics
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immunology
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pharmacology
5.Development of a sandwich ELISA for detecting 3AB non-structural protein of foot-and-mouth disease virus.
Yuanfang FU ; Wei HE ; Pu SUN ; Lin YANG ; Huifang BAO ; Yimei CAO ; Xingwen BAI ; Pinghua LI ; Dong LI ; Yingli CHEN ; Lei LIU ; Zengjun LU ; Zaixin LIU
Chinese Journal of Biotechnology 2020;36(11):2357-2366
Antigenic purity is important for quality control of the foot-and-mouth (FMD) whole virus inactivated vaccine. The recommended method for evaluation the antigenic purity of FMD vaccine is to check the serum conversion to non-structural protein (NSP) 3AB antibody after 2 to 3 times inoculation of animals with inactivated vaccine. In this study, we developed a quantitative ELISA to detect the amount of residual 3AB in vaccine antigen, to provide a reference to evaluate the antigenic purity of FMD vaccine. Monoclonal antibody (Mab) of NSP 3A and HRP-conjugated Mab of NSP 3B were used to establish a sandwich ELISA to quantify the NSP 3AB in vaccine antigen of FMD. Purified NSP 3AB expressed in Escherichia coli was serially diluted and detected to draw the standard curve. The detectable limit was determined to be the lowest concentration of standard where the ratio of its OD value to OD blank well was not less than 2.0. Results: The OD value was linearly corelated with the concentration of 3AB protein within the range between 4.7 and 600 ng/mL. The correlation coefficient R² is greater than 0.99, and the lowest detectable limit is 4.7 ng/mL. The amount of 3AB protein in non-purified inactivated virus antigen was detected between 9.3 and 200 ng/mL depending on the 12 different virus strains, whereas the amount of 3AB in purified virus antigen was below the lowest detectable limit. The amount of 3AB in 9 batches of commercial FMD vaccine antigens was between 9.0 and 74 ng/mL, whereas it was below the detectable limit in other 24 batches of commercial vaccine antigens. Conclusion: the sandwich ELISA established in this study is specific and sensitive to detect the content of 3AB protein in vaccine antigen of FMD, which will be a useful method for evaluation of the antigenic purity and quality control of FMD inactivated vaccine.
Animals
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Antibodies, Viral
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Enzyme-Linked Immunosorbent Assay
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Foot-and-Mouth Disease/prevention & control*
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Foot-and-Mouth Disease Virus
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Viral Nonstructural Proteins/genetics*
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Viral Vaccines
6.A method for immortalizing swine monoclonal B cells secreting anti-PRRSV antibodies.
Jian WANG ; Jing ZHANG ; Kun LI ; Pu SUN ; Guoxiu LI ; Jiaoyang LI ; Yimei CAO ; Zhixun ZHAO ; Hong YUAN ; Yuanfang FU ; Pinghua LI ; Dong LI ; Zaixin LIU ; Zengjun LU
Chinese Journal of Biotechnology 2022;38(8):2872-2882
Porcine reproductive and respiratory syndrome (PRRS) is a highly contagious disease caused by porcine reproductive and respiratory syndrome virus (PRRSV), which causes great economic losses. At the moment, no effective neutralizing antibody is available for scientific research and treatment. Therefore, developing a method for screening the neutralizing monoclonal antibodies is of great significance for the prevention and treatment of PRRSV and the screening of antigen sites. Monoclonal antibodies have been widely used in the treatment and diagnosis of many human and animal diseases. Therefore, screening effective neutralizing antibodies for different pathogens is an urgent task. Among the methods for monoclonal antibody screening, B cell immortalization is an effective method to obtain neutralizing monoclonal antibody. Specifically, in this study, the bcl-6 and bcl-xl genes were connected by f2a and then the yielded product was ligated to a vector for retrovirus packaging. The swine lymphocytes immunized with PRRSV were infected the yielded mature viruses and cultured in the complete medium containing CD40L and IL21 cytokines. Then, CD21 was used as the marker to screen B cells with the magnetic bead method. Finally, monoclonal B cells were obtained and the secretion of antibodies was tested. The results showed that the plasmid, either being transfected alone or with the packaged plasmids, could be expressed, and that the packaged retrovirus could infect the cells. Moreover, the infected lymphocytes secreted antibodies, so did the screened B cells. Therefore, the method for screening monoclonal antibody against PRRSV was successfully established.
Animals
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Antibodies, Monoclonal
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Antibodies, Neutralizing
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Antibodies, Viral
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Humans
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Porcine Reproductive and Respiratory Syndrome/prevention & control*
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Porcine respiratory and reproductive syndrome virus/genetics*
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Swine