Search

Your search keyword '"Cui, Zhizhong"' showing total 364 results
Start Over Author "Cui, Zhizhong"
364 results on '"Cui, Zhizhong"'

61. Deletion of the meq gene significantly decreases immunosuppression in chickens caused by pathogenic marek's disease virus

Author

Cui Zhizhong, Zhao Peng, Su Shuai, Sun Aijun, Li Yanpeng, and Zhu Hongfei

Subjects
Infectious and parasitic diseases, RC109-216
Abstract

Abstract Background Marek's disease virus (MDV) causes an acute lymphoproliferative disease in chickens, resulting in immunosuppression, which is considered to be an integral aspect of the pathogenesis of Marek's disease (MD). A recent study showed that deletion of the Meq gene resulted in loss of transformation of T-cells in chickens and a Meq-null virus, rMd5ΔMeq, could provide protection superior to CVI988/Rispens. Results In the present study, to investigate whether the Meq-null virus could be a safe vaccine candidate, we constructed a Meq deletion strain, GX0101ΔMeq, by deleting both copies of the Meq gene from a pathogenic MDV, GX0101 strain, which was isolated in China. Pathogenesis experiments showed that the GX0101ΔMeq virus was fully attenuated in specific pathogen-free chickens because none of the infected chickens developed Marek's disease-associated lymphomas. The study also evaluated the effects of GX0101ΔMeq on the immune system in chickens after infection with GX0101ΔMeq virus. Immune system variables, including relative lymphoid organ weight, blood lymphocytes and antibody production following vaccination against AIV and NDV were used to assess the immune status of chickens. Experimental infection with GX0101ΔMeq showed that deletion of the Meq gene significantly decreased immunosuppression in chickens caused by pathogenic MDV. Conclusion These findings suggested that the Meq gene played an important role not only in tumor formation but also in inducing immunosuppressive effects in MDV-infected chickens.

Published
2011
Full Text
View/download PDF

64. Deletion of 1.8-kb mRNA of Marek's disease virus decreases its replication ability but not oncogenicity

Author

Zhu Hongfei, Chen Hongjun, Su Shuai, Wang Jingyan, Li Yanpeng, Sun Aijun, Ding Jiabo, and Cui Zhizhong

Subjects
Infectious and parasitic diseases, RC109-216
Abstract

Abstract Background The 1.8-kb mRNA was reported as one of the oncogenesis-related genes of Marek's disease virus (MDV). In this study, the bacterial artificial chromosome (BAC) clone of a MDV field strain GX0101 was used as the platform to generate mutant MDV to examine the functional roles of 1.8-kb mRNA. Results Based on the BAC clone of GX0101, the 1.8-kb mRNA deletion mutant GX0101Δ(A+C) was constructed. The present experiments indicated that GX0101Δ(A+C) retained a low level of oncogenicity, and it showed a decreased replication capacity in vitro and in vivo when compared with its parent virus, GX0101. Further studies in vitro demonstrated that deletion of 1.8-kb mRNA significantly decreased the transcriptional activity of the bi-directional promoter between 1.8-kb mRNA and pp38 genes of MDV. Conclusion These results suggested that the 1.8-kb mRNA did not directly influence the oncogenesis but related to the replication ability of MDV.

Published
2010
Full Text
View/download PDF

65. Virus-encoded miR-155 ortholog is an important potential regulator but not essential for the development of lymphomas induced by very virulent Marek's disease virus

Author

Ju-Xiong Liu, Xiangchao Cheng, Ke Ding, Le-Le Yu, Zu-Hua Yu, Cui Zhizhong, Bo Hu, Liang-Hu Qu, Gaiping Zhang, Man Teng, Jun Luo, and Aijun Sun

Subjects
Gene Expression Regulation, Viral, Lymphoma, Virulence, Mutagenesis (molecular biology technique), Pathogenesis, Oncogenicity, medicine.disease_cause, Virus, miR-155, MDV, hemic and lymphatic diseases, Virology, Marek Disease, medicine, Animals, Herpesvirus 2, Gallid, Oncogenesis, Poultry Diseases, BAC, mdv1-miR-M4, Marek's disease, Bacterial artificial chromosome, biology, MicroRNA, biology.organism_classification, MicroRNAs, RNA, Viral, Carcinogenesis, Chickens
Abstract

The microRNA (miRNA) mdv1-miR-M4, a functional miR-155 ortholog encoded by oncogenic Marek's disease virus (MDV), has previously been suggested to be involved in MDV pathogenesis. Using the technique of bacterial artificial chromosome mutagenesis, we have presently evaluated the potential role of mdv1-miR-M4 in the oncogenesis of the very virulent (vv) MDV strain GX0101. Unexpectedly, deletions of the Meq-cluster or mdv1-miR-M4 alone from the viral genome strongly decreased rather than abolished its oncogenicity. Compared to GX0101, mortalities of mutants GXΔmiR-M4 and GXΔMeq-miRs were reduced from 100% to 18% and 4%, coupled with the gross tumor incidence reduction from 28% to 22% and 8%, respectively. Our data suggests that the mdv1-miR-M4 is possibly an important regulator in the development of Marek's disease (MD) lymphomas but is not essential for the oncogenicity of vvMDV. In addition, some of the other Meq-clustered miRNAs may also play potentially critical roles in vvMDV induction of lymphomas.

Published
2014
Full Text
View/download PDF

74. Expression profiles of microRNAs encoded by the oncogenic Marek's disease virus reveal two distinct expression patterns in vivo during different phases of disease

Author

Man Teng, Aijun Sun, Cui Zhizhong, Liang-Hu Qu, Gaiping Zhang, Jun Luo, and Hui Zhou

Subjects
Gene Expression Regulation, Viral, Time Factors, animal structures, animal diseases, viruses, Biology, medicine.disease_cause, immune system diseases, hemic and lymphatic diseases, Virology, microRNA, Marek Disease, medicine, Animals, Gammaherpesvirinae, Neoplastic transformation, Lymphocytes, Viremia, Genetics, Regulation of gene expression, Marek's disease, Gene Expression Profiling, biology.organism_classification, Gene expression profiling, Mardivirus, MicroRNAs, Lytic cycle, Carcinogenesis, Chickens
Abstract

Marek's disease virus (MDV) is a long-recognized oncogenic herpesvirus, which induces lymphoma in its natural host that can be prevented by vaccination. MDV infection provides an excellent biological model for investigating the biology, genetics and immunology of viral oncogenesis. Recently discovered microRNAs (miRNAs) in the MDV genome have been suggested to have regulatory roles during MDV oncogenesis. We have examined the expression profiles of all 22 previously reported miRNAs encoded by MDV-1 in chickens artificially challenged with MDV-GX0101. We found that a subset of the miRNAs was differentially expressed during different phases of the developing disease. These miRNAs show early or late expression during disease progression, accompanied by obvious tissue-specific and differential expression patterns. This temporal and differential tissue distribution suggest that these miRNAs may perform different regulatory roles in switching from latency to lytic replication, immunosuppression, neoplastic transformation or other aspects of lymphoma formation. These reported in vivo expression profiles indicate the potentially functional MDV-1-encoded miRNAs that should be selected for further investigation of their functions in MDV oncogenesis.

Published
2010

75. Functional evaluation of the role of reticuloendotheliosis virus long terminal repeat (LTR) integrated into the genome of a field strain of Marek's disease virus

Author

Xiaoyun Xu, Lawrence Petherbridge, Yuguang Zhao, Cui Zhizhong, Aijun Sun, and Venugopal Nair

Subjects
LTR, viruses, Molecular Sequence Data, Mutagenesis (molecular biology technique), Pathogenesis, Genome, Virus, Birds, MDV, Virology, Marek Disease, Animals, Sequence Deletion, Immunosuppression Therapy, Recombination, Genetic, Genetics, Marek's disease, Reticuloendotheliosis virus, biology, Strain (chemistry), Terminal Repeat Sequences, Sequence Analysis, DNA, biology.organism_classification, Long terminal repeat, Mardivirus, Mutagenesis, Insertional, DNA, Viral, REV, Horizontal transmission
Abstract

MDV-GX0101 is a field strain of Marek's disease virus with a naturally occurring insertion of the reticuloendotheliosis virus (REV) LTR fragment. In order to study the biological properties of REV-LTR insertion in the MDV genome, we constructed a full-length infectious BAC clone of MDV-GX0101 strain and deleted the LTR sequences by BAC mutagenesis. The pathogenic properties of the LTR-deleted virus were evaluated in infected SPF birds. The study demonstrated that the LTR-deleted virus had a stronger inhibitory effect on the growth rates of the infected birds and induced stronger immunosuppressive effects. Surprisingly, however, the ability for horizontal transmission of the LTR-deleted virus appeared to be significantly weaker than its parental LTR-intact virus. Even though the precise molecular mechanisms are still not clear, the results of our studies demonstrate that the retention of the REV-LTR in the MDV genome decreases its pathogenic effects but increases its potential for horizontal transmission.

Published
2010
Full Text
View/download PDF

76. A BAC clone of MDV strain GX0101 with REV-LTR integration retained its pathogenicity

Author

Yuguang Zhao, YanPeng Li, Aijun Sun, Petherbridge Lawrence, Cui Zhizhong, and Venugopal Nair

Subjects
Bacterial artificial chromosome, animal structures, Multidisciplinary, viruses, food and beverages, Biology, medicine.disease_cause, Recombinant virus, Genome, Virology, Molecular biology, Virus, law.invention, chemistry.chemical_compound, chemistry, law, medicine, Recombinant DNA, Homologous recombination, Escherichia coli, DNA
Abstract

The complete genome of Marek’s disease virus (MDV) strain GX0101, which was integrated with the LTR sequences of REV, was cloned in Escherichia coli as a bacterial artificial chromosome (BAC). BAC vector sequences were introduced into the US2 locus of the MDV genome by homologous recombination. The viral DNA containing the BAC vector was used to transform Escherichia coli strain of DH10B. Then the recombinant virus was successfully rescued by transfection of the recombinant BAC DNA into primary chicken embryo fibroblast (CEF). This BAC viral clone was named bac-GX0101. When the reconstituted virus was inoculated into 1-day-old birds, visceral tumors could be detected as early as 62 d post infection. There was no difference in growth ability and pathogenicity to birds between the BAC derived virus and its parental virus. The BAC derived virus maintained its oncogenicity and immunosuppressive effects. In conclusion, the complete genome of GX0101 strain was successfully cloned into BAC and the infectious clone was rescued. With the powerful BAC manipulation system, the infectious clone will provide a useful tool for further understanding the functional roles of the inserted REV-LTR sequence in the GX0101 strain of MDV.

Published
2009

79. Dynamic Co-evolution and Interaction of Avian Leukosis Virus Genetic Variants and Host Immune Responses

Author

Dong, Xuan, primary, Meng, Fanfeng, additional, Hu, Tao, additional, Ju, Sidi, additional, Li, Yang, additional, Sun, Peng, additional, Wang, Yixin, additional, Chen, Wenqing, additional, Zhang, Fushou, additional, Su, Hongqin, additional, Li, Sifei, additional, Cui, He, additional, Chen, Junxia, additional, Xu, Shuzhen, additional, Fang, Lichun, additional, Luan, Huaibiao, additional, Zhang, Zhenjie, additional, Chang, Shuang, additional, Li, Jianliang, additional, Wang, Lei, additional, Zhao, Peng, additional, Shi, Weifeng, additional, and Cui, Zhizhong, additional

Published
2017
Full Text
View/download PDF

86. Epidemiological investigation of the novel genotype avian hepatitis E virus and co‐infected immunosuppressive viruses in farms with hepatic rupture haemorrhage syndrome, recently emerged in China.

Author

Su, Qi, Zhang, Yawen, Li, Yang, Cui, Zhizhong, Chang, Shuang, and Zhao, Peng

Subjects
RETROVIRUSES, ADENOVIRUS diseases, HEPATITIS E virus
Abstract

Since 2016, hepatic rupture haemorrhage syndrome (HRHS) appeared in chickens of China and caused huge economic loss. To assess the infection status of the avian hepatitis E virus (HEV) and co‐infected viruses, including avian leukosis virus (ALV), reticuloendotheliosis virus (REV), fowl adenovirus (FAdV), and chicken infectious anaemia virus (CIAV), in farms with HRHS, 180 liver samples were collected from 24 farms in different provinces and detected by strict molecular virology methods. Results showed that the positive rates of HEV, ALV, REV, FAdV, and CIAV were 74.44%, 20.00%, 27.78%, 31.11%, and 12.22%, respectively, whereas there are also 112 samples with co‐infection, for a rate of 58%. Meanwhile, the positive rate of HEV decreased gradually with age; the lowest positive rate of ALV (5.76%) and REV (19.23%) appeared in 25–35 weeks age, during which the positive rate of CIAV was the highest (19.23%); the positive rate of HEV in layers (64.00%) was lower than that of broilers (83.33%), but the positive rates of ALV (38.46%) and CIAV (15.38%) in layers were higher than that of broilers (5.88%, 9.80%); the positive rates of HEV (75.88%) and CIAV (15.60%) in parental generation (PG) were higher than that of commodity generation (CG, 64.10%, 0.00%), whereas the positive rate of ALV showed inverse relationship (PG: 14.89%; CG: 38.46%). Additionally, phylogenetic analysis showed that all the avian HEV identified this study belong to a novel genotype, and found the close relationship between the wild strains (REV and CIAV) and corresponding isolates from contaminated vaccine. The data presented in this report will enhance the current understanding of the epidemiology characteristics in farms with HRHS in China. [ABSTRACT FROM AUTHOR]

Published
2019
Full Text
View/download PDF

100. Avian leukosis virus in indigenous chicken breeds, China

Author

Dong, Xuan, primary, Zhao, Peng, additional, Xu, Bu, additional, Fan, Jianhua, additional, Meng, Fanfeng, additional, Sun, Peng, additional, Ju, Sidi, additional, Li, Yang, additional, Chang, Shuang, additional, Shi, Weifeng, additional, and Cui, Zhizhong, additional

Published
2015
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results