作者机构：
[Yang, Yi] Hunan Agr Univ, LFP, Coll Vet Med, Changsha 410128, Hunan, Peoples R China.;Hunan Agr Univ, RCRV, Coll Vet Med, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Yang, Yi] H;Hunan Agr Univ, LFP, Coll Vet Med, Changsha 410128, Hunan, Peoples R China.
关键词：
Chimeric virus-like particles;Immune responses;Porcine circovirus type 2;Porcine reproductive and respiratory syndrome virus GP5 epitope B
摘要：
Virus-like particles (VLPs) can be used as transfer vehicles carrying foreign proteins or antigen epitopes to produce chimeric VLPs for bivalent or multivalent vaccines. Based on the crystal structure of porcine circovirus type 2 (PCV2) capsid protein (Cap), in addition to alignment of the Cap sequences collected from various isolates of PCV2 and PCV1, we predicted that Loop CD of the PCV2 Cap should tolerate insertion of foreign epitopes, and furthermore that such an insertion could be presented on the surface of PCV2 VLPs. To validate this, the GP5 epitope B of porcine reproductive and respiratory syndrome virus (PRRSV) was inserted into Loop CD of the PCV2 Cap. The 3D structure of the recombinant PCV2 Cap (rCap) was simulated by homology modeling; it appeared that the GP5 epitope B was folded as a relatively independent unit, separated from the PCV2 Cap backbone. Furthermore, based on transmission electron microscopy, the purified PCV2 rCap self-assembled into chimeric VLPs which entered PK-15 cells. In addition, PCV2 chimeric VLPs induced strong humoral (neutralizing antibodies against PCV2 and PRRSV) and cellular immune responses in mice. We concluded that the identified insertion site in the PCV2 Cap had great potential to develop PCV2 VLPs-based bivalent or multivalent vaccines; furthermore, it would also facilitate development of a nano-device to present a functional peptide on the surface of the VLPs that could be used for therapeutic purposes.
作者：
Dong, Wang Nai;Jun, Li Jing;Bing, Wang Ai;Zhe, Zhu;Yan, Chang;...
期刊：
POLISH JOURNAL OF VETERINARY SCIENCES,2016年19(3):471-476 ISSN：1505-1773
通讯作者：
Bang, Deng Zhi
作者机构：
[Bing, Wang Ai; Dong, Wang Nai; Yu, Mao; Feng, Wang Zan; Jun, Li Jing; Zhe, Zhu; Yang, Zan; Yan, Chang; Bang, Deng Zhi] Hunan Agr Univ, Coll Vet Med, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Bang, Deng Zhi] H;Hunan Agr Univ, Coll Vet Med, Changsha 410128, Hunan, Peoples R China.
关键词：
Life Sciences;Zoology;Life Sciences, other;Medicine;Veterinary Medicine
摘要：
In order to investigate whether PCV2b can be transmitted across the placenta in sows thereby causing vertical infection of fetuses, six sows in 75 day of pregnancy were either intramuscularly inoculated with a PCV2b culture supernatant (n = 4) or mock infected with cell culture supernatant (n = 2). At parturition, 3 newborn piglets from each litter were randomly selected and euthanatized prior to suckling. Samples of the mesenteric lymph nodes, spleens, kidneys, hearts and lungs were collected for PCR, histopathological and immunohistochemical assays. The results showed that the newborn piglets from PCV2b-infected sows had histopathological lesions in the tested tissues. Moreover, PCV2b antigen and DNA were detected as well. These findings therefore suggested that porcine circovirus type 2b can be transmitted across the placenta of sows, thereby leading to PCV2b vertical infection of the fetuses.
作者机构：
[Naidong Wang; Yang Zhan; Aibing Wang; Zhe Zhu; Zhanfeng Wang] College of Veterinary Medicine, Hunan Agricultural University, Changsha, China;[Zhibang Deng; Yi Yang] College of Veterinary Medicine, Hunan Agricultural University, Changsha, China zbangd@hunau.edu.cn yiyang@hunau.edu.cn
通讯机构：
[Deng, Zhibang] C;College of Veterinary Medicine, Hunan Agricultural University, Changsha, China yiyang@hunau.edu.cn
摘要：
为了解湖南省猪源粪肠球菌临床分离株的耐药性及各耐药基因的分布情况,使用K-B法检测了42株猪源粪肠球菌对11种抗生素的敏感性,采用PCR方法检测了粪肠球菌中8种耐药基因的分布情况。结果显示,湖南省临床分离的42株粪肠球菌对大部分的抗生素高度耐药,对四环素、氯霉素、苯唑青霉素、红霉素、米诺霉素、左氧氟沙星、高浓度庆大霉、高浓度链霉素、环丙沙星、万古霉素、青霉素G的耐药率依次为100%、92.9%、88.1%、83.3%、81%、57.1%、52.4%、47.6%、45.2%、31%、11.9%;耐药基因的检出率为Aac（6）’/aph（2’’）97.6%、ant（6）’-Ⅰ90%、aph（3）’-Ⅲ76.2%、tet M 90.5%、erm B 73.8%、Van A 4.8%、Van B 54.8%、Van C 88.1%。从表型与基因型共同分析粪肠球菌的耐药性,发现粪肠球菌的多耐药性严重,其耐药表型与耐药基因并不完全一致。
摘要：
High-titer serologically detected male (SDM) antibody fragments are essential for specific binding to the SDM antigen and promoting its application. The A8 clone previously obtained from an original phage antibody library was further affinity-matured by light- and high-chain shuffling respectively, to generate the end product B9 clone. The binding capacity of B9 phage Fabs to male splenocytes doubled the value of its parental A8 clone (determined using ELISA). Based on immunofluorescent staining, B9-Fabs mainly bound to the surface antigen of male splenocytes and recognized testicular cells. The resulting B9-Fabs detected a single protein (approximately 40 kDa determined using Western blot analysis of male splenocytes and testis); its high SDM antigen binding ability might have been because of mutation sites and varied lengths of the amino acid sequences in the complementarity determining regions-3 of the kappa and Fd chains. The new recombinant clones of Fab that were phage-enhanced using chain shuffling were candidate molecules for investigating molecular mechanisms of SDM antigens specific binding and applications. (C) 2013 Elsevier Inc. All rights reserved.
