Vaccination inhibits the human adenoviral transduction in a mouse keratoconjunctivitis model

Adenovirus infections are a major cause of epidemic keratoconjunctivitis (EKC), which can lead to corneal subepithelial infiltrates and multifocal corneal opacity. In the current study, we investigated the use of an E1/E3-deleted adenovirus serotype 5 (Ad5) vector as a vaccine administered intramuscularly (IM) or intranasally (IN) against subsequent challenges with a luciferase-expressing Ad5 (Ad5-Luci) vector via eyedrop. We evaluated the adaptive immune response to Ad5 vector vaccination and confirmed a robust polyfunctional CD8 T cell response in splenic cells. Neutralizing Ad5 antibodies were also measured in the sera of vaccinated mice as well as Ad5 antibody in the eye wash solutions. Upon challenge with Ad5-Luci vector 8 weeks post the primary immunization, transduction was significantly reduced by > 70% in the vaccinated mice, which was slightly better in IM- vs. that in IN-vaccinated animals. Resistance to subsequent challenge was observed 10 months post primary IM vaccination, with sustained reduction up to 60% in the Ad5-Luci vector transduction. Passive immunization of naive mice with antisera from IM to vaccinated mice subsequently challenged with the Ad5-Luci vector resulted in approximately 40% loss in transduction efficiency. Furthermore, the mice that received IM immunization with or without CD8 T cell depletion showed > 40% and 70% reductions, respectively, in Ad8 genomic copies after Ad8 topical challenge. We conclude that Ad-vector vaccination successfully induced an adaptive immune response that prevented subsequent Ad transduction in the cornea and conjunctiva-associated tissues in a mouse model of adenovirus keratoconjunctivitis, and that both cellular and humoral immunity play an important role in preventing Ad transduction.     

膜表达热休克蛋白70真核表达载体的构建及其对肿瘤细胞的转染

目的构建普遍适合性的膜表达热休克蛋白70(HSP70)的真核表达载体,修饰并建立HSP 70表达并结合在细胞膜表面的肿瘤细胞.方法RT-PCR法从人胚肾中获取HSP 70的cDNA,扩增成带酶切位点的目的基因.选择载体pDisplay,将目的基因插入载体多克隆酶位点中.DNA测序证实后,以脂质体转染的方法,将载体转染到黑色素瘤细胞.用G418抗性筛选获得阳性克隆.结果酶切电泳和DNA测序证实载体构建正确;目的基因的上游带信号肽序列,下游带跨膜序列.RT-PCR产物电泳、Westem Blotting、激光共聚焦显微镜和流式细胞术证实大量HSP 70表达并结合在转染的黑色素瘤细胞膜表面.结论成功地构建了膜表达HSP 70的真核表达载体;转染到黑色素瘤细胞后,细胞膜表面表达丰富的HSP70.转染细胞可以进一步制备新型瘤苗.     

人血管内皮生长因子C基因真核表达载体的构建

目的：构建人血管内皮生长因子C(vascular endothelial growth factor C，VEGF-C)基因的真核表达载体，以便进一步研究VEGF-C基因在淋巴管生成中的作用。方法：根据人VEGF-C的cDNA序列，设计合成一对5′端分别含有EcoR I和BamH I酶切位点的特异性引物，运用RT-PCR方法克隆人乳腺癌细胞MDA-MB-231中的VEGF-C cDNA(1．26Kb；回收PCR产物(1．28Kb），并将其连接至克隆载体pMDl8-T中；重组的pMDl8-T在大肠杆菌DH5α内扩增后，经质粒提取、EcoR I和BamH I酶切，筛选出阳性重组子，并进行基因测序鉴定；琼脂糖凝胶电泳回收含有VEGF-C cDNA全长的酶切片断(1．27Kb)，然后在DNA连接酶作用下将其与真核表达载体pcDNA3．1(-)连接，重组质粒经EcoR I和BamH I酶切予以鉴定。结果：RT-PCR产物合有VEGF-C cDNA，基因测序显示重组的pMDl8-T中含有正确的人VEGF-C cDNA全长序列，重组的pcDNA3．1（-)中含有人VEGF-C cDNA全长序列。结论：成功构建了人类VEGF-C真核表达载体VEGF-C／pcDNA3．1（-)。     

心导纳微分环,肺导纳微分环最大向量正常值及其临床意义

本文报道３－５０岁２１４例心导纳微分环（ＣＡＤＬ）和肺导纳微分环（ＰＡＤＬ）最大向量振幅及方位正常值，结果随增龄变化振幅递减，方位递增，多数男＞女，部分组间有差异。４８例左向右分流先心病环体最大向量与肺动脉压之间呈平行关系，并探讨其临床意义。     

人TCA-12-2/TCB-7.1真核双表达载体的构建与表达

目的：将T细胞抗原受体基因TCA-12-2和TCB-7.1共同构建在真核表达载体pDC315，用于哺乳动物细胞293转染研究。方法： 将分离得到的淋巴细胞总RNA反转录合成cDNA,以此为模板进行PCR扩增得到TCA-12-2基因；以实验室保存含TCB-7.1基因的质粒为模板，扩增得到TCB-7.1基因。随后酶切，连入载体pIRES2-AcGFP1，通过亚克隆连入载体pDC315，得到重组质粒pDC315-TCA-12-2-TCB-7.1。重组体质粒经酶切鉴定后，并对插入的TCA-12-2和TCB-7.1基因片段进行测序，将鉴定好的阳性重组质粒用脂质体介导转染293细胞，并通过RT-PCR和流式细胞仪检测TCA-12-2和TCB-7.1基因的表达情况。结果： TCA-12-2和TCB-7.1可以同时构建在载体pDC315上，RT-PCR和流式细胞仪检测发现TCA-12-2和TCB-7.1基因可以成功在293细胞上表达。结论：成功构建了含TCA-12-2和TCB-7.1基因的双表达载体。     

Virion stability and aphid vector transmissibility of Cucumber mosaic virus mutants

The physical stability of virions of Cucumber mosaic virus (CMV) mutants was investigated to determine if relative stability correlated with efficiency of aphid transmission. Virion stability was evaluated by a urea disruption assay and by testing the infectivity of virus following purifications. All viruses were infectious when purified using a low salt buffer without organic solvent, whereas two of seven viruses were less stable and inactivated following purification with a high salt buffer and chloroform. These two viruses were both reassortants derived from the spontaneous transmission-defective mutant CMV-M (F1F2M3 and F1F2M3-L129P). F1F2M3 was relatively unstable, being disrupted between 0 and 1 M urea versus the wild-type CMV-Fny (F1F2M3) that was destabilized at 3-4 M urea. Modifications of F1F2M3 at three amino acid positions (129, 162, 168), singly or in combination, increased the relative stability of virions. A second class of transmission-defective CMVs with engineered mutations in the betaH-betaI surface loop of the CMV-Fny capsid protein (CP) exhibited near wild-type levels of stability. Lastly, a single Pro to Leu substitution at CP position 129 of CMV-Fny (F1F2M3-P129L) conferred the induction of necrosis in tobacco plants and reduced aphid transmissibility, but did not markedly alter the physical stability of virions. Thus, only among CMV-M derivatives harboring the CP mutation of Thr to Ala at position 162 were increases in stability correlated with restoration of transmissibility by the aphid Aphis gossypii.     

HOXB7 siRNA表达载体在裸鼠体内对人恶性黑色素瘤细胞株的影响

目的 探讨转染同源盒第7基因(HOXB7)siRNA质粒表达载体对人恶性黑色素瘤细胞株A375在裸鼠体内生长的影响.方法 裸鼠皮下接种人恶性黑色素瘤A375细胞,对2周后形成的瘤块进行分组干预.随机分为生理盐水对照组、阴性质粒组、HOXB7质粒组,观察转染后各组裸鼠移植瘤的生长情况;免疫组化法比较瘤体内微血管密度(MVD).结果 HOXB7质粒组的裸鼠移植瘤块生长慢、体积明显小于生理盐水对照组[(0.134±0.039)cm3比(1.006±0.235)cm3,P＜0.05],而阴性质粒组瘤块体积大小与生理盐水对照组无统计学差异[(0.929±0.157)cm3比(1.006±0.235)cm3,P＞0.05].HOXB7质粒组裸鼠体内肿瘤MVD低于生理盐水对照组[(2.8±1.9)比(19.9±5.6),P＜0.05],阴性质粒组与生理盐水对照组无统计学差异[(18.1±5.5)比(19.9±5.6),P＞0.05].结论 针对HOXB7 siRNA质粒表达载体可有效抑制A375细胞裸鼠体内肿瘤生长和瘤内血管生成.     

Simulation Studies of Latency Measures of Components of the Event-Related Brain Potential

We compared the accuracy of P300 latency estimates obtained with different procedures under several simulated signal and noise conditions. Both preparatory and signal detection techniques were used. Preparatory techniques included frequency filters and spatial filters (single electrode selection and Vector filter). Signal detection techniques included peak-picking, cross-correlation, and Woody filter. Accuracy in the latency estimation increased exponentially as a function of the signal-to-noise ratio. Both Woody filter and cross-correlation provided better estimates than peak-picking, although this advantage was reduced by frequency filtering. For all signal detection techniques, Vector filter provided better estimates than single electrode selection. Large component overlap impaired the accuracy of the estimates obtained with both single electrode selection and Vector filter, but with Vector filter impairment occurred only when the overlapping component had a scalp distribution that was similar to the scalp distribution of the signal component. The effects of varying noise characteristics, P300 duration and latency, and the parameters of Vector filter were also investigated.     

质粒型单纯疱疹病毒载体的构建及其在真核细胞中的表达

利用基因工程技术构建成功质粒型Ⅰ型单纯疱疹病毒（ＨＳＶ－１）载体ｐＨＳＶ，其中含有ＨＳＶ－１包装信号序列和ＨＳＶ－１复制起点，以及ＨＳＶ－１ＩＥ６８启动子。为验证其构建是否成功，在其ＩＥ６８启动子下游的多克隆位点上插入了Ｅ．ｃｏｌｉＬａｃＺ基因，构建成ｐＨＳＶＬ质粒。用ＨＳＶ－１温度敏感株（ｔｓＫ株）超感染传代细胞后，将这种质粒转染入该细胞，ｐＨＳＶＬ可在辅助病毒ＨＳＶ－１ｔｓＫ（允许温度为３１℃）存在的条件下被包装成病毒颗粒，由此得到的混合病毒含有ＨＳＶ－１ｔｓＫ和ｐＨＳＶＬ假病毒颗粒，收获后再感染培养的Ｖｅｒｏ细胞，原位检测β－半乳糖苷酶活性呈阳性。同时用ｐＨＳＶＬ病毒接种体外培养的ＳＤ大鼠胚胎脊髓运动神经元，用Ｘ－ｇａｌ原位检测β－半乳糖苷酶的活性，亦发现有阳性的神经元存在。说明载体ｐＨＳＶＬ携带的报告基因ｌａｃＺ在这两种真核细胞中均得以正确表达。报告基因可为其它目的基因所代替，可用于神经生理、病理以及神经系统疾病基因治疗的实验研究。     

趋化因子受体CCR5反义RNA在真核细胞中的表达

目的 构建趋化因子受体CCR5反义RNA真核表达载体并获取重组假病毒颗粒以用于抗HIV-1研究，方法 用RT-PCR法从健康人外周血单个核细胞（PBMCs)中获得趋化因子受体CCR5翻译起始区的基因片段，并以正、反两个方面定向插入到真核表达载体pLXSN上，重组载体用脂质体转染剂（lipofectAMINE)转染PA317包装细胞，抗-G418克隆的细胞上清经逆转录后用荧光定量PCR（FQ-PCR）测定假病毒滴度，进一步感染NIH/3T3细胞。结果 CCR5正、反义RNA的真核表达载体。经PA317细胞包装形成的假病毒颗粒已成功地感染NIH/3T3细胞，目的基因在该细胞中得到整合与表达。结论 从PBMCs中获得的趋化因子受体CCR5基因片段通过逆转录病毒载体可转移至真核细胞中并得到表达，为进一步研究CCR5反义RNA的抗HIV-1作用奠定了基础。