稳定表达人乳头瘤病毒(HPV)58型E6E7融合基因的B16细胞系的建立

目的:构建pIRES-neo-HPV58E6E7真核表达载体,稳定转染入小鼠黑色素瘤B16细胞,建立稳定表达HPV58E6E7基因的B16细胞系。方法:采用PCR方法扩增出HPV58E6E7融合基因的全长序列,利用DNA重组技术将其定向插入到真核表达载体pIRES-neo中,并加入酶切位点和6×his标签,构建重组真核表达质粒pIRES-neo-HPV58E6E7。利用阳离子脂质体介导法将其转染入小鼠黑色素瘤B16细胞,经G418加压筛选出稳定转染的阳性克隆。利用Western blot、流式细胞术、免疫荧光等检测方法验证HPV58E6E7融合基因在稳定转染的B16细胞株中的表达。结果:经PCR、限制性内切酶鉴定及测序分析,pIRES-neo-HPV58E6E7重组质粒构建正确,转染B16细胞株后,经过Western blot、流式细胞术和免疫荧光等检测显示B16细胞株能够稳定、高效表达HPV58E6E7融合基因,表明B16-HPV58E6E7稳定转染细胞系构建成功。结论:成功构建了pIRES-neo-HPV58E6E7真核表达载体,建立了可以高效、稳定表达HPV58E6E7融合基因的B16细胞系。该稳定转染细胞系的建立为进一步研究HPV58治疗性基因疫苗的功能提供了良好的靶细胞,为其在肿瘤免疫治疗中的应用奠定了研究基础。     

HPV16E7E6重组腺病毒的构建及免疫效果评价

目的 构建用于宫颈癌治疗的HPV16E7E6重组腺病毒并评价其免疫效果.方法 根据哺乳细胞使用密码子的偏嗜性设计HPV16E7E6融合蛋白表达优势密码子基因序列并合成.将合成的E7E6基因插入腺病毒重组穿棱质粒pCD316后,与Ad5腺病毒骨架质粒共转染293细胞,重组病毒经单斑纯化并进行目的基因插入及表达的鉴定.扩增纯化重组病毒后免疫小鼠,评价其免疫活性.结果 PCR试验证明E7E6密码子优化基因成功插入Ad5病毒;Western blot检测结果表明重组腺病毒中E7E6优化基因能高效表达,该重组腺病毒免疫C57小鼠后,可诱发强特异性T细胞免疫应答,在小鼠体内能完全抑制5×104 TC-1移植瘤细胞的生长.结论 重组HPV16E7E6腺病毒可作为治疗HPV慢性感染或宫颈癌的候选疫苗.     

人乳头瘤病毒16 E5(HPV16 E5)蛋白抑制角质形成细胞生长因子诱导的细胞自噬

目的研究人乳头瘤病毒16 E5(HPV16 E5)蛋白对角质形成细胞生长因子(KGF)诱导的细胞自噬的影响。方法构建HPV16 E5蛋白真核表达载体p CI-neo-E5,采用LipofectamineTM2000转染至Ha Ca T人角质形成细胞,实时定量PCR检测HPV16 E5 mRNA转录水平。转染p CI-neo-E5并以KGF刺激Ha Ca T细胞后,实时定量PCR检测自噬相关蛋白beclin 1、自噬相关基因5(ATG5)、ATG7及LC3B mRNA的水平,Western blot法检测LC3BⅡ蛋白的表达量,免疫荧光技术检测LC3B的分布。结果成功构建HPV16 E5真核表达载体p CI-neo-E5并可有效表达。角质形成细胞转染p CI-neo-E5,自噬相关蛋白mRNA的水平显著降低,抑制KGF诱导的LC3BⅡ表达水平升高和LC3B的聚集。结论 HPV16 E5蛋白通过下调自噬相关蛋白的表达,抑制KGF诱导的细胞自噬。     

逆转录病毒载体介导HPV16 E6E7基因转化人胚食管纤维细胞的研究

目的 研究HPV16型病毒感染与食管癌发生的关系。方法 包装含有HPVl6E6E7基因重组逆转录病毒，以重组病毒感染人胚食管纤维细胞，在TPA协同下诱导SCID小鼠成瘤。结果 重组病毒感染人胚食管纤维细胞可以诱导SCID小鼠形成肉瘤，可以检测到E6E7基因的存在及表达，流式细胞仪检测从瘤组织培养出来的纤维细胞，确定为异倍体；但未能诱导人胚食管组织成瘤。结论 建立的重组逆转录病毒系统可以成功介导HPV16E6E7基因的转移，可以应用于HPV致瘤性研究。     

稳定表达人乳头瘤病毒58型(HPV58)E6E7融合基因的人宫颈癌细胞株C33A的构建及验证

为构建稳定表达人乳头瘤病毒(HPV)58型E6E7融合基因的人宫颈癌C33A细胞系,将实验前期构建好并实现真核表达的重组慢病毒颗粒LV-HPV58E6E7转染入HPV(–)的人宫颈癌C33A细胞,经流式细胞仪分选出稳定转染的阳性克隆,利用四唑盐比色(MTT)法检测转染后细胞的生长情况以及流式细胞术检测细胞周期,并将稳定表达HPV58E6E7融合基因的C33A细胞LV-HPV58E6E7/C33A接种于裸鼠左腋下成瘤,用荧光定量PCR(q RT-PCR)、Western blot检测瘤组织中HPV58型E6E7融合基因的转录和表达。结果显示HPV58E6E7融合基因可促进C33A细胞的增殖;LV-HPV58E6E7/C33A细胞株能在裸鼠体内稳定转录及表达HPV58型E6E7融合基因。这表明我们成功建立了能稳定表达HPV58E6E7融合基因的人宫颈癌C33A细胞系LV-HPV58E6E7/C33A,为HPV58型治疗性疫苗的免疫效果检测提供了抗原细胞来源。     

HPV 16 E6E7基因修饰树突状细胞疫苗诱导CTL致CaSki细胞凋亡体外实验研究

目的:采用人乳头状瘤-16(HPV-16)E6E7重组腺病毒(pAd-E6E7)转染树突状细胞(Dendritic cell,DC),观察基因修饰的DC疫苗诱导细胞毒性T淋巴细胞(Cytotoxic Tlymphocyte,CTL)致使CaSki细胞凋亡的效果。方法:将pAd-E6E7转染体外培养的小鼠未成熟树突状细胞制备DC疫苗,激光共聚焦显微镜观察转染的小鼠未成熟树突状细胞绿色荧光蛋白表达,流式细胞术检测转染前后小鼠树突状细胞表面标志物(CD40、CD86、MHCⅡ和CD11C)。DC疫苗诱导产生特异性细胞毒性T淋巴细胞,与CaSki细胞共培养后,采用DAPI、TUNEL及流式细胞术检测CaSki细胞凋亡情况。结果:pAd-E6E7成功转染体外培养的小鼠未成熟树突状细胞,体外转染效率约为40%～50%,成功制备了HPV16 E6E7基因修饰树突状细胞疫苗,诱导产生细胞毒性T淋巴细胞,经DAPI、TUNEL及流式细胞术检测证明CaSki出现凋亡。结论:以带有HPV16 E6E7基因的重组腺病毒载体转染DC制备基因修饰的DC疫苗,诱导CTL致使CaSki细胞出现凋亡。     

修饰后中国山东地方株HPV16 E6E7基因的转化活性检测及免疫原性研究

目的 利用突变修饰后消除转化活性并保留抗原性的中国山东地方株人乳头瘤病毒16型（HPV16）E6E7基因，研制HPV16 DNA疫苗。方法 定点突变E6的终止密码，并保证E7读码框架不定；定点突变E7蛋白的Rb结合区中对其转化活性维持起关键作用的第24位氨基酸。突变修饰后的基因命名为fmE6E7。PCR扩增fmE6E7，重组人pLNCX载体，脂质体法转染3T3细胞，免疫荧光组织化学及Western blot检测转染细胞蛋白的表达。经软琼脂集落培养法和BALB／c裸鼠皮下接种法检测fmE6E7的转化活性。然后PCR扩增fmE6E7，构建pVR1012-fmE6E7真核表达质粒，于C57BL／6小鼠肌肉内直接进行裸DNA免疫，^51Cr释放法体外分析免疫鼠的细胞毒性T淋巴细胞活性，间接ELISA法检测免疫鼠血清中E7特异性抗体。结果 测序证实获得了预期的突变结果。pLNCX-fmE6E7转染细胞体外软琼脂培养3周未见集落形成；裸鼠皮下接种2月后未见移植瘤形成（0／3）。免疫鼠获得了较好的E7特异性的抗体E和抗原特异性的CTL。结论 修饰后E6E7基因可融合表达，转化活性消除的同时还可诱发特异的细胞免疫和体液免疫，表明中国山东地方株的E6E7基因可作为HPV16治疗性DNA疫苗的靶基因。     

人乳头瘤病毒16型E2蛋白表达、纯化及抗血清制备

目的 表达人乳头瘤病毒16型(HPV16) E2蛋白,并制备小鼠抗HPV16 E2血清.方法 采用PCR技术扩增HPV16E2基因,构建入pET21b载体,重组表达载体pET21 b-HPV16E2经鉴定后转化大肠埃希菌BL21(DE3),诱导表达并鉴定表达产物.经纯化、变性和复性方法,制备可溶性HPV16 E2蛋白.免疫BALB/c小鼠制备抗血清,检测小鼠IFN-γ、CD4+T细胞、CD8+T细胞、CD4/CD8比值和抗血清滴度变化.结果 酶切和测序结果表明pET21b-HPV16 E2构建成功.表达蛋白相对分子质量(Mr)为42 000,Western blot法证明具有较高特异性.小鼠抗血清效价升高,CD4+T细胞数量和CD4/CD8比值升高,小鼠IFN-γ无升高.结论 成功制备可溶性HPV16 E2蛋白和小鼠抗HPV16 E2高效价的抗血清.     

HPV16E7E6抗原表位嵌合体DNA抗肿瘤疫苗的研究

目的:探讨HPV16 E7、E6抗原表位与HSP70 N端重组DNA疫苗抗肿瘤活性.方法:以重叠PCR将HPV16 E7基因N端60个氨基酸的编码序列与E6基因的10个(48～57)氨基酸的编码序列及HSP70 N端序列进行融合.以pcDNA3.0为载体,构建真核表达载体pcD-E76HSP.重组质粒免疫C57BL/6小鼠后,通过淋巴细胞增殖实验和细胞毒性杀伤实验研究该疫苗激发的细胞免疫反应及反应强度;观察该疫苗对C57BL/6小鼠TC-1肿瘤细胞移植瘤的治疗效果.结果:重组DNA疫苗免疫C57BL/6小鼠后,小鼠脾淋巴细胞体外增殖明显,并可诱导产生针对TC-1肿瘤细胞的特异性CTL反应;体内抑瘤试验显示该疫苗对HPV16病毒转化的TC-1细胞小鼠移植瘤的生长有抑制作用.结论:该疫苗能激发特异性细胞免疫反应,显著抑制HPV16转化的TC-1肿瘤细胞生长.     

共表达HPV16型E6和E7突变基因重组痘苗病毒的构建及其抗肿瘤免疫效果的观察

目的：构建用于子宫颈癌治疗的HPV16型E6和E7重组痘苗病毒实验性疫苗株，并对其抗肿瘤免疫效果进行初步评价。方法：以痘苗病毒为载体、利用同源重组技术构建共表达HPV16 E6和E7基因的重组痘苗病毒。该病毒免疫C57BL／6小鼠后，检测其免疫原性和抗移植瘤生长情况。结果：PCR结果显示，重组病毒VmE6E7的TK基因内插入了分别由痘苗病毒早晚期启动子H6和7．5K表达的ME6和ME7－1基因。动物实验结果表明，rVmE6E7在C57BL／6小鼠体内可诱发E6和E7特异性抗体产生，被免疫小鼠能够抵抗HPV16 E6E7转化的同系肿瘤细胞的攻击。结论：获得1株用于宫颈癌治疗的HPV16型实验疫苗株，为进一步研制人用HPV16型疫苗株奠定了基础。     

E.E.G. preprocessing by an on-line amplitude-and-frequency analyser

A four-channel e.e.g. preprocessing device is described, based on the signal's wave durations and amplitude measurement and their classification into four frequency and three amplitude bands. The analysis results are ordinarily written back on the e.e.g. machine for visual interpretation, in an appropriate polarity-and-amplitude coded form, occupying two channels per each processed channel. Outputs are provided for oscilloscope monitoring, further computer processing, etc. The possibilities of this device are discussed and examples of humans' and cats' e.e.g. analysis are given. About 10 devices of this type have been built and used for the last two years in several laboratories dealing with e.e.g. monitoring methods for experimental purposes.     

The stability of the human papillomavirus E6 oncoprotein is E6AP dependent

Human papillomavirus (HPV) E6 oncoproteins target numerous cellular proteins for ubiquitin-mediated degradation. In the case of p53 this is mediated by the E6AP ubiquitin ligase. However, there are conflicting reports concerning how central E6AP is to the global function of the HPV-16 and HPV-18 E6 oncoproteins. To investigate this further we have analysed the effects of E6AP removal upon the stability of endogenously expressed E6 protein. We show that when E6AP is silenced in HPV-positive cells, E6 protein levels are dramatically decreased in a proteasome-dependent manner. Further, we show that when E6AP is depleted in HeLa cells, E6 has a greatly decreased half-life. In addition, overexpression of E6AP stabilises ectopically expressed HPV-16 and HPV-18 E6 in a manner that is independent of its ubiquitin ligase activity. These results demonstrate that the stability of HPV E6 is critically dependent upon the presence of E6AP.     

A novel interaction between the human papillomavirus type 16 E2 and E1^E4 proteins leads to stabilization of E2

The E4 (also called E1^E4) and E2 proteins of human papillomavirus type 16 are thought to be expressed within the same cells of a lesion, and their open reading frames overlap, suggesting that they may have a functional relationship. We have examined the effect of co-expression of these two proteins and found that each enhances the level of the other. We also identified the N-terminus of E2 as the first example of a viral protein that directly binds the HPV16 E1^E4 protein. This appears to result in the E2 becoming less soluble and promotes its relocation from the nucleus to the cytoplasm. In addition, the turnover of the E2 protein is decreased in the presence of E1^E4. All this raises the possibility that E1^E4 acts to influence E2 activity by varying the amount of available E2 in the cell.     

戊型肝炎病毒结构区基因在大肠杆菌中的表达

目的获得可用于研制戊型肝炎疫苗的基因工程抗原。方法用非融合蛋白表达载体ｐＥＴ１１ａ,表达戊型肝炎病毒（ＨＥＶ）第二读码框区（ＯＲＦ２）２２４６６０ａａ段蛋白。结果得到分子量为５００００的表达产物,经Ｗｅｓｔｅｒｎｂｌｏｔ证实,表达产物具有ＨＥＶ特异抗原性。结论该基因工程抗原可能具有制备戊型肝炎疫苗的前景。     

Apolipoprotein E5 and E7 in apparently healthy Japanese males: Frequencies and relation to plasma lipid levels

Summary In order to determine the frequencies of apolipoproteins (apo) E5 and E7 and their relation to plasma lipid levels, apo E phenotypes were determined in 608 healthy Japanese male adults by two-dimensional gel electrophoresis. Apo E5 and E7 were observed in 2.8% of the subjects, in addition to the three common apo E isoforms, E2, E3, and E4. Apo E5 was divided into two subtypes based on the migration rate on SDS/PAGE, E5f is the type with faster migration and E5s slower migration. The gene frequencies were: the 3 allele, 0.841; the 4 allele, 0.095; the 2 allele, 0.049; the 7 allele, 0.009; the 5 allele encoding apo E5f (the 5f allele), 0.004; and the 5 allele encoding apo E5s (the 5s allele), 0.001. The five individuals with apo E5f and the eleven with apo E7 were heterozygotes and normocholesterolemic. Also plasma apo B and apo E levels were not increased in any subjects with apo E5f or apo E7. The data suggests that apo E5f and E7 are not rare in the Japanese population but that neither apo E5f nor E7 are associated with hypercholesterolemia in most of the heterozygotes.     

Non-apolipoprotein E and apolipoprotein E genetics of sporadic Alzheimer's disease

The genetic epidemiology of sporadic Alzheimer's disease (SAD) remains a very active area of research, making it one of the most prolifically published areas in medicine and biology. Numerous putative candidate genes have been proposed. However, with the exception of apolipoprotein E (APOE), the only confirmed genetic risk factor for SAD, all the other data appear to be not consistent. Nevertheless, the genetic risk for SAD attributable to the APOE gene in the general population is 20–70%, providing a strong evidence for the existence of additional genetic risk factors. The first part of the present article was dedicated to non-APOE genetics of SAD, reviewing chromosomes-by-chromosomes the available data concerning the major candidate genes. The second part of this article focused on some recently discovered aspects of the APOE polymorphism and their implications for SAD. An attempt to identify the future directions for non-APOE genetic research in SAD was also discussed.     

人乳头瘤病毒16型修饰后E6E7基因免疫原性增强

利用突变修饰后消除转化活性并保留抗原性的中国山东地方株人乳头瘤病毒16型(human papillomavirus type 16,HPVl6)E6E7融合基因(fmE6E7)，研制治疗HPVl6相关疾病的DNA疫苗。用PCR扩增fmE6E7基因后，插人真核表达质粒获得pVRl012-fmE6E7，瞬时转染Cos-7细胞，免疫荧光法检测证实其表达后，在C57BL／6小鼠后腿肌肉进行裸DNA免疫，5lCr释放法体外分析免疫鼠的细胞毒性T淋巴细胞活性Cytotoxic T lymphocyte，CTL)，间接ELISA法检测免疫鼠血清中E7特异性抗体。研究表明修饰后的中国地方株E6E7融合基因可诱导机体产生特异的抗体反应和CTL反应，与单独野生型E7基因免疫相比，E6E7融和基因可更好的活化CTT反应。表明修饰后消除转化活性的中国地方株E6E7融合基因可作为HPVl6治疗性DNA疫苗的靶基因。     

The E6E7 oncoproteins of cutaneous human papillomavirus type 38 interfere with the interferon pathway

Non-melanoma skin cancer is the most frequent malignancy in Caucasian populations. Evidence suggests the involvement of cutaneous Human Papillomavirus (HPV) of the genus beta (beta) in this disease. The ability of E6 and E7 of mucosal HPV to promote cellular transformation and inhibit immune response-related pathways plays a key role in cervical carcinogenesis. beta HPV-38 E6 and E7 display transforming activities in in vitro and in vivo models, but their impact on immune surveillance is unknown. Here we show that HPV-38 E6 and E7 affect the IFN-induced up-regulation of MHC class I. Expression of the two viral proteins in HaCaT keratinocytes led to a decrease of MHC I levels. This down-regulation is associated with a reduction of expression of MHC I heavy chain, of the peptide chaperone TAP and of the STAT-1 downstream effector IRF-1. The down-regulation of these proteins is ultimately due to the inhibition of STAT-1 expression. Analysis of cells expressing either HPV-38 E6 or E7 suggests that these effects are primarily the result of E6 expression, although a contribution by E7 cannot be excluded. We conclude that HPV-38 encodes oncoproteins that potentially contribute to the evasion of host immune surveillance.