Low-dose radiation enhances therapeutic HPV DNA vaccination in tumor-bearing hosts

Current therapeutic approaches to treatment of patients with bulky cervical cancer are based on conventional in situ ablative modalities including cisplatin-based chemotherapy and radiation therapy. The 5-year survival of patients with nonresectable disease is dismal. Because over 99% of squamous cervical cancer is caused by persistent infection with an oncogenic strain of human papillomavirus (HPV), particularly type 16 and viral oncoproteins E6 and E7 are functionally required for disease initiation and persistence, HPV-targeted immune strategies present a compelling opportunity in which to demonstrate proof of principle. Sublethal doses of radiation and chemotherapeutic agents have been shown to have synergistic effect in combination with either vaccination against cancer-specific antigens, or with passive transfer of tumor-specific cytotoxic T lymphocytes (CTLs). Here, we explored the combination of low-dose radiation therapy with DNA vaccination with calreticulin (CRT) linked to the mutated form of HPV-16 E7 antigen (E7(detox)), CRT/E7(detox) in the treatment of E7-expressing TC-1 tumors. We observed that TC-1 tumor-bearing mice treated with radiotherapy combined with CRT/E7(detox) DNA vaccination generated significant therapeutic antitumor effects and the highest frequency of E7-specific CD8⁺ T cells in the tumors and spleens of treated mice. Furthermore, treatment with radiotherapy was shown to render the TC-1 tumor cells more susceptible to lysis by E7-specific CTLs. In addition, we observed that treatment with radiotherapy during the second DNA vaccination generated the highest frequency of E7-specific CD8⁺ T cells in the tumors and spleens of TC-1 tumor-bearing mice. Finally, TC-1 tumor-bearing mice treated with the chemotherapy in combination with radiation and CRT/E7(detox) DNA vaccination generate significantly enhanced therapeutic antitumor effects. The clinical implications of the study are discussed. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

重组人乳头瘤病毒核酸疫苗诱导特异性淋巴细胞增殖

采用分子克隆技术,将人乳头瘤病毒16型E7(HPV 16 E7)基因重组于真核表达载体上,构建了HPV 16 E7核酸疫苗.将该疫苗通过皮内注射方式免疫Balb/c纯系小鼠.基因免疫后制备小鼠脾淋巴细胞悬液,经体外E7蛋白再次刺激后用MTT比色法检测出了特异性淋巴细胞增殖反应.由于特异性淋巴细胞增殖是反映细胞免疫功能的简便有效方法,所以本实验表明HPV 16 E7核酸疫苗构建正确,并能够诱导机体产生特异性细胞免疫应答.     

宫颈癌患者HPV16/18型病毒感染及阴道菌群观察

目的 探讨宫颈癌与人乳头瘤病毒(HPV)感染高危型HPV(HPV16/18)表达及阴道菌群的关系。 方法 回顾性分析我院2018年1月-2020年1月收治的37例宫颈癌患者的临床资料,将其设为宫颈癌组。纳入同期于我院治疗的43例宫颈上皮内瘤变(CIN)患者的临床资料设为CIN组。比较两组基础资料(年龄、绝经情况、孕次、产次、HPV16/18阳性表达、阴道菌群、饮食卫生习惯和家族遗传史)差异,并对有差异信息进行赋值,以多因素Logistic回归模型分析宫颈癌发生的危险因素。 结果 经单因素分析,两组患者年龄、绝经情况、孕次和产次比较,差异无统计学意义(P>0.05);宫颈癌组HPV16/18阳性、阴道菌群失调、饮食卫生习惯较差以及存在家族遗传史患者数显著多于CIN组(P结论 宫颈癌发生危险因素较多,临床应针对存在危险因素的患者加强监测并给予相应干预从而降低宫颈癌发生风险。     

Mutation in the immunodominant epitope of the HPV16 E7 oncoprotein as a mechanism of tumor escape

Infection with high-risk types of human papillomavirus (HPV) can cause the development of malignant tumors. To study mechanisms responsible for immune escape of tumor cells infected with HPV16, we previously used mouse oncogenic TC-1 cells producing HPV16 E6 and E7 oncoproteins to derive TC-1 clones resistant to immunization against E7. We have found immunoresistance of the clones to correlate with the point mutation in the E7 oncogene, which resulted in the N53S substitution in the immunodominant epitope RAHYNIVTF (aa 49–57). Here, we have shown that this mutation reduced stabilization of H-2D^b molecules on RMA-S cells and eliminated immunogenicity of E7. The resistance of TC-1 clones was E7-specific as immunization against E6 inhibited tumor growth. Transduction of the TC-1/F9 clone carrying the mutated epitope with the wild-type E7 gene restored susceptibility to immunization against E7. Our results suggest that mutagenesis of tumor antigens can lead to the escape of malignant cells and should be considered in the development and evaluation of cancer immunotherapy.     

Enhancement of immunogenicity of HPV16 E7 oncogene by fusion with E. coli beta-glucuronidase

BACKGROUND: Human papillomavirus type 16 (HPV16) E7 is an unstable oncoprotein with low immunogenicity. In previous work, we prepared the E7GGG gene containing point mutations resulting in substitution of three amino acids in the pRb-binding site of the HPV16 E7 protein. METHODS AND RESULTS: To increase E7GGG immunogenicity we constructed fusion genes of E. coli beta-glucuronidase (GUS) with one or three copies of E7GGG. Furthermore, a similar construct was prepared with partial E7GGG (E7GGGp, 41 amino acids from the N-terminus). The expression of the fusion genes was examined in human 293T cells. Quantification of GUS activity and the amount of E7 antigen showed substantially reduced GUS activity of fusion proteins with complete E7GGG that was mainly caused by decrease of their steady-state level in comparison with GUS or E7GGGpGUS. Still, the steady-state level of E7GGG.GUS was about 20-fold higher than that of the E7GGG protein. The immunogenicity of the fusion genes with complete E7GGG was tested by DNA immunisation of C57BL/6 mice with a gene gun. TC-1 cells and their clone TC-1/A9 with down-regulated MHC class I expression were subcutaneously (s.c.) inoculated to induce tumour formation. All mice were protected against challenge with TC-1 cells and most animals remained tumour-free in therapeutic-immunisation experiments with these cells, in contrast to immunisation with unfused E7GGG and the fusion with the lysosome-associated membrane protein 1 (Sig/E7GGG/LAMP-1). Significant protection was also recorded against TC-1/A9 cells. Both tetramer staining and ELISPOT assay showed substantially higher activation of E7-specific CD8+ lymphocytes in comparison with E7GGG and Sig/E7GGG/LAMP-1. Deletion of 231 bp in the GUS gene eliminated enzymatic activity, but did not influence the immunogenicity of the E7GGG.GUS gene. CONCLUSIONS: The findings demonstrate the superior immunisation efficacy of the fusion genes of E7GGG with GUS when compared with E7GGG and Sig/E7GGG/LAMP-1. The E7GGG.GUS-based DNA vaccine might also be efficient against human tumour cells with reduced MHC class I expression.     

Enhanced potency of individual and bivalent DNA replicon vaccines or conventional DNA vaccines by formulation with aluminum phosphate

DNA vaccines against botulinum neurotoxin (BoNTs) induce protective humoral immune responses in mouse model, but when compared with conventional vaccines such as toxoid and protein vaccines, DNA vaccines often induce lower antibody level and protective efficacy and are still necessary to increase their potency. In this study we evaluated the potency of aluminum phosphate as an adjuvant of DNA vaccines to enhance antibody responses and protective efficacy against botulinum neurotoxin serotypes A and B in Balb/c mice. The administration of these individual and bivalent plasmid DNA replicon vaccines against botulinum neurotoxin serotypes A and B in the presence of aluminum phosphate improved both antibody responses and protective efficacy. Furthermore, formulation of conventional plasmid DNA vaccines encoding the same Hc domains of botulinum neurotoxin serotypes A and B with aluminum phosphate adjuvant increased both antibody responses and protective efficacy. These results indicate aluminum phosphate is an effective adjuvant for these two types of DNA vaccines (i.e., plasmid DNA replicon vaccines and conventional plasmid DNA vaccines), and the vaccine formulation described here may be an excellent candidate for further vaccine development against botulinum neurotoxins.     

重组人乳头瘤病毒核酸疫苗诱导特异性淋巴细胞增殖

采用分子克隆技术 ,将人乳头瘤病毒 16型E7(HPV 16E7)基因重组于真核表达载体上 ,构建了HPV 16E7核酸疫苗。将该疫苗通过皮内注射方式免疫Balb/c纯系小鼠。基因免疫后制备小鼠脾淋巴细胞悬液 ,经体外E7蛋白再次刺激后用MTT比色法检测出了特异性淋巴细胞增殖反应。由于特异性淋巴细胞增殖是反映细胞免疫功能的简便有效方法 ,所以本实验表明HPV 16E7核酸疫苗构建正确 ,并能够诱导机体产生特异性细胞免疫应答     

猪戊型肝炎核酸疫苗的构建及在BAL B/C小鼠免疫效应

将含有kozak序列及BamH I的上游引物和带有终止密码子及EcoRV酶切位点的下游引物,以猪HEVDQ1 ORF2为模板,进行PCR。将扩增片段和pcDNA3.1质粒以BamH I/EcoRV进行双酶切后进行连接。连接产物转化至大肠杆菌DH5α,经测序证明该序列正确,命名为pcDQ1。进行pcDQ1质粒提取,以Vero细胞为表达细胞进行转染,以间接免疫荧光试验进行验证。以100μg/次/只剂量的pcDQ1对BAL B/C小鼠进行免疫以获取单因子血清。共免疫3次,采集血清,进行ELISA效价测定。结果表明,该核酸疫苗可以免疫使小鼠产生抗体。     

Activity of DNA vaccines encoding self or heterologous Her-2/neu in Her-2 or neu transgenic mice

To assess the efficacy of self versus heterologous ErbB-2 vaccines, the reactivity to human and rat ErbB-2 (Her-2 and neu, respectively) DNA vaccines were tested in normal, Her-2 or neu transgenic mice. When immunized with either Her-2 or neu DNA, normal BALB/c and C57BL/6 mice produced cross-reactive T cells, but only antigen specific antibodies. In Her-2 Tg mice, weak to no anti-Her-2 response was induced by either self Her-2 or heterologous neu DNA, demonstrating profound tolerance to Her-2 and the inability to induce anti-Her-2 immunity with either vaccine. In NeuT mice, vaccination with self neu but not heterologous Her-2 DNA induced anti-neu antibodies and delayed spontaneous tumorigenesis. Both neu and Her-2 DNA induced anti-neu T cell response, but depletion of CD8 T cells did not change the delay in tumorigenesis. Therefore, in NeuT mice, both self and heterologous DNA activated anti-neu T cells, although T cell response did not reach sufficient level to suppress spontaneous tumorigenesis. Rather, induction of anti-neu antibodies by self neu DNA is associated with the delay in spontaneous tumor growth. Overall, NeuT mice were more responsive to DNA vaccination than Her-2 Tg mice and this may be associated with the continuous production of neu by the 10 mammary glands undergoing tumor progression.     

DNA疫苗接种的安全性

DNA疫苗的安全性问题主要有三个方面：转入体内的DNA有可能整合到宿主细胞基因组上,使宿主细胞抑癌基因失活或癌基因活化,使宿主细胞转化成癌细胞;外源抗原持续表达产生的不良后果;质粒DNA诱导的自身免疫反应。本综合近年来有关献对DNA疫苗安全性的研究作一概括性介绍。     

GM-CSF在登革热病毒和丙型肝炎病毒DNA疫苗诱导的免疫应答中的作用

研究GM-CSF在DV、HCV等几种黄病毒DNA疫苗诱导的免疫应答中的作用,并分析其作为黄病毒DNA疫苗佐剂的可能性。构建各种真核表达质粒,抽提质粒DNA,分组免疫小鼠,通过ELISA及间接免疫荧光染色检测小鼠血清抗体的动态水平。DV1及DV2prM/E核酸疫苗与GM-CSF质粒共接种的佐剂组小鼠血清抗体水平低于无佐剂的疫苗组,即GM-CSF显示了一定的免疫抑制作用,其中以DV1prM/E核酸疫苗更为显著;而在HCVC及E1蛋白核酸疫苗中,GM-CSF则具有一定免疫增强作用。GM-CSF作为疫苗佐剂,其作用具有复杂的多样性,因抗原的不同可能会呈现免疫提升或免疫抑制,因此选择其作为核酸疫苗佐剂时需慎重。     

含庚型肝炎病毒E2基因片段质粒DNA能诱发相当强烈的体液免疫应答

研究了庚型肝炎病毒E2(HGV E2)基因片段作为DNA疫苗的可行性。将来自于质粒pThioHis-E2编码HGV E2的基因片段(559bp)亚克隆到质粒pCMV-S中,使之和HBsAg基因位于同一阅读框,形成重组质粒pCMV-S-E2。用纯化的质粒pCMV-S-E2 DNA注射到昆明小鼠后腿四头肌中来免疫小鼠,同时用pCMV-S作为对照。间隔14天再加强一次免疫。在加强免疫后的第8天眼眶取血。用E2—GST融合蛋白作为固定化抗原,通过ELISA检测受试小鼠的体液免疫应答。结果表明,用质粒pCMV-S-EDNA免疫的小鼠可以产生很强的体液免疫应答。     

553 例女性宫颈高危型HPV 感染与宫颈病变的相关性研究

目的:研究女性生殖道高危型人乳头瘤病毒(high risk human papilloma virus,hrHPV)感染现状及子宫颈上皮内瘤样病变(cervical intraepithelial neoplasia,CI N)的现患率,并分析该人群年龄与HPV感染及宫颈癌前病变的相关性以及hrHPV病毒载量与宫颈病变之间剂量-效应关系。方法:对553例30岁-78岁有性生活史的女性进行以人群为基础的横断面调查。对所有接受筛查的妇女均行宫颈HPV检测及电子阴道镜下病理活检,并以病理结果作为诊断子宫颈病变的金标准。资料采用EXCEL整理,利用x2检验和非条件Logistic回归分析危险因素和CI N的关系。结果:553例受检对象总体阳性检出率为18.0%。hrHPV感染情况在不同年龄段分布有显著差异,hrHPV病毒载量越高宫颈病变的程度越重。结论:不同年龄段hrHPV感染情况不同,hrHPV病毒载量与宫颈病变之间存在剂量-效应关系。     

Hepatitis E virus DNA vaccine elicits immunologic memory in mice

Injection of an expression vector pJHEV containing hepatitis E virus (HEV) structural protein open reading frame 2 gene generates a strong antibody response in BALB/c mice that can bind to and agglutinate HEV. In this study, we tested for immunologic memory in immunized mice whose current levels of IgG to HEV were low or undetectable despite 3 doses of HEV DNA vaccine 18 months earlier. Mice previously vaccinated with vector alone were controls. All mice were administered a dose of HEV DNA vaccine to simulate an infectious challenge with HEV. The endpoint was IgG to HEV determined by ELISA. Ten days after the vaccine dose, 5 of 9 mice previously immunized with HEV DNA vaccine had a slight increase in IgG to HEV. By 40 days after the vaccine dose, the level of IgG to HEV had increased dramatically in all 9 mice (108-fold increase in geometric mean titer). In contrast, no control mice became seropositive. These results indicate that mice vaccinated with 3 doses of HEV DNA vaccine retain immunologic memory. In response to a small antigenic challenge delivered as DNA, possibly less than delivered by a human infective dose of virus, mice with memory were able to generate high levels of antibody in less time than the usual incubation period of hepatitis E. We speculate that this type of response could protect a human from overt disease.     

青海地区46273例女性宫颈HPV检测结果分析

摘要 目的：根据青海地区妇女宫颈人乳头瘤病毒（HPV）检测结果,分析宫颈高危HPV（HR-HPV）感染分布特点,为指导HPV疫苗接种提供理论依据。方法：采用Hybriuax技术检测21种高危型HPV亚型,对2014年1月-2020年2月于我院就诊的46273例女性宫颈人乳头瘤病毒分型检测。结果：46273例妇女中,高危HPV阳性率10.23%,高危HPV阳性率和年龄之间存在线性趋势,随年龄的增大感染比例上升。单一高危亚型HPV感染前三位的HPV亚型为16、58和39,合计占到45.64%。HPV亚型感染以单高危阳性为主,占总HPV阳性数的88.26%,占全部筛查人数的9.03%。HPV16、58、31、68亚型阳性率和年龄段之间存在线性趋势,随年龄的增大感染比例上升。HPV感染亚型检出构成比各年龄段均以HPV16感染排在第一位,排在第二位除61-70岁为双高危外,均为HPV58为主。结论：青海地区女性HPV感染率较高,以单一高危型感染为主,HPV16、58、39、52是主要的感染亚型,所以应针对青海地区HPV感染状况设计具有针对性的预防HPV感染亚型的疫苗。     

Induction of an antibody response in mice against human papillomavirus (HPV) type 16 after immunization with HPV recombinant Salmonella strains

 Human papillomaviruses (HPV) are present in approximately 95% of all cervical carcinomas and the HPV E6 and E7 genes are continuously expressed in these lesions. There is also circumstantial evidence that often natural immunity against HPV is generated and that this is of influence on HPV-induced lesions. Stimulation of the immune system by proper presentation of relevant HPV antigens might, therefore, lead to a prophylactic or therapeutic immunological intervention for HPV-induced lesions. For this purpose we have expressed the E6 and E7 protein of HPV 16 in an attenuated strain of Salmonella typhimurium (SL3261, aroA mutation), which has been used extensively as a live vector. Live recombinant Salmonella vaccines have the ability to elicit humoral, secretory and cell-mediated immune responses, including cytotoxic T cells, against the heterologous antigens they express. This report describes the construction of recombinant Salmonella strains expressing the HPV 16 E6 and E7 proteins, and the induction of an HPV-16-specific immune response in mice after immunization with these live vectors. Received: 25 June 1996 / Accepted: 6 August 1996     

553例女性宫颈高危型HPV感染与宫颈病变的相关性研究

目的：研究女性生殖道高危型人乳头瘤病毒（high risk human papilloma virus,hrHPV）感染现状及子宫颈上皮内瘤样病变（cervical intraepithelial neoplasia,CI N）的现患率,并分析该人群年龄与HPV感染及宫颈癌前病变的相关性以及hrHPV病毒载量与宫颈病变之间剂量-效应关系。方法：对553例30岁-78岁有性生活史的女性进行以人群为基础的横断面调查。对所有接受筛查的妇女均行宫颈HPV检测及电子阴道镜下病理活检,并以病理结果作为诊断子宫颈病变的金标准。资料采用EXCEL整理,利用x2检验和非条件Logistic回归分析危险因素和CI N的关系。结果：553例受检对象总体阳性检出率为18.0%。hrHPV感染情况在不同年龄段分布有显著差异,hrHPV病毒载量越高宫颈病变的程度越重。结论：不同年龄段hrHPV感染情况不同,hrHPV病毒载量与宫颈病变之间存在剂量-效应关系。     

高危型HPV检测在宫颈ASCUS分流及随访中的应用

目的:分析高危型人乳头瘤病毒(HPV)检测对宫颈非典型鳞状上皮细胞(ASCUS)患者分流管理的作用,提高分流管理合理性。方法:对200例经液基薄层细胞学(TCT)检查确诊为ASCUS患者采用荧光定量聚合酶链反应技术(FQPCR)检测HPV分型,并进行病理活检。观察高位型HPV阳性率及分型及其与宫颈病变的关系。结果:200例患者中有101例检出高危型HPV阳性,阳性率为50.50%;病理活检确诊正常或炎症、宫颈上皮内瘤变(CIN)Ⅰ级、CINⅡ~Ⅲ级、鳞状细胞癌各有114例、32例、51例、3例,分别占57.00%、16.00%、25.50%、1.50%,高危型HPV阳性率分别为18.42%、87.50%、96.08%、100.00%,≥CINII级病变患者高危型HPV阳性率高于CINⅡ级组,差异比较有显著性(P0.05)。结论:高危型HPV检测可为宫颈ASCUS的合理分流提供可靠依据。