Enhancing HPV-16 E6/E7 Specific Antitumor Immunity

描述(由申请人提供)：预防性人类乳头瘤病毒(HPV)疫苗无法消除现有的HPV感染和相关病变，这是一个严重的问题，因为全球有相当大的HPV相关宫颈癌病例负担。仍然迫切需要开发治疗性HPV疫苗来控制宫颈癌。由于HPV早期蛋白E6和E7在大多数宫颈癌中持续表达，并与其恶变有关，因此它们是治疗性HPV疫苗的理想靶点。DNA疫苗是一种很有前途的方法，可以产生针对E6/E7表达的肿瘤或病变的抗原特异性T细胞免疫。很明显，裸露DNA疫苗在患者体内的免疫原性较差，反映了抗原基因向专业抗原呈递细胞，特别是树突状细胞(DC)的低效传递。因此，挑战是开发一种方法，有效地将治疗性HPV DNA输送到患者的DC中，以触发细胞毒性T细胞免疫，而不存在与活载体相关的安全问题。 我们最近介绍了使用传染性乳头瘤病毒假病毒粒子作为一种新的方法来改进体内裸露DNA疫苗的递送。最新的技术使我们能够产生高滴度的传染性乳头瘤病毒假病毒用于疫苗接种。因此，传染性乳头状瘤病毒假病毒粒子代表了一种创新的、有前途的DNA疫苗递送系统，以触发针对癌症的强大免疫反应。具体地说，我们计划的目标1：优化DNA在小鼠皮肤角质形成细胞、朗格汉斯细胞和/或真皮树突状细胞中的转导，方法是在皮肤屏障破坏后，通过感染携带标记基因的亲皮型HPV-2/4假病毒粒子，使用激光表面重铺、胶带剥离或晶体微晶磨削术。目的：研究携带治疗性HPV DNA的嗜皮性假病毒粒子经优化皮肤给药后对C57BL/6小鼠的HPV-16E6/E7特异性免疫应答和抗肿瘤作用。目的：研究携带治疗性HPV DNA的嗜皮性假病毒粒子对E6/E7表达的小鼠肿瘤模型的治疗作用机制。目的：研究嗜皮性假病毒载体携带的治疗性HPVDNA疫苗与肿瘤微环境免疫调节因子(S)联合应用对已建立的表达HPVE6/E7的肿瘤的控制作用。 公共卫生相关性：我们的研究将创建一种创新的、无针皮肤接种策略，以携带治疗性HPV DNA疫苗的嗜皮性乳头瘤病毒假病毒粒子感染，遵循优化的皮肤屏障破坏技术来控制HPV相关损害。本研究的成功实施将带来一个新的疫苗技术平台，该平台可以结合DNA疫苗接种的安全性和病毒载体介导的高效体内基因传递的优势，开发针对HPV和其他慢性病毒感染的有效治疗性疫苗。因此，我们的方法具有非常重要的意义，因为它可能使世界各地患有慢性HPV感染和HPV相关疾病的大量患者受益，并极大地促进我们对病毒相关肿瘤的免疫治疗的了解。

DESCRIPTION (provided by applicant): The inability of preventive human papillomavirus (HPV) vaccines to eliminate existing HPV infections and associated lesions is a serious concern since there is a considerable burden of HPV-related cervical cancer cases worldwide. There remains a pressing need to develop therapeutic HPV vaccines to control cervical cancer. Since HPV early proteins E6 and E7 are constantly expressed in a majority of cervical cancers and are responsible for their malignant transformation, they represent ideal targets for therapeutic HPV vaccine. DNA vaccine has emerged as a promising approach to generate antigen-specific T cell immunity against E6/E7- expressing tumors or lesions. It has become apparent that the poor immunogenicity of naked DNA vaccines in patients reflects inefficient delivery of the antigenic gene to professional antigen-presenting cells, particularly dendritic cells (DCs). Thus, the challenge is to develop an approach to efficiently deliver therapeutic HPV DNA into DCs of patients to trigger cytotoxic T cell immunity, without the safety concerns related to live vectors. We have recently introduced the use of infectious papillomavirus pseudovirions as a novel approach to improve naked DNA vaccine delivery in vivo. The latest technology has enabled us to generate high titers of infectious papillomavirus pseudovirions for vaccination. Thus, infectious papillomavirus pseudovirions represent an innovative and promising delivery system for DNA vaccine to trigger potent immune responses against cancer. Specifically, we plan to Aim 1: Optimize DNA transduction of mouse keratinocytes, Langerhans cells and/or dermal DCs in mouse skin by infection with skin-tropic HPV-2/4 pseudovirions carrying a marker gene after skin barrier disruption using laser resurfacing, tape stripping or crystal microdermabrasion. Aim 2: Characterize the HPV-16 E6/E7-specific immune responses and antitumor effects in C57BL/6 mice infected with skin-tropic pseudovirions carrying therapeutic HPV DNA following optimized cutaneous delivery. Aim 3: Characterize the mechanisms of the therapeutic antitumor effects against an E6/E7-expressing tumor model in mice treated with cutaneous vaccination of skin-tropic pseudovirions carrying therapeutic HPV DNA. Aim 4: Characterize the combination of therapeutic HPV DNA vaccine delivered by skin-tropic pseudovirions with tumor microenvironment immune modulating factor(s) for the control of established HPV E6/E7-expressing tumors. PUBLIC HEALTH RELEVANCE: Our study will create an innovative, needle-free cutaneous vaccination strategy of infection with skin-tropic papillomavirus pseudovirions carrying therapeutic HPV DNA vaccine following an optimized skin barrier-disrupting technique for the control of HPV-associated lesions. The successful implementation of our proposed study will lead to a new platform of vaccine technology that can combine the advantages of safety of DNA vaccination and efficient in vivo gene delivery mediated by viral vectors for the development of effective therapeutic vaccines for HPV and other chronic viral infections. Thus, our approach is highly significant as it may benefit a large population of individuals suffering from chronic HPV infections and HPV-associated disease all over the world and greatly advance our knowledge of immunotherapy for virus-associated tumors.