Therapeutic Vaccine for HIV/HPV-associated Oropharyngeal and Tonsillar Malignanci

描述（由申请人提供）：该项目的目标是基于HPV在发病机制中的作用，开发一种治疗hb| v相关恶性肿瘤的策略。HPV相关肿瘤表达HPV的E6/E7癌蛋白，是免疫诱导疫苗的理想靶点。我们将开发一种基于新型腺病毒血清型s载体（Ads）平台的疫苗，该平台具有独特和额外的病毒DNA聚合酶和早期基因2b （E2b）区域的前端蛋白缺失（Ads [E1-, E2b-]）。在使用HIV抗原的研究中，我们报道了新的Ad5 [E1-， E2b-]- hlv载体疫苗在多重免疫方案中诱导CMI应答时优于当前的Ads [E1-]- h |V载体疫苗（包含早期基因1 （E1）区域的缺失）。尽管存在预先存在的ad免疫，但在小鼠和猴子中诱导了显著的抗原特异性CMI反应。我们将构建和生产AdS [E1-， E2b-]载体疫苗，该疫苗含有具有非致瘤功能的HPV癌蛋白E6/E7。该重组腺病毒通过直接转染抗原提呈细胞，表达修饰后的HPV-E6/E7抗原，诱导免疫应答。我们将对其与toll样受体激动剂（TLRa）联合进行评估，TLRa旨在增强疫苗诱导的免疫反应。我们的临床前数据表明，即使存在预先存在的AdS免疫，AdS [E1-， E2b-] vec*or也能诱导针对肿瘤相关抗原（fAA）的强大CMI应答。在采用癌胚抗原（CEA）基因插入的小鼠肿瘤模型中，比较了1个新AdS [E1-， e2b - 1- GEA]重复免疫的t1 .g -CEA的免疫原性和体内抗肿瘤作用。这些AdS载体在临床相关的AdS免疫环境中进行了测试。我们观察到，多次免疫AdS [E1-， E2b-]- cea的AdS免疫小鼠诱导的cea特异性CMI反应明显高于多次免疫当前一代AdS tE1-l-CEA的AdS免疫小鼠。与Ads [E1- i- CEA]处理的小鼠相比，Ads [E1-， E2b-J-CEA处理的带有CEA表达肿瘤的Ads免疫小鼠具有更高的抗肿瘤反应。这些结果表明，尽管存在预先存在的AdS免疫，但AdS [E1-， Ezb-l-CEA可以诱导CMI免疫反应，导致肿瘤生长抑制。我们还利用表达TAA HER2lneu的Ads [E1-， Ezb-]载体平台作为乳腺癌免疫治疗剂。在Ad5免疫小鼠中，Ads [E1-， E2b-l-HERZlneu诱导了针对HER2/neu的强效CMI，并显著抑制了已建立肿瘤的进展。这些数据表明，在AdS免疫动物体内传递表达TM的Ad5 [E1-， E2b-]载体可以诱导抗taa免疫并抑制肿瘤进展。

DESCRIPTION (provided by applicant): The objective of this project is to develop a therapeutic strategy for H|V-associated malignancy based on the role of HPV in the pathogenesis. HPV related cancers express the E6/E7 oncoproteins of HPV that are ideal targets for immune inducing vaccines. We will develop a vaccine based upon a novel adenovirus serotype-S vector (Ads) platform with unique and additional deletions of the viral DNA polymerase and the pre- terminal protein in the early gene 2b (E2b) region (Ads [E1-, E2b-]). In studies employing HIV antigens, we reported that the new Ad5 [E1-, E2b-]-HlV vector vaccine was superior to a current Ads [E1-]-H|V vector vaccine (containing deletion in the early gene 1 (E1) region) when used to induce CMI responses in a multiple immunization regimen. Significant antigen specific CMI responses were induced in mice and monkeys despite the presence of pre-existing AdS immunity. We will construct and produce an AdS [E1-, E2b-] vector vaccine that contains the HPV oncoproteins E6/E7 with non-oncogenic function. This new recombinant adenovirus will induce immune responses by expressing the modified HPV-E6/E7 antigens after direct transfection of antigen presenting cells. We will evaluate this in combination with a toll-like receptor agonist (TLRa) designed to enhance immune responses induced by the vaccine. Our pre-clinical data indicate that the AdS [E1-, E2b-] vec*or induces robust CMI responses against tumor associated antigen [fAA), even in the presence of pre- existing AdS immunity. In a murine cancer model employing the carcinoembryonic antigen (CEA) gene insert, tl.g -CEA immunogenicity and in vivo anti-tumor effects of repeated immunizations with i new AdS [E1-, E2b-l- GEA were compared to those observed with a current generation Ads tE1-l-CEA. These AdS vectors were tested in a clinically relevant AdS immune setting. We observed that AdS immune mice immunized multiple times with AdS [E1-, E2b-]-CEA induced CEA-specific CMI responses that were significantly increased over those detected in AdS immune mice immunized multiple times with a current generation AdS tE1-l-CEA. Ads immune mice bearing CEA expressing tumors that were treated with AdS [E1-, E2b-J-CEA had an increased anti-tumor response as compared to AdS [E1-I-CEA treated mice. These results demonstrate that AdS [E1-, Ezb-l-CEA can induce CMI immune responses that result in tumor growth inhibition despite the presence of pre-existing AdS immunity. We have also utilized the Ads [E1-, Ezb-] vector platform expressing the TAA HER2lneu as a breast cancer immunotherapeutic agent. Ads [E1-, E2b-l-HERZlneu induced potent CMI against HER2/neu and significantly inhibited progression of established tumors in Ad5 immune mice. These data demonstrate that in vivo delivery of Ad5 [E1-, E2b-] vectors expressing TM can induce anti-TAA immunity and inhibit progression of tumors in AdS immune animals. PUBLIC HEALTH RELEVANCE: In this study, we will develop a new adenoviral based drug (AdS [E1-, E2b-I-HPV-E6/7) to treat HtV+ patients with HPv-associated oropharyngeal and tonsillar ,ncers. The treatment platform is needed to overcome pre-existing AdS immunity that has prevented the widespread use of this type of technology.