Human studies of Listeria monocytogenes vectors

单核细胞增生李斯特氏菌载体的人体研究

• 批准号: 6900997
• 负责人: ELIZABETH L. HOHMANN
• 金额: $ 39.38万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-06-15 至 2007-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6900997
• 关键词: Listeria; attenuated microorganism; bacterial vaccines; biotechnology; cellular immunity; chimeric proteins; clinical research; clinical trials; dosage; drug screening /evaluation; enzyme linked immunosorbent assay; experimental designs; flow cytometry; gag protein; genetic manipulation; genetic strain; human subject; immunotherapy; laboratory mouse; molecular cloning; tissue /cell culture; transfection /expression vector; vaccine development; vector vaccine

DESCRIPTION: (Provided by Applicant) Listeria monocytogenes are Gram-positive intracellular bacteria which stimulate cellular immune responses, those necessary for elimination of viruses. Engineered L. monocytogenes are effective vaccine vectors for delivery of both viral and tumor antigens in animals. Both therapeutic and prophylactic approaches are successful in animals. Listeria spp. Are present in foods, enter the body through the intestine and may disseminate to cause serious infection with a tropism for the central nervous system and placenta. Safety is therefore a major consideration in use of L. monocytogenes as a vector in humans. We have initiated (to our knowledge) the first safety study of a live attenuated L. monocytogenes vector organism in human volunteers. A highly attenuated derivative of L. monocytogenes 10403S deleted for the virulence elements actA and plcB is being studied. There have been no serious adverse events to date in 18 volunteers who received single oral escalating doses of this attenuated strain (10E5 to 10E9 colony forming units). This proposal sets forth a plan for ongoing evaluation of Listeria bacteria as vaccine vectors in humans. Attenuated L. monocytogenes will be engineered to express defined influenza A and HIV Gag epitopes as secreted fusion proteins of listeriolysin. Strains constructed will be evaluated bacteriologically, in mice and in tissue culture systems. Promising strains will be carried on for evaluation in small inpatient clinical studies designed to evaluate safety, shedding and human immunogenicity. Contemporary immunological studies using tetramer, FACS and ELISPOT technologies will be used to determine whether discrete human cellular immune responses to vectored viral antigens can be detected in humans after these investigational immunizations. These studies will provide important data on the feasibility and utility of using Listeria monocytogenes vectors in humans.

描述：(申请人提供)单核细胞增多性李斯特菌革兰氏阳性 刺激细胞免疫反应的细胞内细菌，那些 对于消除病毒来说是必要的。基因工程的单核细胞增多性乳杆菌是有效的 用于在动物体内传递病毒和肿瘤抗原的疫苗载体。两者都有 治疗和预防方法在动物身上是成功的。李斯特菌 SPP.存在于食物中，通过肠道进入体内，并可能 传播引起严重的中枢神经偏向性感染 系统和胎盘。因此，安全是使用L。 单核细胞增多症作为人类的载体。我们已经(据我们所知)发起了 首次对减毒活的单核细胞增多性乳杆菌载体生物体进行安全性研究 人类志愿者。单核细胞增多性乳杆菌10403S的高度减毒衍生物 对毒力元件ActA和PLCB的删除正在研究中。有 到目前为止，在18名接受单次注射的志愿者中没有严重的不良反应 口服递增剂量的该减毒菌株(10E5至10E9集落形成 单位)。该提案提出了对李斯特氏菌进行持续评估的计划。 细菌在人类体内作为疫苗载体。减毒的单核细胞增多性乳杆菌 经改造后可分泌表达特定的甲型流感和HIV Gag表位 李斯特菌溶血素的融合蛋白。将对构建的菌株进行评估 在细菌学上，在小鼠和组织培养系统中。有希望的菌株 将在设计的小型住院临床研究中进行评估 评价其安全性、脱落性和人体免疫原性。当代 将使用四聚体、流式细胞仪和ELISPOT技术进行免疫学研究 用于确定离散的人类细胞免疫反应是否向载体 在这些研究之后，可以在人类身上检测到病毒抗原 免疫接种。这些研究将提供有关可行性和 单核细胞增多性李斯特氏菌载体在人类中的应用。