FLP-102: Rationally Engineered Antiviral Protein

FLP-102：合理工程设计的抗病毒蛋白

• 批准号: 6590069
• 负责人: OSMOND J D'CRUZ
• 金额: $ 10万
• 依托单位: PARADIGM PHARMACEUTICALS, LLC
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-05-01 至 2004-10-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6590069
• 关键词: angiosperms; antiAIDS agent; antiviral agents; biotherapeutic agent; drug design /synthesis /production; drug screening /evaluation; human immunodeficiency virus 1; laboratory mouse; medicinal plants; pharmacokinetics; plant proteins; protein engineering; recombinant proteins

DESCRIPTION (provided by applicant): Pokeweed antiviral protein (PAP) is a 29-kDa naturally occurring antiviral agent that can be isolated from the leaves of the pokeweed plant, Phytolacca americana. PAP has a unique ability to depurinate HIV-I RNA. PAP exhibits potent antiviral activity against drug-resistant primary clinical HIV-1 isolates. Both zidovudine (ZDV)-sensitive and ZDV-resistant clinical HIV- 1 isolates were found to be > 4 log more sensitive to PAP than to ZDV. We have cloned the gene for PAP and established procedures for large-scale production and purification of the cloned recombinant pokeweed antiviral protein. We have tested recombinant PAP against a broad panel of viruses in vitro and documented that it is as active as native PAP against both DNA and RNA viruses. We were also able to determine the X-ray crystal structure of pokeweed antiviral protein at 2.1A resolution. More recently, we have used a molecular model of PAP-HIV RNA interactions for the rational design of PAP mutants with potent anti-HIV activity. Two such recombinant PAP proteins, FLP- 102 (151AA 152) and FLP- 105 (191AA 192) have been engineered, produced, and tested both in vitro as well as in vivo. These proteins depurinate HIV-1 RNA much better than ribosomal RNA and are more potent anti-HIV agents than native PAP or recombinant wild-type PAP. Our preliminary studies indicate that the rationally engineered FLP-102 exhibits potent in vivo anti-HIV activity against a genotypically and phenotypically NRTI-resistant clinical HIV-1 isolate in a surrogate Hu-PBL-SCID mouse model of human AIDS. We hypothesize that FLP-102, because of its potent in vitro and in vivo anti-HIV activity may provide the basis for effective salvage therapies for patients harboring highly drug-resistant strains of HIV-1. The goal of this Phase I proposal is: (i) to study the broad-spectrum anti-HIV activity of rationally designed recombinant PAP protein FLP-102; and (ii) to study the in vivo toxicity profile and pharmacokinetic and pharmacodynamic features of FLP-102 in mice. The preclinical data on FLP-102 will be essential to further explore the utility of this novel recombinant PAP mutant for Phase II.

描述（由申请人提供）：商陆抗病毒蛋白（PAP）是一种 29-kDa 天然存在的抗病毒剂，可以从商陆植物美洲商陆的叶子中分离出来。 PAP具有独特的脱嘌呤HIV-1 RNA的能力。 PAP 对耐药的主要临床 HIV-1 分离株表现出有效的抗病毒活性。发现齐多夫定(ZDV)敏感和ZDV抗性临床HIV-1分离株对PAP的敏感度比对ZDV的敏感度高4个对数以上。我们克隆了PAP基因，并建立了克隆的重组美洲商陆抗病毒蛋白的大规模生产和纯化程序。我们在体外针对多种病毒测试了重组 PAP，并证明其与天然 PAP 一样具有针对 DNA 和 RNA 病毒的活性。我们还能够以 2.1A 分辨率确定美洲商陆抗病毒蛋白的 X 射线晶体结构。最近，我们使用 PAP-HIV RNA 相互作用的分子模型来合理设计具有有效抗 HIV 活性的 PAP 突变体。两种这样的重组 PAP 蛋白 FLP-102 (151AA 152) 和 FLP-105 (191AA 192) 已在体外和体内进行了工程设计、生产和测试。这些蛋白质对 HIV-1 RNA 的脱嘌呤作用比核糖体 RNA 好得多，并且是比天然 PAP 或重组野生型 PAP 更有效的抗 HIV 药物。我们的初步研究表明，合理设计的 FLP-102 在人类艾滋病替代 Hu-PBL-SCID 小鼠模型中对基因型和表型耐药的临床 HIV-1 分离株表现出有效的体内抗 HIV 活性。我们假设 FLP-102 由于其有效的体外和体内抗 HIV 活性，可能为携带高度耐药 HIV-1 菌株的患者提供有效挽救治疗的基础。该一期提案的目标是：（i）研究合理设计的重组 PAP 蛋白 FLP-102 的广谱抗 HIV 活性； (ii) 研究 FLP-102 在小鼠体内的毒性特征以及药代动力学和药效学特征。 FLP-102 的临床前数据对于进一步探索这种新型重组 PAP 突变体在 II 期试验中的效用至关重要。