Novel TLR Ligand Mimetics as Adjuvants and Therapeutics

作为佐剂和治疗药物的新型 TLR 配体模拟物

• 批准号: 6853546
• 负责人: MICHAEL D GUNN
• 金额: $ 96.46万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-08-15 至 2008-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6853546
• 关键词: antibody; biotechnology; cooperative study; immunologic substance development /preparation; immunomodulators; toll like receptor

DESCRIPTION (provided by applicant): Conjugation of antigens to molecules that bind receptors expressed on dendritic cells (DC) has been shown to increase immunogenicity in several ways: 1) DC targeting increases Ag delivery to DC 100-1000 fold; 2) targeting receptors that activate DC provides co-stimulatory signals that mimic the effects of traditional non-specific adjuvants; 3) because such receptors are pathogenic-specific, their activation results in immune responses that mimic that of natural infection. Although proven in concept, a practical method of targeting antigens to DC-activating receptors does not currently exist. Toll-like receptors (TLRs) are the major class of DC-activating receptors and have been shown to mediate the effects of all currently used adjuvants. Our proposal is to develop molecules that bind to TLRs with high affinity to simultaneously target and activate DC, thus providing a strong antigen-specific immune stimulus. To identify TLR-binding molecules, single-chain antibody (scFv) libraries will be screened against the purified extracellular domains of all known TLRs. Previous screens by our group have identified large numbers of scFvs that bind to cell surface receptors with high affinity. Such scFvs can be re-engineered as humanized monoclonal antibodies or otherwise manipulated and fused or conjugated to specific antigens. Once identified, candidate scFvs will be tested for their ability to bind TLRs, to bind DC, to target antigens to DC, to activate DC, and to inhibit the activation of DC by natural TLR ligands. (As proposed, our screens are likely to identify scFvs that function as TLR inhibitors.) Those molecules that prove effective in targeting and activating DC will be fused to model antigens derived from anthrax, vaccinia and Yersinia and tested in vivo for their ability to stimulate antibody production, CTL responses, and protective immunity against lethal challenge after systemic and nasal immunization. The primary aim of the proposal is to develop single chain antibodies that: 1) bind specifically to individual toll-like receptors; 2) can be complexed to antigens; 3) target Ag to Ag-presenting cells; 4) activate Ag-presenting cells; 5) stimulate strong Ag-specific immune responses; and 6) provide protective immunity to toxin or pathogen challenge. Once validated, such molecules should be generally applicable as an adjuvant platform by their conjugation or fusion to any protein Ag.

描述（由申请人提供）：抗原与在树突细胞（DC）结合受体（DC）结合的分子的结合已证明可以通过多种方式增加免疫原性：1）DC靶向靶向DC的AG递送到DC 100-1000倍； 2）激活DC的靶向受体提供了模仿传统非特异性佐剂影响的共刺激信号； 3）由于这种受体是致病性特异性的，因此它们的激活会导致模仿自然感染的免疫反应。尽管在概念上得到证明，但目前尚不存在将抗原靶向DC激活受体的实用方法。 Toll样受体（TLR）是DC激活受体的主要类别，已被证明可以介导所有当前使用的佐剂的作用。我们的建议是开发与同时靶向和激活DC的高亲和力结合的分子，从而提供强大的抗原特异性免疫刺激。为了鉴定TLR结合分子，将对所有已知TLR的纯化细胞外域进行筛选单链抗体（SCFV）文库。我们组的先前筛选已经确定了大量与具有高亲和力的细胞表面受体结合的SCFV。可以将这种SCFV重新设计为人源化的单克隆抗体，或者在其他方式进行操纵，融合或结合到特定抗原中。一旦确定，候选SCFV将测试其结合TLR，结合DC，将抗原靶向DC，激活DC并抑制天然TLR配体DC激活的能力。 (As proposed, our screens are likely to identify scFvs that function as TLR inhibitors.) Those molecules that prove effective in targeting and activating DC will be fused to model antigens derived from anthrax, vaccinia and Yersinia and tested in vivo for their ability to stimulate antibody production, CTL responses, and protective immunity against lethal challenge after systemic and nasal immunization.该提案的主要目的是开发：1）专门与单个Toll样受体结合的单链抗体； 2）可以使抗原复合； 3）靶向Ag to Ag呈现细胞； 4）激活呈递Ag的细胞； 5）刺激强大的AG特异性免疫反应； 6）对毒素或病原体挑战提供保护性免疫。一旦得到验证，这种分子通常应通过其结合或融合到任何蛋白质Ag的结合或融合为辅助平台。