SBIR Phase I: A platform for identifying antibodies that modulate human membrane receptors involved in disease

这个小企业创新研究（SBIR）项目的更广泛的影响/商业潜力是能够发现没有可用治疗方法的疾病所需的抗体疗法。这些疗法通过增加或减少一种类型的细胞信号受体“G蛋白偶联受体”（GPCR）的活性来起作用。抗体对其靶标具有高度特异性，这是GPCR药物的重要特征，因为GPCR包含结构相似的蛋白质的大家族。 事实上，用于GPCR的小分子药物通常是有毒的，这是由于作用于结构相似但功能不相关的GPCR的副作用。该项目将开发第一种通过调节GPCR功能的能力直接识别抗体的技术。这些抗体将通过治疗目前无法治愈的疾病来影响社会健康，并通过研究GPCR相关的哺乳动物生理学和疾病来强烈影响科学理解。商业影响可能非常大。全球GPCR药物市场超过1000亿美元，超过一半的上市抗体治疗药物的年销售额超过10亿美元。该平台具有开发多种GPCR抗体疗法的潜力，从而为患者、整个社会和共同开发伙伴创造巨大价值。SBIR第一阶段项目提出开发一个发现GPCR调节抗体的平台。该平台对于生成用于研究GPCR相关生物学和疾病的工具以及开发比小分子药物副作用更少的治疗GPCR相关疾病的疗法至关重要。使用传统方法开发功能性GPCR抗体受到难以产生代表处于功能状态的GPCR的抗原以及缺乏GPCR功能的高通量测定的阻碍。所提出的平台和方法在酿酒酵母中表达人GPCR，将活性与可选择的表型偶联，并直接选择在相同细胞中调节GPCR功能的抗体。第一个目的旨在进一步表征抑制内源性酵母GPCR、Ste2的骆驼抗体（"纳米抗体"）拮抗剂的活性和特异性，然后进行激动剂选择以鉴定至少一种Ste2激动剂。第二个目的旨在进一步开发平台，以使得能够使用ScFv抗体文库询问更广泛的人GPCR靶标，并鉴定治疗相关的人GPCR的至少一种激动剂或拮抗剂。积极的结果将证明该平台的可行性。

The broader impact/commercial potential of this Small Business Innovation Research (SBIR) project is to enable the discovery of needed antibody therapeutics in diseases for which there are no available treatments. These therapies act by increasing or decreasing the activity of a type of cell signaling receptor, "G protein-coupled receptors" (GPCRs). Antibodies are highly specific for their targets, an important characteristic for GPCR drugs, as GPCRs comprise a large family of structurally similar proteins. In fact, small molecule drugs for GPCRs often are toxic due to side effects from acting on structurally similar but functionally unrelated GPCRs. This project will develop the first technology that directly identifies antibodies by their ability to modulate GPCR function. These antibodies will impact society's health by treating currently incurable diseases, and strongly impact scientific understanding by enabling the study of GPCR-related mammalian physiology and disease. The commercial impacts are potentially very large. The global GPCR drug market is over $100B, and over half of marketed antibody therapeutics have annual sales of over $1B. The platform described here has the potential to develop many GPCR antibody therapeutics, and thereby generate an enormous amount of value for patients, society at large, and co-development partners.This SBIR Phase I project proposes to develop a platform for discovering GPCR-modulating antibodies. This platform could be critical for generating tools for studying GPCR-related biology and disease, and for developing therapeutics with fewer side effects than small molecule drugs to treat GPCR-related diseases. Developing functional GPCR antibodies using traditional methods is encumbered by the difficulty in producing antigens that represent the GPCR in a functional state, and a lack of high-throughput assays of GPCR function. The proposed platform and method expresses human GPCRs in Saccharomyces cerevisiae yeast, couples activity to selectable phenotypes, and directly selects antibodies that modulate GPCR function in the same cells. The first objective aims to further characterize the activity and specificity of camelid antibodies ("nanobodies") antagonists that inhibit the endogenous yeast GPCR, Ste2, and then perform agonist selections to identify at least one Ste2 agonist. The second objective aims to further develop the platform to enable interrogating a broader array of human GPCR targets using ScFv antibody libraries, and to identify at least one agonist or antagonist of a therapeutically relevant human GPCR. Positive results will demonstrate the feasibility of the platform.