T-cell receptor mimic affinity reagent generation using an in vivo novel immunogen strategy

摘要 目前的治疗性抗体靶向细胞表面和外部细胞环境内。然而 细胞内蛋白质占蛋白质组的一半。有一种简单的方法， 用于产生治疗性抗体的蛋白质将是非常需要的。靶向MHC复合物 与来自细胞内蛋白质的新抗原结合将极大地允许产生T细胞受体模拟物， 用于开发作为治疗药物的TCRm抗体。我们开发了一种独特的免疫靶向 我们称之为“Epivolve”的策略，可用于通过利用 Ab的互补决定区（CDR）-H2。Epivolve的功能是通过一个 抗体互补位使用的方法中所描述的建议。体内方法的优点 所提出的方法包括分离对抗体具有高亲和力（在低皮摩尔范围内）的抗体。 肽：MHC复合物。这是因为Ab可以经历多次Ag挑战和亲和力成熟， 体内体细胞超突变产生个位数pM至百分之一nM的抗体。体内 方法也可以利用转基因动物来衍生人Ab。TCRm抗体的亲和力 通过噬菌体展示产生的噬菌体抗体倾向于处于中等纳摩尔范围（100 -300 nM），并且需要 进一步的体外蛋白质工程。对于这项提议，Abbratech将采用其新颖的现场指导Epivolve 技术沿着改进的兔单B细胞分选平台，用于有效发现TCRm ABS. Epivolve方法克服了公差。我们的目标之一就是在尽可能短的时间内 5周。高亲和力新抗原：已证明难以大规模生产MHC特异性TCR m Ab 通过传统的噬菌体或杂交瘤方法获得数量。增强技术， 短时间内的TCRm抗体为加速未来TCRm抗体的发现提供了令人兴奋的机会。

ABSTRACT Current therapeutic antibodies target the cell surface and within the external cellular environment. Yet intracellular proteins make up half of the proteome. Having a facile means of targeting those intracellular proteins for the generation of therapeutic antibodies would be highly desirable. Targeting MHC complexed with neoantigens from intracellular proteins would greatly allow the generation of T cell receptor mimic (TCRm) antibodies for development as therapeutic drugs. We have developed a unique immune-targeting strategy that we call ‘Epivolve’ that can be used to make ‘site directed’ Abs by leveraging the modularity of the complementarity determining region (CDR)-H2 of an Ab. Epivolve functions through the ‘evolution’ of an Ab paratope using methods that are described in the proposal. The advantages of the in vivo method proposed include the isolation of Abs that have a high affinity (in the low picomolar range) for the peptide:MHC complex. This is because Abs can undergo multiple Ag challenges and affinity maturation via somatic hyper-mutagenesis in vivo to generate antibodies with single digit pM to hundredth nM. In vivo methods can also take advantage of transgenic animals for deriving human Abs. Affinities of TCRm Abs produced through phage display tend to lie in the moderate nanomolar range (≈50–300 nM) and require further in vitro protein engineering. For this proposal, Abbratech will apply its novel site-directed Epivolve technology along with an improved rabbit single B cell sorting platform for the efficient discovery of TCRm Abs. The Epivolve method overcomes tolerance. And one of our goals is to generate antibodies in as little as 5 weeks. High-affinity, neoantigen:MHC-specific TCRm Abs have proven difficult to produce in large numbers by either traditional phage or hybridoma approaches. Enhanced technologies for the generation of TCRm Abs within a short period of time offer exciting opportunities to accelerate future TCRm Ab discovery.