Intracellular targeting of Tau-specific single domain antibodies

Tau蛋白是癌症和神经退行性疾病中常见的病理生理学参与者，并且总体上是重要的治疗靶标。Tau主要被称为细胞溶质微管相关蛋白，其聚集成细丝，导致在称为Tau病的病理状况下的神经变性。除了微管动力学，Tau的生理作用还包括在细胞核损伤后保护和修复DNA。然而，Tau再表达在癌症治疗期间引起对化疗或放疗的抗性。NanoTarget项目的主要目标是开发新的基于抗体的工具，用于Tau的细胞内靶向，以调节蛋白质与其伴侣的结合。在NanoTarget项目中，法国和德国的项目合作伙伴将联合收割机结合他们在生物化学，结构生物学，生物化学和分子生理学方面的专业知识，以产生细胞可渗透的Tau特异性纳米抗体（Nbs），用于活细胞中的生物学评估，包括神经元。我们将实现与癌症和神经变性相关的应用，从而需要在细胞内的特定位置递送Nbs，以到达病理学的核心。我们假设Tau特异性Nbs可以防止Tau在一系列称为Tau病的相关病理学（包括阿尔茨海默病）中在神经元内的自关联。此外，基于我们工程化Nbs用于隔室特异性细胞递送的能力，我们计划调节核Tau功能。 这些可渗透细胞的Tau特异性Nbs将被化学修饰以监测它们在细胞中的位置，从而为生物学和生物医学研究提供新的工具。NanoTarget的最终目标是提供前所未有的基于Tau特异性纳米抗体的模式，其作为生物研究工具和下一代生物制药的潜力尚未得到满足。NanoTarget将支持我们在竞争激烈的tau蛋白病领域的研究，同时也扩展了我们在癌症领域的原始进展。迄今为止，几乎没有研究过用免疫学方法到达细胞内的Tau的潜力。活细胞中功能蛋白的细胞内递送对于NanoTarget至关重要，在分子生命科学中确实是一项具有挑战性的任务，但它可能对新药的开发非常强大。在这种情况下，要解决的关键因素包括稳定性，细胞渗透性，和药理学效力的交付的蛋白质，同时保持其功能特性。该项目实现这一雄心勃勃目标的可行性得到了申请人在蛋白质化学，特别是细胞渗透性Nb工程，结构生物学，细胞生物学方面的成熟专业知识，他们在Tau研究中的良好记录以及他们之前的成功合作的支持。

The Tau protein is a common pathophysiological player in cancers and neurodegenerative diseases and, overall, an important therapeutic target. Tau is mainly known as a cytosolic microtubule-associated protein that aggregates into filaments leading to neurodegeneration in pathological conditions referred to as tauopathies. In addition to microtubule dynamics, Tau’s physiological roles also include the protection and reparation of DNA following damage in the nucleus. However, Tau re-expression causes resistance to chemo- or radiotherapy during cancer treatment. The primary goal of the proposal NanoTarget is to develop new antibody-based tools for the intracellular targeting of Tau to modulate the protein’s binding to its partners.Within NanoTarget, the French and German project partners will combine their expertise in biological chemistry, structural biology, biochemistry and molecular physiology to generate cell-permeable Tau-specific nanobodies (Nbs) for their biological evaluation in living cells, including neurons. We will enable applications related to cancer and neurodegeneration, thus requiring delivery of the Nbs at a specific location inside the cell, to reach the core of the pathology. We hypothesize that Tau-specific Nbs could prevent Tau self-association inside neurons in a series of related pathologies called tauopathies, which include Alzheimer’s disease. Furthermore, building upon our ability to engineer Nbs for the compartment-specific cellular delivery, we plan to modulate nuclear Tau function. These cell-permeable Tau-specific Nbs will be chemically modified to monitor their location in cells, thus providing new tools for biological and biomedical research. NanoTarget’s ultimate goal is to provide unprecedented Tau-specific nanobody-based modalities with unmet potential as biological research tools and next-generation biopharmaceuticals. NanoTarget will support our research in the highly competitive field of tauopathies but also extend our original advances in the field of cancer. To date, the potential to reach Tau inside the cells with immunologic approaches has hardly been investigated. The intracellular delivery of functional proteins in living cells, which is essential for NanoTarget, is indeed a challenging task in the molecular life sciences, but it could prove extremely powerful for the development of new drugs. Key factors to be addressed in this context include the stability, cell permeability, and pharmacologic potency of the delivered proteins while maintaining their functional properties. The project’s viability to reach this ambitious goal is supported by the applicants’ proven expertise in protein chemistry and in particular cell-permeable Nb engineering, structural biology, cell biology, their solid track record in Tau research, and their previous successful collaborations.