权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Reversible Phosphorothioate Backbone Modification for Oligonucleotide Delivery and Control

用于寡核苷酸递送和控制的可逆硫代磷酸酯主链修饰

基本信息

批准号：
2112306
负责人：
金额：
--
依托单位：
University of Oxford
依托单位国家：
英国
项目类别：
Studentship
财政年份：
2018
资助国家：
英国
起止时间：
2018 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=studentship-2112306
关键词：
Reversible Phosphorothioate Backbone Modification Oligonucleotide

项目摘要

Background:Oligonucleotide therapeutics show great promise to treat a variety of diseases on a genetic level. One major problem current oligonucleotide therapeutics face is poor delivery. Oligonucleotides are large, highly negatively charged biomolecules with poor bioavailability and ineffective cell delivery. Due to their highly anionic nature, these drugs poorly bind to plasma proteins, which reduces tissue distribution. Additionally, internalisation into cells is hindered, as they do not spontaneously cross cellular membranes. It is well known that modification of oligonucleotides is essential to improve their pharmacological properties, as first generation oligonucleotide therapeutics suffered from fast turnover and the inability to achieve sufficient intracellular concentrations. To improve stability and delivery of oligonucleotide therapeutics, a large number of modifications are employed, the most common of which is the phosphorothioate backbone. These modifications allow for better distribution, while still retaining the desired activity; however, tissue levels are still low and off-target effects are often observed.Project Summary:This project aims at exploiting the inherent reactivity of the phosphorothioate for chemical modification with stimuli-responsive chemical groups. These groups can then be selectively removed by application of the stimulus, allowing for spatial and temporal control of oligonucleotide release. It is believed that through the masking of the charge and the increase in lipophilicity with chemical modification, the pharmacological properties of distribution and cell penetration should be improved. Additionally, through the stimuli-responsive regeneration of the unmodified oligonucleotide, off-target effects will be reduced.It has been shown that the phosphorothioate is reactive towards chemical groups and that modification increases its lipophilicity. However, there are no accounts yet on the reversible masking of phosphorothioates and their applications in living systems. To study this, a variety of reactive stimuli-responsive chemical groups will be synthesised and their reactivity towards phosphorothioates studied. Following evaluation of the chemistry of these modifications, known therapeutic sequences will be modified as above and their delivery into living cells and their biological activity will be investigated. These biological studies will aid in the design of further modifications. These modified oligonucleotides will then be used on cellular disease models to measure their efficacy against current oligonucleotide therapies.This project is undertaken in the group of Dr. Michael Booth within the Synthesis for Biology and Medicine Centre for Doctoral Training (SBM CDT) at the University of Oxford. The project falls within the EPSRC chemical biology and biological chemistry research area.

背景：寡核苷酸疗法在基因水平上治疗各种疾病方面显示出巨大的前景。当前寡核苷酸治疗面临的一个主要问题是递送不良。寡核苷酸是大的、高度带负电荷的生物分子，具有差的生物利用度和无效的细胞递送。由于它们的高度阴离子性质，这些药物与血浆蛋白的结合很差，这减少了组织分布。此外，由于它们不能自发地穿过细胞膜，因此进入细胞的内化受到阻碍。众所周知，寡核苷酸的修饰对于改善其药理学性质是必不可少的，因为第一代寡核苷酸治疗剂遭受快速转换和不能实现足够的细胞内浓度。为了改善寡核苷酸治疗剂的稳定性和递送，采用了大量修饰，其中最常见的是硫代磷酸酯骨架。这些修饰允许更好的分布，同时仍然保留所需的活性;然而，组织水平仍然很低，并且经常观察到脱靶效应。项目概述：本项目旨在利用硫代磷酸酯的固有反应性，用刺激响应化学基团进行化学修饰。然后，这些基团可以通过施加刺激选择性地去除，从而允许寡核苷酸释放的空间和时间控制。据信，通过化学修饰掩蔽电荷和增加亲脂性，应改善分布和细胞渗透的药理学性质。此外，通过未修饰的寡核苷酸的刺激响应性再生，脱靶效应将减少。已经表明，硫代磷酸酯对化学基团具有反应性，并且修饰增加了其亲脂性。然而，还没有关于硫代磷酸酯的可逆掩蔽及其在生命系统中的应用的报道。为了研究这一点，将合成各种反应性刺激响应化学基团，并研究它们对硫代磷酸酯的反应性。在评价这些修饰的化学性质后，将如上所述修饰已知的治疗序列，并研究它们向活细胞中的递送及其生物活性。这些生物学研究将有助于进一步修改的设计。这些修饰的寡核苷酸将用于细胞疾病模型，以测量其对当前寡核苷酸疗法的疗效。该项目由牛津大学生物学和医学博士培训合成中心（SBM CDT）的Michael Booth博士团队进行。该项目属于EPSRC化学生物学和生物化学研究领域的福尔斯。