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Chemoenzymatic glycan editing for deciphering biological functions of glycans

化学酶聚糖编辑破译聚糖的生物学功能

基本信息

批准号：
10799053
负责人：
Peng Wu
金额：
$ 14.61万
依托单位：
SCRIPPS RESEARCH INSTITUTE, THE
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-02-01 至 2026-01-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10799053
关键词：
Affinity Autoimmune Diseases Binding Binding Proteins Biological Process Cell Communication Cell physiology Cell surface Cells Development Disease Progression Engineering Environment FDA approved Fucose Genome Glycoconjugates Glycoproteins Goals Immune Immune System Diseases Immune checkpoint inhibitor Immune signaling Immunoglobulins Immunotherapy In Situ Label Lectin Ligands Malignant Neoplasms Mediating Metabolic Methods Modality Modification Molecular Molecular Biology Techniques Monosaccharides N-acetyllactosamine Natural Killer Cells Oligosaccharides Organism Patients Polysaccharides Production Proliferating Property Recombinants Role Sialic Acids Signal Transduction Specificity Structure T-Lymphocyte Therapeutic Agents Tumor Immunity Vaccination Visualization anti-CTLA4 anti-PD-1 checkpoint inhibition cytokine cytotoxic exhaustion glycosylation glycosyltransferase human disease immune activation immunoregulation interest novel novel therapeutics receptor receptor binding response sialic acid binding Ig-like lectin sialylation sugar nucleotide tool

项目摘要

PROJECT SUMMARY/ABSTRACT Cell-surface glycans participate in numerous biological processes, including signal transduction, cell-cell communication and development. Aberrant glycosylation is a hallmark of human disease. At a molecular level, glycans represent the first points of contact between cells. However, not directly encoded in the genome, these biomolecules are challenging to study using molecular biology techniques alone. Metabolic oligosaccharide engineering (MOE) developed in late 1990’s has revolutionized the way for the labeling and visualization of glycans in living organisms. In this method, cells’ own glycan biosynthetic machinery is hijacked to incorporate unnatural monosaccharides with linkage promiscuity. Complementary to MOE, chemoenzymatic glycan editing has emerged as a valuable tool to probe and modify glycan structures within a cellular environment. Unlike MOE, chemoenzymatic glycan modification utilizes recombinant glycosyltransferases to transfer natural or unnatural monosaccharides with novel functions from activated nucleotide sugars to glycoconjugates on the cell surface with linkage specificity. For these reasons, chemoenzymatic glycan modification provides a facile and more precise way for probing the function of glycans in their native environments. Building upon our successful application of chemoenzymatic glycan editing, in the next five years we will expand our chemoenzymatic tool kits to study glycans’ cellular functions with a focus on the special roles of N- acetyllactosamine (LacNAc), fucose and sialic acid in immune regulation. Cell-surface LacNAc mediates ligand-receptor binding and sets a threshold for initiating the downstream signaling for immune cell activation. LacNAc residues are dynamically modified by sialic acid and/or fucose. However, the specific roles of these modifications in immune regulation and disease progression remain obscure. We are particularly interested in finding out: (1) if changes in LacNAc and fucosylation status can serve as glycan signatures of T cell exhaustion during which T cells gradually lose their cytokine production, proliferation and cytotoxic capacity; (2) Can cell-surface in situ LacNAc fucosylation be used to boost the efficacy of antitumor immunity of T cells and NK cells? In parallel, we will develop chemoenzymatic tools for profiling sialylated glycoprotein ligands of Siglecs (sialic acid-binding immunoglobulin-type lectins) and for the identification of unnatural, high-affinity and specific ligands to interrogate Siglec functions. Through these studies, we will gain a deeper understanding of how LacNAc, fucose and sialic acid are involved in the regulation of the immune cell activation, effector function and exhaustion. Tools developed in this project can also be used to study other types of glycans and their interactions with glycan binding proteins.

项目摘要/摘要细胞-表面糖链参与多种生物过程，包括信号转导、细胞-细胞交流与发展。糖基化异常是人类疾病的一个标志。在分子水平上，多聚糖代表细胞之间的第一个接触点。然而，这些并不是直接在基因组中编码的仅用分子生物学技术来研究生物分子是具有挑战性的。代谢性低聚糖 20世纪90年代末发展起来的工程学(MoE)，S彻底改变了对生物的标记和可视化的方式生物体内的多聚糖。在这种方法中，细胞自身的葡聚糖生物合成机制被劫持以整合具有连锁混杂的非天然单糖。作为MOE的补充，化学酶多糖编辑已成为一种有价值的工具在细胞环境中修饰多糖结构。与MOE不同的是，化学酶促多聚糖修饰利用重组糖基转移酶转移具有新功能的天然或非天然单糖从激活的核苷酸糖到细胞表面的具有连接特异性的糖偶联物。为了这些因此，化学酶修饰多糖为探索其功能提供了一种简便、准确的方法。在它们的原生环境中发现了大量的多糖。在我们成功应用化学酶多聚糖编辑的基础上，我们将在未来五年内扩展我们的化学酶工具包来研究多糖的细胞功能，重点是N-的特殊作用乙酰乳糖胺(LacNAc)、岩藻糖和唾液酸在免疫调节中的作用细胞表面LacNAc介导配体-受体结合，并为启动免疫细胞激活的下游信号设定阈值。 LacNAc残基被唾液酸和/或岩藻糖动态修饰。然而，这些人的具体作用免疫调节和疾病进展方面的修改仍然不清楚。我们特别感兴趣的是：(1)LacNAc和岩藻糖化状态的变化是否可以作为T细胞耗尽期间T细胞逐渐失去细胞因子的糖链信号， (2)细胞表面原位LacNAc岩藻糖基化能否促进细胞增殖 T细胞和NK细胞的抗肿瘤免疫效果？同时，我们将开发化学酶工具用于 Siglecs唾液酸化糖蛋白配体(唾液酸结合免疫球蛋白类型凝集素)的分析鉴定非自然的、高亲和力的和特定的配体以询问Siglec的功能。通过这些研究，我们将对LacNAc、岩藻糖和唾液酸是如何参与调节免疫细胞的激活、效应功能和力竭。开发的工具该项目还可用于研究其他类型的多糖及其与多糖结合蛋白的相互作用。