Nanopipette-assisted single cell metabolic glycan labeling

Yang

Guan

2020

Cells

112

Sialic acids, a subset of nine carbon acidic sugars, often exist as the terminal sugars of glycans on either glycoproteins or glycolipids on the cell surface. Sialic acids play important roles in many physiological and pathological processes via carbohydrate-protein interactions, including cell–cell communication, bacterial and viral infections. In particular, hypersialylation in tumors, as well as their roles in tumor growth and metastasis, have been widely described. Recent studies have indicated that the aberrant sialylation is a vital way for tumor cells to escape immune surveillance and keep malignance. In this article, we outline the present state of knowledge on the metabolic pathway of human sialic acids, the function of hypersialylation in tumors, as well as the recent labeling and analytical techniques for sialic acids. It is expected to offer a brief introduction of sialic acid metabolism and provide advanced analytical strategies in sialic acid studies.

Section: Sialic Acids Metabolic Glycan Labelingmentioning

confidence: 99%

Biological Functions and Analytical Strategies of Sialic Acids in Tumor

Yang

Guan

2020

Cells

112

“…In addition, NanoNiche successfully stripped SA on MDA-MB-231 cells after attachment to the plasma membrane. MDA-MB-231 cells were pretreated with an unnatural azide-tagged mannose (ManNAz, expressing azide-tagged sialic acid on the cell surface) and were then marked with fluorophores (alkyne-AF488) for metabolic SA labeling (Supporting Information, Figure S8). , As shown in Figure b, after incubation with NanoNiche, the fluorescence signal on the cell surface gradually decreased in less than 0.5 h, which confirmed SA degradation by NanoNiche.…”

Section: Results and Discussionmentioning

confidence: 85%

Sialidase-Conjugated “NanoNiche” for Efficient Immune Checkpoint Blockade Therapy

Wang

Jiang

et al. 2021

ACS Appl. Bio Mater.

Self Cite

Reactivation of T-cell immunity by blocking the PD-1/PD-L1 immune checkpoint has been considered a promising strategy for cancer treatment. However, the recognition of PD-L1 by antibodies is usually suppressed due to the N-linked glycosylation of PD-L1. In this study, we present an effective PD-L1-blocking strategy based on a sialidase-conjugated “NanoNiche” to improve the antitumor effect via T-cell reactivation. Molecularly imprinted by PD-L1 N-glycans, NanoNiche can specifically recognize glycosylated PD-L1 on the tumor cell surface, thereby resulting in more efficient PD-L1 blockade. Moreover, sialidase modified on the surface of NanoNiche can selectively strip sialoglycans from tumor cells, enhancing immune cell infiltration. In vitro studies confirmed that NanoNiche can specifically bind with PD-L1 while also desialylate the tumor cell surface. The proliferation of PD-L1-positive MDA-MB-231 human breast cancer cells under T-cell killing was significantly inhibited after NanoNiche treatment. In vivo experiments in solid tumors show enhanced therapeutic efficacy. Thus, the NanoNiche-sialidase conjugate represents a promising approach for immune checkpoint blockade therapy.

“…In 2019, Zhou reported the application of nanopipette to straightforwardly label glycans on single cell surface by metabolic labelling. [52] They shorten the metabolic labelling time from 24 h to 6 h. The tip hole of the nanopipette is around 100 nm and can inject azide-tagged artificial saccharide solution ManNAz into the cell without damage of cell morphology. And then use alkyne-AF488 in following click fluorescence labelling.…”

Section: Specific Modification Methodsmentioning

confidence: 99%

“…Zhou has successfully applied this method to achieve efficient transmembrane transport with electroosmotic flow. [52] With a constant voltage, there will be stable cyclic oscillations from continuous current versus time traces. The results show that the time domain of the current is composed of two frequencies.…”

Section: Single Cell Membrane Vibration Signalsmentioning

confidence: 99%

Recent Progress and Perspectives on Cell Surface Modification

Zhang

Chemistry An Asian Journal

Qian

2021

The cell membrane is a biological interface consisting of phospholipid bilayer, saccharides and proteins that maintains a stable metabolic intracellular environment as well as regulating and controlling the exchange of substances inside and outside the cell. Cell membranes provide a highly complex biological surface carrying a variety of essential surfaces ligands and receptors for cells to receive various stimuli of external signals, thereby inducing corresponding cell responses regulating the life activities of the cell. These surface receptors can be manipulated via cell surface modification to regulate cellular functions and behaviors Thus, cell surface modification has attracted considerable attention due to its significance in cell fate control, cell engineering and cell therapy. In this minireview, we describe the recent developments and advances of cell surface modification, and summarize the main modification methods with corresponding functions and applications. Finally, the prospect for the future development of the modification of the living cell membrane is discussed.