1
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Tay HM, Docker A, Taylor AJ, Beer PD. A Halogen Bonding [2]Rotaxane Shuttle for Chloride-Selective Optical Sensing. Chemistry 2024:e202400952. [PMID: 38536767 DOI: 10.1002/chem.202400952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Indexed: 04/25/2024]
Abstract
The first example of a [2]rotaxane shuttle capable of selective optical sensing of chloride anions over other halides is reported. The rotaxane was synthesised via a chloride ion template-directed cyclisation of an isophthalamide macrocycle around a multi-station axle containing peripheral naphthalene diimide (NDI) stations and a halogen bonding (XB) bis(iodotriazole) based station. Proton NMR studies indicate the macrocycle resides preferentially at the NDI stations in the free rotaxane, where it is stabilised by aromatic donor-acceptor charge transfer interactions between the axle NDI and macrocycle hydroquinone moieties. Addition of chloride ions in an aqueous-acetone solvent mixture induces macrocycle translocation to the XB anion binding station to facilitate the formation of convergent XB⋅⋅⋅Cl- and hydrogen bonding HB⋅⋅⋅Cl- interactions, which is accompanied by a reduction of the charge-transfer absorption band. Importantly, little to no optical response was induced by addition of bromide or iodide to the rotaxane, indicative of the size discriminative steric inaccessibility of the interlocked cavity to the larger halides, demonstrating the potential of using the mechanical bond effect as a potent strategy and tool in chloride-selective chemo-sensing applications in aqueous containing solvent environments.
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Affiliation(s)
- Hui Min Tay
- Department of Chemistry, University of Oxford Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, United Kingdom
| | - Andrew Docker
- Department of Chemistry, University of Oxford Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, United Kingdom
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United Kingdom
| | - Andrew J Taylor
- Department of Chemistry, University of Oxford Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, United Kingdom
| | - Paul D Beer
- Department of Chemistry, University of Oxford Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, United Kingdom
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2
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Leong SY, Lok WW, Goh KY, Ong HB, Tay HM, Su C, Kong F, Upadya M, Wang W, Radnaa E, Menon R, Dao M, Dalan R, Suresh S, Lim DWT, Hou HW. High-Throughput Microfluidic Extraction of Platelet-free Plasma for MicroRNA and Extracellular Vesicle Analysis. ACS Nano 2024; 18:6623-6637. [PMID: 38348825 DOI: 10.1021/acsnano.3c12862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
Abstract
Cell-free RNAs and extracellular vesicles (EVs) are valuable biomarkers in liquid biopsies, but they are prone to preanalytical variabilities such as nonstandardized centrifugation or ex vivo blood degradation. Herein, we report a high-throughput and label-free inertial microfluidic device (ExoArc) for isolation of platelet-free plasma from blood for RNA and EV analysis. Unlike conventional inertial microfluidic devices widely used for cell sorting, a submicrometer size cutoff (500 nm) was achieved which completely removed all leukocytes, RBCs, platelets, and cellular debris based on differential lateral migration induced by Dean vortices. The single-step operation also reduced platelet-associated miRNAs (∼2-fold) compared to centrifugation. We clinically validated ExoArc for plasma miRNA profiling (39 samples) and identified a 7-miRNA panel that detects non-small cell lung cancer with ∼90% sensitivity. ExoArc was also coupled with size exclusion chromatography (SEC) to isolate EVs within 50 min with ∼10-fold higher yield than ultracentrifugation. As a proof-of-concept for EV-based transcriptomics analysis, we performed miRNA analysis in healthy and type 2 diabetes mellitus (T2DM) subjects (n = 3 per group) by coupling ExoArc and ExoArc+SEC with quantitative polymerase chain reaction (RT-qPCR) assay. Among 293 miRNAs detected, plasmas and EVs showed distinct differentially expressed miRNAs in T2DM subjects. We further demonstrated automated in-line EV sorting from low volume culture media for continuous EV monitoring. Overall, the developed ExoArc offers a convenient centrifugation-free workflow to automate plasma and EV isolation for point-of-care diagnostics and quality control in EV manufacturing.
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Affiliation(s)
- Sheng Yuan Leong
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798
| | - Wan Wei Lok
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798
| | - Kah Yee Goh
- Division of Medical Oncology, National Cancer Centre Singapore, Singapore 168583
| | - Hong Boon Ong
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798
| | - Hui Min Tay
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798
| | - Chengxun Su
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798
| | - Fang Kong
- School of Biological Sciences, Nanyang Technological University, Singapore 637551
| | - Megha Upadya
- School of Biological Sciences, Nanyang Technological University, Singapore 637551
| | - Wei Wang
- Singapore Institute of Manufacturing Technology (SIMTech), Agency for Science, Technology and Research (A*STAR), Singapore 138634
| | - Enkhtuya Radnaa
- Department of Obstetrics and Gynecology, The University of Texas Medical Branch at Galveston, Galveston, Texas 77555-1062, United States
| | - Ramkumar Menon
- Department of Obstetrics and Gynecology, The University of Texas Medical Branch at Galveston, Galveston, Texas 77555-1062, United States
| | - Ming Dao
- School of Biological Sciences, Nanyang Technological University, Singapore 637551
- Department of Material Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Rinkoo Dalan
- Endocrine and Diabetes, Tan Tock Seng Hospital, Singapore 308433
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 308232
| | - Subra Suresh
- Department of Material Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- School of Material Science and Engineering, Nanyang Technological University, Singapore 639798
| | - Darren Wan-Teck Lim
- Division of Medical Oncology, National Cancer Centre Singapore, Singapore 168583
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), Singapore 138673
- Duke-NUS Medical School, Singapore 169857
| | - Han Wei Hou
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 308232
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3
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Min Tay H, Johnson TG, Docker A, Langton MJ, Beer PD. Exploiting the Catenane Mechanical Bond Effect for Selective Halide Anion Transmembrane Transport. Angew Chem Int Ed Engl 2023; 62:e202312745. [PMID: 37772928 DOI: 10.1002/anie.202312745] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 09/26/2023] [Accepted: 09/28/2023] [Indexed: 09/30/2023]
Abstract
The first examples of [2]catenanes capable of selective anion transport across a lipid bilayer are reported. The neutral halogen bonding (XB) [2]catenanes were prepared via a chloride template-directed strategy in an unprecedented demonstration of using XB⋅⋅⋅anion interactions to direct catenane assembly from all-neutral components. Anion binding experiments in aqueous-organic solvent media revealed strong halide over oxoanion selectivity, and a marked enhancement in the chloride and bromide affinities of the catenanes relative to their constituent macrocycles. The catenanes additionally displayed an anti-Hofmeister binding preference for bromide over the larger iodide anion, illustrating the efficacy of employing sigma-hole interactions in conjunction with the mechanical bond effect to tune receptor selectivity. Transmembrane anion transport studies conducted in POPC LUVs revealed that the catenanes were more effective anion transporters than the constituent macrocycles, with high chloride over hydroxide selectivity, which is critical to potential therapeutic applications of anionophores. Remarkably these outperform existing acyclic halogen bonding anionophores with regards to this selectivity. Record chloride over nitrate anion transport selectivity was also observed. This represents a rare example of the direct translation of intrinsic anion binding affinities to anion transport behaviour, and demonstrates the key role of the catenane mechanical bond effect for enhanced anion transport selectivity.
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Affiliation(s)
- Hui Min Tay
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, United Kingdom
| | - Toby G Johnson
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, United Kingdom
| | - Andrew Docker
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, United Kingdom
| | - Matthew J Langton
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, United Kingdom
| | - Paul D Beer
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, United Kingdom
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4
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Arun A, Docker A, Min Tay H, Beer PD. Squaramide-Based Heteroditopic [2]Rotaxanes for Sodium Halide Ion-Pair Recognition. Chemistry 2023; 29:e202301446. [PMID: 37300836 PMCID: PMC10946609 DOI: 10.1002/chem.202301446] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 06/07/2023] [Accepted: 06/09/2023] [Indexed: 06/12/2023]
Abstract
A series of squaramide-based heteroditopic [2]rotaxanes consisting of isophthalamide macrocycle and squaramide axle components are synthesized using an alkali metal cation template-directed stoppering methodology. This work highlights the unprecedented sodium cation template coordination of the Lewis basic squaramide carbonyls for interlocked structure synthesis. Extensive quantitative 1 H NMR spectroscopic anion and ion-pair recognition studies reveal the [2]rotaxane hosts are capable of cooperative sodium halide ion-pair mechanical bond axle-macrocycle component recognition, eliciting up to 20-fold enhancements in binding strengths for bromide and iodide, wherein the Lewis basic carbonyls and Lewis acidic NH hydrogen bond donors of the squaramide axle motif operate as cation and anion receptive sites simultaneously in an ambidentate fashion. Notably, varying the length and nature of the polyether cation binding unit of the macrocycle component dramatically influences the ion-pair binding affinities of the [2]rotaxanes, even overcoming direct contact NaCl ion-pair binding modes in polar organic solvents. Furthermore, the cooperative ion-pair binding properties of the squaramide-based heteroditopic [2]rotaxanes are exploited to successfully extract solid sodium halide salts into organic media.
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Affiliation(s)
- Arya Arun
- Department of ChemistryUniversity of OxfordChemistry Research LaboratoryMansfield RoadOX1 3TAOxfordUK
| | - Andrew Docker
- Department of ChemistryUniversity of OxfordChemistry Research LaboratoryMansfield RoadOX1 3TAOxfordUK
| | - Hui Min Tay
- Department of ChemistryUniversity of OxfordChemistry Research LaboratoryMansfield RoadOX1 3TAOxfordUK
| | - Paul D. Beer
- Department of ChemistryUniversity of OxfordChemistry Research LaboratoryMansfield RoadOX1 3TAOxfordUK
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Petchakup C, Chen YYC, Tay HM, Ong HB, Hon PY, De PP, Yeo TW, Li KHH, Vasoo S, Hou HW. Rapid Screening of Urinary Tract Infection Using Microfluidic Inertial-Impedance Cytometry. ACS Sens 2023; 8:3136-3145. [PMID: 37477562 DOI: 10.1021/acssensors.3c00819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/22/2023]
Abstract
Urinary tract infection (UTI) diagnosis based on urine culture for bacteriuria analysis is time-consuming and often leads to wastage of hospital resources due to false-positive UTI cases. Direct cellular phenotyping (e.g., RBCs, neutrophils, epithelial cells) of urine samples remains a technical challenge as low cell concentrations, and urine characteristics (conductivities, pH, microbes) can affect the accuracy of cell measurements. In this work, we report a microfluidic inertial-impedance cytometry technique for label-free rapid (<5 min) neutrophil sorting and impedance profiling from urine directly. Based on size-based inertial focusing effects, neutrophils are isolated, concentrated, and resuspended in saline (buffer exchange) to improve consistency in impedance-based single-cell analysis. We first observed that both urine pH and the presence of bacteria can affect neutrophil high-frequency impedance measurements possibly due to changes in nucleus morphology as neutrophils undergo NETosis and phagocytosis, respectively. As a proof-of-concept for clinical testing, we report for the first time, rapid UTI testing based on multiparametric impedance profiling of putative neutrophils (electrical size, membrane properties, and distribution) in urine samples from non-UTI (n = 20) and UTI patients (n = 20). A significant increase in cell count was observed in UTI samples, and biophysical parameters were used to develop a UTI classifier with an area under the receiver operating characteristic curve of 0.84. Overall, the developed platform facilitates rapid culture-free urine screening which can be further developed to assess disease severity in UTI and other urologic diseases based on neutrophil electrical signatures.
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Affiliation(s)
- Chayakorn Petchakup
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798, Singapore
| | | | - Hui Min Tay
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798, Singapore
| | - Hong Boon Ong
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798, Singapore
| | - Pei Yun Hon
- National Center for Infectious Disease, Tan Tock Seng Hospital, Singapore 308442, Singapore
| | - Partha Pratim De
- Department of Laboratory Medicine, Tan Tock Seng Hospital, Singapore 308433, Singapore
| | - Tsin Wen Yeo
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 308232, Singapore
| | - King Ho Holden Li
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798, Singapore
| | - Shawn Vasoo
- National Center for Infectious Disease, Tan Tock Seng Hospital, Singapore 308442, Singapore
| | - Han Wei Hou
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 308232, Singapore
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6
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Tay HM, Docker A, Tse YC, Beer PD. Alkali Metal Halide Ion-Pair Binding in Conformationally Dynamic Halogen Bonding Heteroditopic [2]Rotaxanes. Chemistry 2023:e202301316. [PMID: 37199337 DOI: 10.1002/chem.202301316] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 05/16/2023] [Accepted: 05/17/2023] [Indexed: 05/19/2023]
Abstract
A series of heteroditopic halogen bonding (XB) [2]rotaxanes were prepared via a combination of passive and active metal template-directed strategies. The ability of the [2]rotaxanes to bind alkali metal halide ion-pairs was investigated by extensive 1H NMR titration studies, wherein detailed analysis of cation, anion and ion-pair affinity measurements indicate dramatic positive cooperative enhancements in halide anion association upon either Na+ or K+ pre-complexation. We demonstrate that careful consideration of multiple, parallel and competing binding equilibria is essential when interpreting observed 1H NMR spectral changes in ion-pair receptor systems, especially those which exhibit dynamic behaviour. Importantly, in comparison to XB [2]catenane analogues, these neutral XB heteroditopic [2]rotaxane host systems demonstrated that despite their relatively weaker cation and anion binding abilities, they exhibit a notably higher level of positive cooperativity for alkali metal halide ion-pair binding, highlighting the role of greater co-conformational adaptive behaviour in mechanically-bonded hosts for the purposes of charged species recognition.
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Affiliation(s)
- Hui Min Tay
- University of Oxford, Inorganic Chemistry, UNITED KINGDOM
| | - Andrew Docker
- University of Oxford, Inorganic Chemistry, UNITED KINGDOM
| | | | - Paul D Beer
- University of Oxford, Inorganic Chemistry Laboratory, South Parks Road, OX1 3QR, Oxford, UNITED KINGDOM
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7
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Lu N, Tay HM, Petchakup C, He L, Gong L, Maw KK, Leong SY, Lok WW, Ong HB, Guo R, Li KHH, Hou HW. Label-free microfluidic cell sorting and detection for rapid blood analysis. Lab Chip 2023; 23:1226-1257. [PMID: 36655549 DOI: 10.1039/d2lc00904h] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Blood tests are considered as standard clinical procedures to screen for markers of diseases and health conditions. However, the complex cellular background (>99.9% RBCs) and biomolecular composition often pose significant technical challenges for accurate blood analysis. An emerging approach for point-of-care blood diagnostics is utilizing "label-free" microfluidic technologies that rely on intrinsic cell properties for blood fractionation and disease detection without any antibody binding. A growing body of clinical evidence has also reported that cellular dysfunction and their biophysical phenotypes are complementary to standard hematoanalyzer analysis (complete blood count) and can provide a more comprehensive health profiling. In this review, we will summarize recent advances in microfluidic label-free separation of different blood cell components including circulating tumor cells, leukocytes, platelets and nanoscale extracellular vesicles. Label-free single cell analysis of intrinsic cell morphology, spectrochemical properties, dielectric parameters and biophysical characteristics as novel blood-based biomarkers will also be presented. Next, we will highlight research efforts that combine label-free microfluidics with machine learning approaches to enhance detection sensitivity and specificity in clinical studies, as well as innovative microfluidic solutions which are capable of fully integrated and label-free blood cell sorting and analysis. Lastly, we will envisage the current challenges and future outlook of label-free microfluidics platforms for high throughput multi-dimensional blood cell analysis to identify non-traditional circulating biomarkers for clinical diagnostics.
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Affiliation(s)
- Nan Lu
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Blk N3, Level 2, Room 86 (N3-02c-86), 639798, Singapore.
- HP-NTU Digital Manufacturing Corporate Lab, Nanyang Technological University, 65 Nanyang Drive, Block N3, 637460, Singapore
| | - Hui Min Tay
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Blk N3, Level 2, Room 86 (N3-02c-86), 639798, Singapore.
| | - Chayakorn Petchakup
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Blk N3, Level 2, Room 86 (N3-02c-86), 639798, Singapore.
| | - Linwei He
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Blk N3, Level 2, Room 86 (N3-02c-86), 639798, Singapore.
| | - Lingyan Gong
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Blk N3, Level 2, Room 86 (N3-02c-86), 639798, Singapore.
| | - Kay Khine Maw
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Blk N3, Level 2, Room 86 (N3-02c-86), 639798, Singapore.
| | - Sheng Yuan Leong
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Blk N3, Level 2, Room 86 (N3-02c-86), 639798, Singapore.
| | - Wan Wei Lok
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Blk N3, Level 2, Room 86 (N3-02c-86), 639798, Singapore.
| | - Hong Boon Ong
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Blk N3, Level 2, Room 86 (N3-02c-86), 639798, Singapore.
| | - Ruya Guo
- Key Laboratory of Agricultural Information Acquisition Technology, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100083, China
| | - King Ho Holden Li
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Blk N3, Level 2, Room 86 (N3-02c-86), 639798, Singapore.
- HP-NTU Digital Manufacturing Corporate Lab, Nanyang Technological University, 65 Nanyang Drive, Block N3, 637460, Singapore
| | - Han Wei Hou
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Blk N3, Level 2, Room 86 (N3-02c-86), 639798, Singapore.
- HP-NTU Digital Manufacturing Corporate Lab, Nanyang Technological University, 65 Nanyang Drive, Block N3, 637460, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, 11 Mandalay Road, Clinical Sciences Building, 308232, Singapore
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8
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Deng Y, Tay HM, Zhou Y, Fei X, Tang X, Nishikawa M, Yatomi Y, Hou HW, Xiao TH, Goda K. Studying the efficacy of antiplatelet drugs on atherosclerosis by optofluidic imaging on a chip. Lab Chip 2023; 23:410-420. [PMID: 36511820 DOI: 10.1039/d2lc00895e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Vascular stenosis caused by atherosclerosis instigates activation and aggregation of platelets, eventually resulting in thrombus formation. Although antiplatelet drugs are commonly used to inhibit platelet activation and aggregation, they unfortunately cannot prevent recurrent thrombotic events in patients with atherosclerosis. This is partially due to the limited understanding of the efficacy of antiplatelet drugs in the complex hemodynamic environment of vascular stenosis. Conventional methods for evaluating the efficacy of antiplatelet drugs under stenosis either fail to simulate the hemodynamic environment of vascular stenosis characterized by high shear stress and recirculatory flow or lack spatial resolution in their analytical techniques to statistically identify and characterize platelet aggregates. Here we propose and experimentally demonstrate a method comprising an in vitro 3D stenosis microfluidic chip and an optical time-stretch quantitative phase imaging system for studying the efficacy of antiplatelet drugs under stenosis. Our method simulates the atherogenic flow environment of vascular stenosis while enabling high-resolution and statistical analysis of platelet aggregates. Using our method, we distinguished the efficacy of three antiplatelet drugs, acetylsalicylic acid (ASA), cangrelor, and eptifibatide, for inhibiting platelet aggregation induced by stenosis. Specifically, ASA failed to inhibit stenosis-induced platelet aggregation, while eptifibatide and cangrelor showed high and moderate efficacy, respectively. Furthermore, we demonstrated that the drugs tested also differed in their efficacy for inhibiting platelet aggregation synergistically induced by stenosis and agonists (e.g., adenosine diphosphate, and collagen). Taken together, our method is an effective tool for investigating the efficacy of antiplatelet drugs under vascular stenosis, which could assist the development of optimal pharmacologic strategies for patients with atherosclerosis.
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Affiliation(s)
- Yunjie Deng
- Department of Chemistry, University of Tokyo, Tokyo, 113-0033, Japan.
| | - Hui Min Tay
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Yuqi Zhou
- Department of Chemistry, University of Tokyo, Tokyo, 113-0033, Japan.
| | - Xueer Fei
- Department of Chemistry, University of Tokyo, Tokyo, 113-0033, Japan.
| | - Xuke Tang
- Department of Chemistry, University of Tokyo, Tokyo, 113-0033, Japan.
| | - Masako Nishikawa
- Department of Clinical Laboratory Medicine, Graduate School of Medicine, University of Tokyo, Tokyo, 113-0033, Japan
| | - Yutaka Yatomi
- Department of Clinical Laboratory Medicine, Graduate School of Medicine, University of Tokyo, Tokyo, 113-0033, Japan
| | - Han Wei Hou
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, 639798, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore
| | - Ting-Hui Xiao
- Department of Chemistry, University of Tokyo, Tokyo, 113-0033, Japan.
| | - Keisuke Goda
- Department of Chemistry, University of Tokyo, Tokyo, 113-0033, Japan.
- Institute of Technological Sciences, Wuhan University, Hubei, 430072, China
- Department of Bioengineering, University of California, Los Angeles, California, 90095, USA
- CYBO, Tokyo 101-0022, Japan
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9
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Tay HM, Tse YC, Docker A, Gateley C, Thompson AL, Kuhn H, Zhang Z, Beer PD. Halogen-Bonding Heteroditopic [2]Catenanes for Recognition of Alkali Metal/Halide Ion Pairs. Angew Chem Int Ed Engl 2023; 62:e202214785. [PMID: 36440816 PMCID: PMC10108176 DOI: 10.1002/anie.202214785] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 11/25/2022] [Accepted: 11/28/2022] [Indexed: 11/29/2022]
Abstract
The first examples of halogen bonding (XB) heteroditopic homo[2]catenanes were prepared by discrete Na+ template-directed assembly of oligo(ethylene glycol) units derived from XB donor-containing macrocycles and acyclic bis-azide precursors, followed by a CuI -mediated azide-alkyne cycloaddition macrocyclisation reaction. Extensive 1 H NMR spectroscopic studies show the [2]catenane hosts exhibit positive cooperative ion-pair recognition behaviour, wherein XB-mediated halide recognition is enhanced by alkali metal cation pre-complexation. Notably, subtle changes in the catenanes' oligo(ethylene glycol) chain length dramatically alters their ion-binding affinity, stoichiometry, complexation mode, and conformational dynamics. Solution-phase and single-crystal X-ray diffraction studies provide evidence for competing host-separated and direct-contact ion-pair binding modes. We further demonstrate the [2]catenanes are capable of extracting solid alkali-metal halide salts into organic media.
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Affiliation(s)
- Hui Min Tay
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, UK
| | - Yuen Cheong Tse
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, UK.,Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China
| | - Andrew Docker
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, UK
| | - Christian Gateley
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, UK
| | - Amber L Thompson
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, UK
| | - Heike Kuhn
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, UK
| | - Zongyao Zhang
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, UK
| | - Paul D Beer
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, UK
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10
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Tay HM, Tse YC, Docker A, Gateley C, Thompson AL, Kuhn H, Zhang Z, Beer PD. Halogen Bonding Heteroditopic [2]Catenanes for Recognition of Alkali Metal/Halide Ion Pairs. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202214785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hui Min Tay
- University of Oxford Inorganic Chemistry UNITED KINGDOM
| | | | - Andrew Docker
- University of Oxford Inorganic Chemistry UNITED KINGDOM
| | | | | | - Heike Kuhn
- University of Oxford Inorganic Chemistry UNITED KINGDOM
| | - Zongyao Zhang
- University of Oxford Inorganic Chemistry UNITED KINGDOM
| | - Paul D. Beer
- University of Oxford Inorganic Chemistry Laboratory South Parks Road OX1 3QR Oxford UNITED KINGDOM
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11
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Docker A, Tse YC, Tay HM, Taylor AJ, Zhang Z, Beer PD. Anti‐Hofmeister Anion Selectivity via a Mechanical Bond Effect in Neutral Halogen‐Bonding [2]Rotaxanes. Angew Chem Int Ed Engl 2022; 61:e202214523. [PMID: 36264711 PMCID: PMC10100147 DOI: 10.1002/anie.202214523] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Indexed: 11/18/2022]
Abstract
Exceptionally strong halogen bonding (XB) donor-chloride interactions are exploited for the chloride anion template synthesis of neutral XB [2]rotaxane host systems which contain perfluoroaryl-functionalised axle components, including a remarkably potent novel 4,6-dinitro-1,3-bis-iodotriazole motif. Halide anion recognition properties in aqueous-organic media, determined via extensive 1 H NMR halide anion titration experiments, reveal the rotaxane host systems exhibit dramatically enhanced affinities for hydrophilic Cl- and Br- , but conversely diminished affinities for hydrophobic I- , relative to their non-interlocked axle counterparts. Crucially, this mechanical bond effect induces a binding selectivity which directly opposes Hofmeister bias. Free-energy analysis of this mechanical bond enhancement demonstrates anion recognition by neutral XB interlocked host systems as a rare and general strategy to engineer anti-Hofmeister bias anion selectivity in synthetic receptor design.
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Affiliation(s)
- Andrew Docker
- Department of Chemistry University of Oxford Chemistry Research Laboratory 12 Mansfield Road Oxford OX1 3TA UK
| | - Yuen Cheong Tse
- Department of Chemistry University of Oxford Chemistry Research Laboratory 12 Mansfield Road Oxford OX1 3TA UK
| | - Hui Min Tay
- Department of Chemistry University of Oxford Chemistry Research Laboratory 12 Mansfield Road Oxford OX1 3TA UK
| | - Andrew J. Taylor
- Department of Chemistry University of Oxford Chemistry Research Laboratory 12 Mansfield Road Oxford OX1 3TA UK
| | - Zongyao Zhang
- Department of Chemistry University of Oxford Chemistry Research Laboratory 12 Mansfield Road Oxford OX1 3TA UK
| | - Paul D. Beer
- Department of Chemistry University of Oxford Chemistry Research Laboratory 12 Mansfield Road Oxford OX1 3TA UK
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12
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Docker A, Tse YC, Tay HM, Taylor AJ, Zhang Z, Beer PD. Anti‐Hofmeister Anion Selectivity via a Mechanical Bond Effect in Neutral Halogen‐Bonding [2]Rotaxanes. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202214523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Andrew Docker
- University of Oxford Department of Chemistry UNITED KINGDOM
| | | | - Hui Min Tay
- University of Oxford Department of Chemistry UNITED KINGDOM
| | | | - Zongyao Zhang
- University of Oxford Department of Chemistry UNITED KINGDOM
| | - Paul D. Beer
- University of Oxford Inorganic Chemistry Laboratory South Parks Road OX1 3QR Oxford UNITED KINGDOM
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13
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Petchakup C, Yang H, Gong L, He L, Tay HM, Dalan R, Chung AJ, Li KHH, Hou HW. Microfluidic Impedance-Deformability Cytometry for Label-Free Single Neutrophil Mechanophenotyping. Small 2022; 18:e2104822. [PMID: 35253966 DOI: 10.1002/smll.202104822] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 01/03/2022] [Indexed: 06/14/2023]
Abstract
The intrinsic biophysical states of neutrophils are associated with immune dysfunctions in diseases. While advanced image-based biophysical flow cytometers can probe cell deformability at high throughput, it is nontrivial to couple different sensing modalities (e.g., electrical) to measure other critical cell attributes including cell viability and membrane integrity. Herein, an "optics-free" impedance-deformability cytometer for multiparametric single cell mechanophenotyping is reported. The microfluidic platform integrates hydrodynamic cell pinching, and multifrequency impedance quantification of cell size, deformability, and membrane impedance (indicative of cell viability and activation). A newly-defined "electrical deformability index" is validated by numerical simulations, and shows strong correlations with the optical cell deformability index of HL-60 experimentally. Human neutrophils treated with various biochemical stimul are further profiled, and distinct differences in multimodal impedance signatures and UMAP analysis are observed. Overall, the integrated cytometer enables label-free cell profiling at throughput of >1000 cells min-1 without any antibodies labeling to facilitate clinical diagnostics.
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Affiliation(s)
- Chayakorn Petchakup
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Haoning Yang
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Lingyan Gong
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Linwei He
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Hui Min Tay
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Rinkoo Dalan
- Endocrinology Department, Tan Tock Seng Hospital, 11 Jln Tan Tock Seng Road, Singapore, 308433, Singapore
| | - Aram J Chung
- School of Biomedical Engineering, Korea University, Seoul, 02841, Republic of Korea
- Interdisciplinary Program in Precision Public Health, Korea University, Seoul, 02841, Republic of Korea
| | - King Ho Holden Li
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Han Wei Hou
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, 11 Mandalay Road, Clinical Sciences Building Level 11, Singapore, 308232, Singapore
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14
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Abstract
A fluorescent, chiral coordination polymer (CP) with a novel topology has been synthesised using a dipyridyl ligand derived from 1,1'-bi-2-naphthol (BINOL). Enantioselectivity ratios up to 2.61 were obtained in fluorescence sensing studies with chiral analytes.
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Affiliation(s)
- Shannon Thoonen
- School of Chemistry, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Hui Min Tay
- School of Chemistry, The University of Melbourne, Parkville, Victoria 3010, Australia.,Department of Chemistry, University of Oxford, Oxford OX1 3TA, UK
| | - Carol Hua
- School of Chemistry, The University of Melbourne, Parkville, Victoria 3010, Australia.,School of Life and Environmental Sciences, Deakin University, Waurn Ponds, Victoria 3216, Australia.
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15
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Tay HM, Hua C. A structural study into halogenated derivatives of mandelic acid as building blocks of chiral coordination polymers. J COORD CHEM 2022. [DOI: 10.1080/00958972.2022.2053958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Hui Min Tay
- School of Chemistry, The University of Melbourne, Parkville, Victoria, Australia
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, UK
| | - Carol Hua
- School of Chemistry, The University of Melbourne, Parkville, Victoria, Australia
- School of Life and Environmental Sciences, Deakin University, Waurn Ponds, Victoria, Australia
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16
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Wu KX, Yeo NJY, Ng CY, Chioh FWJ, Fan Q, Tian X, Yang B, Narayanan G, Tay HM, Hou HW, Dunn NR, Su X, Cheung CMG, Cheung C. Hyaluronidase-1-mediated glycocalyx impairment underlies endothelial abnormalities in polypoidal choroidal vasculopathy. BMC Biol 2022; 20:47. [PMID: 35164755 PMCID: PMC8845246 DOI: 10.1186/s12915-022-01244-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 02/01/2022] [Indexed: 11/11/2022] Open
Abstract
Background Polypoidal choroidal vasculopathy (PCV), a subtype of age-related macular degeneration (AMD), is a global leading cause of vision loss in older populations. Distinct from typical AMD, PCV is characterized by polyp-like dilatation of blood vessels and turbulent blood flow in the choroid of the eye. Gold standard anti-vascular endothelial growth factor (anti-VEGF) therapy often fails to regress polypoidal lesions in patients. Current animal models have also been hampered by their inability to recapitulate such vascular lesions. These underscore the need to identify VEGF-independent pathways in PCV pathogenesis. Results We cultivated blood outgrowth endothelial cells (BOECs) from PCV patients and normal controls to serve as our experimental disease models. When BOECs were exposed to heterogeneous flow, single-cell transcriptomic analysis revealed that PCV BOECs preferentially adopted migratory-angiogenic cell state, while normal BOECs undertook proinflammatory cell state. PCV BOECs also had a repressed protective response to flow stress by demonstrating lower mitochondrial functions. We uncovered that elevated hyaluronidase-1 in PCV BOECs led to increased degradation of hyaluronan, a major component of glycocalyx that interfaces between flow stress and vascular endothelium. Notably, knockdown of hyaluronidase-1 in PCV BOEC improved mechanosensitivity, as demonstrated by a significant 1.5-fold upregulation of Krüppel-like factor 2 (KLF2) expression, a flow-responsive transcription factor. Activation of KLF2 might in turn modulate PCV BOEC migration. Barrier permeability due to glycocalyx impairment in PCV BOECs was also reversed by hyaluronidase-1 knockdown. Correspondingly, hyaluronidase-1 was detected in PCV patient vitreous humor and plasma samples. Conclusions Hyaluronidase-1 inhibition could be a potential therapeutic modality in preserving glycocalyx integrity and endothelial stability in ocular diseases with vascular origin. Supplementary Information The online version contains supplementary material available at 10.1186/s12915-022-01244-z.
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Affiliation(s)
- Kan Xing Wu
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Natalie Jia Ying Yeo
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Chun Yi Ng
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | | | - Qiao Fan
- Duke-NUS Medical School, National University of Singapore, Singapore, Singapore.,Ophthalmology & Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore, Singapore
| | - Xianfeng Tian
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore.,Duke-NUS Medical School, National University of Singapore, Singapore, Singapore
| | - Binxia Yang
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Singapore, Singapore
| | - Gunaseelan Narayanan
- Institute of Medical Biology, Agency for Science, Technology and Research, Singapore, Singapore
| | - Hui Min Tay
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, Singapore
| | - Han Wei Hou
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore.,School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, Singapore
| | - N Ray Dunn
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore.,School of Biological Sciences Nanyang Technological University, Singapore, Singapore.,Institute of Medical Biology, Agency for Science Technology and Research, Singapore, Singapore
| | - Xinyi Su
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Singapore, Singapore.,Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Singapore Eye Research Institute, Singapore, Singapore.,Department of Ophthalmology, National University Hospital, Singapore, Singapore
| | - Chui Ming Gemmy Cheung
- Duke-NUS Medical School, National University of Singapore, Singapore, Singapore.,Singapore Eye Research Institute, Singapore, Singapore
| | - Christine Cheung
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore. .,Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Singapore, Singapore.
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17
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Leong SY, Ong HB, Tay HM, Kong F, Upadya M, Gong L, Dao M, Dalan R, Hou HW. Microfluidic Size Exclusion Chromatography (μSEC) for Extracellular Vesicles and Plasma Protein Separation. Small 2022; 18:e2104470. [PMID: 34984816 DOI: 10.1002/smll.202104470] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 12/02/2021] [Indexed: 05/04/2023]
Abstract
Extracellular vesicles (EVs) are recognized as next generation diagnostic biomarkers due to their disease-specific biomolecular cargoes and importance in cell-cell communications. A major bottleneck in EV sample preparation is the inefficient and laborious isolation of nanoscale EVs (≈50-200 nm) from endogenous proteins in biological samples. Herein, a unique microfluidic platform is reported for EV-protein fractionation based on the principle of size exclusion chromatography (SEC). Using a novel rapid (≈20 min) replica molding technique, a fritless microfluidic SEC device (μSEC) is fabricated using thiol-ene polymer (UV glue NOA81, Young's modulus ≈1 GPa) for high pressure (up to 6 bar) sample processing. Controlled on-chip nanoliter sample plug injection (600 nL) using a modified T-junction injector is first demonstrated with rapid flow switching response time (<1.5 s). Device performance is validated using fluorescent nanoparticles (50 nm), albumin, and breast cancer cells (MCF-7)-derived EVs. As a proof-of-concept for clinical applications, EVs are directly isolated from undiluted human platelet-poor plasma using μSEC and show distinct elution profiles between EVs and proteins based on nanoparticle particle analysis (NTA), Western blot and flow cytometry analysis. Overall, the optically transparent μSEC can be readily automated and integrated with EV detection assays for EVs manufacturing and clinical diagnostics.
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Affiliation(s)
- Sheng Yuan Leong
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Hong Boon Ong
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Hui Min Tay
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Fang Kong
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Singapore
| | - Megha Upadya
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Singapore
| | - Lingyan Gong
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Ming Dao
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Singapore
- Department of Material Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - Rinkoo Dalan
- Endocrine and Diabetes, Tan Tock Seng Hospital, 11 Jalan Tan Tock Seng, Singapore, 308433, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, 11 Mandalay Road, Clinical Sciences Building, Singapore, 308232, Singapore
| | - Han Wei Hou
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, 11 Mandalay Road, Clinical Sciences Building, Singapore, 308232, Singapore
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18
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Abstract
Three MOFs with metalloporphyrin lined, large square 1D channels were used as colorimetric sensors for electron donors. Exposure to amine vapours caused a redshift of the Soret absorption bands of the metalloporphyrin.
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Affiliation(s)
- Hui Min Tay
- School of Chemistry, The University of Melbourne, Parkville, Victoria, 3010, Australia
- Department of Chemistry, The University of Oxford, OX1 3TA, UK
| | - Emily J. Goddard
- School of Chemistry, The University of Melbourne, Parkville, Victoria, 3010, Australia
- Department of Chemistry, The University of Sheffield, S10 2TN, UK
| | - Carol Hua
- School of Chemistry, The University of Melbourne, Parkville, Victoria, 3010, Australia
- School of Life and Environmental Sciences, Deakin University, Waurn Ponds, Victoria, 3216, Australia
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19
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Foyle ÉM, Tay HM, White NG. Towards hydrogen and halogen bonded frameworks based on 3,5-bis(triazolyl)pyridinium motifs. CrystEngComm 2022. [DOI: 10.1039/d2ce00273f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Construction of supramolecular assemblies using hydrogen and halogen bonding between anions and the 3,5-bis(triazolyl)pyridinium motif was investigated.
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Affiliation(s)
- Émer M. Foyle
- Research School of Chemistry, The Australian National University, Canberra, ACT, Australia
| | - Hui Min Tay
- Research School of Chemistry, The Australian National University, Canberra, ACT, Australia
| | - Nicholas G. White
- Research School of Chemistry, The Australian National University, Canberra, ACT, Australia
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20
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Su C, Chuah YJ, Ong HB, Tay HM, Dalan R, Hou HW. A Facile and Scalable Hydrogel Patterning Method for Microfluidic 3D Cell Culture and Spheroid-in-Gel Culture Array. Biosensors (Basel) 2021; 11:bios11120509. [PMID: 34940266 PMCID: PMC8699815 DOI: 10.3390/bios11120509] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Revised: 12/06/2021] [Accepted: 12/07/2021] [Indexed: 05/14/2023]
Abstract
Incorporation of extracellular matrix (ECM) and hydrogel in microfluidic 3D cell culture platforms is important to create a physiological microenvironment for cell morphogenesis and to establish 3D co-culture models by hydrogel compartmentalization. Here, we describe a simple and scalable ECM patterning method for microfluidic cell cultures by achieving hydrogel confinement due to the geometrical expansion of channel heights (stepped height features) and capillary burst valve (CBV) effects. We first demonstrate a sequential "pillar-free" hydrogel patterning to form adjacent hydrogel lanes in enclosed microfluidic devices, which can be further multiplexed with one to two stepped height features. Next, we developed a novel "spheroid-in-gel" culture device that integrates (1) an on-chip hanging drop spheroid culture and (2) a single "press-on" hydrogel confinement step for rapid ECM patterning in an open-channel microarray format. The initial formation of breast cancer (MCF-7) spheroids was achieved by hanging a drop culture on a patterned polydimethylsiloxane (PDMS) substrate. Single spheroids were then directly encapsulated on-chip in individual hydrogel islands at the same positions, thus, eliminating any manual spheroid handling and transferring steps. As a proof-of-concept to perform a spheroid co-culture, endothelial cell layer (HUVEC) was formed surrounding the spheroid-containing ECM region for drug testing studies. Overall, this developed stepped height-based hydrogel patterning method is simple to use in either enclosed microchannels or open surfaces and can be readily adapted for in-gel cultures of larger 3D cellular spheroids or microtissues.
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Affiliation(s)
- Chengxun Su
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798, Singapore; (C.S.); (Y.J.C.); (H.B.O.); (H.M.T.)
- Interdisciplinary Graduate School, Nanyang Technological University, Singapore 639798, Singapore
| | - Yon Jin Chuah
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798, Singapore; (C.S.); (Y.J.C.); (H.B.O.); (H.M.T.)
| | - Hong Boon Ong
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798, Singapore; (C.S.); (Y.J.C.); (H.B.O.); (H.M.T.)
| | - Hui Min Tay
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798, Singapore; (C.S.); (Y.J.C.); (H.B.O.); (H.M.T.)
| | - Rinkoo Dalan
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 308232, Singapore;
- Endocrinology Department, Tan Tock Seng Hospital, Singapore 308433, Singapore
| | - Han Wei Hou
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798, Singapore; (C.S.); (Y.J.C.); (H.B.O.); (H.M.T.)
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 308232, Singapore;
- Correspondence:
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21
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Pang KT, Ghim M, Liu C, Tay HM, Fhu CW, Chia RN, Qiu B, Sarathchandra P, Chester AH, Yacoub MH, Wilkinson FL, Weston R, Warboys CM, Hou HW, Weinberg PD, Wang X. Leucine-Rich α-2-Glycoprotein 1 Suppresses Endothelial Cell Activation Through ADAM10-Mediated Shedding of TNF-α Receptor. Front Cell Dev Biol 2021; 9:706143. [PMID: 34291056 PMCID: PMC8288075 DOI: 10.3389/fcell.2021.706143] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 06/09/2021] [Indexed: 11/13/2022] Open
Abstract
Elevated serum concentrations of leucine-rich α-2-glycoprotein (LRG1) have been reported in patients with inflammatory, autoimmune, and cardiovascular diseases. This study aims to investigate the role of LRG1 in endothelial activation. LRG1 in endothelial cells (ECs) of arteries and serum of patients with critical limb ischemia (CLI) was assessed by immunohistochemistry and ELISA, respectively. LRG1 expression in sheared and tumor necrosis factor-α (TNF-α)-treated ECs was analyzed. The mechanistic role of LRG1 in endothelial activation was studied in vitro. Plasma of 37-week-old Lrg1 -/- mice was used to investigate causality between LRG1 and tumor necrosis factor receptor 1 (TNFR1) shedding. LRG1 was highly expressed in ECs of stenotic but not normal arteries. LRG1 concentrations in serum of patients with CLI were elevated compared to healthy controls. LRG1 expression was shear dependent. It could be induced by TNF-α, and the induction of its expression was mediated by NF-κB activation. LRG1 inhibited TNF-α-induced activation of NF-κB signaling, expression of VCAM-1 and ICAM-1, and monocyte capture, firm adhesion, and transendothelial migration. Mechanistically, LRG1 exerted its function by causing the shedding of TNFR1 via the ALK5-SMAD2 pathway and the subsequent activation of ADAM10. Consistent with this mechanism, LRG1 and sTNFR1 concentrations were correlated in the serum of CLI patients. Causality between LRG1 and TNFR1 shedding was established by showing that Lrg1 -/- mice had lower plasma sTNFR1 concentrations than wild type mice. Our results demonstrate a novel role for LRG1 in endothelial activation and its potential therapeutic role in inflammatory diseases should be investigated further.
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Affiliation(s)
- Kuin Tian Pang
- Department of Bioengineering, Imperial College London, London, United Kingdom.,Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A∗STAR), Singapore, Singapore
| | - Mean Ghim
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | - Chenghao Liu
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Hui Min Tay
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore.,School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, Singapore
| | - Chee Wai Fhu
- Cancer Science Institute of Singapore, National University of Singapore, Singapore
| | - Rui Ning Chia
- Centre for Vision Research, Duke-NUS Medical School, Singapore, Singapore
| | - Beiying Qiu
- Centre for Vision Research, Duke-NUS Medical School, Singapore, Singapore
| | - Padmini Sarathchandra
- Harefield Heart Science Centre, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Adrian H Chester
- Harefield Heart Science Centre, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Magdi H Yacoub
- Harefield Heart Science Centre, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Fiona L Wilkinson
- Department of Life Sciences, Manchester Metropolitan University, Manchester, United Kingdom
| | - Ria Weston
- Department of Life Sciences, Manchester Metropolitan University, Manchester, United Kingdom
| | - Christina M Warboys
- Comparative Biomedical Sciences, The Royal Veterinary College, London, United Kingdom
| | - Han Wei Hou
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore.,School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, Singapore
| | - Peter D Weinberg
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | - Xiaomeng Wang
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A∗STAR), Singapore, Singapore.,Centre for Vision Research, Duke-NUS Medical School, Singapore, Singapore.,Singapore Eye Research Institute, Singapore, Singapore
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22
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Tay HM, Leong SY, Xu X, Kong F, Upadya M, Dalan R, Tay CY, Dao M, Suresh S, Hou HW. Direct isolation of circulating extracellular vesicles from blood for vascular risk profiling in type 2 diabetes mellitus. Lab Chip 2021; 21:2511-2523. [PMID: 34042931 DOI: 10.1039/d1lc00333j] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Extracellular vesicles (EVs) are key mediators of communication among cells, and clinical utilities of EVs-based biomarkers remain limited due to difficulties in isolating EVs from whole blood reliably. We report a novel inertial-based microfluidic platform for direct isolation of nanoscale EVs (exosomes, 50 to 200 nm) and medium-sized EVs (microvesicles, 200 nm to 1 μm) from blood with high efficiency (three-fold increase in EV yield compared to ultracentrifugation). In a pilot clinical study of healthy (n = 5) and type 2 diabetes mellitus (T2DM, n = 9) subjects, we detected higher EV levels in T2DM patients (P < 0.05), and identified a subset of "high-risk" T2DM subjects with abnormally high (∼10-fold to 50-fold) amounts of platelet (CD41a+) or leukocyte-derived (CD45+) EVs. Our in vitro endothelial cell assay further revealed that EVs from "high-risk" T2DM subjects induced significantly higher vascular inflammation (ICAM-1 expression) (P < 0.05) as compared to healthy and non-"high-risk" T2DM subjects, reflecting a pro-inflammatory phenotype. Overall, the EV isolation tool is scalable, and requires less manual labour, cost and processing time. This enables further development of EV-based diagnostics, whereby a combined immunological and functional phenotyping strategy can potentially be used for rapid vascular risk stratification in T2DM.
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Affiliation(s)
- Hui Min Tay
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Block N3, 639798, Singapore.
| | - Sheng Yuan Leong
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Block N3, 639798, Singapore.
| | - Xiaohan Xu
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Block N3, 639798, Singapore.
| | - Fang Kong
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551, Singapore
| | - Megha Upadya
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551, Singapore
| | - Rinkoo Dalan
- Endocrine and Diabetes, Tan Tock Seng Hospital, 11 Jalan Tan Tock Seng, 308433, Singapore and Lee Kong Chian School of Medicine, Nanyang Technological University, 11 Mandalay Road, Clinical Sciences Building, 308232, Singapore
| | - Chor Yong Tay
- School of Material Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Block N4.1, 639798, Singapore.
| | - Ming Dao
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551, Singapore and Department of Material Science and Engineering, Massachusetts Institute of Technology, 182 Memorial Dr, Cambridge, MA 02142, USA
| | - Subra Suresh
- School of Material Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Block N4.1, 639798, Singapore.
| | - Han Wei Hou
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Block N3, 639798, Singapore. and Lee Kong Chian School of Medicine, Nanyang Technological University, 11 Mandalay Road, Clinical Sciences Building, 308232, Singapore
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Tay HM, Hua C. Chiral Coordination Polymers of Mandelate and its Derivatives: Tuning Crystal Packing by Modulation of Hydrogen Bonding. Aust J Chem 2021. [DOI: 10.1071/ch21066] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Chiral coordination polymers constructed from mandelic acid have shown promise in enantioselective recognition and sensing, whereas its methoxy-protected derivative, α-methoxyphenyl acetic acid, is rarely used as a ligand in coordination polymers. In this study, mandelic acid, 3,5-difluoromandelic acid, and α-methoxyphenyl acetic acid were combined with divalent transition metals and bridging dipyridyl co-ligands to obtain a series of six 1D coordination polymers. The coordination polymers of mandelate and 3,5-difluoromandelate possessed densely packed structures stabilised by hydrogen bonding. In contrast, the use of (R)-α-methoxyphenyl acetic acid gave rise to zig-zag chains with significant solvent-accessible void space.
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Abstract
This review summarises recent developments in the use of macrocyclic and mechanically-interlocked host molecules as optical sensors for anions.
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Affiliation(s)
- Hui Min Tay
- Chemistry Research Laboratory
- Department of Chemistry
- University of Oxford
- Oxford
- UK
| | - Paul Beer
- Chemistry Research Laboratory
- Department of Chemistry
- University of Oxford
- Oxford
- UK
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26
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Liu C, Teo MHY, Pek SLT, Wu X, Leong ML, Tay HM, Hou HW, Ruedl C, Moss SE, Greenwood J, Tavintharan S, Hong W, Wang X. A Multifunctional Role of Leucine-Rich α-2-Glycoprotein 1 in Cutaneous Wound Healing Under Normal and Diabetic Conditions. Diabetes 2020; 69:2467-2480. [PMID: 32887674 PMCID: PMC7576570 DOI: 10.2337/db20-0585] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 08/24/2020] [Indexed: 12/26/2022]
Abstract
Delayed wound healing is commonly associated with diabetes. It may lead to amputation and death if not treated in a timely fashion. Limited treatments are available partially due to the poor understanding of the complex disease pathophysiology. Here, we investigated the role of leucine-rich α-2-glycoprotein 1 (LRG1) in normal and diabetic wound healing. First, our data showed that LRG1 was significantly increased at the inflammation stage of murine wound healing, and bone marrow-derived cells served as a major source of LRG1. LRG1 deletion causes impaired immune cell infiltration, reepithelialization, and angiogenesis. As a consequence, there is a significant delay in wound closure. On the other hand, LRG1 was markedly induced in diabetic wounds in both humans and mice. LRG1-deficient mice were resistant to diabetes-induced delay in wound repair. We further demonstrated that this could be explained by the mitigation of increased neutrophil extracellular traps (NETs) in diabetic wounds. Mechanistically, LRG1 mediates NETosis in an Akt-dependent manner through TGFβ type I receptor kinase ALK5. Taken together, our studies demonstrated that LRG1 derived from bone marrow cells is required for normal wound healing, revealing a physiological role for this glycoprotein, but that excess LRG1 expression in diabetes is pathogenic and contributes to chronic wound formation.
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Affiliation(s)
- Chenghao Liu
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
| | - Melissa Hui Yen Teo
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Singapore
| | | | - Xiaoting Wu
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - Mei Ling Leong
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - Hui Min Tay
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore
| | - Han Wei Hou
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore
| | - Christiane Ruedl
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - Stephen E Moss
- Institute of Ophthalmology, University College London, London, U.K
| | - John Greenwood
- Institute of Ophthalmology, University College London, London, U.K
| | - Subramaniam Tavintharan
- Clinical Research Unit, Khoo Teck Puat Hospital, Singapore
- Diabetes Centre, Admiralty Medical Centre, Singapore
- Division of Endocrinology, Department of Medicine, Khoo Teck Puat Hospital, Singapore
| | - Wanjin Hong
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Singapore
| | - Xiaomeng Wang
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Singapore
- Singapore Eye Research Institute, The Academia, Singapore
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Menon NV, Su C, Pang KT, Phua ZJ, Tay HM, Dalan R, Wang X, Li KHH, Hou HW. Recapitulating atherogenic flow disturbances and vascular inflammation in a perfusable 3D stenosis model. Biofabrication 2020; 12:045009. [PMID: 32650321 DOI: 10.1088/1758-5090/aba501] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Blood vessel narrowing and arterial occlusion are pathological hallmarks of atherosclerosis, which involves a complex interplay of perturbed hemodynamics, endothelial dysfunction and inflammatory cascade. Herein, we report a novel circular microfluidic stenosis model that recapitulates atherogenic flow-mediated endothelial dysfunction and blood-endothelial cell (EC) interactions in vitro. 2D and 3D stenosis microchannels with different constriction geometries were fabricated using 3D printing to study flow disturbances under varying severity of occlusion and wall shear stresses (100 to 2000 dynecm-2). Experimental and fluid simulation results confirmed the presence of pathological shear stresses in the stenosis region, and recirculation flow post stenosis. The resultant pathological flow profile induced pro-inflammatory and pro-thrombotic EC state as demonstrated by orthogonal EC alignment, enhanced platelet adhesion at the stenosis, and aberrant leukocyte-EC interactions post stenosis. Clinical utility of the vascular model was further investigated by testing anti-thrombotic and immunomodulatory efficacy of aspirin and metformin, respectively. Overall, the platform enables multi-factorial analysis of critical atherogenic events including endothelial dysfunction, platelets and leukocyte adhesion, and can be further developed into a liquid biopsy tool for cardiovascular risk stratification.
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Affiliation(s)
- Nishanth Venugopal Menon
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 639798, Singapore. Equal contribution
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28
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Tay HM, Yeap WH, Dalan R, Wong SC, Hou HW. Increased monocyte-platelet aggregates and monocyte-endothelial adhesion in healthy individuals with vitamin D deficiency. FASEB J 2020; 34:11133-11142. [PMID: 32627899 DOI: 10.1096/fj.202000822r] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 05/26/2020] [Accepted: 06/15/2020] [Indexed: 12/31/2022]
Abstract
Vitamin D deficiency is a major public health problem worldwide, linked to several chronic diseases including cardiovascular diseases. While immunomodulatory effects of vitamin D on monocytes have been reported in cardiovascular and metabolic diseases, there is limited understanding on monocyte phenotype in healthy individuals with suboptimal vitamin D levels and without any clinical diseases. In this work, we performed label-free, microfluidic isolation of monocytes, and characterized their functional phenotype using flow cytometry and in vitro vascular models in healthy subjects with (n = 7) and without vitamin D deficiency (n = 16). Vitamin D deficient (VitD-Def) subjects (25(OH)D3 level < 26 ng/mL) expressed significant downregulation of vitamin D receptor (VDR) on monocytes as compared to controls (P < .0001), and VDR expression was well-associated with serum 25(OH)D3 levels. Increased monocyte-platelet aggregates (MPA), a marker for platelet activation, were also observed in VitD-Def subjects (P < .05) which suggests a pro-inflammatory monocyte phenotype. Monocyte adhesion to endothelial cells, an early-stage atherosclerosis event, was also higher in VitD-Def individuals, and inversely correlated to serum 25(OH)D3 level (P < .05). Taken together, these results indicate the pro-inflammatory state and atherogenic potential of monocytes in VitD-Def healthy subjects, and propound the use of vitamin D supplementation as a prospective immunomodulatory and anti-inflammatory therapy in atherosclerosis.
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Affiliation(s)
- Hui Min Tay
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, Singapore
| | - Wei Hseun Yeap
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Rinkoo Dalan
- Endocrine and Diabetes, Tan Tock Seng Hospital, Singapore, Singapore.,Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Siew Cheng Wong
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (A*STAR), Singapore, Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Han Wei Hou
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, Singapore.,Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
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29
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Abstract
Solid-state 13C NMR was used to differentiate the d- and l-enantiomers of three BOC-protected amino acids (Ala, Val, Pro) when appended to the chiral S-Mg2dobpdc MOF.
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Affiliation(s)
- Hui Min Tay
- School of Chemistry
- The University of Melbourne
- Parkville
- Australia
| | - Aditya Rawal
- Mark Wainwright Analytical Centre
- University of New South Wales
- Kensington
- Australia
| | - Carol Hua
- School of Chemistry
- The University of Melbourne
- Parkville
- Australia
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30
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Abstract
The reaction of a semi-rigid chiral ligand with Co(ii) and dipyridyl co-ligands of varying length yielded a series of 2D coordination frameworks, with the topology of the network mediated by the length of the co-ligands.
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Affiliation(s)
- Hui Min Tay
- School of Chemistry
- The University of Melbourne
- Parkville
- Australia
| | - Carol Hua
- School of Chemistry
- The University of Melbourne
- Parkville
- Australia
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31
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Petchakup C, Tay HM, Li KHH, Hou HW. Integrated inertial-impedance cytometry for rapid label-free leukocyte isolation and profiling of neutrophil extracellular traps (NETs). Lab Chip 2019; 19:1736-1746. [PMID: 31020286 DOI: 10.1039/c9lc00250b] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Circulating leukocytes are indispensable components of the immune system, and rapid analysis of their native state or functionalities can help to unravel their pathophysiological roles and identify novel prognostic biomarkers in health and diseases. Herein we report a novel high throughput "sample-in-answer-out" integrated platform for continuous leukocyte sorting and single-cell electrical profiling in a label-free manner. The multi-staged platform enables isolation of neutrophils and monocytes from diluted or lysed blood samples directly within minutes based on Dean flow fractionation (DFF) (stage 1). Next DFF-purified leukocytes are inertially focused in serpentine channels into a single stream (stage 2) prior to impedance detection (stage 3). As a proof-of-concept for neutrophil functional characterization towards diabetes testing, we characterized the formation of neutrophil extracellular traps (NETosis) of healthy and glucose-treated neutrophils and observed significant changes in dielectric properties (size and opacity) between both groups. Interestingly, the NETosis profiles induced by calcium ionophore (CaI) and phorbol 12-myristate 13-acetate (PMA) were also electrically different, which could be attributed to the differential rates of cell enlargement and attenuated membrane permeability. Taken together, these results clearly demonstrated the potential of the developed platform for rapid (∼mins) and label-free leukocyte profiling and the use of impedance signatures as novel functional biomarkers for point-of-care testing in diabetes.
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Affiliation(s)
- Chayakorn Petchakup
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Block N3, 639798 Singapore.
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Abstract
A series of lanthanide chloranilate frameworks containing a (4,4)-net with LaIII, CeIII, NdIII, SmIII, and EuIII have been synthesised and structurally characterised. Two structure types of square grids were obtained for these frameworks. Type 1 consists of the formula (Et4N)[Ln(can)2(H2O)] (Ln=LaIII, CeIII, NdIII; H2can=chloranilic acid) and crystallised in the tetragonal space group I4/m, featuring a nine-coordinate lanthanide ion with a coordinated water molecule and four chloranilate ligands. Type 2, (Et4N)[Ln(can)2] (SmIII and EuIII) crystallised in the I4/mcm space group, and contains an eight-coordinate lanthanide ion without a coordinated water molecule. A single-crystal-to-single-crystal transformation was carried out for (Et4N)[Nd(can)2(H2O)] on removal of the coordinated aqua ligand.
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34
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Tay HM, Yeap WH, Dalan R, Wong SC, Hou HW. Multiplexed Label-Free Fractionation of Peripheral Blood Mononuclear Cells for Identification of Monocyte–Platelet Aggregates. Anal Chem 2018; 90:14535-14542. [DOI: 10.1021/acs.analchem.8b04415] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Hui Min Tay
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
| | - Wei Hseun Yeap
- Singapore Immunology Network, Agency for Science, Technology and Research, 8a Biomedical Grove, 138648, Singapore
| | - Rinkoo Dalan
- Endocrine and Diabetes, Tan Tock Seng Hospital, 11 Jalan Tan Tock Seng, 308433, Singapore
| | - Siew Cheng Wong
- Singapore Immunology Network, Agency for Science, Technology and Research, 8a Biomedical Grove, 138648, Singapore
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551, Singapore
| | - Han Wei Hou
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Clinical Sciences Building, 11 Mandalay Road, 308232, Singapore
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35
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Pang K, Fhu CW, Ghim M, Tay HM, Hou HW, Lu Q, Warboys CM, Wang X, Weinberg PD. 53LRG1 is a novel regulator of endothelial activation and is shear dependent: a potential therapeutic target? Cardiovasc Res 2018. [DOI: 10.1093/cvr/cvy060.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- K Pang
- Imperial College London, Department of Bioengineering, London, United Kingdom
| | - C W Fhu
- Nanyang Technological University, Lee Kong Chian School of Medicine, Singapore, Singapore
| | - M Ghim
- Imperial College London, Department of Bioengineering, London, United Kingdom
| | - H M Tay
- Nanyang Technological University, Lee Kong Chian School of Medicine, Singapore, Singapore
| | - H W Hou
- Nanyang Technological University, Lee Kong Chian School of Medicine, Singapore, Singapore
| | - Q Lu
- Imperial College London, Department of Life Sciences, London, United Kingdom
| | - C M Warboys
- Imperial College London, Department of Bioengineering, London, United Kingdom
| | - X Wang
- Nanyang Technological University, Lee Kong Chian School of Medicine, Singapore, Singapore
| | - P D Weinberg
- Imperial College London, Department of Bioengineering, London, United Kingdom
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36
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Tay HM, Dalan R, Li KHH, Boehm BO, Hou HW. A Novel Microdevice for Rapid Neutrophil Purification and Phenotyping in Type 2 Diabetes Mellitus. Small 2018; 14:1702832. [PMID: 29168915 DOI: 10.1002/smll.201702832] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 09/21/2017] [Indexed: 06/07/2023]
Abstract
Neutrophil dysfunction is strongly linked to type 2 diabetes mellitus (T2DM) pathophysiology, but the prognostic potential of neutrophil biomarkers remains largely unexplored due to arduous leukocyte isolation methods. Herein, a novel integrated microdevice is reported for single-step neutrophil sorting and phenotyping (chemotaxis and formation of neutrophil extracellular traps (NETosis)) using small blood volumes (fingerprick). Untouched neutrophils are purified on-chip from whole blood directly using biomimetic cell margination and affinity-based capture, and are exposed to preloaded chemoattractant or NETosis stimulant to initiate chemotaxis or NETosis, respectively. Device performance is first characterized using healthy and in vitro inflamed blood samples (tumor necrosis factor alpha, high glucose), followed by clinical risk stratification in a cohort of subjects with T2DM. Interestingly, "high-risk" T2DM patients characterized by severe chemotaxis impairment reveal significantly higher C-reactive protein levels and poor lipid metabolism characteristics as compared to "low-risk" subjects, and their neutrophil chemotaxis responses can be mitigated after in vitro metformin treatment. Overall, this unique and user-friendly microfluidics immune health profiling strategy can significantly aid the quantification of chemotaxis and NETosis in clinical settings, and be further translated into a tool for risk stratification and precision medicine methods in subjects with metabolic diseases such as T2DM.
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Affiliation(s)
- Hui Min Tay
- Lee Kong Chian School of Medicine, Nanyang Technological University, 11 Mandalay Road, Clinical Sciences Building Level 11, Singapore, 308232, Singapore
| | - Rinkoo Dalan
- Endocrine and Diabetes, Tan Tock Seng Hospital, 11 Jalan Tan Tock Seng, Singapore, 308433, Singapore
| | - King Ho Holden Li
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Block N3, Singapore, 639798, Singapore
| | - Bernhard O Boehm
- Lee Kong Chian School of Medicine, Nanyang Technological University, 11 Mandalay Road, Clinical Sciences Building Level 11, Singapore, 308232, Singapore
- Endocrine and Diabetes, Tan Tock Seng Hospital, 11 Jalan Tan Tock Seng, Singapore, 308433, Singapore
| | - Han Wei Hou
- Lee Kong Chian School of Medicine, Nanyang Technological University, 11 Mandalay Road, Clinical Sciences Building Level 11, Singapore, 308232, Singapore
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Venugopal Menon N, Tay HM, Pang KT, Dalan R, Wong SC, Wang X, Li KHH, Hou HW. A tunable microfluidic 3D stenosis model to study leukocyte-endothelial interactions in atherosclerosis. APL Bioeng 2018; 2:016103. [PMID: 31069288 PMCID: PMC6481702 DOI: 10.1063/1.4993762] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 11/06/2017] [Indexed: 12/31/2022] Open
Abstract
Atherosclerosis, a chronic inflammatory disorder characterized by endothelial dysfunction and blood vessel narrowing, is the leading cause of cardiovascular diseases including heart attack and stroke. Herein, we present a novel tunable microfluidic atherosclerosis model to study vascular inflammation and leukocyte-endothelial interactions in 3D vessel stenosis. Flow and shear stress profiles were characterized in pneumatic-controlled stenosis conditions (0%, 50% and 80% constriction) using fluid simulation and experimental beads perfusion. Due to non-uniform fluid flow at the 3D stenosis, distinct monocyte (THP-1) adhesion patterns on inflamed [tumor necrosis factor-α (TNF-α) treated] endothelium were observed, and there was a differential endothelial expression of intercellular adhesion molecule-1 (ICAM-1) at the constriction region. Whole blood perfusion studies also showed increased leukocyte interactions (cell rolling and adherence) at the stenosis of healthy and inflamed endothelium, clearly highlighting the importance of vascular inflammation, flow disturbance, and vessel geometry in recapitulating atherogenic microenvironment. To demonstrate inflammatory risk assessment using leukocytes as functional biomarkers, we perfused whole blood samples into the developed microdevices (80% constriction) and observed significant dose-dependent effects of leukocyte adhesion in healthy and inflamed (TNF-α treated) blood samples. Taken together, the 3D stenosis chip facilitates quantitative study of hemodynamics and leukocyte-endothelial interactions, and can be further developed into a point-of-care blood profiling device for atherosclerosis and other vascular diseases.
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Affiliation(s)
- Nishanth Venugopal Menon
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798
| | - Hui Min Tay
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 308232
| | | | - Rinkoo Dalan
- Endocrinology Department, Tan Tock Seng Hospital, Singapore 308433
| | - Siew Cheng Wong
- Singapore Immunology Network, Agency for Science, Technology and Research, Singapore 138648
| | | | - King Ho Holden Li
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798
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Fan YL, Hou HW, Tay HM, Guo WM, Berggren PO, Loo SCJ. Preservation of Anticancer and Immunosuppressive Properties of Rapamycin Achieved Through Controlled Releasing Particles. AAPS PharmSciTech 2017; 18:2648-2657. [PMID: 28251512 DOI: 10.1208/s12249-017-0745-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 02/14/2017] [Indexed: 12/24/2022] Open
Abstract
Rapamycin is commonly used in chemotherapy and posttransplantation rejection suppression, where sustained release is preferred. Conventionally, rapamycin has to be administered in excess due to its poor solubility, and this often leads to cytotoxicity and undesirable side effects. In addition, rapamycin has been shown to be hydrolytically unstable, losing its bioactivity within a few hours. The use of drug delivery systems is hypothesized to preserve the bioactivity of rapamycin, while providing controlled release of this otherwise potent drug. This paper reports on the use of microparticles (MP) as a means to tune and sustain the delivery of bioactive rapamycin for up to 30 days. Rapamycin was encapsulated (100% efficiency) in poly(lactic-co-glycolic acid) (PLGA), polycaprolactone (PCL), or a mixture of both via an emulsion method. The use of different polymer types and mixture was shown to achieve a variety of release kinetics and profile. Released rapamycin was subsequently evaluated against breast cancer cell (MCF-7) and human lymphocyte cell (Jurkat). Inhibition of cell proliferation was in good agreement with in vitro release profiles, which confirmed the intact bioactivity of rapamycin. For Jurkat cells, the suppression of cell growth was proven to be effective up to 20 days, a duration significantly longer than free rapamycin. Taken together, these results demonstrate the ability to tune, sustain, and preserve the bioactivity of rapamycin using MP formulations. The sustained delivery of rapamycin could lead to better therapeutic effects than bolus dosage, at the same time improving patient compliance due to its long-acting duration.
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Abstract
Vessel geometries in microengineered in vitro vascular models are important to recapitulate a pathophysiological microenvironment for the study of flow-induced endothelial dysfunction and inflammation in cardiovascular diseases. Herein, we present a simple and novel extracellular matrix (ECM) hydrogel patterning method to create perfusable vascularized microchannels of different geometries based on the concept of capillary burst valve (CBV). No surface modification is necessary and the method is suitable for different ECM types including collagen, matrigel and fibrin. We first created collagen-patterned, endothelialized microchannels to study barrier permeability and neutrophil transendothelial migration, followed by the development of a biomimetic 3D endothelial-smooth muscle cell (EC-SMC) vascular model. We observed a significant decrease in barrier permeability in the co-culture model during inflammation, which indicates the importance of perivascular cells in ECM remodeling. Finally, we engineered collagen-patterned constricted vascular microchannels to mimic stenosis in atherosclerosis. Whole blood was perfused (1-10 dyne cm-2) into the microdevices and distinct platelet and leukocyte adherence patterns were observed due to increased shear stresses at the constriction, and an additional convective flow through the collagen. Taken together, the developed hydrogel patterning technique enables the formation of unique pathophysiological architectures in organ-on-chip microsystems for real-time study of hemodynamics and cellular interactions in cardiovascular diseases.
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Affiliation(s)
- Nishanth Venugopal Menon
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Block N3, Singapore 639798
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40
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Abstract
Engineering cells with active-ingredient-loaded micro/nanoparticles (NPs) is becoming an increasingly popular method to enhance native therapeutic properties, enable bio imaging and control cell phenotype. A critical yet inadequately addressed issue is the significant number of particles that remain unbound after cell labeling which cannot be readily removed by conventional centrifugation. This leads to an increase in bio imaging background noise and can impart transformative effects onto neighboring non-target cells. In this protocol, we present an inertial microfluidics-based buffer exchange strategy termed as Dean Flow Fractionation (DFF) to efficiently separate labeled cells from free NPs in a high throughput manner. The developed spiral microdevice facilitates continuous collection (>90% cell recovery) of purified cells (THP-1 and MSCs) suspended in new buffer solution, while achieving >95% depletion of unbound fluorescent dye or dye-loaded NPs (silica or PLGA). This single-step, size-based cell purification strategy enables high cell processing throughput (10(6) cells/min) and is highly useful for large-volume cell purification of micro/nanoparticle engineered cells to achieve interference-free clinical application.
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Affiliation(s)
- Hui Min Tay
- Lee Kong Chian School of Medicine, Nanyang Technological University
| | - David C Yeo
- School of Chemical and Biomedical Engineering, Nanyang Technological University
| | - Christian Wiraja
- School of Chemical and Biomedical Engineering, Nanyang Technological University
| | - Chenjie Xu
- School of Chemical and Biomedical Engineering, Nanyang Technological University; NTU-Northwestern Institute of Nanomedicine, Nanyang Technological University;
| | - Han Wei Hou
- Lee Kong Chian School of Medicine, Nanyang Technological University;
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41
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Hou HW, Petchakup C, Tay HM, Tam ZY, Dalan R, Chew DEK, Li KHH, Boehm BO. Rapid and label-free microfluidic neutrophil purification and phenotyping in diabetes mellitus. Sci Rep 2016; 6:29410. [PMID: 27381673 PMCID: PMC4933935 DOI: 10.1038/srep29410] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Accepted: 06/16/2016] [Indexed: 01/13/2023] Open
Abstract
Advanced management of dysmetabolic syndromes such as diabetes will benefit from a timely mechanistic insight enabling personalized medicine approaches. Herein, we present a rapid microfluidic neutrophil sorting and functional phenotyping strategy for type 2 diabetes mellitus (T2DM) patients using small blood volumes (fingerprick ~100 μL). The developed inertial microfluidics technology enables single-step neutrophil isolation (>90% purity) without immuno-labeling and sorted neutrophils are used to characterize their rolling behavior on E-selectin, a critical step in leukocyte recruitment during inflammation. The integrated microfluidics testing methodology facilitates high throughput single-cell quantification of neutrophil rolling to detect subtle differences in speed distribution. Higher rolling speed was observed in T2DM patients (P < 0.01) which strongly correlated with neutrophil activation, rolling ligand P-selectin glycoprotein ligand 1 (PSGL-1) expression, as well as established cardiovascular risk factors (cholesterol, high-sensitive C-reactive protein (CRP) and HbA1c). Rolling phenotype can be modulated by common disease risk modifiers (metformin and pravastatin). Receiver operating characteristics (ROC) and principal component analysis (PCA) revealed neutrophil rolling as an important functional phenotype in T2DM diagnostics. These results suggest a new point-of-care testing methodology, and neutrophil rolling speed as a functional biomarker for rapid profiling of dysmetabolic subjects in clinical and patient-oriented settings.
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Affiliation(s)
- Han Wei Hou
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
| | - Chayakorn Petchakup
- Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore
| | - Hui Min Tay
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
| | - Zhi Yang Tam
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
| | - Rinkoo Dalan
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore.,Endocrine and Diabetes, Tan Tock Seng Hospital, Singapore
| | - Daniel Ek Kwang Chew
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore.,Endocrine and Diabetes, Tan Tock Seng Hospital, Singapore
| | - King Ho Holden Li
- Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore
| | - Bernhard O Boehm
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore.,Endocrine and Diabetes, Tan Tock Seng Hospital, Singapore.,Imperial College London, UK
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Yeo DC, Wiraja C, Zhou Y, Tay HM, Xu C, Hou HW. Interference-free Micro/nanoparticle Cell Engineering by Use of High-Throughput Microfluidic Separation. ACS Appl Mater Interfaces 2015; 7:20855-20864. [PMID: 26355568 DOI: 10.1021/acsami.5b06167] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Engineering cells with active-ingredient-loaded micro/nanoparticles is becoming increasingly popular for imaging and therapeutic applications. A critical yet inadequately addressed issue during its implementation concerns the significant number of particles that remain unbound following the engineering process, which inadvertently generate signals and impart transformative effects onto neighboring nontarget cells. Here we demonstrate that those unbound micro/nanoparticles remaining in solution can be efficiently separated from the particle-labeled cells by implementing a fast, continuous, and high-throughput Dean flow fractionation (DFF) microfluidic device. As proof-of-concept, we applied the DFF microfluidic device for buffer exchange to sort labeled suspension cells (THP-1) from unbound fluorescent dye and dye-loaded micro/nanoparticles. Compared to conventional centrifugation, the depletion efficiency of free dyes or particles was improved 20-fold and the mislabeling of nontarget bystander cells by free particles was minimized. The microfluidic device was adapted to further accommodate heterogeneous-sized mesenchymal stem cells (MSCs). Complete removal of unbound nanoparticles using DFF led to the usage of engineered MSCs without exerting off-target transformative effects on the functional properties of neighboring endothelial cells. Apart from its effectiveness in removing free particles, this strategy is also efficient and scalable. It could continuously process cell solutions with concentrations up to 10(7) cells·mL(-1) (cell densities commonly encountered during cell therapy) without observable loss of performance. Successful implementation of this technology is expected to pave the way for interference-free clinical application of micro/nanoparticle engineered cells.
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Affiliation(s)
- David C Yeo
- School of Chemical & Biomedical Engineering, Nanyang Technological University , 62 Nanyang Drive, Singapore 637459
| | - Christian Wiraja
- School of Chemical & Biomedical Engineering, Nanyang Technological University , 62 Nanyang Drive, Singapore 637459
| | - Yingying Zhou
- School of Chemical & Biomedical Engineering, Nanyang Technological University , 62 Nanyang Drive, Singapore 637459
| | - Hui Min Tay
- Lee Kong Chian School of Medicine, Nanyang Technological University , 50 Nanyang Drive, Singapore 637553
| | - Chenjie Xu
- School of Chemical & Biomedical Engineering, Nanyang Technological University , 62 Nanyang Drive, Singapore 637459
- NTU-Northwestern Institute of Nanomedicine, Nanyang Technological University , 50 Nanyang Avenue, Singapore 639798
| | - Han Wei Hou
- Lee Kong Chian School of Medicine, Nanyang Technological University , 50 Nanyang Drive, Singapore 637553
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