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1.
Bioengineering (Basel) ; 11(6)2024 Jun 08.
Article in English | MEDLINE | ID: mdl-38927821

ABSTRACT

Securing high-quality cell sources is important in regenerative medicine. In this study, we developed a device that can accumulate autologous stem cells in the body. When small wire-assembled molds were embedded in the dorsal subcutaneous pouches of beagles for several weeks, collagen-based tissues with minimal inflammation formed inside the molds. At 3 weeks of embedding, the outer areas of the tissues were composed of immature type III collagen with large amounts of cells expressing SSEA3 or SSEA4 markers, in addition to growth factors such as HGF or VEGF. When separated from the tissues by collagenase treatment, approximately four million cells with a proportion of 70% CD90-positive and 20% SSEA3- or SSEA4-positive cells were recovered from the single mold. The cells could differentiate into bone or cartilage cells. The obtained cell-containing tissues are expected to have potential as therapeutic materials or cell sources in regenerative medicine.

2.
Micromachines (Basel) ; 15(4)2024 Mar 28.
Article in English | MEDLINE | ID: mdl-38675267

ABSTRACT

The capture of individual cells using microfluidic chips represents a widely adopted and efficient approach for investigating the biochemical microenvironment of singular cells. While conventional methods reliant on boundary effects pose challenges in precisely manipulating individual cells, single-cell capture grounded in the principle of stagnation point flow offers a solution to this limitation. Nevertheless, such capture mechanisms encounter inconsistency due to the instability of the flow field and stagnation point. In this study, a microfluidic device for the stable capture of single cells was designed, integrating the principle of fluid mechanics by amalgamating stagnation point flow and boundary effects. This innovative microfluidic chip transcended the limitations associated with single methodologies, leveraging the strengths of both stagnation point flow and boundary effects to achieve reliable single-cell capture. Notably, the incorporation of capture ports at the stagnation point not only harnessed boundary effects but also enhanced capture efficiency significantly, elevating it from 31.9% to 83.3%, thereby augmenting capture stability. Furthermore, computational simulations demonstrated the efficacy of the capture ports in entrapping particles of varying diameters, including 9 µm, 14 µm, and 18 µm. Experiment validation underscored the capability of this microfluidic system to capture single cells within the chip, maintaining stability even under flow rate perturbations spanning from 60 µL/min to 120 µL/min. Consequently, cells with dimensions between 8 µm and 12 µm can be reliably captured. The designed microfluidic system not only furnishes a straightforward and efficient experimental platform but also holds promise for facilitating deeper investigations into the intricate interplay between individual cells and their surrounding microenvironment.

3.
Micromachines (Basel) ; 15(4)2024 Apr 13.
Article in English | MEDLINE | ID: mdl-38675332

ABSTRACT

A high porosity micropore arrayed parylene membrane is a promising device that is used to capture circulating and exfoliated tumor cells (CTCs and ETCs) for liquid biopsy applications. However, its fabrication still requires either expensive equipment or an expensive process. Here, we report on the fabrication of high porosity (>40%) micropore arrayed parylene membranes through a simple reactive ion etching (RIE) that uses photoresist as the etching mask. Vertical sidewalls were observed in etched parylene pores despite the sloped photoresist mask sidewalls, which was found to be due to the simultaneous high DC-bias RIE induced photoresist melting and substrate pedestal formation. A theoretical model has been derived to illustrate the dependence of the maximum membrane thickness on the final pore-to-pore spacing, and it is consistent with the experimental data. A simple, yet accurate, low number (<50) cell counting method was demonstrated through counting cells directly inside a pipette tip under phase-contrast microscope. Membranes as thin as 3 µm showed utility for low number tumor cell capture, with an efficiency of 87-92%.

4.
Angew Chem Int Ed Engl ; 63(19): e202402123, 2024 May 06.
Article in English | MEDLINE | ID: mdl-38453654

ABSTRACT

Triplex DNA switches are attractive allosteric tools for engineering smart nanodevices, but their poor triplex-forming capacity at physiological conditions limited the practical applications. To address this challenge, we proposed a low-entropy barrier design to facilitate triplex formation by introducing a hairpin duplex linker into the triplex motif, and the resulting triplex switch was termed as CTNSds. Compared to the conventional clamp-like triplex switch, CTNSds increased the triplex-forming ratio from 30 % to 91 % at pH 7.4 and stabilized the triple-helix structure in FBS and cell lysate. CTNSds was also less sensitive to free-energy disturbances, such as lengthening linkers or mismatches in the triple-helix stem. The CTNSds design was utilized to reversibly isolate CTCs from whole blood, achieving high capture efficiencies (>86 %) at pH 7.4 and release efficiencies (>80 %) at pH 8.0. Our approach broadens the potential applications of DNA switches-based switchable nanodevices, showing great promise in biosensing and biomedicine.


Subject(s)
DNA , Hydrogen-Ion Concentration , DNA/chemistry , Humans , Entropy , Nucleic Acid Conformation , Biosensing Techniques
5.
J Neurooncol ; 167(3): 509-514, 2024 May.
Article in English | MEDLINE | ID: mdl-38441840

ABSTRACT

PURPOSE: Treatment decisions for leptomeningeal disease (LMD) rely on patient risk stratification, since clinicians lack objective prognostic tools. The introduction of rare cell capture technology for identification of cerebrospinal fluid tumor cells (CSF-TCs), such as CNSide assay, improved the sensitivity of LMD diagnosis, but prognostic value is unknown. This study assesses the prognostic value of CSF-TC density in patients with LMD from solid tumors. METHODS: We conducted a retrospective cohort study of patients with newly diagnosed or previously treated LMD from a single institution who had CNSide assay testing for CSF-TCs from 2020 to 2023. Univariable and multivariable survival analyses were conducted with Cox proportional-hazards modeling. Maximally-selected rank statistics were used to determine an optimal cutpoint for CSF-TC density and survival. RESULTS: Of 31 patients, 29 had CSF-TCs detected on CNSide. Median (interquartile range [IQR]) CSF-TC density was 67.8 (4.7-639) TCs/mL. CSF cytology was positive in 16 of 29 patients with positive CNSide (CNSide diagnostic sensitivity = 93.5%, negative predictive value = 85.7%). Median (IQR) survival from time of CSF-TC detection was 176 (89-481) days. On univariable and multivariable analysis, CSF-TC density was significantly associated with survival. An optimal cutpoint for dichotomizing survival by CSF-TC density was 19.34 TCs/mL. The time-dependent sensitivity and specificity for survival using this stratification were 76% and 67% at 6 months and 65% and 67% at 1 year, respectively. CONCLUSIONS: CSF-TC density may carry prognostic value in patients with LMD from solid tumors. Integrating CSF-TC density into LMD patient risk-stratification may help guide treatment decisions.


Subject(s)
Meningeal Neoplasms , Humans , Retrospective Studies , Female , Male , Prognosis , Middle Aged , Meningeal Neoplasms/cerebrospinal fluid , Meningeal Neoplasms/mortality , Meningeal Neoplasms/diagnosis , Meningeal Neoplasms/pathology , Aged , Adult , Survival Rate , Follow-Up Studies , Neoplasms/cerebrospinal fluid , Neoplasms/mortality , Neoplasms/diagnosis , Neoplasms/pathology , Meningeal Carcinomatosis/cerebrospinal fluid , Meningeal Carcinomatosis/diagnosis , Meningeal Carcinomatosis/mortality , Cell Count
6.
Biosensors (Basel) ; 13(7)2023 Jul 04.
Article in English | MEDLINE | ID: mdl-37504105

ABSTRACT

Liquid biopsy has progressed to its current use to diagnose and monitor cancer. Despite the recent advances in investigating cancer detection and diagnosis strategies, there is still a room for improvements in capturing CTCs. We developed an efficient CTC detection system by integrating gold nanoparticles with a microfluidic platform, which can achieve CTC capture within 120 min. Here, we report our development of a simple and effective way to isolate CTCs using antibodies attached on gold nanoparticles to the surface of a lateral filter array (LFA) microdevice. Our method was optimized using three pancreatic tumor cell lines, enabling the capture with high efficiency (90% ± 3.2%). The platform was further demonstrated for isolating CTCs from patients with metastatic pancreatic cancer. Our method and platform enables the production of functionalized, patterned surfaces that interact with tumor cells, enhancing the selective capture of CTCs for biological assays.


Subject(s)
Metal Nanoparticles , Microfluidic Analytical Techniques , Neoplastic Cells, Circulating , Humans , Microfluidics/methods , Neoplastic Cells, Circulating/metabolism , Gold , Cell Line, Tumor
7.
Anal Chim Acta ; 1274: 341556, 2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37455076

ABSTRACT

Circulating tumor cells (CTCs) have now emerged as a type of promising circulating biomarkers in liquid biopsy and can predict the occurrence and development of cancers. In this work, an integrated and renewable interface is fabricated for the capture, release and quantitative analysis of CTCs. As designed, folate receptor-positive CTCs are captured by folic acid-modified DNA probes at the interface through the receptor-ligand interaction, and are efficiently released from the interface with the aid of bleomycin-ferrous complex-regulated cleavage. Taking MCF-7 cells as the model, the functional interface demonstrates high efficiency to selectively capture the folate receptor-positive tumor cells, and the bleomycin-ferrous complex-regulated cleavage not only easily releases the captured cells with well-maintained viability and proliferation ability, but also releases silver nanoparticles that are labeled at the cell surface for highly sensitive quantification by adopting electrochemical techniques with a detection limit of 6 cells/mL. At the meanwhile, the interface is proved to be regenerated through a simple cleavage-hybridization event and reused with high stability. Therefore, our work may provide a new idea for the collection and downstream researches of circulating tumor cells in the future.


Subject(s)
Metal Nanoparticles , Neoplastic Cells, Circulating , Humans , Neoplastic Cells, Circulating/pathology , Silver , MCF-7 Cells , Folic Acid , Cell Line, Tumor , Cell Separation/methods
8.
Microbiol Spectr ; 11(4): e0111423, 2023 08 17.
Article in English | MEDLINE | ID: mdl-37358439

ABSTRACT

Mycobacterium tuberculosis whole-genome sequencing (WGS) is a powerful tool as it can provide data on population diversity, drug resistance, disease transmission, and mixed infections. Successful WGS is still reliant on high concentrations of DNA obtained through M. tuberculosis culture. Microfluidics technology plays a valuable role in single-cell research but has not yet been assessed as a bacterial enrichment strategy for culture-free WGS of M. tuberculosis. In a proof-of-principle study, we evaluated the use of Capture-XT, a microfluidic lab-on-chip cleanup and pathogen concentration platform to enrich M. tuberculosis bacilli from clinical sputum specimens for downstream DNA extraction and WGS. Three of the four (75%) samples processed by the microfluidics application passed the library preparation quality control, compared to only one of the four (25%) samples not enriched by the microfluidics M. tuberculosis capture application. WGS data were of sufficient quality, with mapping depth of ≥25× and 9 to 27% of reads mapping to the reference genome. These results suggest that microfluidics-based M. tuberculosis cell capture might be a promising method for M. tuberculosis enrichment in clinical sputum samples, which could facilitate culture-free M. tuberculosis WGS. IMPORTANCE Diagnosis of tuberculosis is effective using molecular methods; however, a comprehensive characterization of the resistance profile of Mycobacterium tuberculosis often requires culturing and phenotypic drug susceptibility testing or culturing followed by whole-genome sequencing (WGS). The phenotypic route can take anywhere from 1 to >3 months to result, by which point the patient may have acquired additional drug resistance. The WGS route is a very attractive option; however, culturing is the rate-limiting step. In this original article, we provide proof-of-principle evidence that microfluidics-based cell capture can be used on high-bacillary-load clinical samples for culture-free WGS.


Subject(s)
Mycobacterium tuberculosis , Tuberculosis , Humans , Mycobacterium tuberculosis/genetics , Microfluidics , Microbial Sensitivity Tests , Tuberculosis/microbiology , Whole Genome Sequencing , Antitubercular Agents/pharmacology
9.
ACS Appl Mater Interfaces ; 15(20): 24013-24022, 2023 May 24.
Article in English | MEDLINE | ID: mdl-37178127

ABSTRACT

Detection of circulating tumor cells (CTCs) is important for early cancer diagnosis, prediction of postoperative recurrence, and individualized treatment. However, it is still challenging to achieve efficient capture and gentle release of CTCs from the complex peripheral blood due to their rarity and fragility. Herein, inspired by the three-dimensional (3D) network structure and high glutathione (GSH) level of the tumor microenvironment (TME), a 3D stereo (3D-G@FTP) fibrous network is developed by combining the liquid-assisted electrospinning method, gas foaming technique, and metal-polyphenol coordination interactions to achieve efficient trapping and gentle release of CTCs. Compared with the traditional 2D@FTP fibrous scaffold, the 3D-G@FTP fibrous network could achieve higher capture efficiency (90.4% vs 78.5%) toward cancer cells in a shorter time (30 min vs 90 min). This platform showed superior capture performance toward heterogeneous cancer cells (HepG2, HCT116, HeLa, and A549) in an epithelial cell adhesion molecule (EpCAM)-independent manner. In addition, the captured cells with high cell viability (>90.0%) could be gently released under biologically friendly GSH stimulus. More importantly, the 3D-G@FTP fibrous network could sensitively detect 4-19 CTCs from six kinds of cancer patients' blood samples. We expect this TME-inspired 3D stereo fibrous network integrating efficient trapping, broad-spectrum recognition, and gentle release will promote the development of biomimetic devices for rare cell analysis.


Subject(s)
Neoplastic Cells, Circulating , Humans , Neoplastic Cells, Circulating/metabolism , Glutathione , HeLa Cells , Epithelial Cell Adhesion Molecule/metabolism , Cell Line, Tumor , Cell Separation/methods , Tumor Microenvironment
10.
PNAS Nexus ; 2(5): pgad155, 2023 May.
Article in English | MEDLINE | ID: mdl-37252002

ABSTRACT

Recent advancements in micro/nanofabrication techniques have led to the development of portable devices for high-throughput single-cell analysis through the isolation of individual target cells, which are then paired with functionalized microbeads. Compared with commercially available benchtop instruments, portable microfluidic devices can be more widely and cost-effectively adopted in single-cell transcriptome and proteome analysis. The sample utilization and cell pairing rate (∼33%) of current stochastic-based cell-bead pairing approaches are fundamentally limited by Poisson statistics. Despite versatile technologies having been proposed to reduce randomness during the cell-bead pairing process in order to statistically beat the Poisson limit, improvement of the overall pairing rate of a single cell to a single bead is typically based on increased operational complexity and extra instability. In this article, we present a dielectrophoresis (DEP)-assisted dual-nanowell array (ddNA) device, which employs an innovative microstructure design and operating process that decouples the bead- and cell-loading processes. Our ddNA design contains thousands of subnanoliter microwell pairs specifically tailored to fit both beads and cells. Interdigitated electrodes (IDEs) are placed below the microwell structure to introduce a DEP force on cells, yielding high single-cell capture and pairing rates. Experimental results with human embryonic kidney cells confirmed the suitability and reproducibility of our design. We achieved a single-bead capture rate of >97% and a cell-bead pairing rate of >75%. We anticipate that our device will enhance the application of single-cell analysis in practical clinical use and academic research.

11.
Small ; 19(18): e2207154, 2023 05.
Article in English | MEDLINE | ID: mdl-36772896

ABSTRACT

The development of specific and sensitive immunomagnetic cell separation nanotechnologies is central to enhancing the diagnostic relevance of circulating tumor cells (CTCs) and improving cancer patient outcomes. The limited number of specific biomarkers used to enrich a phenotypically diverse set of CTCs from liquid biopsies has limited CTC yields and purity. The ultra-high molecular weight mucin, mucin16 (MUC16) is shown to physically shield key membrane proteins responsible for activating immune responses against ovarian cancer cells and may interfere with the binding of magnetic nanoparticles to popular immunomagnetic cell capture antigens. MUC16 is expressed in ≈90% of ovarian cancers and is almost universal in High Grade Serous Epithelial Ovarian Cancer. This work demonstrates that cell bound MUC16 is an effective target for rapid immunomagnetic extraction of expressor cells with near quantitative yield, high purity and viability from serum. The results provide a mechanistic insight into the effects of nanoparticle physical properties and immunomagnetic labeling on the efficiency of immunomagnetic cell isolation. The growth of these cells has also been studied after separation, demonstrating that nanoparticle size impacts cell-particle behavior and growth rate. These results present the successful isolation of "masked" CTCs enabling new strategies for the detection of cancer recurrence and select and monitor chemotherapy.


Subject(s)
Nanoparticles , Neoplastic Cells, Circulating , Ovarian Neoplasms , Humans , Female , Mucins , Immunomagnetic Separation/methods , Nanoparticles/chemistry , Ovarian Neoplasms/diagnosis , Membrane Proteins/metabolism , Neoplastic Cells, Circulating/pathology , Cell Line, Tumor , Cell Separation
12.
Methods Mol Biol ; 2614: 357-368, 2023.
Article in English | MEDLINE | ID: mdl-36587135

ABSTRACT

Single-cell technologies have become critical tools to understand and characterize the complex dynamics that govern biological systems, from embryonic development to cancer heterogeneity. In this context, identification and capture of live individual cells in heterogenous ensembles typically rely on genetic manipulations that encode fluorescent probes. However, a precise understanding of how several molecular components interact to yield the phenotype of interest is a prerequisite to distinguishing and isolating such target cells based on fluorescence alone. Indeed, cellular phenotypes associated with migration, shape, location, or intracellular protein distribution play critical and well-understood roles in cancer biology, but the technologies to tag and isolate cells based on information obtained from imaging are not readily available.Cell labeling via photobleaching (CLaP) and single-cell magneto-optical capture (scMOCa) represent convenient and cost-effective systems for labeling, capturing, and expanding single cells from a heterogenous population, without altering cellular physiology and therefore enabling not only transcriptomic profiling but also biological characterization of target cells. Both techniques allow capturing cells after observation and permit researchers to choose target cells based on information obtained from images. The implementation of these technologies only needs the lasers of a confocal microscope and low-cost, commercially available chemical reagents. Here, we describe a detailed protocol to set up and perform CLaP and scMOCa and highlight critical points for optimal performance.


Subject(s)
Fluorescent Dyes , Light , Fluorescent Dyes/chemistry , Photobleaching , Lasers
13.
Front Pharmacol ; 13: 982185, 2022.
Article in English | MEDLINE | ID: mdl-36299902

ABSTRACT

Stent thrombosis remains one of the main causes that lead to vascular stent failure in patients undergoing percutaneous coronary intervention (PCI). Type 2 diabetes mellitus is accompanied by endothelial dysfunction and platelet hyperactivity and is associated with suboptimal outcomes following PCI, and an increase in the incidence of late stent thrombosis. Evidence suggests that late stent thrombosis is caused by the delayed and impaired endothelialization of the lumen of the stent. The endothelium has a key role in modulating inflammation and thrombosis and maintaining homeostasis, thus restoring a functional endothelial cell layer is an important target for the prevention of stent thrombosis. Modifications using specific molecules to induce endothelial cell adhesion, proliferation and function can improve stents endothelialization and prevent thrombosis. Blood endothelial progenitor cells (EPCs) represent a potential cell source for the in situ-endothelialization of vascular conduits and stents. We aim in this review to summarize the main biofunctionalization strategies to induce the in-situ endothelialization of coronary artery stents using circulating endothelial stem cells.

14.
ACS Appl Bio Mater ; 2022 Sep 29.
Article in English | MEDLINE | ID: mdl-36174120

ABSTRACT

With circulating tumor cells (CTCs) playing a critical role in cancer metastasis, the quantitation and characterization of CTCs promise to provide precise diagnostic and prognostic information in service of personalized therapies. However, as CTCs are extremely rare, high yield, high purity strategies are required to target and isolate CTCs from patient samples. Recently, we demonstrated the selective capture of CTCs upon antibody-functionalized polyethylene glycol diacrylate (PEGDA) hydrogels photopolymerized within polydimethylsiloxane (PDMS) microfluidic molds. Isolated CTC purity was subsequently enriched by selectively releasing desired cells from photodegradable hydrogel capture surfaces. However, the fabrication of these acrylate-based hydrogels by photopolymerization is subject to oxygen inhibition, which dramatically affects the physical and chemical properties of hydrogel interfaces formed in proximity to PDMS boundaries. To evaluate how antibody conjugation density and cell capture is impacted by fabrication parameters affected by oxygen inhibition, PEGDA hydrogel features were polymerized within PDMS micromolds under different UV exposure conditions and linker (acrylate-PEG-biotin) concentrations. Predictions of acrylate conversion throughout the hydrogel feature were performed using a 1D reaction-diffusion model that describes oxygen-inhibited photopolymerization. The functional consequences of photopolymerization parameters and solution stoichiometry on CTC capture were experimentally quantified and evaluated. Results show that hydrogel surfaces polymerized under shorter exposure times and with higher linker concentrations display superior functionalization and higher CTC capture efficiency. Conversely, highly cross-linked hydrogel surfaces polymerized under longer exposure times are insensitive to functionalization and display poor capture, regardless of linker concentration. By highlighting the importance of oxygen-inhibited photopolymerization, these findings provide guidelines to design micromolded hydrogels with controlled ligand expression. In addition to enhancing the selective cell capture capacity of immunofunctional hydrogels, the ability to quantifiably design hydrogel interfaces described here will improve the sensitivity of hydrogel biosensors, provide a platform to finely screen cell-matrix interactions, and generally enhance the fidelity of micromolded hydrogel features.

15.
Adv Colloid Interface Sci ; 304: 102665, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35468355

ABSTRACT

Biofilms initiate when bacteria encounter and are retained on surfaces. The surface orchestrates biofilm growth through direct physico-chemical and mechanical interactions with different structures on bacterial cells and, in turn, through its influence on cell-cell interactions. Individual cells respond directly to a surface through mechanical or chemical means, initiating "surface sensing" pathways that regulate gene expression, for instance producing extra cellular matrix or altering phenotypes. The surface can also physically direct the evolving colony morphology as cells divide and grow. In either case, the physico-chemistry of the surface influences cells and cell communities through mechanisms that involve additional factors. For instance the numbers of cells arriving on a surface from solution relative to the generation of new cells by division depends on adhesion and transport kinetics, affecting early colony density and composition. Separately, the forces experienced by adhering cells depend on hydrodynamics, gravity, and the relative stiffnesses and viscoelasticity of the cells and substrate materials, affecting mechanosensing pathways. Physical chemistry and surface functionality, along with interfacial mechanics also influence cell-surface friction and control colony morphology, in particular 2D and 3D shape. This review focuses on the current understanding of the mechanisms in which physico-chemical interactions, deriving from surface functionality, impact individual cells and cell community behavior through their coupling with other interfacial processes.


Subject(s)
Bacteria , Biofilms , Bacterial Adhesion/physiology , Cell Membrane , Hydrodynamics
16.
J Hazard Mater ; 435: 128986, 2022 08 05.
Article in English | MEDLINE | ID: mdl-35487002

ABSTRACT

Morphology, the important feature of bloom-forming cyanobacteria, was studied for its impacts on the harmful cyanobacterial bloom (HCB) treatment by coagulative colloidal ozone microbubbles (CCOMBs). The globally-appeared HCB species - Microcystis aeruginosa (spherical cells, block mass colonies), Microcystis panniformis (spherical cells, flat penniform-like colonies) and Anabaena flos-aquae (filamentous morphology) were chosen as representative species. CCOMBs were generated by modifying the bubble surface and the gas core with coagulant and ozone, respectively. The removal of spherical cells and filaments was > 99.5% and ≤ 34.6%, individually, and the latter was ascribed to chain breakage. CCOMBs collected Microcystis panniformis via complexing with the fluorescent and non-fluorescent functional groups of cell colonies but captured Anabaena flos-aquae through the fluorescent ones. More Microcystis aeruginosa got membrane-damaged than Microcystis panniformis; nevertheless, the microcystin-LR (MC-LR) removal was guaranteed through efficiently oxidizing the released MC-LR. Although the outer peptidoglycan sheet of Anabaena flos-aquae was destroyed, the inner cyte membrane remained intact, preventing intracellular MC-LR from releasing. The HCBs dominated by single species with spherical cells were more readily treated than those with co-occurred species. The toxicological tests imply that, as a robust tool for HCB treatment, the CCOMB technology could be eco-environmentally friendly to the aquatic environment.


Subject(s)
Cyanobacteria , Dolichospermum flos-aquae , Microcystis , Ozone , Cyanobacteria/metabolism , Marine Toxins , Microbubbles , Microcystins/metabolism , Microcystins/toxicity , Microcystis/metabolism
17.
Bioact Mater ; 14: 443-455, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35415280

ABSTRACT

The need for bladder reconstruction and side effects of cystoplasty have spawned the demand for the development of alternative material substitutes. Biomaterials such as submucosa of small intestine (SIS) have been widely used as patches for bladder repair, but the outcomes are not fully satisfactory. To capture stem cells in situ has been considered as a promising strategy to speed up the process of re-cellularization and functionalization. In this study, we have developed an anti-CD29 antibody-conjugated SIS scaffold (AC-SIS) which is capable of specifically capturing urine-derived stem cells (USCs) in situ for tissue repair and regeneration. The scaffold has exhibited effective capture capacity and sound biocompatibility. In vivo experiment proved that the AC-SIS scaffold could promote rapid endothelium healing and smooth muscle regeneration. The endogenous stem cell capturing scaffolds has thereby provided a new revenue for developing effective and safer bladder patches.

18.
ACS Appl Mater Interfaces ; 14(16): 18079-18086, 2022 Apr 27.
Article in English | MEDLINE | ID: mdl-35385656

ABSTRACT

Selective isolation of individual target cells from a heterogeneous population is technically challenging; however, the ability to retrieve single cells can have high significance in various aspects of biological research. Here, we present a new photoelectrochemical surface based on a transparent electrode that is compatible with high-resolution fluorescence microscopy for isolating individual rare cells from complex biological samples. This is underpinned by two important factors: (i) careful design of the electrode by patterning discrete Au disks of micron dimension on amorphous silicon-indium tin oxide films and (ii) orthogonal surface chemistry, which modifies the patterned electrode with self-assembly layers of different functionalities, to selectively capture target cells on the Au disks and resist cell binding to the amorphous silicon surface. The co-stimulation of the surface using light from a microscope and an electric potential triggers the reductive desorption of the alkanethiol monolayer from the Au disks to release the single cells of interest from the illuminated regions only. Using circulating tumor cells as a model, we demonstrate the capture of cancer cells on an antibody-coated surface and selective release of single cancer cells with low expression of epithelial cell adhesion molecules.


Subject(s)
Neoplastic Cells, Circulating , Silicon , Electrodes , Epithelial Cell Adhesion Molecule , Humans , Microscopy, Fluorescence
19.
Micromachines (Basel) ; 13(3)2022 Feb 28.
Article in English | MEDLINE | ID: mdl-35334686

ABSTRACT

Circulating tumor cells (CTCs) in cancer patients' peripheral blood have been demonstrated to be a significant biomarker for metastasis detection, disease prognosis, and therapy response. Due to their extremely low concentrations, efficient enrichment and non-destructive release are needed. Herein, an FTO chip modified with multifunctional gelatin nanoparticles (GNPs) was designed for the specific capture and non-destructive release of CTCs. These nanoparticles share a similar dimension with the microvilli and pseudopodium of the cellular surface; thus, they can enhance adhesion to CTCs, and then GNPs can be degraded by the enzyme matrix metalloproteinase (MMP-9), gently releasing the captured cells. In addition, the transparency of the chip makes it possible for fluorescence immunoassay identification in situ under a microscope. Our chip attained a high capture efficiency of 89.27%, a release efficiency of 91.98%, and an excellent cellular viability of 96.91% when the concentration of MMP-9 was 0.2 mg/mL. Moreover, we successfully identified CTCs from cancer patients' blood samples. This simple-to-operate, low-cost chip exhibits great potential for clinical application.

20.
ACS Nano ; 16(1): 211-220, 2022 01 25.
Article in English | MEDLINE | ID: mdl-34559518

ABSTRACT

Current approaches in targeted patient treatments often require the rapid isolation of specific rare target cells. Stream-based dielectrophoresis (DEP) based cell sorters have the limitation that the maximum number of sortable cell types is equivalent to the number of output channels, which makes upscaling to a higher number of different cell types technically challenging. Here, we present a microfluidic platform for selective single-cell sorting that bypasses this limitation. The platform consists of 10 000 nanoliter wells which are placed on top of interdigitated electrodes (IDEs) that facilitate dielectrophoresis-driven capture of cells. By use of a multisectorial design formed by 10 individually addressable IDE structures, our platform can capture a large number of different cell types. The sectorial approach allows for fast and straightforward modification to sort complex samples as different cell types are captured in different sectors and therefore removes the need for individual output channels per cell type. Experimental results obtained with a mixed sample of benign (MCF-10A) and malignant (MDA-MB-231) breast cells showed a target to nontarget sorting accuracy of over 95%. We envision that the high accuracy of our platform, in addition to its versatility and simplicity, will aid clinical environments where reliable sorting of varying complex samples is essential.


Subject(s)
Microfluidic Analytical Techniques , Humans , Electrophoresis/methods , Microfluidic Analytical Techniques/methods , Equipment Design , Cell Separation/methods , Microfluidics
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