Manipulation Of Cells Research Articles

The Coffee Ground for Wound Treatment is Effective, Safe, and Humanized

Coffee water extract strongly inhibits many Gram (+) and Gram (-) bacteria. In experimental wound healing in rats, coffee grounds healed wounds quickly. Its robust antibacterial, antioxidant, and anti-inflammatory perfect for wound healing. The clinical application of coffee grounds for acute and chronic wounds is a safe, compliant, simple, non-allergic, pleasant aroma, and uncomplicated. A thin layer of coffee grounds remains on the wound during replacement to ensure the superficial cells multiply safely and prevent cell manipulation. Debridement and dressing replacement perform rarely. It resulted in practical and faster wound healing and acceptable scarring. The method is called the New Paradigm of wound management. The coffee ground for wounds drives public health strengthening in wound care, promotes patient-centered care, and humanizes humans.

DC-Dielectrophoretic Manipulation and Isolation of Microplastic Particle-Treated Microalgae Cells in Asymmetric-Orifice-Based Microfluidic Chip.

A novel direct-current dielectrophoretic (DC-DEP) method is proposed for the manipulation and isolation of microplastic particle (MP)-treated microalgae cells according to their dielectric properties in a microfluidic chip. The lateral migration and trajectory of the microalgae cells were investigated. To induce stronger DC-DEP effects, a non-homogeneous electric-field gradient was generated by applying the DC electric voltages through triple pairs of asymmetric orifices with three small orifices and one large orifice located on the opposite microchannel wall across the whole channel, leading to the enhanced magnitude of the non-uniform electric-field gradient and effective dielectrophoretic area. The effects of the applied voltage, the polystyrene (PS) adsorption coverage, and thickness on the DC-DEP behaviors and migration were numerically investigated, and it was found that the effect of the PS adsorption thickness of the Chlorella cells on the DC-DEP behaviors can be neglected, but the effect on their trajectory shifts cannot. In this way, the separation of 3 µm and 6 µm Chlorella coated with 100% PS particles and the isolation of the Chlorella cells from those coated with various coverages and thicknesses of PS particles was successfully achieved, providing a promising method for the isolation of microalgae cells and the removal of undesired cells from a target suspension.

A correlation of conductivity medium and bioparticle viability on dielectrophoresis-based biomedical applications.

Dielectrophoresis (DEP) bioparticle research has progressed from micro to nano levels. It has proven to be a promising and powerful cell manipulation method with an accurate, quick, inexpensive, and label-free technique for therapeutic purposes. DEP, an electrokinetic phenomenon, induces particle movement as a result of polarization effects in a nonuniform electrical field. This review focuses on current research in the biomedical field that demonstrates a practical approach to DEP in terms of cell separation, trapping, discrimination, and enrichment under the influence of the conductive medium in correlation with bioparticle viability. The current review aims to provide readers with an in-depth knowledge of the fundamental theory and principles of the DEP technique, which is influenced by conductive medium and to identify and demonstrate the biomedical application areas. The high conductivity of physiological fluids presents obstacles and opportunities, followed by bioparticle viability in an electric field elaborated in detail. Finally, the drawbacks of DEP-based systems and the outlook for the future are addressed. This article will aid in advancing technology by bridging the gap between bioscience and engineering. We hope the insights presented in this review will improve cell suspension medium and promote DEP-viable bioparticle manipulation for health-care diagnostics and therapeutics.

Abstract PR001: Dissecting the role of aging and inflammation on clonal hematopoiesis

Abstract Aging is associated with the appearance in multiple tissues of somatic mutant clones often harboring mutations observed in cancers. In the hematopoietic system this phenomenon is named clonal hematopoiesis of indeterminant potential (CHIP) or “age-related clonal hematopoiesis”. The incidence of CHIP increases exponentially with aging, and has been associated with increased risk of myeloid malignancies, cardiovascular disease, and overall mortality. While mutations are thought to be acquired at a constant rate during life, whether aging plays a role in driving the expansion of these mutant clones is of crucial importance, as it can inform on the potential to prevent or halt the expansion of CHIP clones by intervening with the specific hallmark of aging fueling such expansion. To determine the effect of aging on the expansion of CHIP clones, we have established a method that relies on in vitro manipulation of mouse hematopoietic stem and progenitor cells (HSPC) in order to introduce by CRISPR-Cas9 selected mutations, followed by transplant into young and old recipient mice. Our method has several advantages: i) it allows rapid introduction of the desired mutations from mice of any background, including aged mice, bypassing the need to create transgenic lines; ii) by expanding the cultured cells in previously developed PVA media, it allows efficient engraftment in mildly (busulfan) conditioned recipient mice, avoiding the damaging effects on the bone marrow microenvironment that result from irradiation; iii) by manipulating HSPC with gRNAs targeting either the gene of interest (GFP tagged) or the safe harbor Rosa26 locus (dTomato tagged) prior to pooling, we can assess the competitive advantage of the mutation of interest relative to the Rosa26 control cells and determine their fitness advantage at various time points. We used this technique to generate Dnmt3a and Tet2 mutant clones and tested their expansion in young and aged recipient mice. Our data reveal that Dnmt3a exhibits a relatively mild fitness advantage and no difference in the rate of expansion between young and aged mice. By contrast Tet2-KO HSPC show a significantly faster expansion in old compared to young recipient mice, indicating a greater fitness advantage in the aged background. Tet2 mutant HSPC were previously shown to preferentially expand in inflammatory conditions such as stimulation with microbial products, IL-6 and TNFa. We have preliminary data that shows that co-housing old mice with young syngeneic mice alters their gut microbiome and results in a reduction of inflammation and restoration of more youthful gene expression profiles in stem and progenitor cells in the bone marrow. We are currently testing whether altering the gut microbiome or applying genetic models of reduced inflammation prevents the expansion of Tet2-KO cells, with associated “omics” analyses to explore underlying mechanisms. In all, these studies should contribute to our understanding of the aging-dependent occurrence of CHIP and suggest potential interventions to limit its prevalence. Citation Format: Marco De Dominici, Johannes Menzel, James V. DeGregori. Dissecting the role of aging and inflammation on clonal hematopoiesis [abstract]. In: Proceedings of the AACR Special Conference: Aging and Cancer; 2022 Nov 17-20; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2022;83(2 Suppl_1):Abstract nr PR001.

Microsecond cell triple-sorting enabled by multiple pulse irradiation of femtosecond laser

Femtosecond-laser-assisted cell manipulation, as one of the high throughput cell sorting techniques, is tailored for single-step multiple sorting based on controllable impulsive force. In this paper, femtosecond laser pulses are focused within a pocket structure and they induce an impulse force acting on the flowing objects. The impulsive force is shown to be controllable by a new method to adjust the femtosecond pulse properties. This allows precise streamline manipulation of objects having various physical qualities (e.g., weight and volume). The pulse energy, pulse number, and pulse interval of the femtosecond laser are altered to determine the impulsive force strength. The method is validated in single cell or bead triple-sorting experiments and its capability to perform streamline manipulation in as little as 10 μs is shown. The shift profiles of the beads acting under the impulsive force are studied in order to better understand the sorting mechanism. Additionally, beads and cells with different fluorescence intensities are successfully detected and directed into different microchannels, with maximum success rates of 90% and 64.5%, respectively. To sum up, all results suggest that this method has the potential to sort arbitrary subpopulations by altering the number of femtosecond pulses and that it takes the first step toward developing a single-step multi-selective system.

Trapping of a Single Microparticle Using AC Dielectrophoresis Forces in a Microfluidic Chip.

Precise trap and manipulation of individual cells is a prerequisite for single-cell analysis, which has a wide range of applications in biology, chemistry, medicine, and materials. Herein, a microfluidic trapping system with a 3D electrode based on AC dielectrophoresis (DEP) technology is proposed, which can achieve the precise trapping and release of specific microparticles. The 3D electrode consists of four rectangular stereoscopic electrodes with an acute angle near the trapping chamber. It is made of Ag-PDMS material, and is the same height as the channel, which ensures the uniform DEP force will be received in the whole channel space, ensuring a better trapping effect can be achieved. The numerical simulation was conducted in terms of electrode height, angle, and channel width. Based on the simulation results, an optimal chip structure was obtained. Then, the polystyrene particles with different diameters were used as the samples to verify the effectiveness of the designed trapping system. The findings of this research will contribute to the application of cell trapping and manipulation, as well as single-cell analysis.

A 3D Biocompatible Plasmonic Tweezer for Single Cell Manipulation.

Plasmonic tweezers are an emerging research topic because of their low input power and wide operating range from homogeneous particles to complex biological objects. But it is still challenging for plasmonic tweezers to trap or manipulate objects of tens of microns, especially in biological science. This study introduces a new 3D biocompatible plasmonic tweezer for single living cell manipulation in solution. The key design is a tapered tip whose three-layer surface structure consists of nanoprobe, gold nanofilm, and thermosensitive hydrogel, thiolated poly(N-isopropylacrylamide). Incident light excites the surface plasmon polaritons on gold film and generates heat to induce thermally driven phase transition of the thermosensitive hydrogel, which enables reversible binding between functionalized surface and cell membrane and avoids both thermal and mechanical stresses in the meanwhile. The 3D biocompatible plasmonic tweezer realizes selective capture, 3D pathway free transport, and position-controlled release of target cells, and it displays excellent biocompatibility, low energy consumption, and high operational flexibility.

Acousto-dielectric tweezers for size-insensitive manipulation and biophysical characterization of single cells

The intrinsic biophysical properties of cells, such as mechanical, acoustic, and electrical properties, are valuable indicators of a cell’s function and state. However, traditional single-cell biophysical characterization methods are hindered by limited measurable properties, time-consuming procedures, and complex system setups. This study presents acousto-dielectric tweezers that leverage the balance between controllable acoustophoretic and dielectrophoretic forces applied on cells through surface acoustic waves and alternating current electric fields, respectively. Particularly, the balanced acoustophoretic and dielectrophoretic forces can trap cells at equilibrium positions independent of the cell size to differentiate between various cell-intrinsic mechanical, acoustic, and electrical properties. Experimental results show our mechanism has the potential for applications in single-cell analysis, size-insensitive cell separation, and cell phenotyping, which are all primarily based on cells’ intrinsic biophysical properties. Our results also show the measured equilibrium position of a cell can inversely determine multiple biophysical properties, including membrane capacitance, cytoplasm conductivity, and acoustic contrast factor. With these features, our acousto-dielectric tweezing mechanism is a valuable addition to the resources available for biophysical property-based biological and medical research.

Dynamic DNA Nanostructures for Cell Manipulation.

Dynamic DNA nanostructures are DNA nanostructures with reconfigurable elements that can undergo structural transformations in response to specific stimuli. Thus, anchoring dynamic DNA nanostructures on cell membranes is an attractive and promising strategy for well-controlled cell manipulation. Here, we review the latest progress in dynamic DNA nanostructures for cell manipulation. Commonly used mechanisms for dynamic DNA nanostructures are first introduced. Subsequently, we summarize the anchoring strategies for dynamic DNA nanostructures on cell membranes and list possible applications (including programming cell membrane receptors, controlling ligand activity and drug delivery, capturing and releasing cells, and assembling cells into clusters). Finally, insights into the remaining challenges are presented.

Combining lipid-mimicking-enabled transition metal and enzyme-mediated catalysis at the cell surface of E. coli.

Being an essential multifunctional platform and interface to the extracellular environment, the cell membrane constitutes a valuable target for the modification and manipulation of cells and cellular behavior, as well as for the implementation of artificial, new-to-nature functionality. While bacterial cell surface functionalization via expression and presentation of recombinant proteins has extensively been applied, the corresponding application of functionalizable lipid mimetics has only rarely been reported. Herein, we describe an approach to equip E. coli cells with a lipid-mimicking, readily membrane-integrating imidazolium salt and a corresponding NHC-palladium complex that allows for flexible bacterial membrane surface functionalization and enables E. coli cells to perform cleavage of propargyl ethers present in the surrounding cell medium. We show that this approach can be combined with already established on-surface functionalization, such as bacterial surface display of enzymes, i.e. laccases, leading to a new type of cascade reaction. Overall, we envision the herein presented proof-of-concept studies to lay the foundation for a multifunctional toolbox that allows flexible and broadly applicable functionalization of bacterial membranes.

Cell Manipulation and Neuron Regulation Based on Tapered Optical Fiber Tweezers

Cell Manipulation and Neuron Regulation Based on Tapered Optical Fiber Tweezers

Acoustic manipulation of microparticles using a two-dimensional phononic crystal plate

Acoustic waves can manipulate particles without contact or damage, and has received increasing attention due to their potential applications in various fields, such as cell sorting, organoid construction, and material assembly. In general, high-throughput manipulation of microparticles relies on a large number of active transducers and phase-shifting circuits to create standing wave patterns, thus significantly inducing system complexity. Recently, we realized the parallel manipulation of microparticles by using an acoustic field modulated by a one-dimensional phononic crystal plate. The concept is based on the fact that phononic crystal plate can resonantly excite the zero-order asymmetric (<i>A</i><sub>0</sub>) Lamb wave, inducing highly localized periodic radiation force on the particles. In this paper, we further show that by using a two-dimensional phononic crystal plate (TDPCP), parallel manipulation of massive particles can be achieved only with a single transducer. The <i>A</i><sub>0</sub> Lamb wave can be excited by a TDPCP, forming a two-dimensional periodic localized field, and then particles can suffer negative vertical force and stable zero horizontal force, inducing two-dimensional periodic trapping on the surface of the plate. Combining a PZT source with a TDPCP consisting of a brass plate patterned with periodical brass stubs, we observe the capture and arrangement of glass microspheres, achieving two-dimensional arrangement manipulation of particles on the TDPCP. This system represents a significant advancement in developing high-throughput, rapid, and flexible devices for particles and cell manipulation.

Acoustic radiation force of elastic spherical shell with eccentric droplet in plane wave acoustic field

Based on the application of acoustic waves in cell manipulation, a model consisting of an elastic spherical shell and eccentric droplet is established to simulate a eukaryotic cell and analyze the acoustic radiation force (ARF) on the cell. In this work, we derive an exact expression for the ARF on the liquid-filled spherical shell. The influence of eccentric distance, radius of the eccentric droplet and impedance of the medium inside the liquid-filled spherical shell on the ARF are analyzed numerically. The results show that the ARF is very sensitive to the position and size of the eccentric droplet. As the eccentricity of the eccentric droplet increases, the ARF becomes greater. In a low frequency region (<i>ka</i><3) the resonance peak point increases, and the position of the curve ventral point shifts to the high frequency region (<i>ka</i>>3) with the increase of the radius of the eccentric droplet. The effect of the position variation on the ARF is more significant than that of the radius change, and both of their effects will be superimposed on each other. The ARF, as a function of <i>ka,</i> is mainly affected by the variation of the nucleus characteristic impedance. The ARF amplitude around <i>ka</i> = 5 increases and the position of the ventral point tends to shift rightwards with the enlargement of the nucleus impedance. Therefore, the radiation response at a certain frequency or in a cell size range can be enhanced when the nucleus impedance increases. The results of this study provide theoretical basis for the cell sorting and targeted therapy.

Precise Aspiration and Positioning Control Based on Dynamic Model Inside and Outside the Micropipette

Cell aspiration is a common technique in cell manipulation for cell transfer or intracellular property measurement. In this paper, we present a robotic micromanipulation system for cell aspiration and positioning by a micropipette. Considering the relative motion of the object and the fluid, we first establish an overall dynamic model of microbead motion inside and outside the micropipette based on computational fluid dynamics (CFD). Then we design an adaptive sliding mode controller (ASMC) for microbead aspiration outside the micropipette and positioning inside the pipette based on the dynamic model. The controller is proven to achieve asymptotic stability by Lyapunov techniques. Simulation and experimental results demonstrate the effectiveness of the fluid model and the performance of the designed control system. Note to Practitioners—Cell aspiration with a micropipette is a key technology in cell manipulation. Generally, there is relative motion between the aspirated object and the fluid, resulting in large overshoot even aspiration failure. In this paper, we set up an overall dynamic model of microbead motion inside and outside the micropipette, combining microbead motion dynamics, fluid dynamics and pneumatic pump modeling. Based on this model, we design an ASMC for microbead aspiration outside the micropipette and positioning inside the pipette. In simulations and experiments, the positioning errors of the microbead of different sizes converge to zero without overshoot, revealing the strong robustness of the controller. Applications for this technology include cell or sperm aspiration and injection.

Bisymmetric coherent acoustic tweezers based on modulation of surface acoustic waves for dynamic and reconfigurable cluster manipulation of particles and cells.

Acoustic tweezers based on surface acoustic waves (SAWs) have raised great interest in the fields of tissue engineering, targeted therapy, and drug delivery. Generally, the complex structure and array layout design of interdigital electrodes would restrict the applications of acoustic tweezers. Here, we present a novel approach by using bisymmetric coherent acoustic tweezers to modulate the shape of acoustic pressure fields with high flexibility and accuracy. Experimental tests were conducted to perform the precise, contactless, and biocompatible cluster manipulation of polystyrene microparticles and yeast cells. Stripe, dot, quadratic lattice, hexagonal lattice, interleaved stripe, oblique stripe, and many other complex arrays were achieved by real-time modulation of amplitudes and phase relations of coherent SAWs to demonstrate the capability of the device for the cluster manipulation of particles and cells. Furthermore, rapid switching among various arrays, shape regulation, geometric parameter modulation of array units, and directional translation of microparticles and cells were implemented. This study demonstrated a favorable technique for flexible and versatile manipulation and patterning of cells and biomolecules, and it has the advantages of high manipulation accuracy and adjustability, thus it is expected to be utilized in the fields of targeted cellular assembly, biological 3D printing, and targeted release of drugs.

Single-Fiber Optical Tweezer Based on Coexistence of LP01 and LP11 Modes for Multiplexed Capture and Manipulation of Biological Cells

Single-Fiber Optical Tweezer Based on Coexistence of LP01 and LP11 Modes for Multiplexed Capture and Manipulation of Biological Cells

Investigating influences of intravenous fluids on HUVEC and U937 monocyte cell lines using the magnetic levitation method.

Intravenous fluids are being widely used in patients of all ages for preventing or treating dehydration in the intensive care units, surgeries in the operation rooms, or administering chemotherapeutic drugs at hospitals. Dextrose, Ringer, and NaCl solutions are widely received as intravenous fluids by hospitalized patients. Despite their widespread administration for over 100 years, studies on their influences on different cell types have been very limited. Increasing evidence suggests that treatment outcomes might be altered by the choice of the administered intravenous fluids. In this study, we investigated the influences of intravenous fluids on human endothelial (HUVEC) and monocyte (U937) cell lines using the magnetic levitation technique. Our magnetic levitation platform provides label-free manipulation of single cells without altering their phenotypic or genetic properties. It allows for monitoring and quantifying behavior of single cells by measuring their levitation heights, deformation indices, and areas. Our results indicate that HUVEC and U937 cell lines respond differently to different intravenous fluids. Dextrose solution decreased the viability of both cell lines while increasing the heterogeneity of areas, deformation, and levitation heights of HUVEC cells. We strongly believe that improved outcomes can be achieved when the influences of intravenous fluids on different cell types are revealed using robust, label-free, and efficient methods.

Illustrative Potency Assay Examples from Approved Therapies.

Advanced therapy medicinal products (ATMP) encompass a new type of drugs resulting from the manipulation of genes, cells, and tissues to generate innovative medicinal entities with tailored pharmaceutical activity. Definition of suitable potency tests for product release are challenging in this context, in which the active ingredient is composed of living cells and the mechanism of action often is poorly understood. In this chapter, we present and discuss actual potency assays used for the release of representative commercial ATMP from each category of products (namely, KYMRIAH® (tisagenlecleucel), Holoclar® (limbal epithelial stem cells), and PROCHYMAL®/RYONCIL™ (remestemcel-L)). We also examine concerns related to the biological relevance of selected potency assays and challenges ahead for harmonization and broader implementation in compliance with current quality standards and regulatory guidelines.

Viral Transduction of Mammalian Spermatogonial Stem Cells.

Lentiviral vectors have been major tools for genetic manipulation of spermatogonial stem cells (SSCs) in vitro. Adeno-associated viral vectors are promising emerging tools for in vivo SSC transduction that are less invasive, compared to lentivirus, since AAV DNA is not integrated into the host genome and the host genome remains intact. In this chapter, we describe protocols using lentiviral and adeno-associated viral vectors to transduce SSCs in vitro and vivo, respectively.

Assessment Of Effects of Manipulation of Stem Cell Conditioning Media with Ethyl Gallate in Regenerative Strategies

Assessment Of Effects of Manipulation of Stem Cell Conditioning Media with Ethyl Gallate in Regenerative Strategies