Biological Cells Research Articles

Effects of Static and Low-Frequency Magnetic Fields on Gene Expression.

Substantial research over the past two decades has established that magnetic fields affect fundamental cellular processes, including gene expression. However, since biological cells and subcellular components exhibit diamagnetic behavior and are therefore subjected to very small magnetic forces that cannot directly compete with the viscoelastic and bioelectric intracellular forces responsible for cellular machinery functions, it becomes challenging to understand cell-magnetic field interactions and to reveal the mechanisms through which these interactions differentially influence gene expression in cells. The limited understanding of the molecular mechanisms underlying biomagnetic effects has hindered progress in developing effective therapeutic applications of magnetic fields. This review examines the expanding body of literature on genetic events during static and low-frequency magnetic field exposure, focusing particularly on how changes in gene expression interact with cellular machinery. To address this, we conducted a systematic review utilizing extensive search strategies across multiple databases. We explore the intracellular mechanisms through which transcription functions may be modified by a magnetic field in contexts where other cellular signaling pathways are also activated by the field. This review summarizes key findings in the field, outlines the connections between magnetic fields and gene expression changes, identifies critical gaps in current knowledge, and proposes directions for future research. LEVEL OF EVIDENCE: NA TECHNICAL EFFICACY: Stage 4.

Emergence of Fluorescent Glycodots for Biomedical Applications.

Carbohydrate-functionalized quantum dots exhibit excellent physical characteristics and enhance the steric interaction with biological cells and tissues. Glycoconjugation of quantum dots promotes aqueous solubility, stability, and reduced immunogenicity. Carbohydrate-protein interactions are involved in various vital processes and provide insight into cellular recognition, cell-to-cell communication, pathogenicity, antigen-antibody recognition, and enzymatic action. Quantum dots are fluorescent materials with rich quantum mechanical and unique optical properties, making them valuable for biomedical applications. Recent advancements in quantum dot materials as biomedical tools have led to the development of carbohydrate-conjugated glyco-functionalized quantum dots. These innovations promise application as nanocarriers, imaging agents, fluorescent probes, and theranostics. This review provides an overview of glyco nanotechnology, emphasizing carbohydrate-conjugated metal-, silicon-, and carbon-based quantum dots as glyco dots and their potential biomedical uses. We hope that this study will address the gap in this field and provide a more precise understanding of the subject.

Toward low-noise on-chip plasmonic three-dimensional biological cell imaging

Enhancing accessibility to affordable and efficient cell imaging tools has been a longstanding worldwide objective for rapid disease detection and diagnosis. We present an innovative approach to this goal, introducing a compact, portable, and user-friendly three-dimensional (3D) cell imaging platform leveraging silicon photonics and the surface plasmon coupled emission (SPCE) phenomenon. Central to our method is a specially designed slide that incorporates a fundamental SPCE structure seamlessly integrated with a silicon nitride (SiN) waveguide. We introduce a grooved array on the slide to couple light into the waveguide, interfacing with a broadband light source. This source is employed to excite fluorescently labeled cells. The excitation is achieved using edge coupling through the SiN waveguide, directing the excitation light to the specimen placed on the SPCE platform. This integrated architecture eliminates the necessity for an additional filter to extract the required light for fluorophore excitation while enabling precise excitation of labeled cells. Following the fluorophore excitation, the emitted SPCE signals are captured and subjected to analysis. We have developed an imaging algorithm based on the emitted light patterns, which we comprehensively detail through theoretical demonstration. This algorithm has the remarkable capability of achieving 3D cell imaging. This fusion of optics and computational techniques can significantly impact the domain of cell imaging by enabling the development of easily accessible and portable point-of-care (POC) imaging tools.

A low-cost printed circuit board-based centrifugal microfluidic platform for dielectrophoresis

In recent decades, electrokinetic handling of microparticles and biological cells found many applications ranging from biomedical diagnostics to microscale assembly. The integration of electrokinetic handling such as dielectrophoresis (DEP) greatly benefits microfluidic point-of-care systems as many modern assays require cell handling. Compared to traditional pump-driven microfluidics, typically used for DEP applications, centrifugal CD microfluidics provides the ability to consolidate various liquid handling tasks in self-contained discs under the control of a single motor. Therefore, it has significant advantages in terms of cost and reliability. However, to integrate DEP on a spinning disc, a major obstacle is transferring power to the electrodes that generate DEP forces. Existing solutions for power transfer lack portability and availability or introduce excessive complexity for DEP settings. We present a concept that leverages the compatibility of DEP and inductive power transfer to bring DEP onto a rotating disc without much circuitry. Our solution leverages the ongoing advances in the printed circuit board market to make low-cost cartridges (<$1) that can employ DEP, which was validated using yeast cells. The resulting DEPDisc platform solves the challenge that existing printed circuit board electrodes are reliant on expensive high-voltage function generators by boosting the voltage using resonant inductive power transfer. This work includes a device costing less than $100 and easily replicable with the information provided in the Supplementary material. Consequently, with DEPDisc we present the first DEP-based low-cost platform for cell handling where both the device and the cartridges are truly inexpensive.

Artificial cells with all-aqueous droplet-in-droplet structures for spatially separated transcription and translation

The design of functional artificial cells involves compartmentalizing biochemical processes to mimic cellular organization. To emulate the complex chemical systems in biological cells, it is necessary to incorporate an increasing number of cellular functions into single compartments. Artificial organelles that spatially segregate reactions inside artificial cells will be beneficial in this context by rectifying biochemical pathways. Here, we develop artificial cells with all-aqueous droplet-in-droplet structures that separate transcription and translation processes like the nucleus and cytosol in eukaryotic cells. This architecture uses protein-based inner droplets and aqueous two-phase outer compartments, stabilized by colloidal emulsifiers. The inner droplet is designed to enrich DNA and RNA polymerase for transcription, coupled to translation at the outer droplet via mRNA-mediated cascade reactions. We show that these processes proceed independently within each compartment, maintaining genotype-phenotype correspondence. This approach provides a practical tool for exploring complex systems of artificial organelles within large ensembles of artificial cells.

Identification and expression analysis of P-type ATPase IIIA subfamily in Puccinia Striiformis f. sp. tritici

BackgroundPuccinia striiformis f. sp. tritici (Pst) causes wheat stripe (yellow) rust disease, which is one of the most destructive diseases affecting wheat worldwide. ATPases, a class of membrane proteins, play an important role in material exchange and signal transduction both within and outside biological cells by transporting ions and phospholipids. In plant pathogens, P-type ATPases primarily participate in pathogen development and virulence regulation. However, the P-type ATPase of subfamily IIIA (PMA) has not yet been identified in Pst. To investigate the potential functions of the PMA gene family in Pst, we conducted a genome-wide bioinformatics analysis and examined the expression profiles of the PMA gene family.ResultsSix PMA genes were identified in the genome of P. striiformis f. sp. tritici (CYR34 race). The PMA proteins encoded by these genes ranged in length from 811 to 960 amino acids (aa). Each of the six PMA genes contained a typical ATPase IIIA H superfamily domain and was distributed across four chromosomes. Thirty-six major cis-regulatory elements were detected within the PMA gene family members. Elements such as the CGTCA-motif and TGACG-motif play significant roles in responding to environmental stresses and hormone signals. Quantitative PCR analysis revealed that the expression of the PMA04 gene was generally higher at 9 °C under various temperature stresses. The PMA06 gene typically exhibited higher expression levels at 16 °C. During the infection of Pst, the expression levels of PMA04, PMA05, and PMA06 were elevated at 72 h post treatment.ConclusionsOur results indicate that the PMA gene family in the CYR34 strain comprises six PMA genes, which are crucial for managing temperature stress and pathogen infection, and exhibit a distinctive splicing pattern. This study not only identifies a target and direction for the development of new, efficient, and environmentally friendly control agents for wheat stripe rust but also establishes a foundation for analyzing its pathogenic mechanisms.

Multifaceted roles of insulin‑like growth factor 2 mRNA binding protein 2 in human cancer (Review).

Insulin‑like growth factor 2 mRNA binding protein 2 (IGF2BP2) is an RNA binding protein that functions as an N6‑methyladenosine reader. It regulates various biological processes in human cancers by affecting the stability and expression of target RNA transcripts, including coding RNAs and non‑coding RNAs (ncRNAs). Numerous studies have shown that IGF2BP2 expression is aberrantly increased in various types of cancer and plays multifaceted roles in the development and progression of human cancers. In the present review, the clinical importance of IGF2BP2 is summarized and its involvement in the regulation of biological processes, including proliferation, metastasis, chemoresistance, metabolism, tumor immunity, stemness and cell death, in human cancers is discussed. The chemical compounds that have been developed as IGF2BP2 inhibitors are also detailed. As ncRNAs are now important potential therapeutic agents for cancer treatment, the microRNAs that have been reported to directly target and inhibit IGF2BP2 expression in cancers are also described. In summary, by reviewing the latest literature, the present study aimed to highlight the clinical importance and physiological functions of IGF2BP2 in human cancer, with a focus on the great potential of IGF2BP2 as a target for inhibitor development. The present review may inspire new ideas for future studies on IGF2BP2, which may serve as a specific therapeutic target in cancer.

True cancer stem cells exhibit relative degrees of dormancy and genomic stability.

Cancer stem cells in human tumors have been defined by stem cell markers, embryonal signaling pathways and characteristic biology, ie., namely the ability to repopulate the proliferating population. However, even if these properties can be demonstrated within a tumor cell subpopulation, it does not mean that they are truly hierarchical stem cells because they could have been derived from the proliferating population in a reversible manner. Using a human PDX, Mary-X, that overall expressed a strong cancer stem cell phenotype, the study conducted both GPP-labelled retroviral transfection and fluorescent microsphere uptake studies to distinguish proliferating from dormant cells and array CGH to identify regions of amplifications (gains) and deletions (losses) on the overall Mary-X population and then applied derived probes by FISH on individual cells to identify a genomically stable subpopulation. Whereas 97-99 % of the cells expressed retroviral GFP and not fluorescent particles and showed numerous gene amplifications and deletions, approximately 1-3 % of the cells showed the opposite. The subpopulation with the retained fluorescent microspheres and exhibiting genomic stability was significantly smaller in size than their GFP-expressing and genomically unstable counterparts. Sorting Mary-X spheroids on the basis of either CD133 or ALDH positivity further enriched for this subpopulation. These studies indicate that a truly biological cancer stem cell subpopulation exists that exhibits both dormancy and genomic stability. This subpopulation could not have been derived from the proliferating and resulting genomically unstable population and therefore represents a truly hierarchical stem cell subpopulation capable of only unidirectional differentiation.

P0038 Perianal Fistula Closure after Heterologous Mesenchymal Stem Cell Injections is Associated with Protein Levels indicating Lower Tissue Immune Infiltrate, Specific Proteins Involved in the Control of Apoptosis, and Probable Higher Tissues Remodeling and Proteasome Activity

Abstract Background Perianal fistulae affects 30-34% of patients with Crohn’s Disease (CD)[1]. Scarce evidences are available on the perianal fistula pathophysiology. Bone marrow-derived Mesenchymal Stem Cells (bmMSCs) local injections have been found safe and efficient for 50% of CD patients included in a previous prospective monocentric study[2]. The present study aims at identifying potential proteins associated with fistulae closure following bmMSCs local injection, using the biological material collected during fistula tract curettage Methods In the prospective interventional uncontrolled study carried out at CHU of Liège (2019 - 2021), 16 CD have been treated and 10 curettage samples have been analyzed by label free proteomics using mass spectrometry technology[3]. Differential analysis comparing responders (R) with perianal fistula closure at W48 (n=5) with non-responders (NR), with absence of closure at any visit including W48, (n=5), identified specific proteomic profile changes, which were also evaluated by Gene Ontology analyses to identify biological processes, cell types and pathways associated with fistula closure. Results total of 1883 proteins were identified and the differential analysis revealed 48 proteins differentially distributed in R versus NR profiles. Only 18 were more abundant in R, among which the product of the STK4, PLP2, CYB5B and FLG genes, showing the strongest significant increases in R and therefore potential associations with fistula closure after bmMSCs injections. The fistula tract material of patients showing no closure (NR) reveal higher number of proteins, together with NR&amp;gt;R relative abundances, associated with inflammatory and immune infiltrates, with chemokines, bacterial invasion. NR profiles show as well lower numbers and relative levels of proteins involved in wound healing and in matrix remodeling than in R (figures 1 and 2). Among the proteins, differentially distributed in R versus NR, specific pro-apoptotic (R&amp;gt;NR) and anti-apoptotic proteins (NR&amp;gt;R) could be highlighted, in addition to specific proteins acting upstream pathways involved in morphogenesis, carcinogenesis and fibrosis (HIPPO, MAPK, JAK-STAT pathways and TGF signaling). Conclusion Our data provide the first descriptive picture of proteins and likely process/pathways associated with fistula closure after bmMSCs treatment. While independent confirmations are required these preliminary results suggest that the apoptotic process, cell infiltrate degree and proteins involved in tissue remodelling and wound healing, already impacted in fistulae tracts before the bmMSCs injections might be important factors associated with fistula closure outcome in this trial.

Global alignment and local curvature of microtubules in mouse fibroblasts are robust against perturbations of vimentin and actin.

The eukaryotic cytoskeleton is an intricate network of three types of mechanically distinct biopolymers - actin filaments, microtubules and intermediate filaments (IFs). These filamentous networks determine essential cellular functions and properties. Among them, microtubules are important for intracellular transport and establishing cell polarity during migration. Despite their intrinsic stiffness, they exhibit characteristic bending and buckling in cells due to nonthermal forces acting on them. Interactions between cytoskeletal filaments have been found but are complex and diverse with respect to their effect on the mechanical behavior of the filaments and the architecture of networks. We systematically study how actin and vimentin IFs influence the network structure and local bending of microtubules by analyzing fluorescence microscopy images of mouse fibroblasts on protein micropatterns. Our automated analysis averages over large amounts of data to mitigate the effect of the considerable natural variance in biological cell data. We find that the radial orientation of microtubules in circular cells is robust and is established independently of vimentin and actin networks. Observing the local curvature of microtubules, we find highly similar average bending of microtubules in the entire cell regardless of the cytoskeletal surrounding. Small systematic differences cannot be attributed directly to vimentin and actin densities. Our results suggest that, on average, microtubules in unpolarized mouse fibroblasts are unexpectedly independent of the rest of the cytoskeleton in their global network structure and their local curvature.

Field switching of microfabricated metamagnetic FeRh MRI contrast agents

In a step towards generating switchable MRI cellular labels, we demonstrate in-situ field switching of micron scale metamagnetic Iron-Rhodium (FeRh) thin film particles. A thin-film (200 nm) FeRh sample was fabricated and patterned into an array of progressively smaller squares with sizes ranging from 500 μm down to 1 μm. The large first order phase change from antiferromagnetic to ferromagnetic state was characterized using vibrating sample magnetometry, magnetic force microscopy, and MRI. Room temperature MRI experiments sensitive to the local magnetic field surrounding the particles demonstrated the low moment state (OFF MRI contrast) at 4.7T and high moment state (ON MRI contrast) at 11.7T for the array where sizes down to 2–3 μm were observed in MRI at 50 μm resolution. The expected temperature dependent MRI contrast change was seen at 4.7T, where 10 μm particles could be observed at 150 μm resolution in the ON state. A shielded MRI insert, used to temporarily increase or decrease the magnetic field up to 0.77T amplitude, was used to reversibly switch the particle array at constant temperature and blink the particles ON and OFF at 4.7T. This work demonstrates the MRI contrast switching potential for FeRh particles with biological cell dimensions, and the use of magnetic field pulses for reversible MRI label contrast control.

Huaier inhibits the proliferation and migration of gastrointestinal stromal tumors by regulating the JAK2 / STAT3 signaling pathway.

Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor of the digestive tract, often accompanied by a high risk of recurrence and drug resistance. Huaier (Trametes robiniophila Murr), a traditional Chinese medicinal fungus, has demonstrated potent anticancer properties and is widely used as an adjuvant treatment for liver, breast, gastric, colon, and non-small cell lung cancers. However, its effects and molecular mechanisms in GIST remain unclear. This study aims to explore the inhibitory effects and underlying mechanisms of Huaier on GIST through network pharmacology and experimental validation. Initially, we utilized a publicly accessible database to identify the core targets and principal pathways associated with Huaier's therapeutic effects on gastrointestinal stromal tumors. To further evaluate its biological impact, cell viability, proliferation, migration, and invasion were assessed through CCK-8 and EdU assays, wound healing tests, and Transwell experiments. Apoptotic cell death was quantified using flow cytometry analysis. Additionally, the influence of Huaier extract on the expression levels of JAK2 and STAT3 proteins was examined via Western blotting. Finally, a subcutaneous xenograft mouse model was employed to investigate the anti-tumor efficacy of Huaier in vivo. In this study, GAPDH, TNF, STAT3, ESR1, EGFR, IL6, CCND1, PTGS2, BCL2L1, and MAPK3 were identified as shared molecular targets, with the JAK/STAT signaling pathway recognized as the pivotal regulatory mechanism. Experimental findings demonstrated that Huaier exerted inhibitory effects on the proliferation, migration, and invasion of GIST-T1 and GIST-882 cells, exhibiting both dose- and time-dependent responses. Furthermore, Huaier was found to promote apoptosis in these cells. Western blot analysis revealed that treatment with Huaier extract significantly decreased the phosphorylation levels of JAK2 and STAT3, thereby suppressing the activation of the JAK2 / STAT3 signaling cascade. In vivo experiments further substantiated these findings, showing that Huaier treatment markedly reduced tumor size and inhibited tumor progression. Our results suggest that Huaier may inhibit the growth of GIST cells by inhibiting the JAK2/STAT3 signaling pathway, reduce cell proliferation, induce apoptosis, reduce cell migration and invasion, and show anti-tumor effects in vivo and in vitro.

Analysis of the contractile work of a single cardiomyocyte by atomic force microscopy.

Atomic force microscopy (AFM) is widely used for the imaging and characterization of biological cells because of its nanoscale spatial resolution and force resolution. However, in the previous studies, the inability to effectively detect the contractile work of cardiomyocytes and the 3D dynamic expressions of their contraction and relaxation behaviors posed significant challenges. Therefore, this work presents a method for the analysis of the contractile work of a single cardiomyocyte by AFM. Two different contractile work measurement modes of cardiomyocytes are proposed, which are the constant height contact mode and the constant force contact mode. The differences in the contractile work were analyzed in two measurement modes. The changes in the contractile work of a single cardiomyocyte in the two measurement modes were studied, and the accuracies of the two measuring models were verified using ginseng extract. After the action of drugs, the contraction force of cardiomyocytes and the work done by contraction force increased. The experimental results indicated that the detection results of the ginseng water extract acting on the same cardiomyocyte by nanomanipulation technology were consistent with its pharmacological effects. Thus, it is reliable to detect the mechanical properties of cardiomyocytes using the nanomanipulation system. This study provides a new method for measuring the contraction force and contractile work of a single cardiomyocyte.

Developing predictive models for tocilizumab response in rheumatoid arthritis: a gene expression and machine learning approaches

Background: Rheumatoid arthritis (RA) is a chronic autoimmune disease treated with tocilizumab in patients unresponsive to methotrexate. This study aimed to identify gene expression profiles and predictive models for tocilizumab treatment response in RA patients. Methods: Using the GSE78068 dataset from 38 RA patients, we identified differentially expressed genes between remission and non-remission groups. Predictive models were created using CART, random forest, and SVM techniques, with model genes selected through LASSO regression. Gene set enrichment and immune cell landscape analyses were performed to understand biological pathways and immune cell composition. Results: Analysis revealed 40 differentially expressed genes, with LASSO regression identifying 8 model genes significantly associated with remission. The SVM-based model achieved the highest performance (AUC=1.0, Brier score=0.025). Conclusions: This study developed an effective 8-gene model for predicting tocilizumab treatment response, potentially supporting personalized therapy in RA patients.

Engineered Cell Microenvironments: A Benchmark Tool for Radiobiology.

The development of engineered cell microenvironments for fundamental cell mechanobiology, in vitro disease modeling, and tissue engineering applications increased exponentially during the last two decades. In such context, in vitro radiobiology is a field of research aiming at understanding the effects of ionizing radiation (e.g., X-rays/photons, high-speed electrons, and high-speed protons) on biological (cancerous) tissues and cells, in particular in terms of DNA damage leading to cell death. Herein, the perspective provides a comparative assessment overview of scaffold-free, scaffold-based, and organ-on-a-chip models for radiobiology, highlighting opportunities, limitations, and future pathways to improve the currently existing approaches toward personalized cancer medicine.

Integrated Biosensor with Microfluidic Chip and Microwave Sensor Chip for Cell Separation and Detection

AbstractIn this work, an integrated biosensor consisting of spiral microfluidic array and microwave sensors is proposed for simultaneous separation and detection of cells. The biosensor integrated by plasma processing technology is fabricated by soft lithography and glass‐based IC process, which has the advantages of simple preparation, low cost, and reliable structure. In the field of clinical medicine, Escherichia coli (E. coli) is the causative agent of urinary tract infections, which leads to an increase in the number of white blood cells (WBCs) present in the urine. Different concentrations of E. coli and WBCs mixed solution are configured to perform biological cell experiments and the capability of the biosensor in separating and detecting WBCs is verified. Interdigital capacitors (IDCs) and split ring resonators (SRRs) are employed to detect the WBCs obtained by microfluidic array separation. The microfluidic array exhibits a WBC collection rate of 92.7%. The capacitance of the IDC and the resonant amplitude of the SRR exhibit a decrease of 51.36 pF and 0.34 dB, which demonstrates a satisfactory linearity of 0.96 and 0.98, respectively. Consequently, the integrated biosensor used to simultaneously separate and detect WBCs has the potential for the early diagnosis of urinary tract infections in clinical medicine.

Dynamically reconfigurable acoustofluidic metasurface for subwavelength particle manipulation and assembly

Particle manipulation plays a pivotal role in scientific and technological domains such as materials science, physics, and the life sciences. Here, we present a dynamically reconfigurable acoustofluidic metasurface that enables precise trapping and positioning of microscale particles in fluidic environments. By harnessing acoustic-structure interaction in a passive membrane resonator array, we generate localized standing acoustic waves that can be reconfigured in real-time. The resulting radiation force allows for subwavelength manipulation and patterning of particles on the metasurface at individual and collective scales, with actuation frequencies below 2 MHz. We further demonstrate the capabilities of the reconfigurable metasurface in trapping and enriching beads and biological cells flowing in microfluidic channels, showcasing its potential in high-throughput bioanalytical applications. Our versatile and biocompatible particle manipulation platform is suitable for applications ranging from the assembly of colloidal particles to enrichment of rare cells.

Measurement of resistivity of biofluids in the presence of an electrical double layer

Abstract Detecting alterations in the electrical response of human biofluids can provide valuable information in the early stages on pathological conditions in a patient. Developing techniques for obtaining rapid information on the electrical resistivity of common ionic biofluids by non-invasive techniques can improve medicare through a rapid and more precise diagnosis. In this work, we analyze the use of an electrical device consisting of a cell formed of flat parallel steel plates to measure the resistivity of these substances. When the electrical cell is filled with a biofluid an electrical double layer (EDL) is formed on the electrodes/biofluid interface. Then, we measure the electrical response and examine the general conditions under which the EDL does not interfere with the assesment of the biofluid’s resistivity. The electrical response is analyzed in terms of an equivalent circuit model. Also, a simplified theoretical model of a suspension of biological cells considering spherical particles with a membrane is discussed to validate measurements and theoretically exhibit the contribution of the cell’s membrane to the effective resistivity. We present measurements of the resistance of the electrical cell filled with electrolyte solutions, blood plasma, and diluted suspensions of erythrocytes in a hypotonic solution. Results show that the resistance of the electrical cell is sensitive to the volume density of biological cells suspended between the parallel plate electrodes, producing a signal with a high signal to noise ratio. From the measured resistance of a suspension of erythrocytes in a isotoinc solution and the simplified theoretical model, we estimate the value of the conductivity of the interior of the erythrocytes. The results show that measured resistance varies with blood samples and hemolysis progression. The device's sensitivity to the number of erythrocytes passing between the electrodes makes it useful for measuring sedimentation kinetics.

Molecular-Scale Simulation of Wetting of Actin Filaments by Protein Droplets.

Liquid phase-separating proteins can form condensates that play an important role in spatial and temporal organization of biological cells. The understanding of the mechanisms that lead to the formation of protein condensates and their interactions with other biomolecules may lead to processing routes for soft materials with tailored geometry and function. Fused in sarcoma (FUS) is an example of a nuclear protein that forms stable complexes, and recent studies have highlighted its ability to wet actin filaments and bundle them into networks. We perform coarse-grained molecular dynamics simulations to investigate the wetting and spreading of FUS droplets on actin filaments. We employ the Martini model and rescale the protein-protein and protein-actin interactions to tune the interfacial and wetting properties of FUS droplets. By measuring the molecular displacements in the three-phase region, we are able to relate contact angle, contact line velocity, and contact line friction in terms of a linear approximation of molecular kinetic theory. The results show that the rescaled Martini model can be used to study the molecular mechanisms of dynamic wetting at the nanoscale and to obtain quantitative predictions of the contact line friction and contact angles during dynamic wetting.

Functional Hydrogel Interfaces for Cartilage and Bone Regeneration.

Effective treatment of bone diseases is quite tricky due to the unique nature of bone tissue and the complexity of the bone repair process. In combination with biological materials, cells and biological factors can provide a highly effective and safe treatment strategy for bone repair and regeneration, especially based on these multifunctional hydrogel interface materials. However, itis still a challenge to formulate hydrogel materials with fascinating properties (e.g., biological activity, controllable biodegradability, mechanical strength, excellent cell/tissue adhesion, and controllable release properties) for their clinical applications in complex bone repair processes. In this review, we will highlight recent advances in developing functional interface hydrogels. We then discuss the barriers to producing of functional hydrogel materials without sacrificing their inherent properties, and potential applications in cartilage and bone repair are discussed. Multifunctional hydrogel interface materials can serve as a fundamental building block for bone tissue engineering.