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Here we report two novel synthetic riboswitches that respond to ASP2905 and theophylline and function in reconstituted cell-free protein synthesis (CFPS) system. We encapsulated the CFPS system as well as DNA-templated encoding reporter genes regulated by these orthogonal riboswitches inside liposomes, and achieved switchable and orthogonal control over gene expression by external stimulation with the cognate ligands. [ABSTRACT FROM AUTHOR]

Droplet Interface Bilayers (DIBs) constitute a commonly used model of artificial membranes for synthetic biology research applications. However, their practical use is often limited by their requirement to be surrounded by oil. Here we demonstrate in-situ bilayer manipulation of submillimeter, hydrogel-encapsulated droplet interface bilayers (eDIBs). Monolithic, Cyclic Olefin Copolymer/Nylon 3D-printed microfluidic devices facilitated the eDIB formation through high-order emulsification. By exposing the eDIB capsules to varying lysophosphatidylcholine (LPC) concentrations, we investigated the interaction of lysolipids with three-dimensional DIB networks. Micellar LPC concentrations triggered the bursting of encapsulated droplet networks, while at lower concentrations the droplet network endured structural changes, precisely affecting the membrane dimensions. This chemically-mediated manipulation of enclosed, 3D-orchestrated membrane mimics, facilitates the exploration of readily accessible compartmentalized artificial cellular machinery. Collectively, the droplet-based construct can pose as a chemically responsive soft material for studying membrane mechanics, and drug delivery, by controlling the cargo release from artificial cell chassis. Droplet interface bilayers can be used as a model of artificial membranes for synthetic biology and drug delivery applications, however, their accessibility using non-invasive techniques remains challenging. Here, the authors develop an in-situ bilayer manipulation of encapsulated droplet interface bilayers in hydrogel capsules, generated by high-order emulsification in monolithic 3D-printed microfluidic devices. [ABSTRACT FROM AUTHOR]

Embryonic stem-like cells (ES-like cells) are promising for medical research and clinical applications. Traditional methods involve "Yamanaka" transcription (OSKM) to derive these cells from somatic cells in vitro. Recently, a novel approach has emerged, obtaining ES-like cells from spermatogonia stem cells (SSCs) in a time-related process without adding artificial additives to cell cultures, like transcription factors or small molecules such as pten or p53 inhibitors. This study aims to investigate the role of the Nanog in the conversion of SSCs to pluripotent stem cells through both in silico analysis and in vitro experiments. We used bioinformatic methods and microarray data to find significant genes connected to this derivation path, to construct PPI networks, using enrichment analysis, and to construct miRNA-lncRNA networks, as well as in vitro experiments, immunostaining, and Fluidigm qPCR analysis to connect the dots of Nanog significance. We concluded that Nanog is one of the most crucial differentially expressed genes during SSC conversion, collaborating with critical regulators such as Sox2, Dazl, Pou5f1, Dnmt3, and Cdh1. This intricate protein network positions Nanog as a pivotal factor in pathway enrichment for generating ES-like cells, including Wnt signaling, focal adhesion, and PI3K-Akt-mTOR signaling. Nanog expression is presumed to play a vital role in deriving ES-like cells from SSCs in vitro. Finding its pivotal role in this path illuminates future research and clinical applications. [ABSTRACT FROM AUTHOR]

Mechanical stimulation is prevalent within organisms, and appropriate regulation of such stimulation can significantly enhance cellular functions. Consequently, the in vitro construction and simulation of mechanical stimulation have emerged as a research hotspot in biomechanics. In recent years, a class of artificial muscles named electroactive polymers (EAPs), especially ionic EAPs, have shown promising applications in biomechanics. While several techniques utilizing ionic EAPs for cell mechanical stimulation have been reported, further research is needed to advance and enhance their practical applications. Here, we prepared a microactuator array based on ionic EAP artificial muscles for cell mechanical stimulation. As a preliminary effort, we created a 5 × 5 microactuator array on a supporting membrane by employing laser cutting. We evaluated the electro-actuation performance of the microactuators through experimental testing and numerical simulations, affirming the potential use of the microactuator array for cell mechanical stimulation. The devised approach could inspire innovative design concepts in the development of miniaturized intelligent electronic devices, not only in biomechanics and biomimetics but also in other related fields. [ABSTRACT FROM AUTHOR]

Designing and assembling artificial cells (ACs) is a core direction in bottom‐up synthetic biology. Here, the advancements in the past 3 years in engineering ACs with focus on compartmentalization and surface modifications with the aim for their integration in semi‐synthetic tissue are outlined. Compartmentalization in vesicles, coacervates and hydrogels are discussed for encapsulated catalysis or cytoskeleton formation including the use of components of mammalian cells to increase the ACs’ complexity. Following on, the surface modification of the ACs is reviewed due to its relevance when integration of ACs with mammalian cells into semi‐synthetic tissue is the goal. Finally, the interaction of ACs and mammalian cells for cellular communication or the fabrication of semi‐synthetic tissue toward therapeutic opportunities is outlined, before a short perspective is provided. [ABSTRACT FROM AUTHOR]

Fossil fuel prices are increasing day by day due to growing demand and resource limitations. This situation shifts conventional electricity generation to renewable power generation. Among renewables, solar photovoltaic (PV) energy is very promising as the third fastest growing one. However, PV system modeling requires the estimation of unknown parameters of PV cells and modules. This problem remains a compelling task due to its multi-dimensional, multi-model and non-linear characteristics. In order to contribute to the solution of this optimization problem, this work makes a detailed comparison of artificial hummingbird algorithm, artificial rabbits optimization, enhanced Jaya algorithm, flow direction algorithm and artificial gorilla troops optimizer for determining the unknown parameters of PV models. Experimental results demonstrate that artificial hummingbird algorithm in single diode modeling of PV cell, flow direction algorithm in double diode modeling of PV cell and artificial rabbits optimization in single diode modeling of PV module are found to be capable of estimating accurate and efficient design coefficients for PV systems. In addition, the mentioned metaheuristic algorithms show reasonable convergence characteristics for the corresponding PV models. [ABSTRACT FROM AUTHOR]

Cell membrane composed of lipid bilayer is a selectively permeable membrane that only allows specific molecules to pass through. While such selectivity is essential for the survival and function of cells, there exist instances when it is necessary to overcome the cell membrane barrier. Study on the artificial cell membrane barrier breakthrough strategies is of great significance for the development of drug delivery systems and the understanding of cellular behaviors. Herein, the advancements in the development of strategies for opening cell membrane barriers over the past decade are summarized. The main transmembrane mechanisms are elucidated and then divided into three categories, i.e., cell perforation via microinjection/external physical fields, cell endocytosis‐assisted construction of artificial transmembrane channels, and untethered micro/nanomachines. Next, the potential applications after opening the cell membrane are discussed, which mainly focus on the transmembrane cargo delivery into the cell and endogenous substance extraction out from the cell. Finally, this review outlines the current challenges that impede the realization of practical applications and presents an outlook of future opportunities to promote further development. Through overcoming the challenges, it is anticipated that artificial cell membrane breakthrough strategies will provide a revolutionized tool in the near future to advance the field of biomedicine and biotechnology. [ABSTRACT FROM AUTHOR]

The progress of precision oncology medicine is always limited by the tumor off‐targeting, the drug side effects, and the treatment inefficiency due to the complex and ever‐changing tumor microenvironment. Living cells, such as blood cells and immune cells, exhibit natural tumor tropism, controllable physicochemical modification, and excellent biocompatibility, which provide an advantageous pathway for innovative and efficient tumor suppression. Armed with nanoengineering techniques, artificial living cells harness their inherent biological properties to precisely identify and eradicate tumors, demonstrating broad biological application prospects and great transformational potential in personalized cancer therapy. Here, the recent advances of living cell‐based bionanobots including platelets, red blood cells, neutrophil, macrophage, and CAR‐T cells for cancer precision therapy and immune regulation are summarized, and the efficient anti‐tumor strategies for engineering living cell nanorobots to overcome complex biological barriers and immune suppression are also outlined (e.g., immunotherapy, sonodynamic therapy, chemo/radiotherapy, and phototherapy). In addition, the study discusses the advantages, limitations, and current challenges of artificial living cell‐based drug delivery systems, and provide perspectives on the future development of living cell‐mediated precision tumor nanomedicine. [ABSTRACT FROM AUTHOR]

The exponential growth of research on artificial cells and organelles underscores their potential as tools to advance the understanding of fundamental biological processes. The bottom–up construction from a variety of building blocks at the micro‐ and nanoscale, in combination with biomolecules is key to developing artificial cells. In this review, artificial cells are focused upon based on compartments where polymers are the main constituent of the assembly. Polymers are of particular interest due to their incredible chemical variety and the advantage of tuning the properties and functionality of their assemblies. First, the architectures of micro‐ and nanoscale polymer assemblies are introduced and then their usage as building blocks is elaborated upon. Different membrane‐bound and membrane‐less compartments and supramolecular structures and how they combine into advanced synthetic cells are presented. Then, the functional aspects are explored, addressing how artificial organelles in giant compartments mimic cellular processes. Finally, how artificial cells communicate with their surrounding and each other such as to adapt to an ever‐changing environment and achieve collective behavior as a steppingstone toward artificial tissues, is taken a look at. Engineering artificial cells with highly controllable and programmable features open new avenues for the development of sophisticated multifunctional systems. [ABSTRACT FROM AUTHOR]

Cortex-like cytoskeleton, a thin layer of cross-linked cytoplasmic proteins underlying the cell membrane, plays an essential role in modulating membrane behavior and cell surface properties. However, bottom-up construction of functional cortex-like cytoskeleton in artificial cells remains a challenge. Here, we present metal-phenolic networks as artificial cortical cytoskeletons in liposome-based artificial cells. The metal-phenolic cytoskeleton-reinforced artificial cells exhibit long-term stability, enhanced resistance to a variety of harsh environments, tunable permeability, and well-controlled morphologies. We anticipate that our stable artificial cell models will stride forward to practical applications of liposome-based microsystem. [ABSTRACT FROM AUTHOR]

Cells are small, closed spaces filled with various types of macromolecules. Although it is shown that the characteristics of biochemical reactions in vitro are quite different from those in living cells, the role of the co‐existence of various macromolecules in cell‐size space remains still elusive. Here, using a constructive approach, it is demonstrated that the co‐existence of various macromolecules themselves has the ability to tune protein localization for spatiotemporal regulation and a biochemical reaction system in a cell‐size space. Both experimental and theoretical analyses reveal that enhancement of interfacial effects by a large surface‐area‐to‐volume ratio facilitates membrane localization of molecules in the cell‐size space, and the interfacial effects are alleviated by competitive binding to lipid membranes among multiple proteins even if their membrane affinities are weak. These results indicate that competition for membrane binding among various macromolecules in the cell‐size space plays a role in regulating the spatiotemporal molecular organization and biochemical reaction networks. These findings shed light on the importance of surrounding molecules for biochemical reactions using purified elements in small spaces. [ABSTRACT FROM AUTHOR]

Blood scarcity is one of the main causes of healthcare disruptions worldwide, with blood shortages occurring at an alarming rate. Over the last decades, blood substitutes have aimed at reinforcing the supply of blood, with several products (e.g., hemoglobin (Hb)‐based oxygen (O2) carriers, perfluorocarbons (PFC)) achieving a limited degree of success. Regardless, there is still no widespread solution to this problem due to persistent challenges in product safety and scalability. In this Review, different advances are described in the field of blood substitution, particularly in the development of artificial red blood cells, otherwise known as engineered erythrocytes (EE). The different strategies are categorized into natural, synthetic, or hybrid approaches, and discuss their potential in terms of safety and scalability. Synthetic EEs are identified as the most powerful approach, and describe erythrocytes from a materials engineering perspective. Their biological structure and function are reviewed, as well as explore different methods of assembling a material‐based cell. Specifically, it is discussed how to recreate size, shape, and deformability through particle fabrication, and how to recreate the functional machinery through synthetic biology and nanotechnology. It is concluded by describing the versatile nature of synthetic erythrocytes in medicine and pharmaceuticals and propose specific directions for the field of erythrocyte engineering. [ABSTRACT FROM AUTHOR]

Excess cortisol release is associated with numerous health concerns, including psychiatric issues (i.e., anxiety, insomnia, and depression) and nonpsychiatric issues (i.e., osteoporosis). The aim of this study was to assess the in vitro inhibition of cortisol release, bioaccessibility, and bioavailability exerted by a chemically characterized Scutellaria lateriflora L. extract (SLE). The treatment of H295R cells with SLE at increasing, noncytotoxic, concentrations (5–30 ng/mL) showed significant inhibition of cortisol release ranging from 58 to 91%. The in vitro simulated gastric, duodenal, and gastroduodenal digestions, induced statistically significant reductions (p < 0.0001) in the bioactive polyphenolic compounds that most represented SLE. Bioavailability studies on duodenal digested SLE, using Caco-2 cells grown on transwell inserts and a parallel artificial membrane permeability assay, indicated oroxylin A glucuronide and oroxylin A were the only bioactive compounds able to cross the Caco-2 cell membrane and the artificial lipid membrane, respectively. The results suggest possible applications of SLE as a food supplement ingredient against cortisol-mediated stress response and the use of gastroresistant oral dosage forms to partially prevent the degradation of SLE bioactive compounds. In vivo studies and clinical trials remain necessary to draw a conclusion on the efficacy and tolerability of this plant extract. [ABSTRACT FROM AUTHOR]

Tobacco product use is a risk factor in the development of oral cancer, although epidemiology studies show this risk is far less with smokeless tobacco product use than cigarette smoking. While smokeless tobacco contains harmful and potentially harmful constituents (HPHCs), the oral permeation of HPHCs in oral tobacco products is not completely understood. To improve the understanding, three different extract concentrations of the CORESTA reference products (CRP) for snus (CRP1.1) and moist snuff (CRP2.1) were applied to cellular tissue derived from two donors of EpiOral™ model, a 3D human buccal model, and permeation of nicotine and tobacco-specific nitrosamines (TSNAs) were measured over two hours. Permeation of 0.15% caffeine in complete artificial saliva and cell viability were also measured. Results showed that a consistent and concentration dependent cumulative permeation of nicotine and TSNAs was observed with high percent recovery in all conditions. A high degree of sensitivity was seen for all analytes, with minimal cytotoxicity for both CRPs. The data presented here show the EpiOral™ model is fit-for-purpose to evaluate the permeation of nicotine and TSNAs in nicotine-containing snus and moist snuff oral tobacco. • Fit-for-purpose 3D buccal in vitro model for smokeless tobacco product permeation. • Permeation of TSNAs and nicotine measured simultaneously over 2 h. • High degree of sensitivity for TSNAs and nicotine was observed in this model. [ABSTRACT FROM AUTHOR]

To develop artificial cell models that mimic living cells, cell-sized lipid vesicles encapsulating cell-free protein synthesis (CFPS) systems are useful for protein expressions or artificial gene circuits for vesicle–vesicle communications. Therefore, investigating the transcriptional and translational properties of CFPS systems in lipid vesicles is important for maximizing the synthesis and functions of proteins. Although transcription and translation using CFPS systems inside lipid vesicles are more important than that outside lipid vesicles, the former processes are not investigated by changing the lipid composition of lipid vesicles. Herein, we investigated changes in transcription and translation using CFPS systems inside giant lipid vesicles (approximately 5–20 μm in diameter) caused by changing the lipid composition of lipid vesicles containing neutral, positively, and negatively charged lipids. After incubating for 30 min, 1 h, 2 h, and 4 h, the transcriptional and translational activities in these lipid vesicles were determined by detecting the fluorescence intensities of the fluorogenic RNA aptamer on the 3′-untranslated region of mRNA (transcription) and the fluorescent protein sfCherry (translation), respectively. The results revealed that transcriptional and translational activities in a lipid vesicle containing positively charged lipids were high when the protein was synthesized using the CFPS system inside the lipid vesicle. Thus, the present study provides an experimental basis for constructing complex artificial cell models using bottom-up approaches. [ABSTRACT FROM AUTHOR]

Hydrogen production from renewable electricity offers an eco-friendly alternative to fossil fuels. Proton exchange membrane (PEM) electrolysis is a well-known method for this purpose. Studies have primarily focused on reducing costs of noble catalysts, improving efficiency, managing system degradation, and addressing membrane thinning caused by contaminated cations. However, techniques for PEM recovery post-degradation are still under development. This study investigated the effects of cations on PEM cells using artificial soft water, and analyzed two recovery methods to restore cell performance. Our findings indicate a significant rise in cell operating voltage and a decrease hydrogen production over 8 h of operation with soft water. After introducing both recovery methods, the initial operating value was reinstated in both cases. Only nitric acid treatment, however, achieved hydrogen production levels comparable to those of ultrapure water. • The cations contaminated by soft water diminished the MEA cell performance. • We investigate two recovery methods to regain cell voltage and hydrogen generation. • Nitric acid treatment could provide an effective way to recover the cell performance. [ABSTRACT FROM AUTHOR]

Nanoencapsulation of living cells within artificial shells is a powerful approach for augmenting the inherent capacity of cells and enabling the acquisition of extrinsic functions. However, the current state of the field requires the development of nanoshells that can dynamically sense and adapt to environmental changes by undergoing transformations in form and composition. This paper reports the compositional transformation of an enzyme‐embedded nanoshell of Fe3+‐trimesic acid complex to an iron phosphate shell in phosphate‐containing media. The cytocompatible transformation allows the nanoshells to release functional molecules without loss of activities and biorecognition, while preserving the initial shell properties, such as cytoprotection. Demonstrations include the lysis and killing of Escherichia coli by lysozyme, and the secretion of interleukin‐2 by Jurkat T cells in response to paracrine stimulation by antibodies. This work on micrometric Transformers will benefit the creation of cell‐in‐shell nanobiohybrids that can interact with their surroundings in active and adaptive ways. [ABSTRACT FROM AUTHOR]

There has been increasing interest in methods to generate synthetic lipid membranes as key constituents of artificial cells or to develop new tools for remodeling membranes in living cells. However, the biosynthesis of phospholipids involves elaborate enzymatic pathways that are challenging to reconstitute in vitro. An alternative approach is to use chemical reactions to non‐enzymatically generate natural or non‐canonical phospholipids de novo. Previous reports have shown that synthetic lipid membranes can be formed in situ using various ligation chemistries, but these methods lack biocompatibility and/or suffer from slow kinetics at physiological pH. Thus, it would be valuable to develop chemoselective strategies for synthesizing phospholipids from water‐soluble precursors that are compatible with synthetic or living cells Here, we demonstrate that amide‐forming ligations between lipid precursors bearing hydroxylamines and α‐ketoacids (KAs) or potassium acyltrifluoroborates (KATs) can be used to prepare non‐canonical phospholipids at physiological pH conditions. The generated amide‐linked phospholipids spontaneously self‐assemble into cell‐like micron‐sized vesicles similar to natural phospholipid membranes. We show that lipid synthesis using KAT ligation proceeds extremely rapidly, and the high selectivity and biocompatibility of the approach facilitates the in situ synthesis of phospholipids and associated membranes in living cells. [ABSTRACT FROM AUTHOR]

There has been increasing interest in methods to generate synthetic lipid membranes as key constituents of artificial cells or to develop new tools for remodeling membranes in living cells. However, the biosynthesis of phospholipids involves elaborate enzymatic pathways that are challenging to reconstitute in vitro. An alternative approach is to use chemical reactions to non‐enzymatically generate natural or non‐canonical phospholipids de novo. Previous reports have shown that synthetic lipid membranes can be formed in situ using various ligation chemistries, but these methods lack biocompatibility and/or suffer from slow kinetics at physiological pH. Thus, it would be valuable to develop chemoselective strategies for synthesizing phospholipids from water‐soluble precursors that are compatible with synthetic or living cells Here, we demonstrate that amide‐forming ligations between lipid precursors bearing hydroxylamines and α‐ketoacids (KAs) or potassium acyltrifluoroborates (KATs) can be used to prepare non‐canonical phospholipids at physiological pH conditions. The generated amide‐linked phospholipids spontaneously self‐assemble into cell‐like micron‐sized vesicles similar to natural phospholipid membranes. We show that lipid synthesis using KAT ligation proceeds extremely rapidly, and the high selectivity and biocompatibility of the approach facilitates the in situ synthesis of phospholipids and associated membranes in living cells. [ABSTRACT FROM AUTHOR]

Biohybrid actuators aim to leverage the various advantages of biological cells over artificial components to build novel compliant machines with high performance and autonomy. Significant advances have been made in bio-fabrication technologies, enabling the realization of muscle-powered bio-actuators. However, the mechanics of muscle-scaffold coupling has been relatively understudied, limiting the development of bio-actuators to intuitive or biomimetic designs. Here, we consider the case of implementing muscle-based actuation for soft robotic swimmers operating at low Reynolds numbers. We develop an analytical model to describe the elasto-hydrodynamic problem and identify key design parameters. Muscle contraction dynamics is characterized experimentally and the implications of nonlinear amplitude-frequency relationship of muscle-based actuation are discussed. We show that a novel bio-actuator with high performance can be developed by introducing compliant flexural mechanisms undergoing large deflection. Geometric nonlinearities are accounted for in the analysis of the force-deflection relationship for the flexural mechanism. Our results show that for expected muscle contraction forces, this novel bio-actuator can outperform previous muscle-powered swimmers by up to two orders of magnitude in swimming speed. [ABSTRACT FROM AUTHOR]

Engineering artificial mechanosensory hair cells offers a promising avenue for developing diverse biosensors spanning applications from biomedicine to underwater sensing. Unfortunately, current artificial sensory hair cells do not have the ability to simultaneously achieve ultrahigh sensitivity with low-frequency threshold detection (e.g., 0.1 Hz). This work aimed to solve this gap by developing an artificial sensory hair cell inspired by the vestibular sensory apparatus, which has such functional capabilities. For device characterization and response testing, the sensory unit was inserted in a 3D printed lateral semicircular canal (LSCC) mimicking the environment of the labyrinth. The sensor was fabricated based on platinum (Pt) thin film which was reinforced by carbon nanofibers (CNFs). A Pi-shaped hair cell sensor was created as the sensing element which was tested under various conditions of simulated head motion. Results reveal the hair cell sensor displayed markedly higher sensitivity compared to other reported artificial hair cell sensors (e.g., 21.47 mV Hz−1 at 60°) and low frequency detection capability, 0.1 Hz < f < 1.5 Hz. Moreover, like the LSCC hair cells in biology, the fabricated sensor was most sensitive in a given plane of rotational motion, demonstrating features of directional sensitivity. [ABSTRACT FROM AUTHOR]

Artificial cell and organelle construction has recently gained substantial attention to generate simplified models for understanding of biological phenomena, or micro‐ and nanomachines for biomedical and biotechnological applications. A wide array of building blocks has been employed to build these systems as membraneless structures with the ability to compartmentalize chemical reactions by enhanced partitioning, or as membrane‐defined entities that provide a physical barrier that inhibits the interference of external factors. While these systems present unique properties that enable high fidelity to biological processes, they present limited ability to recreate the high selectivity and specificity of small molecule trafficking observed in biological membranes. Owing to their high chemical versatility, polymers can be leveraged to generate 3D structures that resemble biological membranes while providing transmembrane chemical motifs that enable responsiveness to a wide array of stimuli. This Concept Article discusses the ability to control membrane transport facilitating the emergence of out‐of‐equilibrium feedback mechanisms that ultimately modulate enzymatic rates. This can be employed to engineer future artificial cells and organelles that display homeostasis as a mechanism of self‐adaptation to continuously evolving environments. [ABSTRACT FROM AUTHOR]

How do the living systems emerge from non-living molecular assemblies? What physical and chemical principles supported the process? To address these questions, a promising strategy is to artificially reconstruct living cells in a bottom-up way. Recently, the authors developed the "synthetic minimal cell" system showing recursive growth and division cycles, where the concepts of information molecules, metabolic pathways, and cell reproduction were artificially and concisely redesigned with the vesicle-based system. We intentionally avoided using the sophisticated molecular machinery of the biological cells and tried to redesign the cells in the simplest forms. This review focuses on the similarities and differences between the biological cells and our synthetic minimal cell concerning each concept of cells. Such comparisons between natural and artificial cells will provide insights on how the molecules should be assembled to create living systems to the wide readers in the field of synthetic biology, artificial cells, and protocells research. This review article is an extended version of the Japanese article "Growth and division of vesicles coupled with information molecules," published in SEIBUTSU-BUTSURI vol. 61, p. [ABSTRACT FROM AUTHOR]

Over the past few decades, there have been increasing global efforts to limit or ban the use of animals for testing cosmetic products. This ambition has been at the heart of international endeavours to develop new in vitro and animal-free approaches for assessing the safety of cosmetics. While several of these new approach methodologies (NAMs) have been approved for assessing different toxicological endpoints in the UK and across the EU, there remains an absence of animal-free methods for screening for dermal absorption; a measure that assesses the degree to which chemical substances can become systemically available through contact with human skin. Here, we identify some of the major technical barriers that have impacted regulatory recognition of an in vitro skin model for this purpose and propose how these could be overcome on-chip using artificial cells engineered from the bottom-up. As part of our future perspective, we suggest how this could be realised using a digital biomanufacturing pipeline that connects the design, microfluidic generation and 3D printing of artificial cells into user-crafted synthetic tissues. We highlight milestone achievements towards this goal, identify future challenges, and suggest how the ability to engineer animal-free skin models could have significant long-term consequences for dermal absorption screening, as well as for other applications. [ABSTRACT FROM AUTHOR]

Skeletal muscle comprises a large, heterogeneous assortment of cell populations that interact to maintain muscle homeostasis, but little is known about the mechanism that controls myogenic development in response to artificial selection. Different pig (Sus scrofa) breeds exhibit distinct muscle phenotypes resulting from domestication and selective breeding. Using unbiased single‐cell transcriptomic sequencing analysis (scRNA‐seq), the impact of artificial selection on cell profiles is investigated in neonatal skeletal muscle of pigs. This work provides panoramic muscle‐resident cell profiles and identifies novel and breed‐specific cells, mapping them on pseudotime trajectories. Artificial selection has elicited significant changes in muscle‐resident cell profiles, while conserving signs of generational environmental challenges. These results suggest that fibro‐adipogenic progenitors serve as a cellular interaction hub and that specific transcription factors identified here may serve as candidate target regulons for the pursuit of a specific muscle phenotype. Furthermore, a cross‐species comparison of humans, mice, and pigs illustrates the conservation and divergence of mammalian muscle ontology. The findings of this study reveal shifts in cellular heterogeneity, novel cell subpopulations, and their interactions that may greatly facilitate the understanding of the mechanism underlying divergent muscle phenotypes arising from artificial selection. [ABSTRACT FROM AUTHOR]

On 25 July 2023, a workshop entitled "Molecular Communication Approaches for Wetware Artificial Life" took place as a satellite event at the international conference ALIFE 2023 (The 2023 Conference on Artificial Life). In this report, we comment on the workshop by focusing on the main theme and the motivations that led us to develop this initiative. In particular, we highlight how recent progress in synthetic biology and in the study of molecular communication from an engineering perspective can be fruitfully joined to provide a powerful platform to develop frontier research lines in "wetware" Artificial Life. The talks presented at the workshop are briefly summarized. This report is, ultimately, an opportunity to promote an emerging field that calls for collaborative efforts of scholars from multiple disciplines, from chemistry to molecular biology, from communication engineering to nanotechnology, and up to those interested in more theoretical aspects about complex artificial systems that mimic natural ones. [ABSTRACT FROM AUTHOR]

Characteristics of artificial waveguide lines composed of finite size artificial cells are analyzed and discussed with relation to designing the travelling wave parametric amplifiers. From this point of view, flux driven amplifier suggested recently can be considered as the most successful amplifier design. To increase dynamic range of the amplifier, dc SQUID cells of the artificial line in use can be substituted for bi-SQUID cells. The 1 dB compression points of the amplifier gain are calculated and compared for both types of the cells. [ABSTRACT FROM AUTHOR]

In the quest to produce artificial cells, one key challenge that remains to be solved is the recreation of a complex cellular membrane. Among the existing models, giant unilamellar vesicles (GUVs) are particularly interesting due to their intrinsic compartmentalisation ability and their resemblance in size and shape to eukaryotic cells. Many techniques have been developed to produce GUVs all having inherent advantages and disadvantages. Here, the authors show that fluorinated silica nanoparticles (FNPs) used to form Pickering emulsions in a fluorinated oil can destabilise lipid nanosystems to template the formation of GUVs. This technique enables GUV production across a broad spectrum of buffer conditions, while preventing the leakage of the encapsulated components into the oil phase. Furthermore, a simple centrifugation process is sufficient for the release of the emulsion‐trapped GUVs, bypassing the need to use emulsion‐destabilising chemicals. With fluorescent FNPs and transmission electron microscopy, the authors confirm that FNPs are efficiently removed, producing contaminant‐free GUVs. Further experiments assessing the lateral diffusion of lipids and unilamellarity of the GUVs demonstrate that they are comparable to GUVs produced via electroformation. Finally, the ability of incorporating transmembrane proteins is demonstrated, highlighting the potential of this method for the production of GUVs for artificial cell applications. [ABSTRACT FROM AUTHOR]

Surfactin is an excellent biosurfactant with a wide range of application prospects in many industrial fields. However, its low productivity and high cost have largely limited its commercial applications. In this review, the pathways for surfactin synthesis in Bacillus strains are summarized and discussed. Further, the latest strategies for improving surfactin production, including: medium optimization, genome engineering methods (rational genetic engineering, genome reduction, and genome shuffling), heterologous synthesis, and the use of synthetic biology combined with metabolic engineering approaches to construct high-quality artificial cells for surfactin production using xylose, are described. Finally, the prospects for improving surfactin synthesis are discussed in detail. [ABSTRACT FROM AUTHOR]

Simple Summary: Cancer is the main cause of human death. Nanomedicine provides a new strategy for the treatment of diverse cancers. Among them, superparamagnetic artificial cell PLGA-Fe3O4 micro/nanocapsules demand great attention due to their excellent properties, such as targeted delivery, magnetic response, and biocompatibility. The aim of this review is to summarize the application of superparamagnetic artificial cells (PLGA-Fe3O4) micro/nanocapsules in cancer drug targeted delivery and their preparation methods, providing insights into the future development of superparamagnetic artificial cells (PLGA nano/microcapsules) for magnetic targeting in cancer treatment. Artificial cells have been extensively used in many fields, such as nanomedicine, biotherapy, blood substitutes, drug delivery, enzyme/gene therapy, cancer therapy, and the COVID-19 vaccine. The unique properties of superparamagnetic Fe3O4 nanoparticles have contributed to increased interest in using superparamagnetic artificial cells (PLGA-Fe3O4 micro/nanocapsules) for targeted therapy. In this review, the preparation methods of Fe3O4 NPs and superparamagnetic artificial cell PLGA-drug-Fe3O4 micro/nanocapsules are discussed. This review also focuses on the recent progress of superparamagnetic PLGA-drug-Fe3O4 micro/nanocapsules as targeted therapeutics. We shall concentrate on the use of superparamagnetic artificial cells in the form of PLGA-drug-Fe3O4 nanocapsules for magnetic hyperthermia/photothermal therapy and cancer therapies, including lung breast cancer and glioblastoma. [ABSTRACT FROM AUTHOR]

Engineered T cells hold great promise to become part of an effective HIV cure strategy, but it is currently unclear how best to redirect T cells to target HIV. To gain insight, we generated engineered T cells using lentiviral vectors encoding one of three distinct HIV-specific T cell receptors (TCRs) or a previously optimized HIV-targeting chimeric antigen receptor (CAR) and compared their functional capabilities. All engineered T cells had robust, antigen-specific polyfunctional cytokine profiles when mixed with artificial antigen-presenting cells. However, only the CAR T cells could potently control HIV replication. TCR affinity enhancement did not augment HIV control but did allow TCR T cells to recognize common HIV escape variants. Interestingly, either altering Nef activity or adding additional target epitopes into the HIV genome bolstered TCR T cell anti-HIV activity, but CAR T cells remained superior in their ability to control HIV replication. To better understand why CAR T cells control HIV replication better than TCR T cells, we performed a time course to determine when HIV-specific T cells were first able to activate Caspase 3 in HIV-infected targets. We demonstrated that CAR T cells recognized and killed HIV-infected targets more rapidly than TCR T cells, which correlates with their ability to control HIV replication. These studies suggest that the speed of target recognition and killing is a key determinant of whether engineered T cell therapies will be effective against infectious diseases. Author summary: Infusion of HIV-specific engineered T cells is a promising approach to eliminate HIV infected cells that reverse latency and begin to replicate HIV after ART withdrawal. However, it is unclear whether chimeric antigen receptors (CAR) or TCRs are the best approach to generate HIV-specific T cells for adoptive T cell therapy. We generated CD8 T cells expressing one of three HIV-specific TCRs (TCR-T) or a previously optimized HIV-specific CAR and interrogated which population controlled HIV replication more effectively. HIV-specific CAR T cells were far superior to any of the TCR-T cells. Increasing TCR affinity or interfering with the ability of Nef to downregulate MHC class I had modest effects on the ability TCR-T cells to control HIV. Inserting additional cognate epitopes within the HIV genome did improve the ability of TCR-T cells to control HIV but HIV CAR T cells were still superior. The ability to control HIV replication best correlated with the ability of engineered T cell to rapidly induce cell death in HIV-infected T cells, suggesting that the speed of recognition and initiation of T cell mediated killing is a key determinant on whether engineered T cells can control viral infections. [ABSTRACT FROM AUTHOR]

In recent years, research has explored the use of microRNA (miRNA) analysis in extracellular vesicles (EVs) as a minimally invasive strategy for the diagnosis and prediction of diseases. This is because miRNAs in EVs partly reflect the miRNA information and cellular status of the origin cells. However, not all intracellular miRNAs are internalized into EVs. Therefore, the miRNA information obtained from EVs is limited. To get more miRNA information, we aimed to produce artificial EVs (aEVs) encapsulating Argonaute 2 (Ago2) miRNA-binding protein, which actively incorporate miRNAs within themselves. In this study, we utilized the protein EPN-01, which is capable of releasing aEVs encapsulating it and associated proteins. This system enables us to obtain more miRNA species and increase each miRNA's yield in the EV fraction. Furthermore, we examined whether miRNAs in the EV fraction using our system reflect the cellular condition. In cells treated with CoCl2, a reagent for inducing a hypoxia-mimic state, we detected a change in the level of hypoxia marker miR-210 with aEVs. To the best of our knowledge, this is the first report on a method to increase the yield and variety of endogenous miRNAs in the EV fraction. This approach leads to improved accuracy of cell status assessment using miRNAs in EVs. [ABSTRACT FROM AUTHOR]

Current strategies to identify ligands for brain delivery select candidates based on preferential binding to cell-membrane components (CMC) on brain endothelial cells (EC). However, such strategies generate ligands with inherent brain specificity limitations, as the CMC (e.g., the transferrin receptor TfR1) are also significantly expressed on peripheral EC. Therefore, novel strategies are required to identify molecules allowing increased specificity of therapy brain delivery. Here, we demonstrate that, while individual CMC are shared between brain EC and peripheral EC, their endocytic internalization rate is markedly different. Such differential endocytic rate may be harnessed to identify molecular tags for brain targeting based on their selective retention on the surface of brain EC, thereby generating 'artificial' targets specifically on the brain vasculature. By quantifying the retention of labelled proteins on the cell membrane, we measured the general endocytic rate of primary brain EC to be less than half that of primary peripheral (liver and lung) EC. In addition, through bio-panning of phage-displayed peptide libraries, we unbiasedly probed the endocytic rate of individual CMC of liver, lung and brain endothelial cells. We identified phage-displayed peptides which bind to CMC common to all three endothelia phenotypes, but which are preferentially endocytosed into peripheral EC, resulting in selective retention on the surface of brain EC. Furthermore, we demonstrate that the synthesized free-form peptides are capable of generating artificial cell-surface targets for the intracellular delivery of model proteins into brain EC with increasing specificity over time. The developed identification paradigm, therefore, demonstrates that the lower endocytic rate of individual CMC on brain EC can be harnessed to identify peptides capable of generating 'artificial' targets for the selective delivery of proteins into the brain vasculature. In addition, our approach identifies brain-targeting peptides which would have been overlooked by conventional identification strategies, thereby increasing the repertoire of candidates to achieve specific therapy brain delivery. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is a systemic autoimmune disease (AD) caused by the aberrant attack of the immune system on its own joint tissues. Genetic and environmental factors are the main reasons of immune system impairment and high incidence of RA. Although there are medications on the market that lessen disease activity, there is no known cure for RA, and patients are at risk in varying degrees of systemic immunosuppression. By transporting (encapsulating or surface binding) RA-related self-antigens, nucleic acids, immunomodulators, or cytokines, tolerogenic nanoparticles—also known as immunomodulatory nano-preparations—have the potential to gently regulate local immune responses and ultimately induce antigen-specific immune tolerance. We review the recent advances in immunomodulatory nano-preparations for delivering self-antigen or self-antigen plus immunomodulator, simulating apoptotic cell avatars in vivo, acting as artificial antigen-presenting cells, and based on scaffolds and gels, to provide a reference for developing new immunotherapies for RA. [ABSTRACT FROM AUTHOR]

Cell-free protein synthesis is emerging as a powerful tool to accelerate the progress of synthetic biology. Notably, cell-free systems that harness extracted synthetic machinery of cells can address many of the issues associated with the complexity and variability of living systems. In particular, cell-free systems can be programmed with various configurations of genetic information, providing great flexibility and accessibility to the field of synthetic biology. Empowered by recent progress, cell-free systems are now evolving into artificial biological systems that can be tailored for various applications, including on-demand biomanufacturing, diagnostics, and new materials design. Here, we review the key developments related to cell-free protein synthesis systems, and discuss the future directions of these promising technologies. [ABSTRACT FROM AUTHOR]

Modern medical research develops interest in sophisticated artificial nano‐ and microdevices for future treatment of human diseases related to biological dysfunctions. This covers the design of protocells capable of mimicking the structure and functionality of eukaryotic cells. The authors use artificial organelles based on trypsin‐loaded pH‐sensitive polymeric vesicles to provide macrophage‐like digestive functions under physiological conditions. Herein, an artificial cell is established where digestive artificial organelles (nanosize) are integrated into a protocell (microsize). With this method, mimicking crossing of different biological barriers, capture of model protein pathogens, and compartmentalized digestive function are possible. This allows the integration of different components (e.g., dextran as stabilizing block) and the diffusion of pathogens in simulated cytosolic environment under physiological conditions. An integrated characterization approach is carried out, with identifying electrospray ionization mass spectrometry as an excellent detection method for the degradation of a small peptide such as β‐amyloid. The degradation of model enzymes is measured by enzyme activity assays. This work is an important contribution to effective biomimicry with the design of cell‐like functions having potential for therapeutic action. [ABSTRACT FROM AUTHOR]

Controllable, self‐regenerating artificial cells (SRACs) can be a vital advancement in the field of synthetic biology, which seeks to create living cells by recombining various biological molecules in the lab. This represents, more importantly, the first step on a long journey toward creating reproductive cells from rather fragmentary biochemical mimics. However, it is still a difficult task to replicate the complex processes involved in cell regeneration, such as genetic material replication and cell membrane division, in artificially created spaces. This review highlights recent advances in the field of controllable, SRACs and the strategies to achieve the goal of creating such cells. Self‐regenerating cells start by replicating DNA and transferring it to a location where proteins can be synthesized. Functional but essential proteins must be synthesized for sustained energy generation and survival needs and function in the same liposomal space. Finally, self‐division and repeated cycling lead to autonomous, self‐regenerating cells. The pursuit of controllable, SRACs will enable authors to make bold advances in understanding life at the cellular level, ultimately providing an opportunity to use this knowledge to understand the nature of life. [ABSTRACT FROM AUTHOR]

In recent years, significant progress has been made in the emerging field of constructing biomimetic soft compartments with life‐like behaviors. Given that biological activities occur under a flux of energy and matter exchange, the implementation of rudimentary signaling pathways in artificial cells (protocells) is a prerequisite for the development of adaptive sense‐response phenotypes in cytomimetic models. Herein, recent approaches to the integration of signal transduction modules in model protocells prepared by bottom‐up construction are discussed. The approaches are classified into two categories involving invasive biochemical signals or non‐invasive physical stimuli. In the former mechanism, transducers with intrinsic recognition capability respond with high specificity, while in the latter, artificial cells respond through intra‐protocellular energy transduction. Although major challenges remain in the pursuit of a sophisticated artificial signaling network for the orchestration of higher‐order cytomimetic models, significant advances have been made in establishing rudimentary protocell communication networks, providing novel organizational models for the development of life‐like microsystems and new avenues in protoliving technologies. [ABSTRACT FROM AUTHOR]

Creating an artificial cell from the bottom up is a long‐standing challenge and, while significant progress has been made, the full realization of this goal remains elusive. Arguably, one of the biggest hurdles that researchers are facing now is the assembly of different modules of cell function inside a single container. Giant unilamellar vesicles (GUVs) have emerged as a suitable container with many methods available for their production. Well‐studied swelling‐based methods offer a wide range of lipid compositions but at the expense of limited encapsulation efficiency. Emulsion‐based methods, on the other hand, excel at encapsulation but are only effective with a limited set of membrane compositions and may entrap residual additives in the lipid bilayer. Since the ultimate artificial cell will need to comply with both specific membrane and encapsulation requirements, there is still no one‐method‐fits‐all solution for GUV formation available today. This review discusses the state of the art in different GUV production methods and their compatibility with GUV requirements and operational requirements such as reproducibility and ease of use. It concludes by identifying the most pressing issues and proposes potential avenues for future research to bring us one step closer to turning artificial cells into a reality. [ABSTRACT FROM AUTHOR]

Compartmentalization is crucial for the functioning of cells. Membranes enclose and protect the cell, regulate the transport of molecules entering and exiting the cell, and organize cellular machinery in subcompartments. In addition, membraneless condensates, or coacervates, offer dynamic compartments that act as biomolecular storage centers, organizational hubs, or reaction crucibles. Emerging evidence shows that phase‐separated membraneless bodies in the cell are involved in a wide range of functional interactions with cellular membranes, leading to transmembrane signaling, membrane remodeling, intracellular transport, and vesicle formation. Such functional and dynamic interplay between phase‐separated droplets and membranes also offers many potential benefits to artificial cells, as shown by recent studies involving coacervates and liposomes. Depending on the relative sizes and interaction strength between coacervates and membranes, coacervates can serve as artificial membraneless organelles inside liposomes, as templates for membrane assembly and hybrid artificial cell formation, as membrane remodelers for tubulation and possibly division, and finally, as cargo containers for transport and delivery of biomolecules across membranes by endocytosis or direct membrane crossing. Here, recent experimental examples of each of these functions are reviewed and the underlying physicochemical principles and possible future applications are discussed. [ABSTRACT FROM AUTHOR]

Creating a man‐made life in the laboratory is one of life science's most intriguing yet challenging problems. Advances in synthetic biology and related theories, particularly those related to the origin of life, have laid the groundwork for further exploration and understanding in this field of artificial life or man‐made life. But there remains a wealth of quantitative mathematical models and tools that have yet to be applied to this area. In this paper, we review the two main approaches often employed in the field of man‐made life: the top‐down approach that reduces the complexity of extant and existing living systems and the bottom‐up approach that integrates well‐defined components, by introducing the theoretical basis, recent advances, and their limitations. We then argue for another possible approach, namely "bottom‐up from the origin of life": Starting with the establishment of autocatalytic chemical reaction networks that employ physical boundaries as the initial compartments, then designing directed evolutionary systems, with the expectation that independent compartments will eventually emerge so that the system becomes free‐living. This approach is actually analogous to the process of how life originated. With this paper, we aim to stimulate the interest of synthetic biologists and experimentalists to consider a more theoretical perspective, and to promote the communication between the origin of life community and the synthetic man‐made life community. [ABSTRACT FROM AUTHOR]

We investigated the possibility of using Raman spectroscopy assisted by artificial intelligence methods to identify liver cancer cells and distinguish them from their Non-Tumor counterpart. To this aim, primary liver cells (40 Tumor and 40 Non-Tumor cells) obtained from resected hepatocellular carcinoma (HCC) tumor tissue and the adjacent non-tumor area (negative control) were analyzed by Raman micro-spectroscopy. Preliminarily, the cells were analyzed morphologically and spectrally. Then, three machine learning approaches, including multivariate models and neural networks, were simultaneously investigated and successfully used to analyze the cells' Raman data. The results clearly demonstrate the effectiveness of artificial intelligence (AI)-assisted Raman spectroscopy for Tumor cell classification and prediction with an accuracy of nearly 90% of correct predictions on a single spectrum. [ABSTRACT FROM AUTHOR]

Artificial cells are synthetic constructs that emulate natural cells, with potential applications in areas of energy science, environmental treatment, and the study of life's origins. Nevertheless, the construction of artificial cells is a formidable undertaking, given the intricate nature of natural cells in structures, functions, and working mechanisms. With precise control, high automation, and excellent uniformity, microfluidics has emerged as a promising approach for the construction of artificial cells. This review summarizes the latest microfluidic techniques utilized to construct artificial cells, ranging from simple droplets to sophisticated cell‐inspired systems. These include the generation of droplets, the production of vesicles (lipid‐based and polymer‐based vesicles), the fabrication of polymeric microparticles with various compartments, shapes, and microstructures, as well as the manufacture of sophisticated cell‐inspired systems. The characteristics of different methods for the construction of artificial cells are discussed in detail. Furthermore, the wide‐ranging applications of artificial cells are also showcased. Finally, contemporary obstacles and forthcoming advancements are discussed in the field of microfluidic‐based artificial cells. This review is supposed to stimulate research in the construction of more functional and natural‐like artificial cells, as well as works in the fields of material, biology, environment, medicine, and energy. [ABSTRACT FROM AUTHOR]

Object recognition by natural and artificial visual systems benefits from the identification of object boundaries. A useful cue for the detection of object boundaries is the superposition of luminance and color edges. To gain insight into the suitability of this cue for object recognition, we examined convolutional neural network models that had been trained to recognize objects in natural images. We focused specifically on units in the second convolutional layer whose activations are invariant to the spatial phase of a sinusoidal grating. Some of these units were tuned for a nonlinear combination of color and luminance, which is broadly consistent with a role in object boundary detection. Others were tuned for luminance alone, but very few were tuned for color alone. A literature review reveals that V1 complex cells have a similar distribution of tuning. We speculate that this pattern of sensitivity provides an efficient basis for object recognition, perhaps by mitigating the effects of lighting on luminance contrast polarity. The absence of a contrast polarity‐invariant representation of color alone suggests that it is redundant with other representations. [ABSTRACT FROM AUTHOR]

Background: The study and synthesis of membrane organelles are becoming increasingly important, not only as simplified cellular models for corresponding molecular and metabolic studies but also for applications in synthetic biology of artificial cells and drug delivery vehicles. Lipid droplets (LDs) are central organelles in cellular lipid metabolism and are involved in almost all metabolic processes. Multiple studies have also demonstrated a high correlation between LDs and metabolic diseases. During these processes, LDs reveal a highly dynamic character, with their lipid fraction, protein composition and subcellular localisation constantly changing in response to metabolic demands. However, the molecular mechanisms underlying these functions have not been fully understood due to the limitations of cell biology approaches. Fortunately, developments in synthetic biology have provided a huge breakthrough for metabolism research, and methods for in vitro synthesis of LDs have been successfully established, with great advances in protein binding, lipid function, membrane dynamics and enzymatic reactions. Aims and methods: In this review, we provide a comprehensive overview of the assembly and function of endogenous LDs, from the generation of lipid molecules to how they are assembled into LDs in the endoplasmic reticulum. In particular, we highlight two major classes of synthetic LD models for fabrication techniques and their recent advances in biology and explore their roles and challenges in achieving real applications of artificial LDs in the future. [ABSTRACT FROM AUTHOR]

Membrane trafficking is a fundamental mechanism for protein and lipid transport in eukaryotic cells and exhibits marked diversity among eukaryotic lineages with distinctive body plans and lifestyles. Diversification of the membrane trafficking system is associated with the expansion and secondary loss of key machinery components, including RAB GTPases, soluble N -ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) and adaptor proteins, during plant evolution. The number of AP180 N-terminal homology (ANTH) proteins, an adaptor family that regulates vesicle formation and cargo sorting during clathrin-mediated endocytosis, increases during plant evolution. In the genome of Arabidopsis thaliana , 18 genes for ANTH proteins have been identified, a higher number than that in yeast and animals, suggesting a distinctive diversification of ANTH proteins. Conversely, the liverwort Marchantia polymorpha possesses a simpler repertoire; only two genes encoding canonical ANTH proteins have been identified in its genome. Intriguingly, a non-canonical ANTH protein is encoded in the genome of M. polymorpha , which also harbors a putative kinase domain. Similar proteins have been detected in sporadic lineages of plants, suggesting their ancient origin and multiple secondary losses during evolution. We named this unique ANTH group phosphatidylinositol-binding clathrin assembly protein-K (PICALM-K) and characterized it in M. polymorpha using genetic, cell biology–based and artificial intelligence (AI)–based approaches. Our results indicate a flagella-related function of MpPICALM-K in spermatozoids, which is distinct from that of canonical ANTH proteins. Therefore, ANTH proteins have undergone significant functional diversification during evolution, and PICALM-K represents a plant-unique ANTH protein that is delivered by neofunctionalization through exon shuffling. [ABSTRACT FROM AUTHOR]

In recent years, there has been a growing interest in multi‐compartment systems as a means of developing materials that mimic the structure and function of biological cells. These hierarchical systems, including artificial cells and cell‐like reactors, can efficiently perform biochemical tasks by exploiting compartmentalization inspired by biological systems. However, the bottom‐up design of cell mimics presents significant challenges due to the need for precise and efficient assembly of components. This short review examines recent advances in droplet‐based microfluidics (DBM), which has emerged as a powerful technique for creating cell‐like systems with multi‐compartment architectures, precise composition, and biomimetic functionality. DBM has proven to be a reliable method for generating populations of cell‐mimics with a compartment‐in‐compartment structure, some of which have adaptable properties that resemble the dynamic properties of natural cells. Notable examples will be discussed to illustrate how droplet‐based microfluidics provides a versatile approach to create, manipulate, and study cell‐mimics. [ABSTRACT FROM AUTHOR]

Mimicking the structures and functions of cells to create artificial organelles has spurred the development of efficient strategies for production of hollow nanoreactors with biomimetic catalytic functions. However, such structure are challenging to fabricate and are thus rarely reported. We report the design of hollow nanoreactors with hollow multishelled structure (HoMS) and spatially loaded metal nanoparticles. Starting from a molecular‐level design strategy, well‐defined hollow multishelled structure phenolic resins (HoMS‐PR) and carbon (HoMS‐C) submicron particles were accurately constructed. HoMS‐C serves as an excellent, versatile platform, owing to its tunable properties with tailored functional sites for achieving precise spatial location of metal nanoparticles, internally encapsulated (Pd@HoMS‐C) or externally supported (Pd/HoMS‐C). Impressively, the combination of the delicate nanoarchitecture and spatially loaded metal nanoparticles endow the pair of nanoreactors with size–shape‐selective molecular recognition properties in catalytic semihydrogenation, including high activity and selectivity of Pd@HoMS‐C for small aliphatic substrates and Pd/HoMS‐C for large aromatic substrates. Theoretical calculations provide insight into the pair of nanoreactors with distinct behaviors due to the differences in energy barrier of substrate adsorption. This work provides guidance on the rational design and accurate construction of hollow nanoreactors with precisely located active sites and a finely modulated microenvironment by mimicking the functions of cells. [ABSTRACT FROM AUTHOR]

Mimicking the structures and functions of cells to create artificial organelles has spurred the development of efficient strategies for production of hollow nanoreactors with biomimetic catalytic functions. However, such structure are challenging to fabricate and are thus rarely reported. We report the design of hollow nanoreactors with hollow multishelled structure (HoMS) and spatially loaded metal nanoparticles. Starting from a molecular‐level design strategy, well‐defined hollow multishelled structure phenolic resins (HoMS‐PR) and carbon (HoMS‐C) submicron particles were accurately constructed. HoMS‐C serves as an excellent, versatile platform, owing to its tunable properties with tailored functional sites for achieving precise spatial location of metal nanoparticles, internally encapsulated (Pd@HoMS‐C) or externally supported (Pd/HoMS‐C). Impressively, the combination of the delicate nanoarchitecture and spatially loaded metal nanoparticles endow the pair of nanoreactors with size–shape‐selective molecular recognition properties in catalytic semihydrogenation, including high activity and selectivity of Pd@HoMS‐C for small aliphatic substrates and Pd/HoMS‐C for large aromatic substrates. Theoretical calculations provide insight into the pair of nanoreactors with distinct behaviors due to the differences in energy barrier of substrate adsorption. This work provides guidance on the rational design and accurate construction of hollow nanoreactors with precisely located active sites and a finely modulated microenvironment by mimicking the functions of cells. [ABSTRACT FROM AUTHOR]

Tumor necrosis is a recurrent characteristic of head and neck squamous cell carcinomas (HNSCCs). There is a need for more investigations on the influence of biomolecules released by these necrotic foci in the HNSCC tumor microenvironment. It is suspected that a fraction of the biomolecules released by necrotic cells are damage-associated molecular patterns (DAMPs), which are known to be natural endogenous ligands of Toll-like receptors (TLRs), including, among others, proteins and nucleic acids. However, there has been no direct demonstration that biomolecules released by HNSCC necrotic cells can activate TLRs. Our aim was to investigate whether some of these molecules could behave as agonists of the TLR3, either in vitro or in vivo. We chose a functional approach based on reporter cell exhibiting artificial TLR3 expression and downstream release of secreted alkaline phosphatase. The production of biomolecules activating TLR3 was first investigated in vitro using three HNSCC cell lines subjected to various pronecrotic stimuli (external irradiation, serum starvation, hypoxia and oxidative stress). TLR3 agonists were also investigated in necrotic tumor fluids from five oral cancer patients and three mouse tumor grafts. The release of biomolecules activating TLR3 was demonstrated for all three HNSCC cell lines. External irradiation was the most consistently efficient stimulus, and corresponding TLR3 agonists were conveyed in extracellular vesicles. TLR3-stimulating activity was detected in the fluids from all five patients and three mouse tumor grafts. In most cases, this activity was greatly reduced by RNAse pretreatment or TLR3 blocking antibodies. Our data indicate that TLR3 agonists are consistently present in necrotic fluids from HNSCC cells and mainly made of dsRNA fragments. These endogenous agonists may induce TLR3, which might lead to a protumorigenic effect. Regarding methodological aspects, our study demonstrates that direct investigations—including functional testing—can be performed on necrotic fluids from patient tumors. [ABSTRACT FROM AUTHOR]