Cascade Enzymes Confined in DNA Nanoanchors for Antitumor Therapy.

Cascade-enzyme reaction systems have emerged as promising tools for treating malignant tumors by efficiently converting nutrients into toxic substances. However, the challenges of poor localized retention capacity and utilization of highly active enzymes often result in extratumoral toxicity and reduced therapeutic efficacy. In this study, we introduced a cell membrane-DNA nanoanchor (DNANA) with a spatially confined cascade enzyme for in vivo tumor therapy. The DNANAs are constructed using a polyvalent cholesterol-labeled DNA triangular prism, ensuring high stability in cell membrane attachment. Glucose oxidase (GOx) and horseradish peroxidase (HRP), both modified with streptavidin, are precisely confined to biotin-labeled DNANAs. Upon intratumoral injection, DNANA enzymes efficiently colonize the tumor site through cellular membrane engineering strategies, significantly reducing off-target enzyme leakage and the associated risks of extratumoral toxicity. Furthermore, DNANA enzymes demonstrated effective cancer therapy in vitro and in vivo by depleting glucose and producing highly cytotoxic hydroxyl radicals in the vicinity of tumor cells. This membrane-engineered cascade-enzyme reaction system presents a conceptual approach to tumor treatment.

Harnessing Spatiotemporal-Specific Tumorous Exosome Dynamics: Ultra-Sensitive Lanthanide Luminescence Detection Strategy Enabled by Exosomal Membrane Engineering for Melanoma Immunotherapy Monitoring.

Focused on the newly secreted tumorous exosomes during melanoma immunotherapy, this work has pioneered an ultra-sensitive spatiotemporal-specific exosome detection strategy, leveraging advanced exosomal membrane engineering techniques. The proposed strategy harnesses the power of amplified lanthanide luminescence signals on these exosomes, enabling precise and real-time monitoring of the efficacy of melanoma immunotherapy. The methodology comprises two pivotal steps. Initially, Ac4ManNAz-associated metabolic labeling is employed to evolve azide groups onto the membranes of newly secreted exosomes with remarkable selectivity. These azide groups serve as versatile clickable artificial tags, enabling the precise identification of melanoma exosomes emerging during immunotherapy. Subsequently, lanthanide-nanoparticle-functionalized polymer chains are controllably grafted onto the exosome surfaces through click chemistry and in situ Fenton-RAFT polymerization, serving as robust signal amplifiers. When integrated with time-resolved fluorescence detection, this strategy yields detection signals with an exceptionally high signal-to-noise ratio, enabling ultra-sensitive detection of PD-L1 antigen expression levels on the spatiotemporal-specific exosomes. The detection strategy boasts a wide linear concentration range spanning from 1.7 × 104 to 1.7 × 109 particles/mL, with a remarkable theoretical detection limit of 1.28 × 103 particles/mL. The remarkable enhancements in detection sensitivity and accuracy facilitate the evaluation of the efficacy of immunotherapeutic interventions in the mouse B16 melanoma model, notably revealing a substantial disparity in PD-L1 levels between immunotherapy-treated and untreated groups (P < 0.01) and further emphasizing the cumulative therapeutic effect that intensifies with repeated treatments (P < 0.001).

Highly flexible cell membranes are the key to efficient production of lipophilic compounds.

Lipophilic compounds have a variety of positive effects on human physiological functions and exhibit good effects in the prevention and treatment of clinical diseases. This has led to significant interest in the technical applications of synthetic biology for the production of lipophilic compounds. However, the strict selective permeability of the cell membrane and the hydrophobic nature of lipophilic compounds pose significant challenges to their production. During fermentation, lipophilic compounds tend to accumulate within cell membrane compartments rather than being secreted extracellularly. The toxic effects of excessive lipophilic compound accumulation can threaten cell viability, while the limited space within the cell membrane restricts further increases in production yield. Consequently, to achieve efficient production of lipophilic compounds, research is increasingly focused on constructing robust and multifunctional microbial cell factories. Utilizing membrane engineering techniques to construct highly flexible cell membranes is considered an effective strategy to break through the upper limit of lipophilic compound production. Currently, there are two main approaches to cell membrane modification: constructing artificial storage compartments for lipophilic compounds and engineering the cell membrane structure to facilitate product outflow. This review summarizes recent cell membrane engineering strategies applied in microbial cell factories for the production of liposoluble compounds, discussing the challenges and future prospects. These strategies enhance membrane flexibility and effectively promote the production of liposoluble compounds.

Cell Membrane Engineered Polypeptide Nanonets Mimicking Macrophage Aggregates for Enhanced Antibacterial Treatment.

Drug-resistant bacterial infections and their lipopolysaccharide-related inflammatory complications continue to pose significant challenges in traditional treatments. Inspired by the rapid initiation of resident macrophages to form aggregates for efficient antibacterial action, this study proposes a multifunctional and enhanced antibacterial strategy through the construction of novel biomimetic cell membrane polypeptide nanonets (R-DPB-TA-Ce). The design involves the fusion of end-terminal lipidated polypeptides containing side-chain cationic boronic acid groups (DNPLBA) with cell membrane intercalation engineering (R-DPB), followed by coordination with the tannic acid-cerium complex (TA-Ce) to assemble into a biomimetic nanonet through boronic acid-polyphenol-metal ion interactions. In addition to the ability of RAW 264.7 macrophages cell membrane components' (R) ability to neutralize lipopolysaccharide (LPS), R-DPB-TA-Ce demonstrated enhanced capture of bacteria and its LPS, leveraging nanoconfinement-enhanced multiple interactions based on the boronic acid-polyphenol nanonets skeleton combined with polysaccharide. Utilizing these advantages, indocyanine green (ICG) is further employed as a model drug for delivery, showcasing the exceptional treatment effect of R-DPB-TA-Ce as a new biomimetic assembled drug delivery system in antibacterial, anti-inflammatory, and wound healing promotion. Thus, this strategy of mimicking macrophage aggregates is anticipated to be further applicable to various types of cell membrane engineering for enhanced antibacterial treatment.

Development of a Portable Cell-Based Biosensor for the Ultra-Rapid Screening for Boscalid Residues in Lettuce.

Fungal plant pathogens have posed a significant threat to crop production. However, the large-scale application of pesticides is associated with possible risks for human health and the environment. Boscalid is a widely used fungicide, consistently implemented for the management of significant plant pathogens. Conventionally, the detection and determination of boscalid residues is based on chromatographic separations. In the present study, a Bioelectric Recognition Assay (BERA)-based experimental approach combined with MIME technology was used, where changes in the electric properties of the membrane-engineering cells with anti-boscalid antibodies were recorded in response to the presence of boscalid at different concentrations based on the maximum residue level (MRL) for lettuce. The membrane-engineering Vero cells with 0.5 µg/mL of antibody in their surface were selected as the best cell line in combination with the lowest antibody concentration. Furthermore, the biosensor was tested against another fungicide in order to prove its selectivity. Finally, the BERA cell-based biosensor was able to detect the boscalid residue, below and above the MRL, in spiked lettuce leaf extracts in an entirely distinct and reproducible manner. This study indicates that the BERA-based biosensor, after further development and optimization, could be used for the routine, high-throughput detection of boscalid residue in lettuce, and not only that.

Transcending membrane barriers: advances in membrane engineering to enhance the production capacity of microbial cell factories.

Microbial cell factories serve as pivotal platforms for the production of high-value natural products, which tend to accumulate on the cell membrane due to their hydrophobic properties. However, the limited space of the cell membrane presents a bottleneck for the accumulation of these products. To enhance the production of intracellular natural products and alleviate the burden on the cell membrane caused by product accumulation, researchers have implemented various membrane engineering strategies. These strategies involve modifying the membrane components and structures of microbial cell factories to achieve efficient accumulation of target products. This review summarizes recent advances in the application of membrane engineering technologies in microbial cell factories, providing case studies involving Escherichia coli and yeast. Through these strategies, researchers have not only improved the tolerance of cells but also optimized intracellular storage space, significantly enhancing the production efficiency of natural products. This article aims to provide scientific evidence and references for further enhancing the efficiency of similar cell factories.

Enhancing Escherichia coli abiotic stress resistance through ornithine lipid formation.

Escherichia coli is a common host for biotechnology and synthetic biology applications. During growth and fermentation, the microbes are often exposed to stress conditions, such as variations in pH or solvent concentrations. Bacterial membranes play a key role in response to abiotic stresses. Ornithine lipids (OLs) are a group of membrane lipids whose presence and synthesis have been related to stress resistance in bacteria. We wondered if this stress resistance could be transferred to bacteria not encoding the capacity to form OLs in their genome, such as E. coli. In this study, we engineered different E. coli strains to produce unmodified OLs and hydroxylated OLs by expressing the synthetic operon olsFC. Our results showed that OL formation improved pH resistance and increased biomass under phosphate limitation. Transcriptome analysis revealed that OL-forming strains differentially expressed stress- and membrane-related genes. OL-producing strains also showed better growth in the presence of the ionophore carbonyl cyanide 3-chlorophenylhydrazone (CCCP), suggesting reduced proton leakiness in OL-producing strains. Furthermore, our engineered strains showed improved heterologous violacein production at phosphate limitation and also at low pH. Overall, this study demonstrates the potential of engineering the E. coli membrane composition for constructing robust hosts with an increased abiotic stress resistance for biotechnology and synthetic biology applications. KEY POINTS: • Ornithine lipid production in E. coli increases biomass yield under phosphate limitation. • Engineered strains show an enhanced production phenotype under low pH stress. • Transcriptome analysis and CCCP experiments revealed reduced proton leakage.

Cell-Surface Binding of DNA Nanostructures for Enhanced Intracellular and Intranuclear Delivery.

DNA nanostructures (DNs) have found increasing use in biosensing, drug delivery, and therapeutics because of their customizable assembly, size and shape control, and facile functionalization. However, their limited cellular uptake and nuclear delivery have hindered their effectiveness in these applications. Here, we demonstrate the potential of applying cell-surface binding as a general strategy to enable rapid enhancement of intracellular and intranuclear delivery of DNs. By targeting the plasma membrane via cholesterol anchors or the cell-surface glycocalyx using click chemistry, we observe a significant 2 to 8-fold increase in the cellular uptake of three distinct types of DNs that include nanospheres, nanorods, and nanotiles, within a short time frame of half an hour. Several factors are found to play a critical role in modulating the uptake of DNs, including their geometries, the valency, positioning and spacing of binding moieties. Briefly, nanospheres are universally preferable for cell surface attachment and internalization. However, edge-decorated nanotiles compensate for their geometry deficiency and outperform nanospheres in both categories. In addition, we confirm the short-term structural stability of DNs by incubating them with cell medium and cell lysate. Further, we investigate the endocytic pathway of cell-surface bound DNs and reveal that it is an interdependent process involving multiple pathways, similar to those of unmodified DNs. Finally, we demonstrate that cell-surface attached DNs exhibit a substantial enhancement in the intranuclear delivery. Our findings present an application that leverages cell-surface binding to potentially overcome the limitations of low cellular uptake, which may strengthen and expand the toolbox for effective cellular and nuclear delivery of DNA nanostructure systems.

CXCR4-Targeted Macrophage-Derived Biomimetic Hybrid Vesicle Nanoplatform for Enhanced Cancer Therapy through Codelivery of Manganese and Doxorubicin.

Immune-cell-derived membranes have garnered significant attention as innovative delivery modalities in cancer immunotherapy for their intrinsic immune-modulating functionalities and superior biocompatibilities. Integrating additional parental cell membranes or synthetic lipid vesicles into cellular vesicles can further potentiate their capacities to perform combinatorial pharmacological activities in activating antitumor immunity, thus providing insights into the potential of hybrid cellular vesicles as versatile delivery vehicles for cancer immunotherapy. Here, we have developed a macrophage-membrane-derived hybrid vesicle that has the dual functions of transporting immunotherapeutic drugs and shaping the polarization of tumor-associated macrophages for cancer immunotherapy. The platform combines M1 macrophage-membrane-derived vesicles with CXCR4-binding-peptide-conjugated liposomes loaded with manganese and doxorubicin. The hybrid nanovesicles exhibited remarkable macrophage-targeting capacity through the CXCR4-binding peptide, resulting in enhanced macrophage polarization to the antitumoral M1 phenotype characterized by proinflammatory cytokine release. The manganese/doxorubicin-loaded hybrid vesicles in the CXCR4-expressing tumor cells evoked potent cancer cytotoxicity, immunogenic cell death of tumor cells, and STING activation. Moreover, cotreatment with manganese and doxorubicin promoted dendritic cell maturation, enabling effective tumor growth inhibition. In murine models of CT26 colon carcinoma and 4T1 breast cancer, intravenous administration of the manganese/doxorubicin-loaded hybrid vesicles elicited robust tumor-suppressing activity at a low dosage without adverse systemic effects. Local administration of hybrid nanovesicles also induced an abscessive effect in a bilateral 4T1 tumor model. This study demonstrates a promising biomimetic manganese/doxorubicin-based hybrid nanovesicle platform for effective cancer immunotherapy tailored to the tumor microenvironment, which may offer an innovative approach to combinatorial immunotherapy.

Securing LYTAC with Logic-Identification System for Cancer Cell-Selective Membrane Protein Degradation.

Lysosome-targeting chimera (LYTAC) links proteins of interest (POIs) with lysosome-targeting receptors (LTRs) to achieve membrane protein degradation, which is becoming a promising therapeutic modality. However, cancer cell-selective membrane protein degradation remains a big challenge considering expressions of POIs in both cancer cells and normal cells, as well as broad tissue distribution of LTRs. Here a logic-identification system is designed, termed Logic-TAC, based on cell membrane-guided DNA calculations to secure LYTAC selectively for cancer cells. Logic-TAC is designed as a duplex DNA structure, with both POI and LTR recognition regions sealed to avoid systematic toxicity during administration. MCF-7 and MCF-10A are chosen as sample cancer cell and normal cell respectively. As input 1 for logic-identification, membrane proteins EpCAM, which is highly expressed by MCF-7 but barely by MCF-10A, reacts with Logic-TAC to expose POI recognition region. As input 2 for logic-identification, Logic-TAC binds to POI, membrane protein MUC1, to expose LTR recognition region. As output, MUC1 is connected to LTR and degraded via lysosome pathway selectively for cancer cell MCF-7 with little side effect on normal cell MCF-10A. The logic-identification system also demonstrated satisfactory in vivo therapeutic results, indicating its promising potential in precise targeted therapy.

Spatiotemporal Regulation and Transport Engineering for Sustainable Production of Geraniol in Candida glycerinogenes.

Geraniol is an attractive natural monoterpene with significant industrial and commercial value in the fields of pharmaceuticals, condiments, cosmetics, and bioenergy. The biosynthesis of monoterpenes suffers from the availability of key intermediates and enzyme-to-substrate accessibility. Here, we addressed these challenges in Candida glycerinogenes by a plasma membrane-anchoring strategy and achieved sustainable biosynthesis of geraniol using bagasse hydrolysate as substrate. On this basis, a remarkable 2.4-fold improvement in geraniol titer was achieved by combining spatial and temporal modulation strategies. In addition, enhanced geraniol transport and modulation of membrane lipid-associated metabolism effectively promoted the exocytosis of toxic monoterpenes, significantly improved the resistance of the engineered strain to monoterpenes and improved the growth of the strains, resulting in geraniol yield up to 1207.4 mg L-1 at shake flask level. Finally, 1835.2 mg L-1 geraniol was obtained in a 5 L bioreactor using undetoxified bagasse hydrolysate. Overall, our study has provided valuable insights into the plasma membrane engineering of C. glycerinogenes for the sustainable and green production of valuable compounds.

Unveiling the Potential of Pt Nanoparticle-Decorated PEDOT:PSS Membranes for Efficient Gas Separation.

In the dynamic landscape of industrial processes, membrane technology offers a paradigm shift beyond energy-intensive separation techniques, exemplifying a progressive leap toward sustainability. In this regard, highly flexible and uniform poly(3,4-ethylenedioxythiophene)polystyrenesulfonate (PEDOT:PSS)-engineered membranes at a reduced thickness have been fabricated on track-etched poly(ethylene terephthalate) (PET) substrates. The membranes were functionalized and embedded with platinum nanoparticles (Pt NPs) having a higher affinity toward H2 gas. The materials and fabricated membranes were characterized by using high-resolution transmission electron microscopy (HRTEM) and field emission scanning electron microscopy (FESEM) techniques for morphological and structural analysis. FTIR and Raman characterizations were performed to study the characteristic bonds. The uniformity and quantification of Pt nanoparticle binding were tested through inductively coupled plasma mass spectrometry (ICP-MS) studies and FESEM with EDS mapping. The gas separation performance was studied using H2, N2, and CO2 gases in pure and mixed (H2/CO2 in 50:50) states. It was observed that the modified membrane showed a 116% increment in H2 permeability and 82 and 107% increment in H2/CO2 and H2/N2 selectivity values with pure gas, while a 121% increment in H2 permeability and 156% increment in H2/CO2 selectivity using mixed gas. The separation performance in pure and mixed gas states with repeated experiments conspicuously highlighted their prospective viability as prime contenders for gas separation applications.

Improved Membrane Permeability via Hypervesiculation for In Situ Recovery of Lycopene in Escherichia coli.

Lycopene biosynthesis is frequently hampered by downstream processing hugely due to its inability to be secreted out from the producing chassis. Engineering cell factories can resolve this issue by secreting this hydrophobic compound. A highly permeable E. coli strain was developed for a better release rate of lycopene. Specifically, the heterologous mevalonate pathway and crtEBI genes from Corynebacterium glutamicum were overexpressed in Escherichia coli BL21 (DE3) for lycopene synthesis. To ensure in situ lycopene production, murein lipoprotein, lipoprotein NlpI, inner membrane permease protein, and membrane-anchored protein in TolA-TolQ-TolR were deleted for improved membrane permeability. The final strain, LYC-8, produced 438.44 ± 8.11 and 136.94 ± 1.94 mg/L of extracellular and intracellular lycopene in fed-batch fermentation. Both proteomics and lipidomics analyses of secreted outer membrane vesicles were perfect indicators of hypervesiculation. Changes in the ratio of saturated fatty acids, unsaturated fatty acids, and cyclopropane fatty acids coupled with the branching and acyl chain lengths altered the membrane fatty acid composition. This ensured membrane fluidity and permeability for in situ lycopene release. The combinatorial deletion of these genes altered the cellular morphology. The structural and morphological changes in cell shape, size, and length were associated with changes in the mechanical strength of the cell envelope. The enhanced lycopene production and secretion mediated by improved membrane permeability established a cell lysis-free system for an efficient releasing rate and downstream processing, demonstrating the importance of vesicle-associated membrane permeability in efficient lycopene production.

Improving acid resistance of Escherichia coli base on the CfaS-mediated membrane engineering strategy derived from extreme acidophile.

Industrial microorganisms used for the production of organic acids often face challenges such as inhibited cell growth and reduced production efficiency due to the accumulation of acidic metabolites. One promising way for improving the acid resistance of microbial cells is to reconstruct their membranes. Herein, the overexpression of cfa2 from extreme acidophile endowed E. coli with high-performance on resistance to the acid stress. The engineered strain M1-93-Accfa2, constructed by CRISPR/Cas9-mediated chromosome integration, also exhibited a significantly higher resistance to severe acid stress. The analysis of fatty acid profiles indicated that the proportion of Cy-19:0 in the cell membrane of M1-93-Accfa2 increased by 5.26 times compared with the control, while the proportion of C18:1w9c decreased by 5.81 times. Correspondingly, the permeability and fluidity of the membrane decreased significantly. HPLC analysis demonstrated that the contents of intracellular glutamic acid, arginine, methionine and aspartic acid of M1-93-Accfa2 were 2.59, 2.04, 22.07 and 2.65 times that of the control after environmental acidification, respectively. Meanwhile, transmission electron microscopy observation indicated that M1-93-Accfa2 could maintain a plumper cell morphology after acid stimulation. M1-93-Accfa2 also exhibited higher-performance on the resistance to organic acids, especially succinic acid stress. These results together demonstrated the great potential of M1-93-Accfa2 constructed here in the production of organic acids.

Engineering membrane architecture for biotechnological applications.

Cellular membranes, predominantly described as a dynamic bilayer, are composed of different lipids, transmembrane proteins, and carbohydrates. Most research on biological membranes focuses on the identification, characterization, and mechanistic aspects of their different components. These studies provide a fundamental understanding of membrane structure, function, and dynamics, establishing a basis for the development of membrane engineering strategies. To date, approaches in this field concentrate on membrane adaptation to harsh conditions during industrial fermentation, which can be caused by temperature, osmotic, or organic solvent stress. With advances in the field of metabolic engineering and synthetic biology, recent breakthroughs include proof of concept microbial production of essential medicines, such as cannabinoids and vinblastine. However, long pathways, low yields, and host adaptation continue to pose challenges to the efficient scale up production of many important compounds. The lipid bilayer is profoundly linked to the activity of heterologous membrane-bound enzymes and transport of metabolites. Therefore, strategies for improving enzyme performance, facilitating pathway reconstruction, and enabling storage of products to increase the yields directly involve cellular membranes. At the forefront of membrane engineering research are re-emerging approaches in lipid research and synthetic biology that manipulate membrane size and composition and target lipid profiles across species. This review summarizes engineering strategies applied to cellular membranes and discusses the challenges and future perspectives, particularly with regards to their applications in host engineering and bioproduction.

Metabolic engineering of Mannheimia succiniciproducens for malic acid production using dimethylsulfoxide as an electron acceptor.

Microbial production of various TCA intermediates and related chemicals through the reductive TCA cycle has been of great interest. However, rumen bacteria that naturally possess strong reductive TCA cycle have been rarely studied to produce these chemicals, except for succinic acid, due to their dependence on fumarate reduction to transport electrons for ATP synthesis. In this study, malic acid (MA), a dicarboxylic acid of industrial importance, was selected as a target chemical for mass production using Mannheimia succiniciproducens, a rumen bacterium possessing a strong reductive branch of the TCA cycle. The metabolic pathway was reconstructed by eliminating fumarase to prevent MA conversion to fumarate. The respiration system of M. succiniciproducens was reconstructed by introducing the Actinobacillus succinogenes dimethylsulfoxide (DMSO) reductase to improve cell growth using DMSO as an electron acceptor. Also, the cell membrane was engineered by employing Pseudomonas aeruginosa cis-trans isomerase to enhance MA tolerance. High inoculum fed-batch fermentation of the final engineered strain produced 61 g/L of MA with an overall productivity of 2.27 g/L/h, which is the highest MA productivity reported to date. The systems metabolic engineering strategies reported in this study will be useful for developing anaerobic bioprocesses for the production of various industrially important chemicals.

Efficient De Novo Biosynthesis of Heme by Membrane Engineering in Escherichia coli.

Heme is of great significance in food nutrition and food coloring, and the successful launch of artificial meat has greatly improved the application of heme in meat products. The precursor of heme, 5-aminolevulinic acid (ALA), has a wide range of applications in the agricultural and medical fields, including in the treatment of corona virus disease 2019 (COVID-19). In this study, E. coli recombinants capable of heme production were developed by metabolic engineering and membrane engineering. Firstly, by optimizing the key genes of the heme synthesis pathway and the screening of hosts and plasmids, the recombinant strain EJM-pCD-AL produced 4.34 ± 0.02 mg/L heme. Then, the transport genes of heme precursors CysG, hemX and CyoE were knocked out, and the extracellular transport pathways of heme Dpp and Ccm were strengthened, obtaining the strain EJM-ΔCyoE-pCD-AL that produced 9.43 ± 0.03 mg/L heme. Finally, fed-batch fermentation was performed in a 3-L fermenter and reached 28.20 ± 0.77 mg/L heme and 303 ± 1.21 mg/L ALA. This study indicates that E. coli recombinant strains show a promising future in the field of heme and ALA production.

Multiplexed Detection of Molecular Interactions with DNA Origami Engineered Cells in 3D Collagen Matrices.

The interactions of cells with signaling molecules present in their local microenvironment maintain cell proliferation, differentiation, and spatial organization and mediate progression of diseases such as metabolic disorders and cancer. Real-time monitoring of the interactions between cells and their extracellular ligands in a three-dimensional (3D) microenvironment can inform detection and understanding of cell processes and the development of effective therapeutic agents. DNA origami technology allows for the design and fabrication of biocompatible and 3D functional nanodevices via molecular self-assembly for various applications including molecular sensing. Here, we report a robust method to monitor live cell interactions with molecules in their surrounding environment in a 3D tissue model using a microfluidic device. We used a DNA origami cell sensing platform (CSP) to detect two specific nucleic acid sequences on the membrane of B cells and dendritic cells. We further demonstrated real-time detection of biomolecules with the DNA sensing platform on the surface of dendritic cells in a 3D microfluidic tissue model. Our results establish the integration of live cells with membranes engineered with DNA nanodevices into microfluidic chips as a highly capable biosensor approach to investigate subcellular interactions in physiologically relevant 3D environments under controlled biomolecular transport.

Engineered Cell Membrane-Derived Nanocarriers: The Enhanced Delivery System for Therapeutic Applications.

There has been a rapid development of biomimetic platforms using cell membranes as nanocarriers to camouflage nanoparticles for enhancing bio-interfacial capabilities. Various sources of cell membranes have been explored for natural functions such as circulation and targeting effect. Biomedical applications of cell membranes-based delivery systems are expanding from cancer to multiple diseases. However, the natural properties of cell membranes are still far from achieving desired functions and effects as a nanocarrier platform for various diseases. To obtain multi-functionality and multitasking in complex biological systems, various functionalized modifications of cell membranes are being developed based on physical, chemical, and biological methods. Notably, many research opportunities have been initiated at the interface of multi-technologies and cell membranes, opening a promising frontier in therapeutic applications. Herein, the current exploration of natural cell membrane functionality, the design principles for engineered cell membrane-based delivery systems, and the disease applications are reviewed, with a special focus on the emerging strategies in engineering approaches.

DNA-Based Molecular Engineering of the Cell Membrane.

The cell membrane serves as a barrier and gatekeeper to regulate the cellular transportation of substances and information. It plays a significant role in protecting the cell from the extracellular environment, maintaining intracellular homeostasis, and regulating cellular function and behaviors. The capability to engineer the cell membrane with functional modules that enable dynamic monitoring and manipulating the cell-surface microenvironment would be critical for studying molecular mechanisms underlying various biological processes. To meet this goal, DNA, with intrinsic advantages of high versatility, programmability, and biocompatibility, has gained intense attention as a molecular tool for cell-surface engineering. The past three decades have witnessed the rapid advances of diverse nucleic acid materials, including functional nucleic acids (FNAs), dynamic DNA circuits, and exquisite DNA nanostructures. In this mini review, we have summarized the recent progress of DNA technology for cell membrane engineering, particularly focused on their applications for molecular sensing and imaging, precise cell identification, receptor activity regulation, and artificial membrane structures. Furthermore, we discussed the challenge and outlook on using nucleic acid materials in this specific research area.