ACS Nano
● American Chemical Society (ACS)
Preprints posted in the last 90 days, ranked by how well they match ACS Nano's content profile, based on 113 papers previously published here. The average preprint has a 0.09% match score for this journal, so anything above that is already an above-average fit.
Velazquez, S.; Thompson, W.; Ashkarran, A. A.
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The protein corona (PC), a layer of biomolecules that adsorbs onto nanoparticles (NPs) surfaces upon exposure to biological fluids, plays a key role in defining the biological identity and performance of nanomaterials. However, most current analytical approaches rely on pooled measurements of PC-coated NPs and therefore lack the resolution needed to detect subtle heterogeneity in PC composition, potentially masking important differences in NPs biological identity. Here, we used a high-sensitivity magnetic levitation (MagLev) platform capable of resolving extremely small density differences among nominally identical PC-coated NPs, enabling fractionation of particles based on subtle variations in PC composition. Compared with conventional standard MagLev systems (density resolution [~]10-3 g/cm3), the high-sensitivity MagLev improves density sensitivity by up to three orders of magnitude, allowing discrimination of density differences as small as 10-5 g/cm3. Using this approach, PC-coated NPs were separated along the MagLev column into multiple fractions corresponding to distinct density populations. Subsequent proteomic analysis across the extracted fractions identified more than 500 proteins and revealed a structured but continuous redistribution of protein composition across the column, including fraction-dependent differences in protein abundance, overlap, and biological identity. In particular, the fraction series captured hidden heterogeneity among nominally identical PC-coated NPs, with upper fractions retaining relatively stronger extracellular/plasma-associated signatures and lower fractions showing increasing representation of structural, membrane-associated, cytoskeletal, and metabolic proteins. These findings demonstrate that PC formation is intrinsically heterogeneous even on identical NPs and this heterogeneity is largely missed by conventional pooled analysis. High-sensitivity MagLev provides a simple, label-free framework for resolving PC heterogeneity and offers a new analytical approach for studying NP-biomolecule interactions, with important implications for nanomedicine design, biomarker discovery, and the clinical translation of NP-based systems. TOC O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=96 SRC="FIGDIR/small/727410v1_ufig1.gif" ALT="Figure 1"> View larger version (41K): org.highwire.dtl.DTLVardef@155ad62org.highwire.dtl.DTLVardef@1ea3e3dorg.highwire.dtl.DTLVardef@19c40ceorg.highwire.dtl.DTLVardef@162ca8d_HPS_FORMAT_FIGEXP M_FIG C_FIG
Grumelot, S.; Mohammed, N.; Yerima, G.; Colonrosado, J.; Sadeghi, S. A.; Fang, F.; Hilsen, K.; Shango, B.; Saei, A. A.; Murray, A. M.; Mitchell, M. J.; Borhan, B.; Sun, L.; Vali, H.; Mofrad, M.; Whitehead, K.; Mahmoudi, M.
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The protein corona influences the in vivo biodistribution of ionizable lipid nanoparticles (LNPs) in nucleic acid delivery, yet its structural architecture remains poorly defined. Using cryo-transmission electron microscopy, we visualized LNP-protein interactions in their native state. We show that, unlike the discrete "fuzzy" shells observed on hard nanoparticles, LNPs displayed no peripheral protein shell. Instead, controlled incubation and competitive "dual-particle" assays, supported by molecular dynamics simulations, indicate that LNP membranes undergo localized thickening and electron-dense remodeling consistent with lipoprotein integration rather than surface adsorption. Similar features were observed in extracellular vesicles, suggesting this behavior is shared among lipid-based carriers, and proteomic analysis identified apolipoproteins as the dominant associated proteins. Together, these findings support a model in which the biological identity of LNPs arises through membrane remodeling rather than shell-like adsorption, and provide a framework for the rational design of targeted nanomedicines. TOC Graphic O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=138 SRC="FIGDIR/small/695162v2_ufig1.gif" ALT="Figure 1"> View larger version (79K): org.highwire.dtl.DTLVardef@5275d3org.highwire.dtl.DTLVardef@1b59ae4org.highwire.dtl.DTLVardef@1cc290eorg.highwire.dtl.DTLVardef@9b7bfb_HPS_FORMAT_FIGEXP M_FIG C_FIG
El-Helou, A. J.; Liu, Y.; Khosravi, F.; Chen, C.; Yan, C. H. W.; Lockrey, M.; Ruan, J.; Liu, Z.; Reece, P. J.; Zhu, Y.
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The accurate quantification of biological nanoparticles, such as small extracellular vesicles (sEVs), is fundamentally hindered by a resolution-coincidence trade-off in digital assays. While physical confinement can isolate single particles, conventional optical readouts remain diffraction-limited, causing multi-particle occupancy to be miscounted as single events and thereby restricting the analytical dynamic range. Here, we report a nanoplasmonic platform that overcomes this limit by introducing a geometry-defined interface that uniquely unifies nanoscale compartmentalisation and near-field-assisted super-resolution imaging. Utilising a gold plasmonic nanohole array, the strict geometric periodicity of the lattice simultaneously serves as a template for single-vesicle confinement and a deterministic grid that generates an array of localised surface plasmon resonance near-field hotspots. This position-deterministic illumination pattern imposes known geometric priors on the excitation field, shifting high-spatial-frequency information into the detectable bandwidth to achieve sub-100 nm lateral resolution. This dual-purpose geometric determinism enables high-fidelity digital readout of individual vesicles with significantly fewer sub-images than stochastic, speckle-based metasurface structured illumination microscopy approaches. The assay achieves an analytical limit of detection of 143 sEVs/{micro}L, matching the performance of state-of-the-art single-EV counting technologies. It successfully differentiates distinct sEV subpopulations based on surface biomarker expression, establishing a clear pathway for future clinical liquid biopsy applications. By replacing stochastic loading and illumination with geometric design, this work establishes a robust framework for precise vesicle interrogation with broad implications for emerging translational applications and fundamental biology.
Li, J.; Liu, N.; Zhang, D.; Lee, H. J.
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Although microplastics and nanoplastics (MP/NP) are pervasive environmental contaminants, our understanding of cellular toxicity remains incomplete, as adverse effects are often attributed to long-term intracellular accumulation, while the spatiotemporal onset of cellular damage remains poorly defined. Here, we employ chemical-bond-selective stimulated Raman scattering (SRS) microscopy and cell models that decouple continuous exposure from intracellular retention to directly visualize clinically derived MP/NP-cell interactions. Cellular stress occurs primarily during MP/NP exposure, accompanied by alterations in lipid droplet (LD) composition. In contrast, following extracellular removal, intracellularly retained MP/NP become largely inert, with recovery of lipid metabolism and cellular functions. Lipidomics identifies arachidonic acid (AA) as a key dysregulated metabolite, and SRS imaging further reveals transient, spatially confined AA enrichment in MP/NP-proximal LDs during uptake. Importantly, phospholipid coating of MP/NP attenuates LD alterations and cytotoxicity while preserving particle internalization, establishing uptake-driven metabolic stress, rather than long-term intracellular retention, as primary source of MP/NP-induced damage.
Zhang, C.; choudhury, s.; jansen, k.; balkenhol, j.; Heinze, K.
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High-quality cellular imaging, especially in live cells, remains constrained by the trade-off among signal-to-noise ratio, phototoxicity, and instrumentation complexity. Here, we report a scalable plasmonic metasurface that generates a spatially ordered array of fluorescence-enhancing near-field hotspots and enables self-supervised denoised, cellular imaging with improved feature readability on a conventional wide-field microscope. The registered hotspot lattice serves as a physics-derived functional prior that identifies where fluorescence amplification is physically grounded and steers neural-network training accordingly, reducing reliance on paired ground truth, large external pretrained models, or extensive supervised datasets. We demonstrate two labeling-density-dependent operating regimes: dense labeling for cytoskeleton structural imaging and sparse labeling for multiplexed sensing of plasma-membrane-associated dynamics across the hotspot array. Our work unites scalable nanophotonic hardware and self-supervised computational imaging into a practical platform for structural bioimaging and on-chip live-cell biosensing under simple wide-field imaging conditions.
Journaux-Duclos, J.; Bejko, M.; Clerc, P.; Al Yaman, Y.; Abdelhamid, A. G. A.; Ballon, G.; Bousquet, C.; Carrey, J.; Mornet, S.; Sandre, O.; Gigoux, V.
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The first and critical reaction in magnetic hyperthermia to induce the death of cancer cells is the production of ROS (reactive oxygen species). We previously showed that it is possible to specifically deliver iron oxide magnetic nanoparticles (IONPs) in the lysosomes of cancer cells and eradicate them by targeted magnetic intra-lysosomal hyperthermia (MILH) via the application of a high frequency alternating magnetic field (AMF) without macroscopic temperature elevation. The mechanism involves a local temperature elevation at the IONPs surface which enhances the ROS production through the Fenton reaction; ROS then peroxide the proteins and lipids of the lysosomal membrane, inducing its permeabilization and leading to lysosomal enzymes release and cell death. Fe ions, critical to produce ROS in MILH, were assumed to be released by IONPs. We thus developed PEGylated multi-cores IONPs called NanoFlowers (NF@PEG) presenting or not a SiO2 shell (NF@SiO2@PEG), the later preventing the Fe3+ release from IONPs. NF@PEG released Fe ions and produced ROS production in vitro, in acidic medium mimicking lysosome upon AMF exposure, whereas NF@SiO2@PEG did not. Surprisingly, both nanoparticles increased the ROS production in cells, induced lysosome permeabilization and cell death, and slowed down the proliferation of cancer cells with the same efficacy, upon AMF application, indicating that MILH was efficient in absence of Fe3+ release from IONPs. In contrast, Ferristatin-II, an iron uptake inhibitor, prevented the ROS production and cell death in MILH induced by both IONPs, elucidating the role of endogenous iron cations responsible for the ROS production ROS in MILH to kill cancer cells.
Ruan, L.; Manko, H.; Gresil, Q.; Aleman-Castaneda, L. A.; Meras, M.; Sebastian, F.; Flavel, B.; Zaumseil, J.; Groc, L.; Brasselet, S.; Tondusson, M.; Cognet, L.
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Transport in complex biological tissues is governed by local rheological heterogeneity at the nanoscale, yet probing such environments deep inside living systems remains challenging. Here, we introduce an orientation-sensitive single-particle tracking (SPoT) approach that simultaneously resolves translational and rotational dynamics of individual carbon nanotubes deep within biological tissue. By exploiting the intrinsic dipole-like emission and shortwave infrared luminescence of carbon nanotubes enhanced through the incorporation of quantum color-centers our method enables long-duration tracking with high signal-to-noise ratio in optically dense environments. Crucially, the length of these nanotubes can be precisely shortened down to a few tens of nanometers to adapt to diffusion environmental dimensions, further optimizing the tracking applicability. SPoT of single carbon nanotubes provides access to relative changes in local viscosity, steric constraints, and environmental anisotropy. When applied to the brain extracellular space, SPoT demonstrates that local variations in the translational and rotational diffusion of tracers are heterogeneous and not systematically correlated. This allows to disentangle the local effects of viscosity and spatial tortuosity within the brain extracellular space, which are distinct features that would otherwise remain undetected through translational diffusion analysis alone. By enabling combined translational and rotational tracking of nano-emitters over unprecedented depths and timescales, this work establishes a new framework for probing nanoscale transport and rheological heterogeneity in intact biological tissues and more generally in complex diffusive environments.
Velazquez, S.; Juber, M.; Brindley, D.; Thakur, A.; Anasoori, B.; Lau, E.; Ashkarran, A. A.
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The protein corona (PC) that forms on the surface of nanomaterials upon contact with biological fluids provides a molecular snapshot of the hosts physiological and pathological state. Here, we investigate two-dimensional (2D) titanium carbide (Ti3C2Tx) MXene nanosheets as nanobiointerfaces for capturing Alzheimers disease (AD)-associated plasma protein signatures. Ti3C2Tx MXene flakes were incubated with plasma from clinically diagnosed AD patients and age-matched healthy controls (HC), leading to the formation of Ti3C2Tx MXene-PC complexes. Physicochemical characterization using dynamic light scattering, zeta potential analysis, and transmission electron microscopy revealed disease-dependent changes in hydrodynamic size, surface charge, and PC profile. Proteomic analysis of the isolated PC layers quantified 1,611 proteins without prior fractionation, demonstrating effective enrichment of low-abundance plasma components. Principal component analysis (PCA) revealed consistent separation between AD- and HC-derived Ti3C2Tx MXene-PC proteomes despite inter-individual heterogeneity. Differential abundance analysis identified selective enrichment of heterogeneous nuclear ribonucleoproteins (hnRNPs), annexins, and inflammatory mediators in AD-derived PC, implicating dysregulated RNA metabolism, membrane stress responses, and immune activation, hallmark processes in AD pathology. Our findings demonstrate that Ti3C2Tx MXene-PC interfaces act as selective molecular filters that reshape the detectable plasma proteome, enabling disease-associated molecular phenotyping and establishing a versatile nanointerface-driven framework for uncovering AD-related plasma signatures, providing a foundation for future translational diagnostic development.
Zeng, X.; Zhang, Y.; Wu, C.; Fan, M.; Duan, Q.; Cai, S.; Yasa, I. C.
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Adoptive cell therapy (ACT) remains challenging in solid tumors, where poor tumor infiltration, metabolic heterogeneity, and an immunosuppressive tumor microenvironment (TME) constrain therapeutic efficacy. Here, we developed a magnetically actuated macrophage-based immune microrobot (immunobot) for active solid tumor immunotherapy. Immunobots were constructed by loading bone marrow-derived macrophages (BMDMs) with lipopolysaccharide-modified Janus L1-FePt magnetic microrollers (LMRs), enabling hard-magnetic actuation. Optimized LMR loading supported robust propulsion, retention under flow, and enhanced barrier penetration. LMRs further promoted M1-like polarization through LPS-driven inflammatory activation and FePt-derived labile iron-amplified oxidative stress, with altered iron homeostasis, increased reactive oxygen species (ROS), and enhanced NF-{kappa}B signaling. Immunobots also induced ferroptosis-associated immunogenic cell death in tumor cells. In vivo, magnetically guided immunobots suppressed tumor growth, reprogrammed tumor-associated macrophages (TAMs), promoted dendritic cell maturation, and enhanced CD8 T cell activation. This work establishes a microrobotic immunotherapy platform for active magnetic transport, iron-metabolic regulation, and immune remodeling in solid tumors.
Cai, N.; Guo, W.; Teng, Y.; Lou, Y.; Wong, S.-H.; Naidu, A. S.; Cona, F.; Thei, F.; Chen, T.-H.; Bastings, M.; Radenovic, A.
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Solid-state nanopores offer label-free, real-time single-molecule sensing. However, resolving fast biomolecular transport requires high-bandwidth data acquisition while the intrinsic high-frequency noise limits recovery of informative events. Here we present a hardware-software co-designed nanopore sensing platform that combines wafer-scale low-noise device engineering with deep learning-based signal reconstruction. A low-dielectric SU8 coating on silicon nitride nanopores reduces device capacitance to the pF range and suppresses high-frequency noise by up to 5-fold while maintaining facile, controllable and reproducible fabrication. This extends usable acquisition to 40 MHz and enables capture of fast molecular features. Coupled with a reconstruction model trained on synthetic translocation events embedded in experimentally measured noise, the platform recovers transient sublevels while preserving blockage edges and temporal fidelity. Using engineered DNA molecules carrying dumbbell-like barcodes, we resolve nanometer-scale structural spacings on sub-microsecond timescales, and experimentally quantify translocation dynamics within the sub-10 nanometer regime. Dual-channel measurement on a single nanopore device further demonstrates transferability of the platform by showing robust cross-channel signal reconstruction across distinct baseline noise levels. Our approach provides a general route for reliable recovery of fast event features and may enable more information-rich single-molecule sensing across diverse biomolecular targets.
Rashid, M. H.; Maruf, M. U.; Nations, T.; Megahed, M.; Levitt, D.; Koneru, B.; Ahmad, Z.; Srivastava, I.
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Surface-enhanced Raman scattering (SERS) nanotags provide highly sensitive platforms for in vitro diagnostics but often require complex, disease-specific customization that limits clinical translation. Biomineralization, in which biomolecules mediate inorganic material synthesis, offers a versatile yet underexplored strategy for generating functional SERS nanotags. Here, we demonstrate that biomolecule-directed biomineralization of gold nanoparticles (AuNPs) using amino acids and exosomes generates distinct nano-bio interfacial architectures that encode biomolecular identity into machine learning-resolvable SERS fingerprints through modulation of plasmonic coupling and Raman reporter organization. As a proof-of-concept system, amino acid-biomineralized AuNPs were synthesized using biomolecules with diverse physicochemical properties, including differences in size, polarity, and charge. The resulting nanotags were characterized using UV-Vis spectroscopy, SERS, fluorescence spectroscopy, dynamic light scattering (DLS), and transmission electron microscopy (TEM). Random forest and support vector machine (SVM) models successfully differentiated amino acid-dependent SERS signatures with near-perfect classification performance. Extending this approach to a biologically complex preclinical cancer model, exosome-biomineralized AuNP nanotags were generated using exosomes derived from clinically relevant pediatric patient-derived osteosarcoma and neuroblastoma tumors. Distinct exosome-dependent spectral fingerprints enabled SVM classification with 93.9% accuracy, while Shapley Additive exPlanations (SHAP) and t-distributed stochastic neighbor embedding (t-SNE) analyses identified diagnostically relevant spectral regions and visualized clustering between tumor classes. Collectively, this work establishes biomineralization as a strategy for transforming complex biomolecular and cellular information into computationally resolvable optical fingerprints, enabling scalable and label-free diagnostic classification of patient-derived biomolecular samples.
Picot, A.; Leboucher, M.; Helaine, C.; Talukdar, A.; Khalin, I.; Martinez de Lizarrondo, S.; Gauberti, M.; Nomenjanahary, M.; Goux, D.; Ho-Tin-Noe, B.; Vivien, D.; Bonnard, T.
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Clot resistance to pharmacological thrombolysis remains a critical challenge in ischemic stroke (IS) management. Thrombus heterogeneity, particularly the presence of thrombolysis-resistant domains composed of dense fibrin and non-fibrin components, including neutrophil extracellular traps (NETs), significantly limits the efficacy of recombinant tissue-type plasminogen activator (r-tPA) and its variant, Tenecteplase (TNK). Consequently, novel therapeutic strategies are urgently required. Emerging evidence suggests that co-administration of deoxyribonuclease I (DNase I) with r-tPA can degrade DNA fibers and enhance clot lysis. In this study, we optimized a previously developed theranostic agent--iron oxide microparticles coated with polydopamine--by dual-grafting both r-tPA and DNase to target resistant thrombi. Using functional ultrasound imaging (fUS) during the acute phase of IS, we demonstrated accelerated reperfusion with this dual-functionalized platform in a r-tPA resistant IS model. Furthermore, MRI analysis confirmed a significant reduction in lesion volume at 24 hours, correlating with improved functional recovery five days post-ischemia.
Roh, S.; Han, S.; Bae, M.; Song, E.; Lee, T.; Kang, D.; Cheong, D. Y.; Lee, H.; Kim, S.; Lee, G.
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Amyloid fibrils are implicated in a wide spectrum of neurodegenerative and systemic disorders, yet their biological consequences are governed not only by total fibril content but also by how fibrillar species are organized, clustered, and amplified within heterogeneous populations. Conventional thioflavin T (ThT)-based assays provide sensitive sample-level readouts of {beta}-sheet-rich material but offer limited access to the local population structure underlying amyloid aggregation and amplification. Here, we introduce the Amyloid Pore Quantification (APQ) chip, a pore-resolved geometric partitioning platform that converts heterogeneous amyloid assembly states into fluorescence intensity distributions across thousands of defined pore-level units. Using hen egg-white lysozyme as a model amyloid-forming protein, we combine length-controlled truncated amyloid nanofibrils with vacuum-assisted ThT infiltration to establish a reproducible pore fluorescence intensity reference. APQ provided quantitative concentration-dependent calibration across a 50-fold concentration range, enabling bulk-comparable quantification while preserving pore-level distribution information. Deviations from this reference resolved pH-dependent fibril clustering near the isoelectric point as pore-signal suppression and accessibility loss, captured pepsin-associated fibrillar amplification as a population-wide increase in pore intensity, and distinguished monomer- and oligomer-driven fibril processing through coupled amplification-aggregation fingerprints. When benchmarked against ensemble fluorescence measurements and AFM morphological analysis, APQ revealed assembly-state changes that were not fully represented by sample-level ThT intensity alone. These results establish APQ as a high-throughput, distribution-aware analytical framework for translating amyloid aggregation and amplification into quantitative pore-resolved fingerprints.
Wienbeuker, E.; Felker, A.; Nevskyi, O.; Harms, S. T.; Marx, D.; Tanzusch, K.; Chizhik, A.; Kurre, R.; You, C.; Enderlein, J.; Piehler, J.
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Transmembrane signaling mediated by cytokine receptors orchestrates key cellular processes such as proliferation, differentiation, and immune responses. While numerous high-resolution structures of cytokine receptor ectodomains are available, the structural organization of the largely disordered intracellular domain (ICD) has remained unclear. Here, we interrogate the axial organization of cytokine receptor signaling complexes at the plasma membrane by metal-induced energy transfer (MIET). For this purpose, we leveraged biofunctionalized nanodot arrays (bNDAs) to capture cell surface receptors at a defined distance from the substrate. Readout by fluorescence lifetime imaging microscopy enabled quantifying axial distances of proteins in the plasma membrane of cells at both ensemble and single-molecule levels with a resolution of [~]1 nm. Using the prototypic, biomedically relevant class I cytokine receptor GP130 as a model system, we uncover by MIET that the ICD extends randomly into the cytosol in the resting state, but surprisingly undergoes an axial compaction upon signal activation. These results demonstrate the potential of bNDA-supported MIET for resolving the axial architecture of signaling complexes within the cellular context.
Pang, C.; Wang, J.; Montaser, A.; Ma, S.; Leinonen, H.; Hu, G.; Lehto, V.-P.; Fan, L.; Xu, W.
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Virus-like particles represent an emerging and promising vaccine platform. However, these particles are inherently mechanically soft and have limited control over particle surface architecture, thereby constraining their immunological control. Herein, we report the rational design of bioinspired virus-like porous silica (VLPSi) nanoparticles (NPs) with tunable and mechanically rigid spike architectures that function dually as antigen delivery carriers and immune adjuvants. Using ovalbumin (OVA) as a model antigen, we systematically elucidate the spiky structure-function relationship in antigen delivery and immune response. VLPSi NPs exhibit good biocompatibility, sustained antigen release, and markedly enhanced cellular uptake and endosomal escape compared with soft spike and spherical counterparts. Mechanistic investigations combining molecular dynamics simulations and proteomic analyses reveal that rigid spike architectures reduce the energetic barrier for cellular internalization and concurrently activate dual pathways involving endosomal Toll like receptors and calcium signaling. Consequently, VLPSi with long spikes elicit significantly enhanced humoral and cellular immune responses, outperforming the particles with shorter spikes, spherical shape as well as clinically used alum adjuvant. To demonstrate translational potential, bioinspired antibacterial vaccines were produced by loading Staphylococcus aureus surface protein rEsxB. The VLPSi-based vaccine elicited robust protective immunity to achieve complete (100%) survival following lethal challenge without detectable adverse effects, whereas traditional Alum-adjuvanted formulation conferred only minimal protection, with a survival rate of 10%. Collectively, this work establishes VLPSi with tunable spikes as a mechanistically controlled platform for next generation vaccines. Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=145 SRC="FIGDIR/small/720861v1_ufig1.gif" ALT="Figure 1"> View larger version (47K): org.highwire.dtl.DTLVardef@1f6c13eorg.highwire.dtl.DTLVardef@1090d07org.highwire.dtl.DTLVardef@1364926org.highwire.dtl.DTLVardef@fc68ab_HPS_FORMAT_FIGEXP M_FIG C_FIG
Yen, M. H.; Kesama, M. R.; Du, Y.; Choi, J. H.; Solomon, K. V.
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Bottom-up manufacturing of structural DNA nanotechnology requires a long single-stranded DNA (ssDNA) scaffold and hundreds of short ([~]30 nt) ssDNA staples. However, scaling production remains bottlenecked by the high economic cost and environmental footprint of solid-phase chemical staple synthesis. To address these limitations, a phage-free, biological nanomanufacturing platform engineered in Escherichia coli is developed here. Two intracellular strategies for producing programmable ssDNA were systematically evaluated: retron-based multicopy ssDNA (msDNA) synthesis via the Ec67 system and plasmid-encoded rolling circle replication (RCR). While native structural topology constraints within the retron (msd) cassette limit its sequence-design flexibility, the alternative RCR-driven engine successfully decouples ssDNA replication from sequence secondary structures, enabling the synthesis of arbitrary staples. This RCR platform reliably generates long circular ssDNA (cssDNA) precursors of at least 1.8 kb with exceptional sequence fidelity (>99%). Integrating programmable BseGI cleavage sites allows targeted strand-selective enzymatic processing to cleanly release stoichiometric, origami-grade pools of 32-nt staple strands. Atomic force microscopy (AFM) confirms that these biologically produced staples successfully drive the high-fidelity self-assembly of complex DNA tiles and hollow tubules. Crucially, robust structural folding is demonstrated directly within crude, unpurified cellular lysates, establishing a green, cost-effective framework for the one-pot fabrication of advanced DNA-based nanomaterials.
Hu, H.; Krah, D.; Ntolkeras, A.; Chanda, S.; Heimbrodt, A.; Mondal, M.; Altendorf, J.; Jing, B.; Berger, B.; Shaib, A. H.; Rizzoli, S.; Boyden, E. S.
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Biological macromolecules, such as proteins, are made of concatenated building blocks. We hypothesized that individual protein residues could be imaged by anchoring their side chains to a swellable polymer, cleaving backbone amide bonds, and expanding residues away from each other to a degree that enables them to be visualized separately. We introduce thousandfold expansion microscopy (1000ExM), a four-network interpenetrating hydrogel architecture that enables successive expansion from [~]18-fold to >1000-fold (one billion-fold in volume). Protein and peptide structures are maintained across these expansion factors, as verified by analyses of proteins with known structures (nanobodies, GFP) and a well-studied peptide (mCLING). Computational analysis indicates that 1000ExM resolves adjacent amino acid residues, thereby achieving sub-nanometer precision on conventional light microscopes. We anticipate that 1000ExM will find wide utility in protein visualization and identification, potentially even in intact cells and tissues.
Chaudhary, N.; Coleman, H. J.; Paolone, E. V.; Yu, J.; Ledbetter, A. W.; Lemnios, A. A.; Walsh, A. A.; Suh, H.; Wang, A.; Mansoor, M. M.; Giancola, J. B.; Melo, M. B.; Rauch, A. M.; Langsfeld, E. S.; Parlikar, U. R.; Pacheco, M. O.; Williams, C. A.; Funke, H. H.; Garcea, R. L.; Randolph, T. W.; Irvine, D. J.
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Technologies that simplify complex dosing regimens as single-shot immunizations may be important for vaccines against difficult to neutralize pathogens. Here we characterized delivery mechanism of clinically-relevant HIV vaccine immunogens using core-shell microparticles comprising immunogen formulations spray-dried to form solid spherical microparticles and subsequently coated with a nanoscopic alumina shell using atomic layer deposition (ALD). ALD particles exhibited a time delay in antigen release programmed by the alumina shell followed by prolonged antigen release, which steadily accumulated in antigen-presenting cells at the injection site and draining lymph nodes and accumulated on follicular dendritic cells in B cell follicles. ALD vaccines elicited continuous expansion of antigen-specific germinal center B cells over 8 weeks, serum antibody responses with >10-fold slower antigen-binding off-rates, and 2-fold more long-lived plasma cells compared to traditional bolus vaccination with potent adjuvants. Single administration ALD technology thus promotes key events in the primary immune response important for vaccines against HIV and other challenging pathogens.
Mochalova, E. N.; Yurchenko, M. A.; Timofeeva, M. P.; Maedi, D. A.; Nikitin, P. I.; Nikitin, M. P.
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While engineered nanomaterials offer unprecedented precision in targeting tumor cells, their efficacy is often limited by rapid clearance from the bloodstream via the mononuclear phagocyte system (MPS). To overcome this limitation, a promising strategy known as MPS-cytoblockade has been developed. This approach involves administering antibodies against host erythrocytes. The resulting saturation of the MPS with erythrocyte clearance creates a critical window, allowing subsequently administered nanoparticles to evade immune surveillance and circulate for a significantly extended period. However, MPS-cytoblockade induces a transient reduction in hematocrit, which can lead to adverse effects. Here, we demonstrate that approaches to restore hematocrit, specifically through the administration of donor erythrocyte suspension or the hormone erythropoietin, effectively prevent this drop while maintaining the efficacy of the MPS-cytoblockade. Notably, these interventions do not compromise the prolonged circulation time of the nanoparticles or alter their biodistribution, preserving high accumulation in tumors. Our findings establish a viable strategy to mitigate a key side effect of MPS-cytoblockade, thereby enhancing its therapeutic potential and safety profile.
Vasquez, I.; Nash, L.; Shahriar, M. T.; Megahed, M.; Cao-Xue, J.; De Leon, I.; Xu, C.; Bickel, U.; Raghavan, S. A.; Srivastava, I.
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Ovarian cancer remains the most lethal gynecological malignancy, primarily due to late-stage diagnosis and the challenges of achieving complete cytoreduction. While fluorescence image-guided surgery (FIGS) offers intraoperative visualization, current clinical agents are limited by insufficient brightness, rapid photobleaching, and poor molecular selectivity, particularly in the near-infrared window. Here, we report the rational modular design of ultrabright NIR-II semiconducting polymer (SP) nanofluorophores for high-fidelity ovarian cancer imaging. By nanoconfining of a representative hydrophobic SP within a functional albumin matrix induces a "chaperone" effect that suppresses aggregation-induced quenching and shifts emission in the NIR-II window (1000-1250 nm). This platform integrates a dual-receptor targeting strategy, leveraging intrinsic albumin-receptor interactions (GP60 and SPARC) alongside folate receptor alpha (FR) functionalization. This synergistic approach enables pan-ovarian cancer imaging by ensuring high-affinity binding across diverse tumor phenotypes, regardless of heterogeneous receptor expression. Across a multiscale validation framework, the nanofluorophores demonstrate efficient receptor-mediated endocytosis in 2D cultures and deep interstitial penetration in 3D tumor spheroids. Furthermore, microfluidic tumor-on-chip models incorporating endothelial-like fenestrations confirm controlled extravasation and targeting under physiological shear stress. 3D bioprinted tumor phantoms and ex vivo porcine ovary tissues further confirm that BSA-FA@SP2 provides superior lesion delineation and signal-to-background ratios compared to indocyanine green, a clinical standard. Importantly, the nanofluorophores exhibit excellent hemocompatibility, with minimal hemolysis and negligible complement activation, indicating a non-immunogenic, stealth profile. Collectively, this work establishes albumin-shielded NIR-II nanofluorophores as a robust platform for precision intraoperative pan-ovarian imaging and advances the translational potential of nanotechnology-enabled surgical oncology.