Integrated Methodology from Synthesis to Study that Identifies Nanostructure Shape "Hot Spots" in T Cell Receptor Repertoire.

A new integrated tunable microfluidic particle synthesis and shape population analysis workflow allows us to study the immunological readouts for even highly complex shaped nanoparticles. Using this approach, we demonstrate that some gold nanoparticles, when injected parenterally, are taken up by axillary and brachial lymph nodes. We then show that specific nanoparticle shapes influence the primary structure of the T cell receptor, inducing changes in hypervariable complementary-determining regions (CDRs) and increasing the clonal diversity of the T cell receptor repertoires.

Unraveling biomolecular and community grammars of RNA granules via machine learning.

Membraneless RNA granules are essential for posttranscriptional gene regulation, influencing cellular functions and contributing to neurodegenerative diseases. However, a comprehensive understanding of their compositions and organization has been challenging due to their complex nature. In this study, we develop robust machine learning models to reliably identify RNA granule proteomes within the human proteome, capturing central RNA granule characteristics despite the heterogeneity across diverse in vitro conditions.

Quartz Crystal Microbalance Method to Measure Nanoparticle-Receptor Interactions and Evaluate Nanoparticle Design Efficiency.

Conjugation of biomolecules on the surface of nanoparticles (NPs) to achieve active targeting is widely investigated within the scientific community. However, while a basic framework of the physicochemical processes underpinning bionanoparticle recognition is now emerging, the precise evaluation of the interactions between engineered NPs and biological targets remains underdeveloped. Here, we show how the adaptation of a method currently used to evaluate molecular ligand-receptor interactions by quartz crystal microbalance (QCM) can be used to obtain concrete insights into interactions between different NP architectures and assemblies of receptors.

Nanoscale shape-dependent histone modifications.

Recent observations suggest a role for complex nanoscale particulate shape in the regulation of specific immune-related cellular and in vivo processes. We suspect that cellular recognition of nanostructure architecture could involve nonmolecular inputs, including cellular transduction of nanoscale spatially resolved stresses induced by complex shape. Here, we report nanoscale shape-dependent control of the cellular epigenome.

The Yin and Yang of the protein corona on the delivery journey of nanoparticles.

Nanoparticles-based drug delivery systems have attracted significant attention in biomedical fields because they can deliver loaded cargoes to the target site in a controlled manner. However, tremendous challenges must still be overcome to reach the expected targeting and therapeutic efficacy . These challenges mainly arise because the interaction between nanoparticles and biological systems is complex and dynamic and is influenced by the physicochemical properties of the nanoparticles and the heterogeneity of biological systems.

Spatiotemporal Tracing of the Cellular Internalization Process of Rod-Shaped Nanostructures.

Endocytosis, as one of the main ways for nanostructures enter cells, is affected by several aspects, and shape is an especially critical aspect during the endocytosis of nanostructures. However, it has remained challenging to capture the dynamic internalization behaviors of rod-shaped nanostructures while also probing the mechanical aspects of the internalization. Here, using the atomic force microscopy-based force tracing technique, transmission electron microscopy, and molecular dynamic simulation, we mapped the detailed internalization behaviors of rod-shaped nanostructures with different aspect ratios at the single-particle level.

Designing Functional Bionanoconstructs for Effective Targeting.

The progress achieved over the last three decades in the field of bioconjugation has enabled the preparation of sophisticated nanomaterial-biomolecule conjugates, referred to herein as bionanoconstructs, for a multitude of applications including biosensing, diagnostics, and therapeutics. However, the development of bionanoconstructs for the active targeting of cells and cellular compartments, both and , is challenged by the lack of understanding of the mechanisms governing nanoscale recognition. In this review, we highlight fundamental obstacles in designing a successful bionanoconstruct, considering findings in the field of bionanointeractions.

A microfluidic approach for synthesis and kinetic profiling of branched gold nanostructures.

Automatized approaches for nanoparticle synthesis and characterization represent a great asset to their applicability in the biomedical field by improving reproducibility and standardization, which help to meet the selection criteria of regulatory authorities. The scaled-up production of nanoparticles with carefully defined characteristics, including intrinsic morphological features, and minimal intra-batch, batch-to-batch, and operator variability, is an urgent requirement to elevate nanotechnology towards more trustable biological and technological applications. In this work, microfluidic approaches were employed to achieve fast mixing and good reproducibility in synthesizing a variety of gold nanostructures.

A Nanoscale Shape-Discovery Framework Supporting Systematic Investigations of Shape-Dependent Biological Effects and Immunomodulation.

Since it is now possible to make, in a controlled fashion, an almost unlimited variety of nanostructure shapes, it is of increasing interest to understand the forms of biological control that nanoscale shape allows. However, rational investigation of such a vast universe of shapes appears to present intractable fundamental and practical challenges. This has limited the useful systematic investigation of their biological interactions and the development of innovative nanoscale shape-dependent therapies.

Nanophysical Mapping of Inflammasome Activation by Nanoparticles via Specific Cell Surface Recognition Events.

Silica nanoparticles (SiNP) trigger a range of innate immune responses in relevant essential organs, such as the liver and the lungs. Inflammatory reactions, including NLRP3 inflammasome activation, have been linked to particulate materials; however, the molecular mechanisms and key actors remain elusive. Although many receptors, including several scavenger receptors, were suggested to participate in SiNP cellular uptake, mechanistic evidence of their role on innate immunity is lacking.

Transportation of AIE-visualized nanoliposomes is dominated by the protein corona.

Liposomes, especially cationic liposomes, are the most common and well-investigated nanocarriers for biomedical applications, such as drug and gene delivery. Like other types of nanomaterials, once liposomes are incubated in a biological milieu, their surface can be immediately cloaked by biological components to form a protein corona, which confers a new 'biological identity' and modulates downstream interactions with cells. However, it remains unclear how the protein corona affects the transportation mechanism after liposomes interact with cells.

Multifunctional superparamagnetic nanoparticles with a fluorescent silica shell for the study of bio-nano interactions at the subcellular scale.

Despite the high level of interest in bio-nano interactions, detailed intracellular mechanisms that govern nanoscale recognition and signalling still need to be unravelled. Magnetic nanoparticles (NPs) are valuable tools for elucidating complex intracellular bio-nano interactions. Using magnetic NPs, it is possible to isolate cell compartments that the particles interact with during intracellular trafficking.

In depth characterisation of the biomolecular coronas of polymer coated inorganic nanoparticles with differential centrifugal sedimentation.

Advances in nanofabrication methods have enabled the tailoring of new strategies towards the controlled production of nanoparticles with attractive applications in healthcare. In many cases, their characterisation remains a big challenge, particularly for small-sized functional nanoparticles of 5 nm diameter or smaller, where current particle sizing techniques struggle to provide the required sensitivity and accuracy. There is a clear need for the development of new reliable characterisation approaches for the physico-chemical characterisation of nanoparticles with significant accuracy, particularly for the analysis of the particles in the presence of complex biological fluids.

Impact of dynamic sub-populations within grafted chains on the protein binding and colloidal stability of PEGylated nanoparticles.

Polyethylene glycol grafting has played a central role in preparing the surfaces of nano-probes for biological interaction, to extend blood circulation times and to modulate protein recognition and cellular uptake. However, the role of PEG graft dynamics and conformation in determining surface recognition processes is poorly understood primarily due to the absence of a microscopic picture of the surface presentation of the polymer. Here a detailed NMR analysis reveals three types of dynamic ethylene glycol units on PEG-grafted SiO2 nanoparticles (NPs) of the type commonly evaluated as long-circulating theranostic nano-probes; a narrow fraction with fast dynamics associated with the chain ends; a broadened fraction spectrally overlapped with the former arising from those parts of the chain experiencing some dynamic restriction; and a fraction too broad to be observed in the spectrum arising from units closer to the surface/graft which undergo slow motion on the NMR timescale.

Understanding intracellular nanoparticle trafficking fates through spatiotemporally resolved magnetic nanoparticle recovery.

The field of nanomedicine has the potential to be a game-changer in global health, with possible applications in prevention, diagnostics, and therapeutics. However, despite extensive research focus and funding, the forecasted explosion of novel nanomedicines is yet to materialize. We believe that clinical translation is ultimately hampered by a lack of understanding of how nanoparticles really interact with biological systems.

X-ray-Based Techniques to Study the Nano-Bio Interface.

X-ray-based analytics are routinely applied in many fields, including physics, chemistry, materials science, and engineering. The full potential of such techniques in the life sciences and medicine, however, has not yet been fully exploited. We highlight current and upcoming advances in this direction.

Current understanding of biological identity at the nanoscale and future prospects.

Nanoscale objects are processed by living organisms using highly evolved and sophisticated endogenous cellular networks, specifically designed to manage objects of this size. While these processes potentially allow nanostructures unique access to and control over key biological machineries, they are also highly protected by cell or host defence mechanisms at all levels. A thorough understanding of bionanoscale recognition events, including the molecules involved in the cell recognition machinery, the nature of information transferred during recognition processes and the coupled downstream cellular processing, would allow us to achieve a qualitatively novel form of biological control and advanced therapeutics.

Improving Quality in Nanoparticle-Induced Cytotoxicity Testing by a Tiered Inter-Laboratory Comparison Study.

The quality and relevance of nanosafety studies constitute major challenges to ensure their key role as a supporting tool in sustainable innovation, and subsequent competitive economic advantage. However, the number of apparently contradictory and inconclusive research results has increased in the past few years, indicating the need to introduce harmonized protocols and good practices in the nanosafety research community. Therefore, we aimed to evaluate if best-practice training and inter-laboratory comparison (ILC) of performance of the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay for the cytotoxicity assessment of nanomaterials among 15 European laboratories can improve quality in nanosafety testing.

Ultrasmall Gold Nanoparticle Cellular Uptake: Influence of Transient Bionano Interactions.

Ultrasmall nanoparticles are attracting an increasing interest for a variety of biomedical applications, from therapeutic targeting to imaging, in virtue of the peculiar behavior shown (i.e., efficient renal clearance, low liver accumulation, etc.

A head-to-head Caco-2 assay comparison of the mechanisms of action of the intestinal permeation enhancers: SNAC and sodium caprate (C).

Salcaprozate sodium (SNAC) and sodium caprate (C) are the two leading intestinal permeation enhancers (PEs) in oral peptide formulations in clinical trials. There is debate over their mechanism of action on intestinal epithelia. The aims were: (i) to compare their effects on the barrier function by measuring transepithelial electrical resistance (TEER), permeability of FITC-4000 (FD4) across Caco-2 monolayers, and on immunohistochemistry of tight junction (TJ)-associated proteins; and (ii) to compare cellular parameters using conventional end-point cytotoxicity assays and quantitative high content analysis (HCA) of multiple sub-lethal parameters in Caco-2 cells.

Ultrathin Silicon Membranes for Optical Analysis of Nanoparticle Translocation across a Human Blood-Brain Barrier Model.

Here we present a blood-brain barrier (BBB) model that enables high-resolution imaging of nanoparticle (NP) interactions with endothelial cells and the capture of rare NP translocation events. The enabling technology is an ultrathin silicon nitride (SiN) membrane (0.5 μm pore size, 20% porosity, 400 nm thickness) integrated into a dual-chamber platform that facilitates imaging at low working distances (∼50 μm).

A Three-Dimensional Cell Culture Platform for Long Time-Scale Observations of Bio-Nano Interactions.

We know surprisingly little about the long-term outcomes for nanomaterials interacting with organisms. To date, most of what we know is derived from studies that limit the range of materials studied and the scope of advanced molecular biology tools applied. Long-term nanoparticle studies are hampered by a lack of suitable models, as standard cell culture techniques present several drawbacks, while technical limitations render current three-dimensional (3D) cellular spheroid models less suited.

Magnetic One-Step Purification of His-Tagged Protein by Bare Iron Oxide Nanoparticles.

Magnetic separation is a promising alternative to conventional methods in downstream processing. This can facilitate easier handling, fewer processing steps, and more sustainable processes. Target materials can be extracted directly from crude cell lysates in a single step by magnetic nanoadsorbents with high-gradient magnetic fishing (HGMF).

A high-throughput microscopy method for single-cell analysis of event-time correlations in nanoparticle-induced cell death.

The temporal context of cell death decisions remains generally hidden in ensemble measurements with endpoint readouts. Here, we describe a method to extract event times from fluorescence time traces of cell death-related markers in automated live-cell imaging on single-cell arrays (LISCA) using epithelial A549 lung and Huh7 liver cancer cells as a model system. In pairwise marker combinations, we assess the chronological sequence and delay times of the events lysosomal membrane permeabilization, mitochondrial outer membrane permeabilization and oxidative burst after exposure to 58 nm amino-functionalized polystyrene nanoparticles (PS-NH nanoparticles).