The effects of protein corona on in vivo fate of nanocarriers

Photo-induced Oriented Crystallization of Intracellular Nanocrystals Based on Phase Separation for Diagnostic Bioimaging and Analysis

Biomineral crystals form complex nonequilibrium structures based on the multistep nucleation theory, via transient amorphous precursors. However, the intricate nature of the biological system results in the inconsistent frequency of nucleation and crystallization, which making it problematic to obtain homogeneous nanocrystals, limits their application in biomedicine. Here, it is reported that homogeneous nanocrystals of photoinduced oriented crystallization with protein coronas are based on intracellular liquid-liquid phase separation for in situ analysis and mapping of surface-enhanced Raman spectroscopy (SERS). Near-infrared light promotes the formation of intracellular dense phases, accelerates the nucleation of gold atoms at secondary structure sites of proteins, and promotes the growth of crystals. Homogeneous gold nanocrystals with stable SERS signals can be used to analysis different cell cycles and acquire in situ molecular information of metastatic tumor cells. Of note are tag molecule is embedded in protein coronas of gold nanocrystals to enable the mapping of patient tumor tissue samples and the portable recognition of tumor cells. Thus, this study proposes a new strategy for biomineralization of intracellular homogeneous gold nanocrystals and its potential application.

Interactions between nanoparticles and lymphatic systems: Mechanisms and applications in drug delivery

The lymphatic system has garnered significant attention in drug delivery research due to the advantages it offers, such as enhancing systemic exposure and enabling lymph node targeting for nanomedicines via the lymphatic delivery route. The journey of drug carriers involves transport from the administration site to the lymphatic vessels, traversing the lymph before entering the bloodstream or targeting specific lymph nodes. However, the anatomical and physiological barriers of the lymphatic system play a pivotal role in influencing the behavior and efficiency of carriers. To expedite research and subsequent clinical translation, this review begins by introducing the composition and classification of the lymphatic system. Subsequently, we explore the routes and mechanisms through which nanoparticles enter lymphatic vessels and lymph nodes. The review further delves into the interactions between nanomedicine and body fluids at the administration site or within lymphatic vessels. Finally, we provide a comprehensive overview of recent advancements in lymphatic delivery systems, addressing the challenges and opportunities inherent in current systems for delivering macromolecules and vaccines.

Cellular uptake and in vitro antibacterial activity of lipid-based nanoantibiotics are influenced by protein corona

Bacteria have evolved survival mechanisms that enable them to live within host cells, triggering persistent intracellular infections that present significant clinical challenges due to the inability for conventional antibiotics to permeate cell membranes. In recent years, antibiotic nanocarriers or 'nanoantibiotics' have presented a promising strategy for overcoming intracellular infections by facilitating cellular uptake of antibiotics, thus improving targeting to the bacteria. However, prior to reaching host cells, nanocarriers experience interactions with proteins that form a corona and alter their physiological response. The influence of this protein corona on the cellular uptake, drug release and efficacy of nanoantibiotics for intracellular infections is poorly understood and commonly overlooked in preclinical studies. In this study, protein corona influence on cellular uptake was investigated for two nanoparticles; liposomes and cubosomes in macrophage and epithelial cells that are commonly infected with pathogens. Studies were conducted in presence of fetal bovine serum (FBS) to form a biologically relevant protein corona in an in vitro setting. Protein corona impact on cellular uptake was shown to be nanoparticle-dependent, where reduced internalization was observed for liposomes, the opposite was observed for cubosomes. Subsequently, vancomycin-loaded cubosomes were explored for their drug delivery performance against intracellular small colony variants of Staphylococcus aureus. We demonstrated improved bacterial killing in macrophages, with greater reduction in bacterial viability upon internalization of cubosomes mediated by the protein corona. However, no differences in efficacy were observed in epithelial cells. Thus, this study provides insights and evidence to the role of protein corona in modulating the performance of nanoparticles in a dynamic manner; these findings will facilitate improved understanding and translation of future investigations from in vitro to in vivo.

Empowering lung cancer treatment: Harnessing the potential of natural phytoconstituent-loaded nanoparticles

Lung cancer, the second leading cause of cancer-related deaths, accounts for a substantial portion, representing 18.4% of all cancer fatalities. Despite advances in treatment modalities such as chemotherapy, surgery, and immunotherapy, significant challenges persist, including chemoresistance, non-specific targeting, and adverse effects. Consequently, there is an urgent need for innovative therapeutic approaches to overcome these limitations. Natural compounds, particularly phytoconstituents, have emerged as promising candidates due to their potent anticancer properties and relatively low incidence of adverse effects compared to conventional treatments. However, inherent challenges such as poor solubility, rapid metabolism, and enzymatic degradation hinder their clinical utility. To address these obstacles, researchers have increasingly turned to nanotechnology-based drug delivery systems (DDS). Nanocarriers offer several advantages, including enhanced drug stability, prolonged circulation time, and targeted delivery to tumor sites, thereby minimizing off-target effects. By encapsulating phytoconstituents within nanocarriers, researchers aim to optimize their bioavailability and therapeutic efficacy while reducing systemic toxicity. Moreover, the integration of nanotechnology with phytoconstituents allows for a nuanced understanding of the intricate molecular pathways involved in lung cancer pathogenesis. This integrated approach holds promise for modulating key cellular processes implicated in tumor growth and progression. Additionally, by leveraging the synergistic effects of phytoconstituents and nanocarriers, researchers seek to develop tailored therapeutic strategies that maximize efficacy while minimizing adverse effects. In conclusion, the integration of phytoconstituents with nanocarriers represents a promising avenue for advancing lung cancer treatment. This synergistic approach has the potential to revolutionize current therapeutic paradigms by offering targeted, efficient, and minimally toxic interventions. Continued research in this field holds the promise of improving patient outcomes and addressing unmet clinical needs in lung cancer management.

Nanoplastic Size and Surface Chemistry Dictate Decoration by Human Saliva Proteins

Environmental pollution with plastic polymers has become a global problem, leaving no continent and habitat unaffected. Plastic waste is broken down into smaller parts by environmental factors, which generate micro- and nanoplastic particles (MNPPs), ultimately ending up in the human food chain. Before entering the human body, MNPPs make their first contact with saliva in the human mouth. However, it is unknown what proteins attach to plastic particles and whether such protein corona formation is affected by the particle's biophysical properties. To this end, we employed polystyrene MNPPs of two different sizes and three different charges and incubated them individually with saliva donated by healthy human volunteers. Particle zeta potential and size analyses were performed using dynamic light scattering complemented by nanoliquid chromatography high-resolution mass spectrometry (nLC/HRMS) to qualitatively and quantitatively reveal the protein soft and hard corona for each particle type. Notably, protein profiles and relative quantities were dictated by plastic particle size and charge, which in turn affected their hydrodynamic size, polydispersity, and zeta potential. Strikingly, we provide evidence of the latter to be dynamic processes depending on exposure times. Smaller particles seemed to be more reactive with the surrounding proteins, and cultures of the particles with five different cell lines (HeLa, HEK293, A549, HepG2, and HaCaT) indicated protein corona effects on cellular metabolic activity and genotoxicity. In summary, our data suggest nanoplastic size and surface chemistry dictate the decoration by human saliva proteins, with important implications for MNPP uptake in humans.

An antifouling membrane-fusogenic liposome for effective intracellular delivery in vivo

The membrane-fusion-based internalization without lysosomal entrapment is advantageous for intracellular delivery over endocytosis. However, protein corona formed on the membrane-fusogenic liposome surface converts its membrane-fusion performance to lysosome-dependent endocytosis, causing poorer delivery efficiency in biological conditions. Herein, we develop an antifouling membrane-fusogenic liposome for effective intracellular delivery in vivo. Leveraging specific lipid composition at an optimized ratio, such antifouling membrane-fusogenic liposome facilitates fusion capacity even in protein-rich conditions, attributed to the copious zwitterionic phosphorylcholine groups for protein-adsorption resistance. Consequently, the antifouling membrane-fusogenic liposome demonstrates robust membrane-fusion-mediated delivery in the medium with up to 38% fetal bovine serum, outclassing two traditional membrane-fusogenic liposomes effective at 4% and 6% concentrations. When injected into mice, antifouling membrane-fusogenic liposomes can keep their membrane-fusion-transportation behaviors, thereby achieving efficient luciferase transfection and enhancing gene-editing-mediated viral inhibition. This study provides a promising tool for effective intracellular delivery under complex physiological environments, enlightening future nanomedicine design.

Design of a targeted dual drug delivery system for boosting the efficacy of photoimmunotherapy against melanoma proliferation and metastasis

INTRODUCTION

The combination of a photosensitizer and indoleamine-2,3 dioxygenase (IDO) inhibitor provides a promising photoimmunotherapy (PIT) strategy for melanoma treatment. A dual drug delivery system offers a potential approach for optimizing the inhibitory effects of PIT on melanoma proliferation and metastasis.

OBJECTIVE

To develop a dual drug delivery system based on PIT and to study its efficacy in inhibiting melanoma proliferation and metastasis.

METHODS

We constructed a multifunctional nano-porphyrin material (P18-APBA-HA) using the photosensitizer-purpurin 18 (P18), hyaluronic acid (HA), and 4-(aminomethyl) phenylboronic acid (APBA). The resulting P18-APBA-HA was inserted into a phospholipid membrane and the IDO inhibitor epacadostat (EPA) was loaded into the internal phase to prepare a dual drug delivery system (Lip\EPA\P18-APBA-HA). Moreover, we also investigated its physicochemical properties, targeting, anti-tumor immunity, and anti-tumor proliferation and metastasis effects.

RESULTS

The designed system utilized the pH sensitivity of borate ester to realize an enhanced-targeting strategy to facilitate the drug distribution in tumor lesions and efficient receptor-mediated cellular endocytosis. The intracellular release of EPA from Lip\EPA\P18-APBA-HA was triggered by thermal radiation, thereby inhibiting IDO activity in the tumor microenvironment, and promoting activation of the immune response. Intravenous administration of Lip\EPA\P18-APBA-HA effectively induced anti-tumor immunity by promoting dendritic cell maturation, cytotoxic T cell activation, and regulatory T cell suppression, and regulating cytokine secretion, to inhibit the proliferation of melanoma and lung metastasis.

CONCLUSION

The proposed nano-drug delivery system holds promise as offers a promising strategy to enhance the inhibitory effects of the combination of EPA and P18 on melanoma proliferation and metastasis.

Phospholipid Type Regulates Protein Corona Composition and In Vivo Performance of Lipid Nanodiscs

Over the years, there has been significant interest in PEGylated lipid-based nanocarriers within the drug delivery field. The inevitable interplay between the nanocarriers and plasma protein plays a pivotal role in their in vivo biological fate. Understanding the factors influencing lipid-based nanocarrier and protein corona interactions is of paramount importance in the design and clinical translation of these nanocarriers. Herein, discoid-shaped lipid nanodiscs (sNDs) composed of different phospholipids with varied lipid tails and head groups were fabricated. We investigated the impact of phospholipid components on the interaction between sNDs and serum proteins, particle stability, and biodistribution. The results showed that all of these lipid nanodiscs remained stable over a 15 day storage period, while their stability in the blood serum demonstrated significant differences. The sND composed of POPG exhibited the least stability due to its potent complement activation capability, resulting in rapid blood clearance. Furthermore, a negative correlation between the complement activation capability and serum stability was identified. Pharmacokinetic and biodistribution experiments indicated that phospholipid composition did not influence the capability of sNDs to evade the accelerated blood clearance phenomenon. Complement deposition on the sND was inversely associated with the area under the curve. Additionally, all lipid nanodiscs exhibited dominant adsorption of apolipoprotein. Remarkably, the POPC-based lipid nanodisc displayed a significantly higher deposition of apolipoprotein E, contributing to an obvious brain distribution, which provides a promising tool for brain-targeted drug delivery.

Expanding Mn2+ loading capacity of BSA via mild non-thermal denaturing and cross-linking as a tool to maximize the relaxivity of water protons

Development of nanoparticles (NPs) serving as contrast enhancing agents in MRI requires a combination of high contrasting effect with the biosafety and hemocompatibility. This work demonstrates that bovine serum albumin (BSA) molecules bound to paramagnetic Mn2+ ions are promising building blocks of such NPs. The desolvation-induced denaturation of BSA bound with Mn2+ ions followed by the glutaraldehyde-facilitated cross-linking provides the uniform in size 102.0 ± 0.7 nm BSA-based nanoparticles (BSA-NPs) loaded with Mn2+ ions, which are manifested in aqueous solutions as negatively charged spheres with high colloid stability. The optimal loading of Mn2+ ions into BSA-NPs provides maximum values of longitudinal and transverse relaxivity at 98.9 and 133.6 mM-1 s-1, respectively, which are among the best known from the literature. The spin trap EPR method indicates that Mn2+ ions bound to BSA-NPs exhibit poor catalytic activity in the Fenton-like reaction. On the contrary, the presence of BSA-NPs has an antioxidant effect by preventing the accumulation of hydroxyl radicals produced by H2O2. The NPs exhibit remarkably low hemolytic activity and hemagglutination can be avoided at concentrations lower than 110 μM. Thus, BSA-NPs bound with Mn2+ ions are promising candidates for combining high contrast effect with biosafety and hemocompatibility.

Nanosystem Delivers Senescence Activators and Immunomodulators to Combat Liver Cancer

CD47 blockade has emerged as a promising immunotherapy against liver cancer. However, the optimization of its antitumor effectiveness using efficient drug delivery systems or combinations of therapeutic agents remains largely incomplete. Here, patients with liver cancer co-expressing CD47 and CDC7 (cell division cycle 7, a negative senescence-related gene) are found to have the worst prognosis. Moreover, CD47 is highly expressed, and senescence is inhibited after the development of chemoresistance, suggesting that combination therapy targeting CD47 and CDC7 to inhibit CD47 and induce senescence may be a promising strategy for liver cancer. The efficacy of intravenously administered CDC7 and CD47 inhibitors is limited by low uptake and short circulation times. Here, inhibitors are coloaded into a dual-targeted nanosystem. The sequential release of the inhibitors from the nanosystem under acidic conditions first induces cellular senescence and then promotes immune responses. In an in situ liver cancer mouse model and a chemotherapy-resistant mouse model, the nanosystem effectively inhibited tumor growth by 90.33% and 85.15%, respectively. Overall, the nanosystem in this work achieved the sequential release of CDC7 and CD47 inhibitors in situ to trigger senescence and induce immunotherapy, effectively combating liver cancer and overcoming chemoresistance.

Pre-coating cRGD-modified bovine serum albumin enhanced the anti-tumor angiogenesis of siVEGF-loaded chitosan-based nanoparticles by manipulating the protein corona composition

Chitosan-based nanoparticles inevitably adsorb numerous proteins in the bloodstream, forming a protein corona that significantly influences their functionality. This study employed a pre-coated protein corona using cyclic Arg-Gly-Asp peptide (cRGD)-modified bovine serum albumin (BcR) to confer tumor-targeting capabilities on siVEGF-loaded chitosan-based nanoparticles (CsR/siVEGF NPs) and actively manipulated the serum protein corona composition to enhance their anti-tumor angiogenesis. Consequently, BcR effectively binds to the nanoparticles' surface, generating nanocarriers of appropriate size and stability that enhance the inhibition of endothelial cell proliferation, migration, invasion, and tube formation, as well as suppress tumor proliferation and angiogenesis in tumor-bearing nude mice. Proteomic analysis indicated a significant enrichment of serotransferrin, albumin, and proteasome subunit alpha type-1 in the protein corona of BcR-precoated NPs formed in the serum of tumor-bearing nude mice. Additionally, there was a decrease in proteins associated with complement activation, immunoglobulins, blood coagulation, and acute-phase responses. This modification resulted in an enhanced impact on anti-tumor angiogenesis, along with a reduction in opsonization and inflammatory responses. Therefore, pre-coating of nanoparticles with a functionalized albumin corona to manipulate the composition of serum protein corona emerges as an innovative approach to improve the delivery effectiveness of chitosan-based carriers for siVEGF, targeting the inhibition of tumor angiogenesis.

Perspectives on Protein-Nanoparticle Interactions at the In Vivo Level

The distinct features of nanoparticles have provided a vast opportunity of developing new diagnosis and therapy strategies for miscellaneous diseases. Although a few nanomedicines are available in the market or in the translation stage, many important issues are still unsolved. When entering the body, nanomaterials will be quickly coated by proteins from their surroundings, forming a corona on their surface, the so-called protein corona. Studies have shown that the protein corona has many important biological implications, particularly at the in vivo level. For example, they can promote the immune system to rapidly clear these outer materials and prevent nanoparticles from playing their designed role in therapy. In this Perspective, the available techniques for characterizing protein-nanoparticle interactions are critically summarized. Effects of nanoparticle properties and environmental factors on protein corona formation, which can further regulate the in vivo fate of nanoparticles, are highlighted and discussed. Moreover, recent progress on the biomedical application of protein corona-engineered nanoparticles is introduced, and future directions for this important yet challenging research area are also briefly discussed.

Targeted delivery of MerTK protein via cell membrane engineered nanoparticle enhances efferocytosis and attenuates atherosclerosis in diabetic ApoE-/- Mice

BACKGROUND

Clearance of apoptotic cells by efferocytosis is crucial for prevention of atherosclerosis progress, and impaired efferocytosis contributes to the aggravated atherosclerosis.

RESULTS

In this study, we found that diabetic ApoE-/- mice showed aggravated atherosclerosis as hyperglycemia damaged the efferocytosis capacity at least partially due to decreased expression of Mer tyrosine kinase (MerTK) on macrophages. To locally restore MerTK in the macrophages in the plaque, hybrid membrane nanovesicles (HMNVs) were thus developed. Briefly, cell membrane from MerTK overexpressing RAW264.7 cell and transferrin receptor (TfR) overexpressing HEK293T cell were mixed with DOPE polymers to produce nanovesicles designated as HMNVs. HMNVs could fuse with the recipient cell membrane and thus increased MerTK in diabetic macrophages, which in turn restored the efferocytosis capacity. Upon intravenous administration into diabetic ApoE-/- mice, superparamagnetic iron oxide nanoparticles (SMN) decorated HMNVs accumulated at the aorta site significantly under magnetic navigation, where the recipient macrophages cleared the apoptotic cells efficiently and thus decreased the inflammation.

CONCLUSIONS

 Our study indicates that MerTK decrease in macrophages contributes to the aggravated atherosclerosis in diabetic ApoE-/- mice and regional restoration of MerTK in macrophages of the plaque via HMNVs could be a promising therapeutic approach.

Unveiling the challenges of engineered protein corona from the proteins' perspective

It is well known that protein corona affects the "biological identity" of nanoparticles (NPs), which has been seen as both a challenge and an opportunity. Approaches have moved from avoiding protein adsorption to trying to direct it, taking advantage of the formation of a protein corona to favorably modify the pharmacokinetic parameters of NPs. Although promising, the results obtained with engineered NPs still need to be completely understood. While much effort has been put into understanding how the surface of nanomaterials affects protein absorption, less is known about how proteins can affect corona formation due to their specific physicochemical properties. This review addresses this knowledge gap, examining key protein factors influencing corona formation, highlighting current challenges in studying protein-protein interactions, and discussing future perspectives in the field.

The In Vivo Biological Fate of Protein Corona: A Comparative PET Study of the Fate of Soft and Hard Protein Corona in Healthy Animal Models

Radiolabeling and nuclear imaging techniques are used to investigate the biodistribution patterns of the soft and hard protein corona around poly (lactic-co-glycolic acid) nanoparticles (PLGA NPs) after administration to healthy mice. Soft and hard protein coronas of 131I-labeled BSA or 131I-labeled serum are formed on PLGA NPs functionalized with either polyehtylenimine (PEI) or bovine serum albumin (BSA). The exchangeability of hard and soft corona is assessed in vitro by gamma counting exposing PLGA NPs with corona to non-labeled BSA, serum, or simulated body fluid. PEI PLGA NPs form larger and more stable coronas than BSA PLGA NPs. Soft coronas are more exchangeable than hard ones. The in vivo fate of PEI PLGA NPs coated with preformed 18F-labeled BSA hard and soft coronas is assessed by positron emission tomography (PET) following intravenous administration. While the soft corona shows a biodistribution similar to free 18F BSA with high activity in blood and kidney, the hard corona follows patterns characteristic of nanoparticles, accumulating in the lungs, liver, and spleen. These results show that in vivo fates of soft and hard corona are different, and that soft corona is more easily exchanged with proteins from the body, while hard corona is largely retained on the nanoparticle surface.

The interaction between particles and vascular endothelium in blood flow

Particle-based drug delivery systems have shown promising application potential to treat human diseases; however, an incomplete understanding of their interactions with vascular endothelium in blood flow prevents their inclusion into mainstream clinical applications. The flow performance of nano/micro-sized particles in the blood are disturbed by many external/internal factors, including blood constituents, particle properties, and endothelium bioactivities, affecting the fate of particles in vivo and therapeutic effects for diseases. This review highlights how the blood constituents, hemodynamic environment and particle properties influence the interactions and particle activities in vivo. Moreover, we briefly summarized the structure and functions of endothelium and simulated devices for studying particle performance under blood flow conditions. Finally, based on particle-endothelium interactions, we propose future opportunities for novel therapeutic strategies and provide solutions to challenges in particle delivery systems for accelerating their clinical translation. This review helps provoke an increasing in-depth understanding of particle-endothelium interactions and inspires more strategies that may benefit the development of particle medicine.

Enzyme-Mediated Bioorthogonal Cascade Catalytic Reaction for Metabolism Intervention and Enhanced Ferroptosis on Neuroblastoma

It remains a tremendous challenge to explore effective therapeutic modalities against neuroblastoma, a lethal cancer of the sympathetic nervous system with poor prognosis and disappointing treatment outcomes. Considering the limitations of conventional treatment modalities and the intrinsic vulnerability of neuroblastoma, we herein develop a pioneering sequential catalytic therapeutic system that utilizes lactate oxidase (LOx)/horseradish peroxidase (HRP)-loaded amorphous zinc metal-organic framework, named LOx/HRP-aZIF, in combination with a 3-indole-acetic acid (IAA) prodrug. On the basis of abnormal lactate accumulation that occurs in the tumor microenvironment, the cascade reaction of LOx and HRP consumes endogenous glutathione and a reduced form of nicotinamide adenine dinucleotide to achieve the first stage of killing cancer cells via antioxidative incapacitation and electron transport chain interference. Furthermore, the generation of reactive oxygen species induced by HRP and IAA through bioorthogonal catalysis promotes ferritin degradation and lipid peroxidation, ultimately provoking self-enhanced ferroptosis with positive feedback by initiating an endogenous Fenton reaction. This work highlights the superiority of the natural enzyme-dependent cascade and bioorthogonal catalytic reaction, offering a paradigm for synergistically enzyme-based metabolism-ferroptosis anticancer therapy.

Incorporation of poly(γ-glutamic acid) in lipid nanoparticles for enhanced mRNA delivery efficiency in vitro and in vivo

Messenger RNA (mRNA)-based therapy shows immense potential for broad biomedical applications. However, the development of safe and efficacious mRNA delivery vectors remains challenging due to delivery barriers and inefficient intracellular payload release. Herein, we presented a simple strategy to boost the mRNA intracellular release by incorporation of anionic poly(γ-glutamic acid) (PGA) into an ionizable lipid-based LNP/mRNA. We systematically investigated the impact of PGA incorporation on mRNA transfection both in vitro and in vivo. The molecular weights and formulation ratios of PGA greatly affected the transfection efficacy of LNP/mRNA. From in vitro study, the optimized LNP/mRNA/PGA was formulated by incorporation of PGA with the molecular weight of 80 kDa or 200 kDa and the charge ratio (N/P/C) of 25/1/1. The optimized formulation achieved around 3-fold mRNA expression in HeLa cells compared to the bare LNP/mRNA. The intracellular releasing study using specific DNA probe revealed that this enhancement of transfection efficacy was attributed to the elevated mRNA release into cytoplasm. Moreover, the optimized LNP/mRNA/PGA achieved up to 5-fold or 3-fold increase of luciferase mRNA expression in vivo after being injected into mice systematically or intramuscularly, respectively. In addition, the incorporation of PGA did not significantly alter the biodistribution profile of the complexes on both organ and cellular levels. Therefore, our work provides a simple strategy to boost mRNA delivery, which holds great promise to improve the efficacy of mRNA therapeutics for various biomedical applications. STATEMENT OF SIGNIFICANCE: The process of designing and screening potent mRNA carriers is complicated and time-consuming, while the efficacy is not always satisfying due to the delivery barriers and inefficient mRNA release. This work presented an alternative strategy to boost the mRNA delivery efficacy by incorporating an anionic natural polymer poly(γ-glutamic acid) (PGA) into LNP/mRNA complexes. The optimized LNP/mRNA/PGA achieved up to 3-fold and 5-fold increase in transfection efficacy in vitro and in vivo, respectively. Intracellular releasing analysis revealed that the enhancement of transfection efficacy was mainly attributed to the elevated intracellular release of mRNA. In addition, the incorporation of PGA did not alter the biodistribution or the biosafety profile of the complexes. These findings indicate that PGA incorporation is a promising strategy to improve the efficacy of mRNA therapeutics.

Protein Coronas Derived from Mucus Act as Both Spear and Shield to Regulate Transferrin Functionalized Nanoparticle Transcellular Transport in Enterocytes

The epithelial mucosa is a key biological barrier faced by gastrointestinal, intraoral, intranasal, ocular, and vaginal drug delivery. Ligand-modified nanoparticles demonstrate excellent ability on this process, but their efficacy is diminished by the formation of protein coronas (PCs) when they interact with biological matrices. PCs are broadly implicated in affecting the fate of NPs in vivo and in vitro, yet few studies have investigated PCs formed during interactions of NPs with the epithelial mucosa, especially mucus. In this study, we constructed transferrin modified NPs (Tf-NPs) as a model and explored the mechanisms and effects that epithelial mucosa had on PCs formation and the subsequent impact on the transcellular transport of Tf-NPs. In mucus-secreting cells, Tf-NPs adsorbed more proteins from the mucus layers, which masked, displaced, and dampened the active targeting effects of Tf-NPs, thereby weakening endocytosis and transcellular transport efficiencies. In mucus-free cells, Tf-NPs adsorbed more proteins during intracellular trafficking, which enhanced transcytosis related functions. Inspired by soft coronas and artificial biomimetic membranes, we used mucin as an "active PC" to precoat Tf-NPs (M@Tf-NPs), which limited the negative impacts of "passive PCs" formed during interface with the epithelial mucosa and improved favorable routes of endocytosis. M@Tf-NPs adsorbed more proteins associated with endoplasmic reticulum-Golgi functions, prompting enhanced intracellular transport and exocytosis. In summary, mucus shielded against the absorption of Tf-NPs, but also could be employed as a spear to break through the epithelial mucosa barrier. These findings offer a theoretical foundation and design platform to enhance the efficiency of oral-administered nanomedicines.

Exposure to high dose of polystyrene nanoplastics causes trophoblast cell apoptosis and induces miscarriage

BACKGROUND

With rapid increase in the global use of various plastics, microplastics (MPs) and nanoplastics (NPs) pollution and their adverse health effects have attracted global attention. MPs have been detected out in human body and both MPs and NPs showed female reproductive toxicological effects in animal models. Miscarriage (abnormal early embryo loss), accounting for 15-25% pregnant women worldwide, greatly harms human reproduction. However, the adverse effects of NPs on miscarriage have never been explored.

RESULTS

In this study, we identified that polystyrene (PS) plastics particles were present in women villous tissues. Their levels were higher in villous tissues of unexplained recurrent miscarriage (RM) patients vs. healthy control (HC) group. Furthermore, mouse assays further confirmed that exposure to polystyrene nanoplastics (PS-NPs, 50 nm in diameter, 50 or 100 mg/kg) indeed induced miscarriage. In mechanism, PS-NPs exposure (50, 100, 150, or 200 µg/mL) increased oxidative stress, decreased mitochondrial membrane potential, and increased apoptosis in human trophoblast cells by activating Bcl-2/Cleaved-caspase-2/Cleaved-caspase-3 signaling through mitochondrial pathway. The alteration in this signaling was consistent in placental tissues of PS-NPs-exposed mouse model and in villous tissues of unexplained RM patients. Supplement with Bcl-2 could efficiently suppress apoptosis in PS-NPs-exposed trophoblast cells and reduce apoptosis and alleviate miscarriage in PS-NPs-exposed pregnant mouse model.

CONCLUSIONS

Exposure to PS-NPs activated Bcl-2/Cleaved-caspase-2/Cleaved-caspase-3, leading to excessive apoptosis in human trophoblast cells and in mice placental tissues, further inducing miscarriage.

Modulating the toxicity of engineered nanoparticles by controlling protein corona formation: Recent advances and future prospects

With the rapid development and widespread application of engineered nanoparticles (ENPs), understanding the fundamental interactions between ENPs and biological systems is essential to assess and predict the fate of ENPs in vivo. When ENPs are exposed to complex physiological environments, biomolecules quickly and inevitably adsorb to ENPs to form a biomolecule corona, such as a protein corona (PC). The formed PC has a significant effect on the physicochemical properties of ENPs and gives them a brand new identity in the biological environment, which determines the subsequent ENP-cell/tissue/organ interactions. Controlling the formation of PCs is therefore of utmost importance to accurately predict and optimize the behavior of ENPs within living organisms, as well as ensure the safety of their applications. In this review, we provide an overview of the fundamental aspects of the PC, including the formation mechanism, composition, and frequently used characterization techniques. We comprehensively discuss the potential impact of the PC on ENP toxicity, including cytotoxicity, immune response, and so on. Additionally, we summarize recent advancements in manipulating PC formation on ENPs to achieve the desired biological outcomes. We further discuss the challenges and prospects, aiming to provide valuable insights for a better understanding and prediction of ENP behaviors in vivo, as well as the development of low-toxicity ENPs.

Strategies to Promote the Journey of Nanoparticles Against Biofilm-Associated Infections

Biofilm-associated infections are one of the most challenging healthcare threats for humans, accounting for 80% of bacterial infections, leading to persistent and chronic infections. The conventional antibiotics still face their dilemma of poor therapeutic effects due to the high tolerance and resistance led by bacterial biofilm barriers. Nanotechnology-based antimicrobials, nanoparticles (NPs), are paid attention extensively and considered as promising alternative. This review focuses on the whole journey of NPs against biofilm-associated infections, and to clarify it clearly, the journey is divided into four processes in sequence as 1) Targeting biofilms, 2) Penetrating biofilm barrier, 3) Attaching to bacterial cells, and 4) Translocating through bacterial cell envelope. Through outlining the compositions and properties of biofilms and bacteria cells, recent advances and present the strategies of each process are comprehensively discussed to combat biofilm-associated infections, as well as the combined strategies against these infections with drug resistance, aiming to guide the rational design and facilitate wide application of NPs in biofilm-associated infections.

Cellular uptake and in vivo distribution of mesenchymal-stem-cell-derived extracellular vesicles are protein corona dependent

Extracellular vesicles (EVs) derived from mesenchymal stem cells are promising nanotherapeutics in liver diseases due to their regenerative and immunomodulatory properties. Nevertheless, a concern has been raised regarding the rapid clearance of exogenous EVs by phagocytic cells. Here we explore the impact of protein corona on EVs derived from two culturing conditions in which specific proteins acquired from media were simultaneously adsorbed on the EV surface. Additionally, by incubating EVs with serum, simulating protein corona formation upon systemic delivery, further resolved protein corona-EV complex patterns were investigated. Our findings reveal the potential influences of corona composition on EVs under in vitro conditions and their in vivo kinetics. Our data suggest that bound albumin creates an EV signature that can retarget EVs from hepatic macrophages. This results in markedly improved cellular uptake by hepatocytes, liver sinusoidal endothelial cells and hepatic stellate cells. This phenomenon can be applied as a camouflage strategy by precoating EVs with albumin to fabricate the albumin-enriched protein corona-EV complex, enhancing non-phagocytic uptake in the liver. This work addresses a critical challenge facing intravenously administered EVs for liver therapy by tailoring the protein corona-EV complex for liver cell targeting and immune evasion.

Graphene Oxide (GO) for the Treatment of Bone Cancer: A Systematic Review and Bibliometric Analysis

Cancer is a severe disease that, in 2022, caused more than 9.89 million deaths worldwide. One worrisome type of cancer is bone cancer, such as osteosarcoma and Ewing tumors, which occur more frequently in infants. This study shows an active interest in the use of graphene oxide and its derivatives in therapy against bone cancer. We present a systematic review analyzing the current state of the art related to the use of GO in treating osteosarcoma, through evaluating the existing literature. In this sense, studies focused on GO-based nanomaterials for potential applications against osteosarcoma were reviewed, which has revealed that there is an excellent trend toward the use of GO-based nanomaterials, based on their thermal and anti-cancer activities, for the treatment of osteosarcoma through various therapeutic approaches. However, more research is needed to develop highly efficient localized therapies. It is suggested, therefore, that photodynamic therapy, photothermal therapy, and the use of nanocarriers should be considered as non-invasive, more specific, and efficient alternatives in the treatment of osteosarcoma. These options present promising approaches to enhance the effectiveness of therapy while also seeking to reduce side effects and minimize the damage to surrounding healthy tissues. The bibliometric analysis of photothermal and photochemical treatments of graphene oxide and reduced graphene oxide from January 2004 to December 2022 extracted 948 documents with its search strategy, mainly related to research papers, review papers, and conference papers, demonstrating a high-impact field supported by the need for more selective and efficient bone cancer therapies. The central countries leading the research are the United States, Iran, Italy, Germany, China, South Korea, and Australia, with strong collaborations worldwide. At the same time, the most-cited papers were published in journals with impact factors of more than 6.0 (2021), with more than 290 citations. Additionally, the journals that published the most on the topic are high impact factor journals, according to the analysis performed, demonstrating the high impact of the research field.

Protein-Based Nanocarriers and Nanotherapeutics for Infection and Inflammation

Infectious and inflammatory diseases are one of the leading causes of death globally. The status quo has become more prominent with the onset of the coronavirus disease 2019 (COVID-19) pandemic. To combat these potential crises, proteins have been proven as highly efficacious drugs, drug targets, and biomarkers. On the other hand, advancements in nanotechnology have aided efficient and sustained drug delivery due to their nano-dimension-acquired advantages. Combining both strategies together, the protein nanoplatforms are equipped with the advantageous intrinsic properties of proteins as well as nanoformulations, eloquently changing the field of nanomedicine. Proteins can act as carriers, therapeutics, diagnostics, and theranostics in their nanoform as fusion proteins or as composites with other organic/inorganic materials. Protein-based nanoplatforms have been extensively explored to target the major infectious and inflammatory diseases of clinical concern. The current review comprehensively deliberated proteins as nanocarriers for drugs and nanotherapeutics for inflammatory and infectious agents, with special emphasis on cancer and viral diseases. A plethora of proteins from diverse organisms have aided in the synthesis of protein-based nanoformulations. The current study specifically presented the proteins of human and pathogenic origin to dwell upon the field of protein nanotechnology, emphasizing their pharmacological advantages. Further, the successful clinical translation and current bottlenecks of the protein-based nanoformulations associated with the infection-inflammation paradigm have also been discussed comprehensively. SIGNIFICANCE STATEMENT: This review discusses the plethora of promising protein-based nanocarriers and nanotherapeutics explored for infectious and inflammatory ailments, with particular emphasis on protein nanoparticles of human and pathogenic origin with reference to the advantages, ADME (absorption, distribution, metabolism, and excretion parameters), and current bottlenecks in development of protein-based nanotherapeutic interventions.

Enhancing biofilm penetration and antibiofilm efficacy with protein nanocarriers against pathogenic biofilms

Nanocarriers play an important role in enhancing the efficacy of antibiotics against biofilms by improving their penetration and prolonging retention in pathogenic biofilms. Herein, the multifunctional nanocarriers including nanospheres (NS) and nanotubes (NT) with a high biocompatibility and biodegradability were prepared through self-assembly of partially hydrolyzed α-lactalbumin. The effects of these two different shaped nanocarriers on the delivery of antibiotics for biofilm treatment were examined by conducting in vitro antibiofilm experiment and in vivo infected wound model. The strong affinity of NS and NT for the bacterial surface allows antibiotics to be concentrated in the bacteria. Notably, the high permeability of NT into biofilms facilitates deeper penetration and the easier diffusion of loaded antibiotics within the biofilm. Furthermore, the acidic biofilm environment triggers the release of antibiotics from the NT, resulting in the accumulation of high local antibiotic concentrations. Therefore, NT could efficiently clean and inhibit the biofilm formation while also destroying the mature biofilms. In a S. aureus infected wound animal model, treatment with antibiotic-loaded NT demonstrated accelerated healing of S. aureus infected wounds when compared to free antibiotic treatment. These findings indicate that NT nanocarrier strategy is promising for treating bacterial biofilm infections, offering the potential for lower antibiotics dosages and preventing the overuse of antibiotics.

Multifunctional nanoparticle-mediated combining therapy for human diseases

Combining existing drug therapy is essential in developing new therapeutic agents in disease prevention and treatment. In preclinical investigations, combined effect of certain known drugs has been well established in treating extensive human diseases. Attributed to synergistic effects by targeting various disease pathways and advantages, such as reduced administration dose, decreased toxicity, and alleviated drug resistance, combinatorial treatment is now being pursued by delivering therapeutic agents to combat major clinical illnesses, such as cancer, atherosclerosis, pulmonary hypertension, myocarditis, rheumatoid arthritis, inflammatory bowel disease, metabolic disorders and neurodegenerative diseases. Combinatorial therapy involves combining or co-delivering two or more drugs for treating a specific disease. Nanoparticle (NP)-mediated drug delivery systems, i.e., liposomal NPs, polymeric NPs and nanocrystals, are of great interest in combinatorial therapy for a wide range of disorders due to targeted drug delivery, extended drug release, and higher drug stability to avoid rapid clearance at infected areas. This review summarizes various targets of diseases, preclinical or clinically approved drug combinations and the development of multifunctional NPs for combining therapy and emphasizes combinatorial therapeutic strategies based on drug delivery for treating severe clinical diseases. Ultimately, we discuss the challenging of developing NP-codelivery and translation and provide potential approaches to address the limitations. This review offers a comprehensive overview for recent cutting-edge and challenging in developing NP-mediated combination therapy for human diseases.

Understanding protein-nanoparticle interactions leading to protein corona formation: In vitro - in vivo correlation study

Nanoparticles (NPs) in contact with biological fluids form a biomolecular corona through interactions with proteins, lipids, and sugars, acquiring new physicochemical properties. This work explores the interaction between selected proteins (hemoglobin and fetuin-A) that may alter NP circulation time and NPs of different surface charges (neutral, positive, and negative). The interaction with key proteins albumin and transferrin, the two of the most abundant proteins in plasma was also studied. Binding affinity was investigated using quartz crystal microbalance and fluorescence quenching, while circular dichroism assessed potential conformational changes. The data obtained from in vitro experiments were compared to in vivo protein corona data. The results indicate that electrostatic interactions primarily drive protein-NP interactions, and higher binding affinity does not necessarily translate into more significant structural changes. In vitro and single protein-NP studies provide valuable insights that can be correlated with in vivo observations, opening exciting possibilities for future protein corona studies.

Unleashing the Potential: Designing Antibody-Targeted Lipid Nanoparticles for Industrial Applications with CMC Considerations and Clinical Outlook

Antibody-targeted lipid nanoparticles (Ab-LNPs) are rapidly gaining traction as multifaceted platforms in precision medicine, adept at delivering a diverse array of therapeutic agents, including nucleic acids and small molecules. This review provides an incisive overview of the latest developments in the field of Ab-LNP technology, with a special emphasis on pivotal design aspects such as antibody engineering, bioconjugation strategies, and advanced formulation techniques. Furthermore, it addresses critical chemistry, manufacturing, and controls (CMC) considerations and thoroughly examines the in vivo dynamics of Ab-LNPs, underscoring their promising potential for clinical application. By seamlessly blending scientific advancements with practical industrial perspectives, this review casts a spotlight on the burgeoning role of Ab-LNPs as an innovative and potent tool in the realm of targeted drug delivery.

Fixation and Visualization of Full Protein Corona on Lipid Surface of Composite Nanoconstruction

Spontaneous sorption of proteins on the nanoparticles' surface leads to the fact that nanoparticles in biological media are always enveloped by a layer of proteins-the protein corona. Corona proteins affect the properties of nanoparticles and their behavior in a biological environment. In this regard, knowledge about the composition of the corona is a necessary element for the development of nanomedicine. Because proteins have different sorption efficacy, isolating particles with a full corona and characterizing the full corona is challenging. In this study, we propose a photo-activated cross-linker for full protein corona fixation. We believe that the application of our proposed approach will make it possible to capture and visualize the full corona on nanoparticles coated with a lipid shell.

Ginsenoside Rg3 endows liposomes with prolonged blood circulation and reduced accelerated blood clearance

PEGylated cholesterol-containing liposomes (Chol-PEG-lipo) have been widely used as a drug carrier for their good stealth property in blood circulation where cholesterol maintains the stability of the liposomal lipid bilayer and PEGylation endows liposomes with long circulation capability. However, cholesterol-related disadvantages and the accelerated blood clearance (ABC) phenomenon caused by PEGylation greatly limit the application of conventional stealth liposomes in clinic. Herein, ginsenoside Rg3 was selected to substitute cholesterol and PEG for liposomes preparation (Rg3-lipo). Rg3 was proved with similar liposomal membrane regulation ability to cholesterol and comparable long circulation effect to PEG. In addition, repeated administrations of Chol-PEG-lipo and Rg3-lipo were performed. The circulation time of the second dose of Chol-PEG-lipo was substantially reduced accompanied by a greatly increased accumulation in the liver due to the induction of anti-PEG IgM and the subsequent activated complement system. In contrast, no significantly increased level of relative plasma cells, IgM secretion and the complement activation in blood circulation was observed after the second injection of Rg3-lipo. As a result, Rg3-lipo showed great stealth property without ABC phenomenon. Therefore, developing liposomes utilizing Rg3 instead of PEG and cholesterol presents a promising strategy to prolong the blood circulation time of liposomes without triggering the ABC phenomenon and activated immune responses.

Nano-bio interactions in mRNA nanomedicine: Challenges and opportunities for targeted mRNA delivery

Upon entering the biological milieu, nanomedicines swiftly interact with the surrounding tissue fluid, subsequently being enveloped by a dynamic interplay of biomacromolecules, such as carbohydrates, nucleic acids, and cellular metabolites, but with predominant serum proteins within the biological corona. A notable consequence of the protein corona phenomenon is the unintentional loss of targeting ligands initially designed to direct nanomedicines toward particular cells or organs within the in vivo environment. mRNA nanomedicine displays high demand for specific cell and tissue-targeted delivery to effectively transport mRNA molecules into target cells, where they can exert their therapeutic effects with utmost efficacy. In this review, focusing on the delivery systems and tissue-specific applications, we aim to update the nanomedicine population with the prevailing and still enigmatic paradigm of nano-bio interactions, a formidable hurdle in the pursuit of targeted mRNA delivery. We also elucidate the current impediments faced in mRNA therapeutics and, by contemplating prospective avenues-either to modulate the corona or to adopt an 'ally from adversary' approach-aim to chart a course for advancing mRNA nanomedicine.

Peptide Orientation Strongly Affected by the Nanoparticle Size as Revealed by Sum Frequency Scattering Spectroscopy

The orientation of proteins at interfaces has a profound effect on the function of proteins. For nanoparticles (NPs) in a biological environment, protein orientation determines the toxicity, function, and identity of the NP. Thus, understanding how proteins orientate at NP surfaces is a critical parameter in controlling NP biochemistry. While planar surfaces are often used to model NP interfaces for protein orientation studies, it has been shown recently that proteins can orient very differently on NP surfaces. This study uses sum frequency scattering vibrational spectroscopy of the model helical leucine-lysine (LK) peptide on NPs of different sizes to determine the cause for the orientation effects. The data show that, for low dielectric constant materials, the orientation of the helical LK peptide is a function of the coulombic forces between peptides across different particle volumes. This finding strongly suggests that flat model systems are only of limited use for determining protein orientation at NP interfaces and that charge interactions should be considered when designing medical NPs or assessing NP biocompatibility.

Pulmonary endothelium-targeted nanoassembly of indomethacin and superoxide dismutase relieves lung inflammation

Lung inflammation is an essential inducer of various diseases and is closely related to pulmonary-endothelium dysfunction. Herein, we propose a pulmonary endothelium-targeted codelivery system of anti-inflammatory indomethacin (IND) and antioxidant superoxide dismutase (SOD) by assembling the biopharmaceutical SOD onto the "vector" of rod-like pure IND crystals, followed by coating with anti-ICAM-1 antibody (Ab) for targeting endothelial cells. The codelivery system has a 237 nm diameter in length and extremely high drug loading of 39% IND and 2.3% SOD. Pharmacokinetics and biodistribution studies demonstrate the extended blood circulation and the strong pulmonary accumulation of the system after intravenous injection in the lipopolysaccharide (LPS)-induced inflammatory murine model. Particularly, the system allows a robust capacity to target pulmonary endothelium mostly due to the rod-shape and Ab coating effect. In vitro, the preparation shows the synergistic anti-inflammatory and antioxidant effects in LPS-activated endothelial cells. In vivo, the preparation exhibits superior pharmacodynamic efficacy revealed by significantly downregulating the inflammatory/oxidative stress markers, such as TNF-α, IL-6, COX-2, and reactive oxygen species (ROS), in the lungs. In conclusion, the codelivery system based on rod-like pure crystals could well target the pulmonary endothelium and effectively alleviate lung inflammation. The study offers a promising approach to combat pulmonary endothelium-associated diseases.

A Targeted Exosome Therapeutic Confers Both CfDNA Scavenging and Macrophage Polarization for Ameliorating Rheumatoid Arthritis

Only a minority of rheumatoid arthritis (RA) patients achieve disease remission, so the exploration of additional pathogenic factors and the development of new therapeutics are needed. Here, strong correlations among the cell-free DNA (cfDNA) level and the inflammatory response in clinical synovial fluid samples and RA disease activity are discovered. The important role of cfDNA in disease development in a collagen-induced arthritis (CIA) murine model is also demonstrated. Building on these findings, a novel therapeutic based on anti-inflammatory (M2) macrophage-derived exosomes as chassis, that are modified with both oligolysine and matrix metalloproteinase (MMP)-cleavable polyethylene glycol (PEG) on the membrane, is developed. After intravenous injection, PEG-enabled prolonged circulation and C─C motif chemokine ligand-directed accumulation together result in enrichment at inflamed joints. Following subsequent MMP cleavage, the positively charged oligolysine is exposed for cfDNA scavenging, while exosomes induce M2 polarization. By using a classical CIA murine model and a newly established CIA canine model, it is demonstrated that the rationally designed exosome therapeutic substantially suppresses inflammation in joints and provides strong chondroprotection and osteoprotection, revealing its potential for effective CIA amelioration.

Protein corona on brain targeted nanocarriers: Challenges and prospects

Safe and efficient medical therapy for brain diseases is still an unmet clinical need due to various barriers represented by the blood-brain barrier. Well-designed brain targeted nanocarriers are potential solutions for enhanced brain drug delivery; however, the complicated in vivo process attenuates performance of nanocarriers, which severely hampers clinical translation. The formation of protein corona (PC) is inevitable for nanocarriers circulation and transport in biofluids, acting as an important factor to regulate in vivo performance of nanocarriers. In this review, the reported strategies have been retrospected for better understanding current situation in developing brain targeted nanocarriers. The interplay between brain targeted nanocarriers and plasma proteins is emphasized to comprehend how the nanocarriers adsorb proteins by certain synthetic identity, and following regulations on in vivo performance of nanocarriers. More importantly, the mainstream methods to promote efficiency of nanocarriers by regulating PC, defined as in vitro functionalization and in vivo functionalization strategies, are also discussed. Finally, viewpoints about future development of brain targeted nanocarriers according to the understanding on nanocarriers-PC interaction are proposed.

Current research trends of nanomedicines

Owing to the inherent shortcomings of traditional therapeutic drugs in terms of inadequate therapeutic efficacy and toxicity in clinical treatment, nanomedicine designs have received widespread attention with significantly improved efficacy and reduced non-target side effects. Nanomedicines hold tremendous theranostic potential for treating, monitoring, diagnosing, and controlling various diseases and are attracting an unfathomable amount of input of research resources. Against the backdrop of an exponentially growing number of publications, it is imperative to help the audience get a panorama image of the research activities in the field of nanomedicines. Herein, this review elaborates on the development trends of nanomedicines, emerging nanocarriers, in vivo fate and safety of nanomedicines, and their extensive applications. Moreover, the potential challenges and the obstacles hindering the clinical translation of nanomedicines are also discussed. The elaboration on various aspects of the research trends of nanomedicines may help enlighten the readers and set the route for future endeavors.

Protein Labeling Facilitates the Understanding of Protein Corona Formation via Fluorescence Resonance Energy Transfer and Fluorescence Correlation Spectroscopy

Once nanoparticles enter into the biological milieu, nanoparticle-biomacromolecule complexes, especially the protein corona, swiftly form, which cause obvious effects on the physicochemical properties of both nanoparticles and proteins. Here, the thermodynamic parameters of the interactions between water-soluble GSH-CdSe/ZnS core/shell quantum dots (GSH-QDs) and human serum albumin (HSA) were investigated with the aid of labeling fluorescence of HSA. It was proved that the labeling fluorescence originating from a fluorophore (BDP-CN for instance) could be used to investigate the interactions between QDs and HSA. Gel electrophoresis displayed that the binding ratio between HSA and QDs was ∼2:1 by direct visualization. Fluorescence resonance energy transfer (FRET) results indicated that the distance between the QDs and the fluorophore BDP-CN in HSA was 7.2 nm, which indicated that the distance from the fluorophore to the surface of the QDs was ∼4.8 nm. Fluorescence correlation spectroscopy (FCS) results showed that HSA formed a monolayer of a protein corona with a thickness of 5.5 nm. According to the spatial structure of HSA, we could speculate that the binding site of QDs was located at the side edge (not the triangular plane) of HSA with an equilateral triangular prism. The elaboration of the thermodynamic parameters, binding ratio, and interaction orientation will highly improve the fundamental understanding of the formation of protein corona. This work has guiding significance for the exploration of the interactions between proteins and nanomaterials.

ROS-producing nanomaterial engineered from Cu(I) complexes with P2N2-ligands for cancer cells treating

The work presents core-shell nanoparticles (NPs) built from the novel Cu(I) complexes with cyclic P2N2-ligands (1,5-diaza-3,7-diphosphacyclooctanes) that can visualize their entry into cancer and normal cells using a luminescent signal and treat cells by self-enhancing generation of reactive oxygen species (ROS). Variation of P- and N-substituents in the series of P2N2-ligands allows structure optimization of the Cu(I) complexes for the formation of the luminescent NPs with high chemical stability. The non-covalent modification of the NPs with triblock copolymer F-127 provides their high colloidal stability, followed by efficient cell internalization of the NPs visualized by their blue (⁓450 nm) luminescence. The cytotoxic effects of the NPs toward the normal and some of cancer cells are significantly lower than those of the corresponding molecular complexes, which correlates with the chemical stability of the NPs in the solutions. The ability of the NPs to self-enhanced and H2O2-induced ROS generation is demonstrated in solutions and intracellular space by means of the standard electron spin resonance (ESR) and fluorescence techniques correspondingly. The anticancer specificity of the NPs toward HuTu 80 cancer cells and the apoptotic cell death pathway correlate with the intracellular level of ROS, which agrees well with the self-enhancing ROS generation of the NPs. The enhanced level of ROS revealed in HuTu 80 cells incubated with the NPs can be associated with the significant level of their mitochondrial localization.

On the mechanism of tissue-selective gene delivery by lipid nanoparticles

The era of nucleic acid nanomedicine has arrived, as evidenced by Patisiran, a small interfering RNA (siRNA) encapsulated lipid nanoparticle (LNP), and mRNA-loaded LNPs used in COVID-19 vaccines. The diversity of nano-designs for delivering nucleic acid molecules tested in Phase II/III clinical trials reflects the potential of these technologies. These breakthroughs in non-viral gene delivery, including the use of LNPs, have attracted substantial interest worldwide for developing more effective drugs. A next step in this field is to target tissues other than the liver, which requires significant research efforts and material development. However, mechanistic studies in this area are lacking. This study compares two types of LNPs with different tissue-selectivity for delivering plasmid DNA (pDNA), one being liver-selective and the other spleen-selective, in an effort to understand the mechanisms responsible for differences in gene expression of delivered genes. We observed little difference in the biodistribution of these two LNPs despite the 100-1000-fold differences in gene expression. We then quantified the amount of delivered pDNA and mRNA expression in each tissue by quantitative real-time PCR (qPCR) to evaluate various intracellular processes, such as nuclear delivery, transcription and translation. The results showed a >100-fold difference in the translation step but there were little differences in amount of pDNA delivered to the nucleus or the amount of mRNA expression for the two LNP deliveries. Our findings suggest that endogenous factors affect gene expression efficiency not the extent of biodistribution.

Lipid carriers for mRNA delivery

Messenger RNA (mRNA) is the template for protein biosynthesis and is emerging as an essential active molecule to combat various diseases, including viral infection and cancer. Especially, mRNA-based vaccines, as a new type of vaccine, have played a leading role in fighting against the current global pandemic of COVID-19. However, the inherent drawbacks, including large size, negative charge, and instability, hinder its use as a therapeutic agent. Lipid carriers are distinguishable and promising vehicles for mRNA delivery, owning the capacity to encapsulate and deliver negatively charged drugs to the targeted tissues and release cargoes at the desired time. Here, we first summarized the structure and properties of different lipid carriers, such as liposomes, liposome-like nanoparticles, solid lipid nanoparticles, lipid-polymer hybrid nanoparticles, nanoemulsions, exosomes and lipoprotein particles, and their applications in delivering mRNA. Then, the development of lipid-based formulations as vaccine delivery systems was discussed and highlighted. Recent advancements in the mRNA vaccine of COVID-19 were emphasized. Finally, we described our future vision and perspectives in this field.

Getting fat and stressed: Effects of dietary intake of titanium dioxide nanoparticles in the liver of turbot Scophthalmus maximus

The extensive use of nanomaterials, including titanium dioxide nanoparticles (TiO2 NPs), raises concerns about their persistence in ecosystems. Protecting aquatic ecosystems and ensuring healthy and safe aquaculture products requires the assessment of the potential impacts of NPs on organisms. Here, we study the effects of a sublethal concentration of citrate-coated TiO2 NPs of two different primary sizes over time in flatfish turbot, Scophthalmus maximus (Linnaeus, 1758). Bioaccumulation, histology and gene expression were assessed in the liver to address morphophysiological responses to citrate-coated TiO2 NPs. Our analyses demonstrated a variable abundance of lipid droplets (LDs) in hepatocytes dependent on TiO2 NPs size, an increase in turbot exposed to smaller TiO2 NPs and a depletion with larger TiO2 NPs. The expression patterns of genes related to oxidative and immune responses and lipid metabolism (nrf2, nfκb1, and cpt1a) were dependent on the presence of TiO2 NPs and time of exposure supporting the variance in hepatic LDs distribution over time with the different NPs. The citrate coating is proposed as the likely catalyst for such effects. Thus, our findings highlight the need to scrutinize the risks associated with exposure to NPs with distinct properties, such as primary size, coatings, and crystalline forms, in aquatic organisms.

The interplay between PEGylated nanoparticles and blood immune system

During the last two decades, an increasing number of reports have pointed out that the immunogenicity of polyethylene glycol (PEG) may trigger accelerated blood clearance (ABC) and hypersensitivity reaction (HSR) to PEGylated nanoparticles, which could make PEG modification counterproductive. These phenomena would be detrimental to the efficacy of the load and even life-threatening to patients. Consequently, further elucidation of the interplay between PEGylated nanoparticles and the blood immune system will be beneficial to developing and applying related formulations. Many groups have worked to unveil the relevance of structural factors, dosing schedule, and other factors to the ABC phenomenon and hypersensitivity reaction. Interestingly, the results of some reports seem to be difficult to interpret or contradict with other reports. In this review, we summarize the physiological mechanisms of PEG-specific immune response. Moreover, we speculate on the potential relationship between the induction phase and the effectuation phase to explain the divergent results in published reports. In addition, the role of nanoparticle-associated factors is discussed based on the classification of the action phase. This review may help researchers to develop PEGylated nanoparticles to avoid unfavorable immune responses based on the underlying mechanism.

Cholesterol modulates the physiological response to nanoparticles by changing the composition of protein corona

Nanoparticles (NPs) in biological fluids form a layer of biomolecules known as the protein corona. The protein corona has been shown to determine the biological identity and in vivo fate of NPs, but whether and how metabolites, especially disease-related small molecules, regulate the protein corona and subsequently impact NP fate in vivo is relatively poorly understood. Here we report on the effects of cholesterol on the generation of protein corona and subsequent effects. We find that high levels of cholesterol, as in hypercholesterolemia, result in a protein corona with enriched apolipoproteins and reduced complement proteins by altering the binding affinity of the proteins to the NPs. The cholesterol-mediated protein corona can induce stronger inflammatory responses to NPs in macrophages and promote the cellular uptake of NPs in hepatocytes by enhancing the recognition of lipoprotein receptors when compared with normal protein corona. The result of in vivo biodistribution assays shows that, compared with healthy mice, NPs in hypercholesterolemic mice were more likely to be delivered to the liver, spleen and brain, and less likely to be delivered to the lungs. Our findings reveal that the metabolome profile is an unexploited factor impacting the target efficacy and safety of nanomedicines, providing a way to develop personalized nanomedicines by harnessing disease-related metabolites.

Selective organ targeting nanoparticles: from design to clinical translation

Targeting nanoparticle is a very promising therapeutic approach that can precisely target specific sites to treat diseases. Research on nanoscale drug delivery systems has made great progress in the past few years, making targeting nanoparticles a promising prospect. However, selective targeting nanoparticles designed for specific organs still face several challenges, one of which is the unknown fate of nanoparticles in vivo. This review starts with the in vivo journey of nanoparticles and describes the biological barriers and some targeting strategies for nanoparticles to target specific organs. Then, through the collection of literature in recent years, the design of selective targeting nanoparticles for various organs is illustrated, which provides a reference strategy for people to study the design of selective organ targeting nanoparticles. Ultimately, the prospect and challenge of selective organ targeting nanoparticles are discussed by collecting the data of clinical trials and marketed drugs.

FRET-based analysis on the structural stability of polymeric micelles: Another key attribute beyond PEG coverage and particle size affecting the blood clearance

Various attributes of micelles, such as PEG density and particle size, are considered to be related to blood clearance. The structural stability of micelles is another key attribute that will affect the in vivo fate. This study employed fluorescence resonance energy transfer (FRET) analysis to guide the preparation of polymeric micelles with different structural stability. Micelles prepared using copolymers with longer hydrophobic blocks showed higher structural stability; emulsification was a better method than nanoprecipitation to prepare stable micelles. The fast chain exchange kinetics and the high-water content of micellar cores explained the low structural stability of those micelles. Moreover, this study highlighted the importance of structural stability that affected blood clearance in concert with PEG length and particle size. One-third of the small and stable micelles were detected in the blood 24 h after injection. While unstable micelles would be cleared from the circulation within 4 h. Notably, there would be a threshold of structural stability. Micelles with structural stability below this threshold were quickly cleared even if they possessed a longer PEG length and a smaller size. In contrast, higher structural stability allowed polymeric micelles to maintain higher integrity in vivo and enhance tumor accumulation and anti-tumor efficacy. In conclusion, this study systematically analyzed the importance of the structural stability of micelles on the in vivo fate.

DPA-Zinc around Polyplexes Acts Like PEG to Reduce Protein Binding While Targeting Cancer Cells

Gene therapy holds great promise as an effective treatment for many diseases of genetic origin. Gene therapy works by employing cationic polymers, liposomes, and nanoparticles to condense DNA into polyplexes via electronic interactions. Then, a therapeutic gene is introduced into target cells, thereby restoring or changing cellular function. However, gene transfection efficiency remains low in vivo due to high protein binding, poor targeting ability, and substantial endosomal entrapment. Artificial sheaths containing PEG, anions, or zwitterions can be introduced onto the surface of gene carriers to prevent interaction with proteins; however, they reduce the cellular uptake efficacy, endosomal escape, targeting ability, thereby, lowering gene transfection. Here, it is reported that linking dipicolylamine-zinc (DPA-Zn) ions onto polyplex nanoparticles can produce a strong hydration water layer around the polyplex, mimicking the function of PEGylation to reduce protein binding while targeting cancer cells, augmenting cellular uptake and endosomal escape. The polyplexes with a strong hydration water layer on the surface can achieve a high gene transfection even in a 50% serum environment. This strategy provides a new solution for preventing protein adsorption while improving cellular uptake and endosomal escape.

Lipid Corona Formation on Micro- and Nanoplastic Particles Modulates Uptake and Toxicity in A549 Cells

Plastic waste is a global issue leaving no continents unaffected. In the environment, ultraviolet radiation and shear forces in water and land contribute to generating micro- and nanoplastic particles (MNPP), which organisms can easily take up. Plastic particles enter the human food chain, and the accumulation of particles within the human body is expected. Crossing epithelial barriers and cellular uptake of MNPP involves the interaction of plastic particles with lipids. To this end, we generated unilamellar vesicles from POPC (1-palmitoyl-2-oleoyl-glycero-3-phosphocholine) and POPS (1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-L-serine) and incubated them with pristine, carboxylated, or aminated polystyrene spheres (about 1 µm in diameter) to generate lipid coronas around the particles. Lipid coronas enhanced the average particle sizes and partially changed the MNPP zeta potential and polydispersity. In addition, lipid coronas led to significantly enhanced uptake of MNPP particles but not their cytotoxicity, as determined by flow cytometry. Finally, adding proteins to lipid corona nanoparticles further modified MNPP uptake by reducing the uptake kinetics, especially in pristine and carboxylated plastic samples. In conclusion, our study demonstrates for the first time the impact of different types of lipids on differently charged MNPP particles and the biological consequences of such modifications to better understand the potential hazards of plastic exposure.

Cancer Nanomedicine: Emerging Strategies and Therapeutic Potentials

Cancer continues to pose a severe threat to global health, making pursuing effective treatments more critical than ever. Traditional therapies, although pivotal in managing cancer, encounter considerable challenges, including drug resistance, poor drug solubility, and difficulties targeting tumors, specifically limiting their overall efficacy. Nanomedicine's application in cancer therapy signals a new epoch, distinguished by the improvement of the specificity, efficacy, and tolerability of cancer treatments. This review explores the mechanisms and advantages of nanoparticle-mediated drug delivery, highlighting passive and active targeting strategies. Furthermore, it explores the transformative potential of nanomedicine in tumor therapeutics, delving into its applications across various treatment modalities, including surgery, chemotherapy, immunotherapy, radiotherapy, photodynamic and photothermal therapy, gene therapy, as well as tumor diagnosis and imaging. Meanwhile, the outlook of nanomedicine in tumor therapeutics is discussed, emphasizing the need for addressing toxicity concerns, improving drug delivery strategies, enhancing carrier stability and controlled release, simplifying nano-design, and exploring novel manufacturing technologies. Overall, integrating nanomedicine in cancer treatment holds immense potential for revolutionizing cancer therapeutics and improving patient outcomes.

Meta-analysis of material properties influencing nanoparticle plasma pharmacokinetics

Thorough characterization of the plasma pharmacokinetics (PK) is a critical step in clinical development of novel therapeutics and is routinely performed for small molecules and biologics. However, there is a paucity of even basic characterization of PK for nanoparticle-based drug delivery systems. This has led to untested generalizations about how nanoparticle properties govern PK. Here, we present a meta-analysis of 100 nanoparticle formulations following IV administration in mice to identify any correlations between four PK parameters derived by non-compartmental analysis (NCA) and four cardinal properties of nanoparticles: PEGylation, zeta potential, size, and material. There was a statistically significant difference between the PK of particles stratified by nanoparticle properties. However, single linear regression between these properties and PK parameters showed poor predictability (r2 < 0.10 for all analyses), while multivariate regressions showed improved predictability (r2 > 0.38, except for t1/2). This suggests that no single nanoparticle property alone is even moderately predictive of PK, while the combination of multiple nanoparticle features does provide moderate predictive power. Improved reporting of nanoparticle properties will enable more accurate comparison between nanoformulations and will enhance our ability to predict in vivo behavior and design optimal nanoparticles.