Nanomedicine: Nanotechnology, Biology and Medicine - Articles in Press

Nanoparticles induce platelet activation in vitro through stimulation of canonical signalling pathways - Uncorrected Proof

2012-04-27

Abstract: Nanomaterials are attracting growing interest for their potential use in several applications as nanomedicine; therefore, the analysis of their potential toxic effects on various cellular models, including circulating blood cells, is mandatory. This study aimed to investigate the effect of three unrelated nanomaterials, namely nanoscale silica, multiwalled carbon nanotubes, and carbon black, on platelet activation and aggregation. We found that these nanomaterials stimulate some of the typical biochemical pathways involved in canonical platelet activation, such as the stimulation of phospholipase C and Rap1b, resulting in the integrin αIIbβ3-mediated platelet aggregation, through a mechanism largely dependent on the release of the extracellular second messengers ADP and thromboxane A2. Importantly, we found that doses of nanoparticles unable to trigger appreciable responses can synergize with subthreshold amounts of physiological agonists to mediate platelet aggregation, indicating that even small amounts of nanomaterials in the bloodstream might contribute to the development of thrombosis.Graphical Abstract: Exposure of platelets to Hi-Sil T700TM, multiwalled carbon nanotubes (MWCNT), or carbon black promotes stimulation of canonical signalling pathways that involve the activation of phospholipase C (PLC), protein kinase C (PKC), and the small GTPase Rap1. Platelet activation is supported by the release of the extracellular second messengers ADP and thromboxane A2 (TxA2), that cooperate with nanomaterials to promote integrin αIIbβ3-dependent platelet aggregation.

Human serum albumin-coated lipid nanoparticles for delivery of siRNA to breast cancer - Uncorrected Proof

2012-04-27

Abstract: Human serum albumin (HSA)-coated lipid nanoparticles (HSA-LNPs) loaded with phrGFP-targeted siRNA (HSA-LNPs-siRNA) were prepared and evaluated for gene downregulation effect in phrGFP-transfected breast cancer cells and the corresponding xenograft tumor model. HSA-LNPs-siRNA were successfully prepared with a particle size of 79.5±5.5 nm. In phrGFP-transfected MCF-7 cells, HSA-LNPs-siRNA significantly decreased cell fluorescence even in the presence of FBS. Moreover, cell fluorescence and phrGFP mRNA expression were significantly downregulated by HSA-LNPs-siRNA in phrGFP-transfected MCF-7, MDA-MB-231, and SK-BR-3 cells in comparison with control or HSA-LNPs-siRNA (scrambled). In phrGFP-transfected MCF-7 xenograft tumor model, tumor fluorescence was significantly decreased after three IV administrations of HSA-LNPs-siRNA at a dose of 3 mg/kg in comparison with siRNA alone. HSA-LNPs-siRNA demonstrated a superior pharmacokinetic profile in comparison with siRNA at a dose of 1mg/kg. These results show that the novel nonviral carrier, HSA-LNPs, may be used for the delivery of siRNA to breast cancer cells.Graphical abstract:

Enhancement of cell permeabilization apoptosis-inducing activity of selenium nanoparticles by ATP surface decoration - Uncorrected Proof

Yibo Zhang, Xiaoling Li, Zhi Huang, Wenjie Zheng, Cundong Fan, Tianfeng Chen — 2012-04-27

Abstract: A simple method for preparation of adenosine triphosphate (ATP) surface-functionalized selenium nanoparticles (SeNPs@ATP) with enhanced cell permeabilization and anticancer activity has been demonstrated in the study reported in this article. Spherical SeNPs were decorated with ATP by strong adsorption through an Se-N bond, leading to the highly stable structure of the conjugates. ATP surface decoration significantly enhanced the cellular uptake and anticancer activity of SeNPs. Induction of apoptosis in HepG2 human hepatocellular carcinoma cells by SeNPs@ATP was evidenced by accumulation of the sub-G1 cell population, phosphatidylserine exposure, DNA fragmentation, PARP cleavage and caspase activation. Further studies found that SeNPs@ATP treatment triggered the depletion of mitochondrial membrane potential and reactive oxygen species (ROS) overproduction. Our results demonstrate that the use of ATP as a surface decorator of SeNPs is a novel strategy to achieve anticancer synergism. SeNPs@ATP may be a candidate for further evaluation as a chemotherapeutic agent for human cancers.Graphical abstract: ATP surface decoration significantly enhances the cellular uptake and anticancer activity of SeNPs. Induction of apoptosis was the major mode of cancer cell death induced by SeNPs@ATP. Our results demonstrate that it is a novel strategy to use ATP as a surface decorator of SeNPs to achieve anticancer synergism. SeNPs@ATP may be a candidate for further evaluation as a therapeutic agent for human cancers.

Surface modification of PAMAM dendrimer improves its biocompatibility - Uncorrected Proof

2012-04-27

Abstract: Modification of dendrimer surface groups is one of the methods available to obtain compounds characterized by reduced toxicity. This article reports results of preliminary biocompatibility studies of a modified polyamidoamine dendrimer of the fourth generation. Reaction with dimethyl itaconate resulted in transformation of surface amine groups into pyrrolidone derivatives. Interaction of the modified dendrimer with human serum albumin (HSA) was analyzed. The influence of the dendrimer on mouse neuroblastoma cell line viability and its hemolytic properties were also investigated. The binding constant between analyzed dendrimer and HSA was found to be equal to 1.2 × 105 ± 0.2 × 105 M–1. Small changes in HSA secondary structure were observed. The analyzed dendrimer revealed minor toxic activity, as diminishment in cell viability was observed only for dendrimer concentrations higher than 2 mg/mL. Moreover, under the applied experimental conditions, no hemolytic activity was observed. Those observations point to the potential of the analyzed compound for further studies toward its applicability in nanomedicine.Graphical abstract: This article reports results of preliminary biocompatibility studies of a modified PAMAM dendrimer of the fourth generation. By means of the reaction with dimethyl itaconate, surface amine groups of PAMAM dendrimer were transformed into pyrrolidone derivatives. Obtained compound showed no hemolytic activity and minor cytotoxicity. Observed properties of the G4 PAMAM-pyrolidone dendrimer predestinate this compound to further studies towards its applicability in nanomedicine.

Evaluation of SERS labeling of CD20 on CLL cells using optical microscopy and fluorescence flow cytometry - Uncorrected Proof

Christina M. MacLaughlin, Edward P.K. Parker, Gilbert C. Walker, Chen Wang — 2012-04-27

Abstract: Immunophenotyping of lymphoproliferative disorders depends on the effective measurement of cell surface markers. The inherent light-scattering properties of plasmonic nanoparticles (NPs) combined with recent developments in NP design may confer significant advantages over traditional fluorescence probes. We report and evaluate the use of surface-enhanced Raman scattering (SERS) gold NPs (AuNPs) conjugated to therapeutic rituximab antibodies for selective targeting of CD20 molecules. SERS AuNPs were prepared by adsorbing a Raman-active dye onto the surface of 60-nm spherical AuNPs, coating the particles with 5-kDa polyethylene glycol, and conjugating rituximab to functional groups on polyethylene glycol. The effective targeting of CD20 on chronic lymphocytic leukemia cells by rituximab-conjugated SERS AuNPs was evaluated by dark-field imaging, Raman spectroscopy, and flow cytometry with both competitive binding and fluorescence detection procedures. Evidence of CD20 clustering within approximately 100 nm was observed.Graphical Abstract: Polymer-coated SERS-active gold nanoparticles bound to anti-CD20 rituximab antibodies (center) specifically targeted CD20 receptor proteins on the surface of B lymphocytes in chronic lymphocytic leukemia samples. The binding of SERS probes to CD20 was detected using Raman spectroscopy to determine the presence of the particles'SERS signature in drops of cell suspension (left). Dark field microscopy was used to image intense Rayleigh scattering of the particles. The 60 nm SERS gold particles appear as green-gold dots bound over the surface of B-cells (right). SERS gold nanoparticle labeling was also compatible with, and had its specificity evaluated by fluorescence flow cytometry.

Interaction of inorganic nanoparticles with the skin barrier: current status and critical review - Uncorrected Proof

Hagar I. Labouta, Marc Schneider — 2012-04-27

Abstract: Integration of nanotechnology with biology leads to various advantages in applied pharmaceutical and medical sciences. In that regard, the behavior of nanoparticles (NPs) in relation to the skin, an important biological barrier, has been the target of several recent studies. Yet the potential ability of NPs to penetrate into the underlying viable tissue lies at the center of debate. This review briefly highlights the current applications of inorganic NPs, then discusses the current status of their skin penetration in view of the vast variation among the experimental setups in use. Determinants of particle penetration, adopted approaches for enhanced penetration, the underlying mechanism, as well as qualitative and quantitative analysis of NPs present in the skin are also within the scope of this review article. We emphasize analyzing the data generated from experiments on human skin, the “gold standard” for assessment of in vitro skin penetration. Based on this, we include some recommendations for future research.Graphical Abstract: Nanoparticles could remain on the skin surface (1), penetrate into the skin through intercellular pathways and localize in the stratum corneum (2) or even permeate the whole stratum corneum into deeper skin layers (3). On the other hand, hair follicles could act as a depot for particles (4) from where particles could further penetrate into deeper skin layers (5).

Poly(amidoamine) dendrimer-mediated synthesis and stabilization of silver sulfonamide nanoparticles with increased antibacterial activity - Corrected Proof

2012-04-05

Abstract: Silver sulfadiazine (AgSD) is a topical antibiotic with limited aqueous solubility. In this study, it was shown that poly(amido amine) (PAMAM) dendrimer complexes with SD (SDZ) and silver (Ag) could be used for a bottom-up approach to synthesize highly-soluble AgSD nanoparticles (NPs). These NPs were stabilized against crystal growth by electrostatic layer-by-layer (LBL) coating with various PAMAM dendrimers. Additionally, AgNPs can be incorporated in the dendrimer shells that augmented AgSD release. NP formulation in a cream base provided a topical drug-delivery platform with enhanced antibacterial properties against burn-wound infections, comprising three nanostructures i.e., nano-AgSD, AgNPs as well as PAMAM dendrimers, in one efficient, elegant nanosystem.Graphical Abstract: Topical formulations containing ternary nanoparticles compose of nanosized silver sulfadiazine, PAMAM dendrimers, and nano-silver showing increased antibacterial activity.

Site directed vascular gene delivery in vivo by ultrasonic destruction of magnetic nanoparticle coated microbubbles - Corrected Proof

2012-04-04

Abstract: Site specific vascular gene delivery for therapeutic implications is favorable because of reduction of possible side effects. Yet this technology faces numerous hurdles that result in low transfection rates because of suboptimal delivery. Combining ultrasonic microbubble technology with magnetic nanoparticle enhanced gene transfer could make it possible to use the systemic vasculature as the route of application and to magnetically trap these compounds at the target of interest. In this study we show that magnetic nanoparticle-coated microbubbles bind plasmid DNA and successfully deliver it to endothelial cells in vitro and more importantly transport their cargo through the vascular system and specifically deliver it to the vascular wall in vivo at sites where microbubbles are retained by magnetic force and burst by local ultrasound application. This resulted in a significant enhancement in site specific gene delivery compared with the conventional microbubble technique. Thus, this technology may have promising therapeutic potential.Graphical Abstract: Local vascular gene delivery in vivo by magnetic trapping of pDNA coated microbubbles. Magnetic microbubbles (MMB) coated with pDNA coding for dsRed were administered systemically (1) MMB were retained at the vessel wall in the dorsal skin fold chamber (left upper photo) by magnetic field application (2) and MMB were destroyed on ultrasound (3) 48-72 h after treatment dsRed expression was observed in the endothelium in the dorsal skin (4) but not in vessels of the cremaster muscle (right upper photo). The combination of magnetic targeting and ultrasound mediated MMB rupture resulted in high site specificity of gene delivery.

Nanoliposomal minocycline for ocular drug delivery - Corrected Proof

2012-03-29

Abstract: Nanoliposomal technology is a promising drug delivery system that could be employed to improve the pharmacokinetic properties of clearance and distribution in ocular drug delivery to the retina. We developed a nanoscale version of an anionic, cholesterol-fusing liposome that can encapsulate therapeutic levels of minocycline capable of drug delivery. We demonstrate that size extrusion followed by size-exclusion chromatography can form a stable 80-nm liposome that encapsulates minocycline at a concentration of 450 ± 30 μM, which is 2% to 3% of loading material. More importantly, these nontoxic nanoliposomes can then deliver 40% of encapsulated minocycline to the retina after a subconjunctival injection in the STZ model of diabetes. Efficacy of therapeutic drug delivery was assessed via transcriptomic and proteomic biomarker panels. For both the free minocycline and encapsulated minocycline treatments, proinflammatory markers of diabetes were downregulated at both the messenger RNA and protein levels, validating the utility of biomarker panels for the assessment of ocular drug delivery vehicles.Graphical Abstract: The leading cause of preventable blindness among working-age adults in the industrialized world is diabetic retinopathy (DR). Currently, there is no drug approved by the FDA specifically for DR, though various anti-inflammatory drugs are often used off-label, with limited success. Delivery of these pharmaceuticals to the retina poses a significant hurdle that inhibits the full therapeutic potential of many drugs. The figure presented here shows the promise of nanoscale liposomal subconjunctival delivery systems to cross the tissues of the eye and deliver therapeutic doses of an anti-inflammatory drug, minocycline, directly to the retina in a model of DR.

Dendrimers reduce toxicity of Aβ 1-28 peptide during aggregation and accelerate fibril formation - Corrected Proof

2012-03-29

Abstract: The influence of a GATG (gallic acid-triethylene glycol) dendrimer decorated with 27 terminal morpholine groups ([G3]-Mor) on the aggregation process of Alzheimer's peptide has been investigated. Amyloid fibrils were formed from the Aβ 1-28 peptide and the process was monitored by a ThT assay, changes in CD spectra, and transmission electron microscopy. In the presence of [G3]-Mor, more fibrils were built and the process significantly accelerated compared with a control. The cytotoxicity of (1) Aβ and (2) the system [G3]-Mor/Aβ was monitored at different stages of the aggregation process. Prefibrillar species were more toxic than mature fibrils. [G3]-Mor significantly reduced the toxicity of Aβ, probably because of lowering the amount of prefibrillar forms in the system by speeding up the process of fibril formation.Graphical Abstract: Dendrimer with terminal morpholine groups [G3]-Mor accelerates Aβ fibril formation.[G3]-Mor significantly reduces toxicity of Aβ 1-28.

Targeted cargo delivery using a rotating nickel nanowire - Corrected Proof

Li Zhang, Tristan Petit, Kathrin E. Peyer, Bradley J. Nelson — 2012-03-19

Abstract: This paper reports an approach to perform basic noncontact and contact manipulation tasks using rotating nickel nanowires driven by a rotating magnetic field. A rotating nanowire is capable of propulsion and steering near a solid surface by a tumbling motion. The FEM simulation shows that fluid flow is induced around the rotating nanowire, which was applied to manipulate micro-objects in a noncontact fashion. Pushing, pulling, and rotation tests of individual polystyrene microbeads are conducted on a solid surface. In addition, targeted delivery tasks of biological samples, e.g., individual flagellated microorganisms and human blood cells, are demonstrated. The results imply that rotating magnetic nanowires are good tools for handling cellular and subcellular objects in an aqueous low-Reynolds-number environment and have potential for single-cell analysis.Graphical Abstract: In this paper we present targeted delivery of individual microbeads, microorganism and blood cell in fluid using a rotating Ni nanowire. The Ni nanowires were navigated by a weak-strength rotating magnetic field with micrometer positioning precision.

Increased brain uptake of docetaxel and ketoconazole loaded folate-grafted solid lipid nanoparticles - Corrected Proof

2012-03-19

Abstract: Docetaxel is used in the treatment of many types of cancer, but its entry into the brain is restricted by p-glycoprotein (p-gp) efflux. A potential drug–drug interaction exists between docetaxel and ketoconazole because both agents are metabolized hepatically by the cytochrome P-450 system, and ketoconazole can inhibit p-gp efflux of docetaxel at blood brain barrier. Hence, these two drugs were loaded in solid lipid nanoparticles (SLNPs) and surface of these NPs were modified with folic acid for brain targeting. These NPs were characterized for particle size, zeta potential, entrapment efficiency, in vitro drug release, cytotoxicity, and cell uptake in brain endothelial cell lines. Plasma and brain pharmacokinetics have shown increased brain uptake of docetaxel with surface-modified dual drug-loaded SLNPs. Brain permeation coefficient (Kin) of folate-grafted docetaxel and ketoconazole loaded SLNPs was 44 times higher than that of Taxotere. Hence, these NPs were suitable for the delivery of lipophilic anticancer drugs to the brain.Graphical Abstract: Dual drug-loaded folate-grafted solid lipid nanoparticles (NPs) were prepared using solvent emulsification and evaporation method. Docetaxel and ketoconazole were selected as drugs to incorporate in solid lipid NPs because those drugs have potential drug–drug interaction. These NPs showed about 20-fold increased uptake in brain endothelial cells in comparison with Taxotere. Rhodamine 123 and ketoconazole-loaded solid lipid NPs were used for microscopic images. In vivo studies in Wistar rats also resulted in increased brain uptake of docetaxel and these NPs showed 44-fold increase in brain permeation coefficient (Kin) value in comparison with Taxotere.

NTS-Polyplex: a potential nanocarrier for neurotrophic therapy of Parkinson's disease - Corrected Proof

2012-03-09

Abstract: Nanomedicine has focused on targeted neurotrophic gene delivery to the brain as a strategy to stop and reverse neurodegeneration in Parkinson's disease. Because of improved transfection ability, synthetic nanocarriers have become candidates for neurotrophic therapy. Neurotensin (NTS)-polyplex is a “Trojan horse” synthetic nanocarrier system that enters dopaminergic neurons through NTS receptor internalization to deliver a genetic cargo. The success of preclinical studies with different neurotrophic genes supports the possibility of using NTS-polyplex in nanomedicine. In this review, we describe the mechanism of NTS-polyplex transfection. We discuss the concept that an effective neurotrophic therapy requires a simultaneous effect on the axon terminals and soma of the remaining dopaminergic neurons. We also discuss the future of this strategy for the treatment of Parkinson's disease.Graphical Abstract: pEF-Bos-hGDNF transfection in the substantia nigra promotes survival in the nigral dopaminergic neurons and reinnervation of the striatum in hemiparkinsonian rats. The figures were reproduced from Gonzalez-Barrios et al. with permission of Nature Publishing Group.

A new nano-cryosurgical modality for tumor treatment using biodegradable MgO nanoparticles - Corrected Proof

De-Rui Di, Zhi-Zhu He, Zi-Qiao Sun, Jing Liu — 2012-03-09

Abstract: A new conceptual modality for nano-cryosurgical ablation of tumors is proposed in this article. The main strategy is to apply MgO nanoparticles (NPs), which are nontoxic, biodegradable, and have few side-effects on the human body, to mediate the freezing procedure effectively. Detailed investigation via animal experiments and nucleation analysis demonstrated that delivery of MgO NPs into the target tissues would significantly improve the cryosurgical outcome. The formation of an iceball during the freezing process is accelerated and enlarged due to the excellent thermal properties of MgO NPs. In addition this method could promote the generation of ice nuclei and thus enhance cryoinjury to the target cells. Therefore, combining the biodegradability and nontoxicity of MgO NPs with their relatively lightweight properties, excellent thermal properties would help develop a high-performance cryosurgery. These findings may lead to methods for safe and targeted nano-cryosurgery and possibly break through the barriers facing current clinical treatments of cancer.Graphical Abstract: This article proposed a new conceptual modality for ablating tumors, the biodegradable MgO nanoparticles mediated cryosurgery. Experiments via infrared thermograph, histopathology section, differential scanning calorimetry, and nucleation theory all demonstrate that introduction of MgO nanoparticles into the target tissue significantly improves its freezing capability, which would lead to a highly promising “green” therapy on tumors.

Effects of nanoparticle surface-coupled peptides, functional endgroups, and charge on intracellular distribution and functionality of human primary reticuloendothelial cells - Corrected Proof

2012-03-09

Abstract: The medical use of nanoparticles (NPs) has to consider their interactions with the cells of the reticuloendothelial system. In this study the authors used gold nanorods coated by PEG chains bearing peptides or charged functional groups to study their influence on the uptake, subcellular distribution, and activation of human primary reticuloendothelial cells: monocytes, macrophages (MΦ), immature and mature dendritic cells (DC), and endothelial cells (EC). We found that beside MΦ and immature DC also EC internalize large quantities of NPs and observed an increased uptake of positively charged particles. Most notably, NPs accumulated in the MHC II compartment in mature DC that is involved in antigen processing. Furthermore, surface-coupled peptide sequences RGD and GLF altered the activation profile of DC, and modulated cytokine release in both DC and MΦ in a cell specific manner. These data suggest that the charge of NPs mainly influences their uptake, whereas conjugated peptides alter cell functions.Graphical Abstract: Light microscopical and transmission electron microscopical studies of mature dendritic cells and macrophages after incubation with positively charged gold nanoparticles.

Protein- and peptide-based electrospun nanofibers in medical biomaterials - Corrected Proof

Dhan B. Khadka, Donald T. Haynie — 2012-03-09

Abstract: Electrospun fibers are being studied and developed because they hold considerable promise for realizing some advantages of nanostructured materials. The fibers can be made of biocompatible and biodegradable polymers. Electrospinning has therefore attracted interest in biotechnology and medicine, and there has been rapid growth in this area in recent years. This review presents an introduction to polymer nanofiber electrospinning, focusing on the use of natural proteins and synthetic peptides. We summarize key physical properties of protein-based and peptide-based nanofiber mats, survey biomedical applications of these materials, identify key challenges, and outline future prospects for development of the technology for tissue engineering, drug delivery, wound healing, and biosensors.Graphical abstract: Protein and peptide electrospinning: apparatus, material properties, and biomedical applications.

Nitric oxide-releasing nanoparticles accelerate wound healing in NOD-SCID mice - Corrected Proof

2012-03-09

Abstract: Wound healing is a complex process, coordinated by various biological factors. In immunocompromised states wound healing can be interrupted as a result of decreased numbers of immune cells, impairing the production of effector molecules such as nitric oxide (NO). Therefore, topical NO-releasing platforms, such as diethylenetriamine (DETA NONOate), have been investigated to enhance wound healing. Recently, we demonstrated a nanoparticle platform that releases NO (NO-NPs) in a sustained manner, accelerating wound healing in both uninfected and infected murine wound models. Here, NO-NPs were investigated and compared to DETA NONOate in an immunocompromised wound model using non-obese, diabetic, severe combined immunodeficiency mice. NO-NP treatment accelerated wound closure as compared to controls and DETA NONOate treatment. In addition, histological assessment revealed that wounds treated with NO-NPs had less inflammation, more collagen deposition, and more blood vessel formation as compared to other groups, consistent with our previous data in immunocompetent animals. These data suggest that NO-NPs may serve as a novel wound-healing therapy in the setting of immunocompromised states associated with impaired wound healing.Graphical Abstract: Every other day dosing of a novel nitric oxide (NO) releasing nanoparticle platform applied to a splinted 5 mm punch biopsy full thickness wound in NOD-SCID mice resulted in accelerated wound closure as compared to controls, and as shown here, to comparable doses of a well known NO donor, DETA NONOate.

Nanoparticle-based adjuvant for enhanced protective efficacy of DNA vaccine Ag85A-ESAT-6-IL-21 against Mycobacterium tuberculosis infection - Corrected Proof

2012-03-09

Abstract: The goal of this study was to evaluate the protective efficacy of a cationic nanoparticle-based DNA vaccine expressing antigen 85A (Ag85A) and 6-kDa early secretory antigen target (ESAT-6) of Mycobacterium tuberculosis as well as cytokine interleukin-21 (IL-21) against M. tuberculosis infection. The results of this indicated that the anti–M. tuberculosis immune responses were induced in mice that had received the different DNA vaccines. More importantly, compared with using DNA vaccine Ag85A-ESAT-6-IL-21 alone, the nanoparticle-based DNA vaccine Ag85A-ESAT-6-IL-21 showed a statistically significant increase in the protective efficacy against M. tuberculosis infection in the immunized mice. We concluded that the nanoparticle-based DNA vaccine induced a strong immune response and markedly inhibited the growth of the M. tuberculosis in the mice. These findings highlighted the potential utility of Fe3O4-Glu-polyethyleneimine nanoparticles encapsulated with the DNA vaccine as a prophylactic vaccine in the M. tuberculosis–infected mouse model.Graphical Abstract: In this study, we developed the nanoparticle-based DNA vaccine Ag85A-ESAT-6-IL-21, which effectively transported DNA vaccine into cells. The IL-21 acted as an immunoadjuvant, the Ag85A-ESAT-6 fusion protein acted as target antigens, and the nano-Fe3O4-Glu nanoparticles served as the vaccine delivery system, inducing a powerful immune response and protection against M. tuberculosis challenge in a mouse model, compared with the DNA vaccine Ag85A-ESAT-6-IL-21 alone. Our findings show that the nanoparticle-based DNA vaccine Ag85A-ESAT-6-IL-21 enhances immune prophylactic efficacy to protect against M. tuberculosis infection.

Tracking T-cells in vivo with a new nano-sized MRI contrast agent - Corrected Proof

2012-03-09

Abstract: Non-invasive in vivo tracking of T-cells by magnetic resonance imaging (MRI) can lead to a better understanding of many pathophysiological situations, including AIDS, cancer, diabetes, graft rejection. However, an efficient MRI contrast agent and a reliable technique to track non-phagocytic T-cells are needed. We report a novel superparamagnetic nano-sized iron-oxide particle, IOPC-NH2 series particles, coated with polyethylene glycol (PEG), with high transverse relaxivity (250 s−1 mM−1), thus useful for MRI studies. IOPC-NH2 particles are the first reported magnetic particles that can label rat and human T-cells with over 90% efficiency, without using transfection agents, HIV-1 transactivator peptide, or electroporation. IOPC-NH2 particles do not cause any measurable effects on T-cell properties. Infiltration of IOPC-NH2−labeled T-cells can be detected in a rat model of heart-lung transplantation by in vivo MRI. IOPC-NH2 is potentially valuable contrast agents for labeling a variety of cells for basic and clinical cellular MRI studies, e.g., cellular therapy.Graphical abstract: Tracking T-cells in vivo with a new nano-sized MRI contrast agent.

In vivo particle tracking and photothermal ablation using plasmon-resonant gold nanostars - Corrected Proof

2012-02-27

Abstract: Gold nanostars offer unique plasmon properties that efficiently transduce photon energy into heat for photothermal therapy. Nanostars, with their small core size and multiple long thin branches, exhibit high absorption cross-sections that are tunable in the near-infrared region with relatively low scattering effect, making them efficient photothermal transducers. Here, we demonstrate particle tracking and photothermal ablation both in vitro and in vivo. Using SKBR3 breast cancer cells incubated with bare nanostars, we observed photothermal ablation within 5 minutes of irradiation (980-nm continuous-wave laser, 15 W/cm2). On a mouse injected systemically with PEGylated nanostars for 2 days, extravasation of nanostars was observed and localized photothermal ablation was demonstrated on a dorsal window chamber within 10 minutes of irradiation (785-nm continuous-wave laser, 1.1 W/cm2). These preliminary results of plasmon-enhanced localized hyperthermia are encouraging and have illustrated the potential of gold nanostars as efficient photothermal agents in cancer therapy.Graphical Abstract: The particle tracking and photothermal ablation in vivo upon laser irradiation through a dorsal window chamber on a mouse preinfused systemically with PEGylated gold nanostars, examined grossly and under multiphoton microscopy. After the irradiation, blood oozing and tissue damage developed, validating the efficacy of nanostars in photothermal therapy.

Delivery success rate of engineered nanoparticles in the presence of the protein corona: a systems-level screening - Corrected Proof

Daniele Dell'Orco, Martin Lundqvist, Tommy Cedervall, Sara Linse — 2012-02-27

Abstract: Nanoparticles (NPs) for medical applications are often introduced into the body via intravenous injections, leading to the formation of a protein corona on their surface due to the interaction with blood plasma proteins. Depending on its composition and time evolution, the corona will modify the biological behavior of the particle. For successful delivery and targeting, it is therefore important to assess on a quantitative basis how and to what extent the presence of the corona perturbs the specific interaction of a designed NP with its cellular target. We present a theoretical systems-level analysis, in which peptides have been covalently coupled to the surface of nanoparticles, describing the delivery success rate in varying conditions, with regard to protein composition of the surrounding fluid. Dynamic modeling and parameter sensitivity analysis proved to be useful and computationally affordable tools to aid in the design of NPs with increased success rate probability in a biological context.Graphical Abstract: A mathematical model is presented, which predicts the success rate of delivering an engineered nanoparticle (NP) to a biological target in the presence of the competing protein corona.

Ultradeformable archaeosomes as new topical adjuvants - Corrected Proof

2012-02-27

Abstract: Ultradeformable archaeosomes (UDA) are vesicles made of soybean phosphatidylcholine (SPC), sodium cholate (NaChol) and polar lipids from Halorubrum tebenquichense (3:1:3 wt/wt). Although ultradeformable liposomes (UDL, made of SPC and NaChol at 6:1 wt/wt) and UDA were neither captured nor caused cytotoxicity on keratinocytes, UDA was avidly captured by macrophages, their viability being reduced by 0.4-1.6 mg/ml phospholipids by 25 to 60%. Instead, UDL were poorly captured and caused no toxicity. Balb/C mice immunized by the topical route with four doses of ovalbumin (OVA)-loaded UDA, at 75 μg OVA/600 μg phospholipids (125 nm mean size and -42 mV zeta potential), induced IgG titers tenfold to 100-fold higher than those immunized with OVA-loaded UDL at the same dosage. Both matrices penetrate to the same skin depth (nearly 10 μm after 1 hour on excised human skin), being the higher topical adjuvancy and higher phagocytic uptake of UDA related to its glycolipid content.Graphical Abstract: A. Comparative skin penetration of OVA-UDA with that of OVA-UDL, OVA-L, and OVA-ARC. In spite of penetrating to comparable depth, OVA-UDA was more efficiently taken up by skin APC than OVA-UDL, and this could be related to their capacity to induce higher anti-OVA IgG serum titers. The non-ultradeformable OVA-L and OVA-ARC did not trigger systemic titers by topical route probably because of their impaired skin penetration.B. Serum IgG titers after topical OVA-UDA, in comparison with topical OVA-UDL, OVA-L, OVA-ARC, subcutaneous OVA-UDA, and intramuscular alum-adsorbed OVA.

Stability of antibody-conjugated gold nanoparticles in the endolysosomal nanoenvironment: implications for noninvasive radiofrequency-based cancer therapy - Corrected Proof

2012-02-20

Abstract: The use of noninvasive radiofrequency (RF) electric fields as an energy source for thermal activation of nanoparticles within cancer cells could be a valuable addition to the emerging field of nano-mediated cancer therapies. Based on investigations of cell death through hyperthermia, and offering the ability for total-body penetration by RF fields, this technique is thought to complement and possibly outperform existing nano-heat treatments that utilize alternative heat production via optical or magnetic stimuli. However, it remains a challenge to understand fully the complex RF-nanoparticle-intracellular interactions before full system optimization can be engineered. Herein we have shown that liver cancer cells can selectively internalize antibody-conjugated gold nanoparticles (AuNPs) through receptor-mediated endocytosis, with the nanoparticles predominantly accumulating and aggregating within cytoplasmic endolysosomes. After exposure to an external RF field, nonaggregated AuNPs absorbed and dissipated energy as heat, causing thermal damage to the targeted cancer cells. We also observed that RF absorption and heat dissipation is dependent on solubility of AuNPs in the colloid, which is pH dependent. Furthermore, by modulating endolysosomal pH it is possible to prevent intracellular AuNP aggregation and enhance thermal cytotoxicity in hepatocellular cancer cells.Graphical Abstract: Liver cancer cells can selectively internalize antibody-conjugated gold nanoparticles (C225-AuNPs) through receptor-mediated endocytosis, with the nanoparticles predominantly accumulating and aggregating within cytoplasmic endolysosomes. After exposure to an external radiofrequency (RF) field, nonaggregated AuNPs absorbed and dissipated energy as heat, causing thermal damage to the targeted cancer cells. We also observed that RF absorption and heat dissipation is dependent on solubility of AuNPs in the colloid, which is pH dependent. Furthermore, by modulating endolysosomal pH it is possible to prevent intracellular AuNP aggregation and enhance thermal cytotoxicity in hepatocellular cancer cells.

Novel thermogelling dispersions of polymer nanoparticles for controlled protein release - Corrected Proof

2012-02-20

Abstract: A novel poly(oligo(ethylene glycol) methyl ether methacrylate-co-oligo(ethylene glycol) ethyl ether methacrylate)–poly(acrylic acid) interpenetrating network (IPN) nanoparticle was synthesized. The temperature-responsive properties of the IPN nanoparticles were investigated by a dynamic light scattering method. Atomic force microscopic images confirmed the homogenous and monodisperse morphology of the IPN nanoparticles. Both visual observation and viscosity testing demonstrated that the IPN nanoparticles exhibit thermogelling properties at body temperature, 37°C. Subsequent studies verified that such temperature-sensitive properties of IPN nanoparticles allow their ease of injection and then slow release of model proteins, both in vitro and in vivo. Histological analysis showed that our IPN implants exerted minimal inflammation following subcutaneous implantation. Our results support the idea that, by simply mixing with proteins of interest, the novel IPN nanoparticles can be used to form in situ thermogelling devices for controlled protein release.Graphical Abstract: This article illustrates the preparation and characterization of injectable and thermogelling dispersions of nanoparticles composed of two interpenetrating networks of poly(oligo(ethylene glycol) methyl ether methacrylate-co-oligo(ethylene glycol) ethyl ether methacrylate)/ poly(acrylic acid) nanoparticles and its use for controlled protein release both in vitro and in vivo.

Enhanced delivery of gold nanoparticles with therapeutic potential into the brain using MRI-guided focused ultrasound - Corrected Proof

2012-02-20

Abstract: The blood brain barrier (BBB) is a major impediment to the delivery of therapeutics into the central nervous system (CNS). Gold nanoparticles (AuNPs) have been successfully employed in multiple potential therapeutic and diagnostic applications outside the CNS. However, AuNPs have very limited biodistribution within the CNS following intravenous administration. Magnetic resonance imaging guided focused ultrasound (MRgFUS) is a novel technique that can transiently increase BBB permeability allowing delivery of therapeutics into the CNS. MRgFUS has not been previously employed for delivery of AuNPs into the CNS. This work represents the first demonstration of focal enhanced delivery of AuNPs into the CNS using MRgFUS in a rat model both safely and effectively. Histologic visualization and analytical quantification of AuNPs within the brain parenchyma suggest BBB transgression. These results suggest a role for MRgFUS in the delivery of AuNPs with therapeutic potential into the CNS for targeting neurological diseases.Graphical Abstract: Magnetic resonance-guided focused ultrasound (MRgFUS) is a novel technique that can transiently increase BBB permeability allowing delivery of therapeutics into the brain. The feasibility of both focal and enhanced delivery of gold nanoparticles (AuNPs) with therapeutic potential was assessed and successfully demonstrated in this study.

N-trimethyl chitosan nanoparticle-encapsulated lactosyl-norcantharidin for liver cancer therapy with high targeting efficacy - Corrected Proof

2012-02-10

Abstract: N-Trimethyl chitosan (TMC) was synthesized and used to prepare lactosyl-norcantharidin TMC nanoparticles (Lac-NCTD-TMC-NPs) using an ionic cross-linkage process. Lac-NCTD-TMC-NPs with an average particle size of 120.6 ± 1.7 nm were obtained, with an entrapment efficiency of 69.29% ± 0.76%, and a drug-loading amount of 9.1% ± 0.07%. The release of Lac-NCTD-TMC-NPs in vitro was investigated through a dialysis method, and its sustained effect was evident. In the human liver cancer cell line HepG2, the half-maximum inhibiting concentration (IC50) of TMC-encapsulated Lac-NCTD (Lac-NCTD-TMC-NPs) was only 24.2% that of free Lac-NCTD at 24 hours. Lac-NCTD induced HepG2 cell death by triggering apoptosis. In vitro cellular uptake and in vivo NIR fluorescence real-time imaging both indicated a high targeting efficacy. In comparison with Lac-NCTD and Lac-NCTD chitosan NPs (Lac-NCTD-CS-NPs ), Lac-NCTD-TMC-NPs had the strongest antitumor activity on the murine hepatocarcinoma 22 subcutaneous model.Graphical Abstract: A novel nanoparticle (Lactosyl-norcantharidin trimethyl chitosan nanoparticles) that integrates active targeting of Lactosyl-norcantharidin by ligand binding onto the asialoglycoprotein receptor, charge targeting of N-trimethyl chitosan, and passive targeting function of nanoparticles was investigated in this study. The in vitro cellular uptake and in vivo NIR fluorescence real-time imaging both confirm the targeting characteristics.

Influence of sirolimus-loaded nanoparticles on physiological functions of native human polymorphonuclear neutrophils - Corrected Proof

Sandra Moeller, Ricarda Kegler, Katrin Sternberg, Ralf G. Mundkowski — 2012-02-10

Abstract: Sirolimus (SRL) is an immunosuppressive agent of high clinical relevance that has been associated with serious side effects. Biodegradable, SRL-loaded poly(d,l-lactide) nanoparticles (SRL-PLA-NPs) are being investigated as a drug delivery system to improve drug targeting. Polymorphonuclear neutrophils (PMNs) are phagocytes for particulate xenobiotics and also important trigger cells of the primary immune response. Therefore, the effects of SRL, SRL-PLA-NPs, and plain PLA-NPs on the viability of human PMNs, their essential functions, and the secretion of relevant cytokines were determined and evaluated with respect to the intracellular concentrations assessed by liquid chromatography–mass spectrometry ultra-trace analysis. For the first time to our knowledge, incorporation of NPs into PMNs was monitored by flow cytometry using fluorescence-labeled NPs. SRL accumulated intracellularly, exceeding therapeutic blood levels by a factor of two to four. Phagocytic activity was promptly reduced but recovered within 3 hours. No other parameters of the PMNs were affected. Hence, PLA-NPs appear suitable as drug carriers for SRL, allowing for better control of drug release.Graphical Abstract: Poly(d,l-lactide) nanoparticles are here shown to be suitable as drug carriers for the immunosuppressant sirolimus, offering the potential of better control over drug release. Deeper insight into the phagocytosis of these nanoparticles by polymorphonuclear neutrophils reveals interesting new details about the ingestion and elimination processes, as well as the pharmacodynamic or toxicodynamic implications for the functionality of these important trigger cells.

A novel therapeutic system for malignant glioma: nanoformulation, pharmacokinetic, and anticancer properties of cell-nano-drug delivery - Corrected Proof

Youhua Tao, Miaomiao Ning, Huanyu Dou — 2012-02-02

Abstract: Macrophage carriage, release, and antitumor activities of polymeric nanoformulated paclitaxel (PTX) were developed as a novel delivery system for malignant glioma. To achieve this goal, the authors synthesized PTX-loaded nanoformulations (nano-PTX), then investigated their uptake, release, and toxicological properties. Chemosensitivity was significant in U87 cells (P < 0.05) at concentrations from 10-4 to 10-8 M following 72 hours' exposure to bone-marrow-derived macrophages (BMM)-nano-PTX in comparison with treatment with nano-PTX alone. The most significant reductions in U87 cell viability (P < 0.05) were observed in the transwell cocultures containing BMM-nano-PTX. Limited toxicity to BMM was observed at the same concentrations. BMM functions were tested by analysis of microtubules and actin filaments, as the cytoarchitecture, demonstrating a similar cytoskeleton pattern before and after nano-PTX was loaded into cells. This data indicate that nanoformulations of PTX facilitate cell uptake, delay toxicity, and show improved therapeutic efficacy by BMM-nano-PTX delivery.Graphical Abstract: A novel anti-tumor drug nanoparticle (NP) was formulated for developing of cell-NP delivery system. NP are carried within bone-marrow-derived monocytes/macrophages (BMM) demonstrating extraordinary abilities to migrate across the BBB, infiltrate into tumor, and release the anti-tumor medicine.

Peptide PHSCNK as an integrin α5β1 antagonist targets stealth liposomes to integrin-overexpressing melanoma - Corrected Proof

2012-02-02

Abstract: As an integrin α5β1 antagonist, N-acetyl-proline-histidine-serine-cysteine-asparagine-amide (Ac-PHSCN-NH2) is currently in phase II trials for various cancer therapies. In this study Ac-PHSCNK-NH2 (PHSCNK) was used as a novel homing peptide to prepare ligand-targeted liposomes loaded with doxorubicin (PHSCNK-PL-DOX), with the hypothesis that the therapy target of integrin α5β1 may also serve as a delivery target. The stealth liposomes loaded with doxorubicin (PL-DOX) were used as the control. PHSCNK-PL-DOX demonstrated an enhanced intracellular uptake and a greater cytotoxicity against melanoma B16F10 cells in comparison with PL-DOX. The novel targeted formulation displayed stronger tumor inhibition and prolonged survival time in comparison with controls in C57BL/6 mice bearing B16F10 tumors, and it exhibited less heart toxicity in hematoxylin-eosin (H&E) staining of tissues. Taking the pharmacokinetics and biodistribution results into account, the authors conclude that α5β1 integrin-mediated liposomes might be used as a potential delivery system for targeted tumor therapy.Graphical Abstract: As an integrin α5β1 antagonist, N-acetyl-proline-histidine-serine-cysteine-asparagine-amide (Ac-PHSCN-NH2) is currently in phase II trials for various cancer therapies. In the present work, Ac-PHSCNK-NH2 (PHSCNK) was used as a novel homing peptide to prepare ligand-targeted liposomes loaded with doxorubicin (PHSCNK-PL-DOX), with the hypothesis that the therapy target of integrin α5β1 may also be served as a delivery target. The stealth liposomes loaded with doxorubicin (PL-DOX) were used as the control. PHSCNK-PL-DOX demonstrated an enhanced intracellular uptake and a greater cytotoxicity against melanoma B16F10 cells compared with PL-DOX. The novel targeted formulation displayed stronger tumor inhibition and prolonged survival time compared with controls in C57BL/6 mice bearing B16F10 tumor, while it exhibited less heart toxicity in H&E staining of tissues. Taking the pharmacokinetics and biodistribution results into account, it is concluded that α5β1 integrin-mediated liposomes might be used as a potential delivery system for targeted tumor therapy.

Mouse respiratory cilia with the asymmetric axonemal structure on sparsely distributed ciliary cells can generate overall directional flow - Corrected Proof

2012-02-02

Abstract: Mucociliary clearance on the surface of the tracheal lumen is an important component of lung defense against dust mites and viruses. However, the axonemal structure that achieves effective ciliary motion, and the mechanisms by which discretely distributed ciliary cells generate directional flow are unknown. In this study, we examined individual ciliary motion with 7- to 9-nm spatial precision by labeling the ciliary tip with quantum dots and detected an asymmetric beating pattern. Cryo-electron tomography revealed that the densities of two inner dynein arms were missing from at least 2 doublet microtubules in the axonemal structure. Although the flow directions generated by individual ciliated cells were unsteady and diverse, the time- and space-averaged velocity field was found to be directional. These results indicate that the asymmetric ciliary motion is driven by the asymmetric axonemal structure, and it generates overall directional flow from the lungs to the oropharynx on sparsely distributed ciliated cells.Graphical Abstract: The fluid flow with effective ciliary motion on the surface of the tracheal lumen is an important part of lung defense against dust mites, viruses, or other harmful substances. In this article, the authors examined the axonemal structure by cryo-electron tomography. The densities of two inner dynein arm subspecies were missing from at least two doublet microtubules, indicating that the asymmetric axonemal structure contributes to asymmetric ciliary motion, generates overall directional flow from the lungs to the oropharynx in airway.

Quantitative molecular profiling of biomarkers for pancreatic cancer with functionalized quantum dots - Corrected Proof

2012-02-02

Abstract: Applications in nanomedicine, such as diagnostics and targeted therapeutics, rely on the detection and targeting of membrane biomarkers. In this article we demonstrate absolute quantitative profiling, spatial mapping, and multiplexing of cancer biomarkers using functionalized quantum dots (QDs). We demonstrate highly selective targeting molecular markers for pancreatic cancer with extremely low levels of nonspecific binding. We confirm that we have saturated all biomarkers on the cell surface, and, in conjunction with control experiments, extract absolute quantitative values for the biomarker density in terms of the number of molecules per square micron on the cell surface. We show that we can obtain quantitative spatial information of biomarker distribution on a single cell, important because tumors' cell populations are inherently heterogeneous. We validate our quantitative measurements (number of molecules per square micron) using flow cytometry and demonstrate multiplexed quantitative profiling using color-coded QDs.Graphical Abstract: Quantitative targeting of pancreatic cancer biomarkers is demonstrated using quantum dot - antibody conjugates. Profiling and spatial mapping at the single cell level can be are achieved through minimizing non-specific binding and aggregation.

Gene delivery nanoparticles specific for human microvasculature and macrovasculature - Corrected Proof

Ron B. Shmueli, Joel C. Sunshine, Zhenhua Xu, Elia J. Duh, Jordan J. Green — 2012-02-02

Abstract: Endothelial cell dysfunction is a critical component of ocular diseases such as age-related macular degeneration and diabetic retinopathy. An important limitation in endothelial cell research is the difficulty in achieving efficient transfection of these cells. A new polymer library was here synthesized and utilized to find polymeric nanoparticles that can transfect macrovascular (human umbilical vein, HUVECs) and microvascular (human retinal, HRECs) endothelial cells. Nanoparticles were synthesized that can achieve transfection efficiency of up to 85% for HRECs and 65% for HUVECs. These nanoparticle systems enable high levels of expression while avoiding problems associated with viral gene delivery. The polymeric nanoparticles also show cell-specific behavior, with a high correlation between microvascular and macrovascular transfection (R2 = 0.81) but low correlation between retinal endothelial and retinal epithelial transfection (R2 = 0.21). These polymeric nanoparticles can be used in vitro as experimental tools and potentially in vivo to target and treat vascular-specific diseases.Graphical abstract: A class of polymers, poly(beta-amino esters), (PBAEs) was evaluated to find polymers that can transfect both microvascular (HREC) and macrovascular (HUVEC) cells. These polymers self-assemble with DNA to form nanoparticles (right). Certain PBAEs were able to transfect both of these types of cells with high efficiency (left), better than the leading commercially available reagents. Additionally, there is a strong correlation between the transfection profiles of these endothelial type cells (R2 = 0.81). This contrasts with a much lower correlation between the transfection profiles of the human retinal endothelial cells and human retinal pigment epithelial cells (R2 = 0.21).

Disassembly and reassembly improves morphology and thermal stability of human papillomavirus type 16 virus-like particles - Corrected Proof

2012-02-02

Abstract: Recombinant human papillomavirus (HPV) 16 L1 protein self-assembles into virus-like particles (VLPs) with diameters of 40 to 60 nm, which are key components in prophylactic HPV vaccines. Marked improvement in morphology and thermal stability on VLP disassembly and reassembly was demonstrated at production scale. Differential scanning calorimetry showed enhanced conformational stability as indicated by the unfolding temperatures and peak heights/areas. Cloud point studies indicated (1) a much lower propensity for post-reassembly VLPs to aggregate during a time course study and (2) much higher cloud point temperatures. In-solution atomic force microscopy showed more uniform size distribution and fully closed particles, with evidence of virion-like assembly revealed by the structural details from a single particle image. Similar approaches for the reassembly of other recombinant VLPs with intrinsic conformational switches would be expected to improve the particle properties and render nanoparticles more suitable for use as vaccines or therapeutics.Graphical Abstract: In-solution AFM characterization of HPV VLP size distribution, morphology and surface features.

Gold nanoparticles: the importance of physiological principles to devise strategies for targeted drug delivery - Corrected Proof

Madhusudhan R. Papasani, Guankui Wang, Rodney A. Hill — 2012-02-02

Abstract: Nanotechnology and its promise for clinical translation to targeted drug delivery with limited accompanying toxicity provide exciting research opportunities that demand multidisciplinary approaches. To make rapid progress in the design of nano-platforms for drug delivery and toward their use in the clinic, basic and mechanistic studies must first be tested in vitro and then progress to in vivo studies in animal models, incorporating an understanding of body functioning. Recently, gold nanoparticles (AuNPs) have gained much attention as model drug delivery platforms because of their advantageous surface characteristics that allow easy functionalization with chemical and biological molecules and also due to their apparently low toxicity. In this study we review recent in vitro and in vivo research progress with AuNPs as drug delivery platforms and suggest experimental strategies for future studies for efficacious, targeted delivery.

pH-Dependent nanostructure based on isoquinoline-cyclodextrin conjugate for thrombosis therapy - Corrected Proof

2012-01-16

Abstract: The modification of 3S-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (THIQA) with β-cyclodextrin (β-CD) provides an oral antithrombotic agent, 6-(3′S-isoquinoline-3′-carboxylaminoethylamino)-6-deoxy-β-CD (THIQA-β-CD). In aqueous solution THIQA-β-CD undergoes intermolecular inclusion complexation and forms pH-dependent nanostructures. The morphological feature of THIQA-β-CD is a nanocloud consisting of numerous particles that are 5 nm–6 nm in diameter at pH 3.0. The nanocloud switches to a nanorod ranging from 100 nm to 385 nm in length at pH 7.2, then to nanowires of 50 nm to 530 nm in length at pH 10.1. THIQA-β-CD, which has unusual nanostructures, offers enhanced stability in blood. Inhibition of thrombin-induced platelet aggregation in vitro and demonstrated antithrombotic efficacy in vivo. This investigation demonstrated that the modification of THIQA with β-CD is a promising approach for clinical therapy of thrombus disease. The pH-dependent nanostructures of conjugate provide the desired in vivo antithrombotic activity and in vitro stability in blood.Graphical Abstract: The modification of 3S-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (THIQA) with β-cyclodextrin (β-CD) provides an oral anti-thrombotic agent, THIQA-β-CD. In aqueous solution THIQA-β-CD undergoes self-assembly and forms pH-dependent nanostructures via intermolecular inclusion complexation. THIQA-β-CD with unusual nanostructures offers enhanced stability in blood, inhibition of thrombin induced platelet aggregation in vitro and high in vivo anti-thrombotic efficacy.

Improving interstitial transport of macromolecules through reduction in cell volume fraction in tumor tissues - Corrected Proof

Sarah McGuire, Fan Yuan — 2012-01-16

Abstract: Interstitial transport of large molecules and nanoparticles is an important concern in nanomedicine-mediated cancer treatment. To that end, the current study was proposed to improve the transport through enlargement of extracellular space by treating tumors with hypertonic solution of mannitol and cytotoxic agents (e.g., ethacrynic acid [ECA]), which could effectively shrink and kill cells, respectively. In the study, the improvement in interstitial penetration of dextran was investigated ex vivo using rat fibrosarcoma tissues sectioned into 600 μm slices. Experimental data showed that the hypertonic solution was more effective than ECA for improving interstitial penetration of dextran with molecular weights ranging from 4000 to 2,000,000. The extent of improvement depended on the size of dextran molecules and the time when the treatment was applied. Results from the study suggested that increases in both size and connectedness of interstitial pathways were important for improvement of interstitial transport of large molecules and nanoparticles.Graphical Abstract: Interstitial transport of macromolecules and nanoparticles in tumors can be improved through enlargement of extracellular space. In this study, the enlargement was achieved by treating tumor tissues with hypertonic solution of mannitol or a cytotoxic agent that could effectively shrink and kill cells. The treatments increased both the uniformity of distributions and the total amount of macromolecules diffused into tumor tissues.

Electrostatic assembly of a DNA superparamagnetic nano-tool for simultaneous intracellular delivery and in situ monitoring - Corrected Proof

Frédéric Geinguenaud, Inès Souissi, Remi Fagard, Laurence Motte, Yoann Lalatonne — 2012-01-16

Abstract: A superparamagnetic γFe2O3 nanocarrier was developed, characterized by spectroscopic methods and evaluated for the delivery of a decoy oligonucleotide (dODN) in human colon carcinoma SW 480 cells. This nanoparticle-dODN bioconjugate (γFe2O3@dODN) was designed to target the signal transducer and activator of transcription 3, STAT3, a key regulator of cell survival and proliferation. We exploited a simple precipitation-redispersion mechanism for the direct and one-step complexation of a labeled decoy oligonucleotide with iron oxide nanoparticles (NPs). The cell internalization of the decoy γFe2O3@dODN nanoparticles is demonstrated and suggests the potential for DNA delivery in biological applications. Despite the increasing use of NPs in biology and medicine, convenient methods to quantify them within cells are still lacking. In this work, taking advantage of the nonlinear magnetic behavior of our superparamagnetic NPs, we have developed a new method to quantify in situ their internalization by cells.Graphical Abstract: A superparamagnetic gFe2O3 nanocarrier was developed combining a delivery system of an oligonucleotide and a magnetic nanoprobe for in-situ monitoring. Such dual nanosystem was designed for targeting the signal transducer and activator of transcription 3, STAT3, a key regulator of cell survival and proliferation.

Harnessing nanoparticles to improve toxicity after head and neck radiation - Corrected Proof

2012-01-16

Abstract: This article reports the evaluation of cerium oxide (CeO2) nanoparticles' ability to decrease xerostomia and radiation-induced dermatitis in mice after head and neck radiation. Mice were irradiated using an IC160 x-ray system. Two cohorts were included: (A) No-radiation and (B) 30 Gy/6 fractions, and were randomized into three groups: (1) saline, (2) 15 nM CeO2 and (3) 15 μM CeO2. Stimulated salivary flow and radiation-induced dermatitis were evaluated post radiation. Stimulated sialometry demonstrated improved salivary production in all CeO2 groups in comparison with controls (flow: 204 vs. 115 μL/10 minutes, P = 0.0002). One week post radiation, G-III dermatitis decreased in the 15 μM group in comparison with controls (10% versus 100% incidence, respectively). There was decreased skin hyperpigmentation at 12 weeks in the 15-μM group in comparison with 15-nM and non-CeO2 groups (50%, 70%, and 90% G-II, respectively). This study suggests that CeO2 may be radioprotective for salivary production and reduces G-III dermatitis and skin hyperpigmentation incidence. CeO2 as radioprotectant may be a feasible concept during radiotherapy.Graphical Abstract: Radiation effects in the absence and presence of CeO2. Figure A: Sialometry 6 weeks after radiation suggests a dose-dependent decrease in salivary function. Figure B: Effects of CeO2 on salivary protection after radiation exposure. Results demonstrate a difference in saliva production between radiation-only controls and mice receiving radiation plus CeO2. Figure C: Effects of nanoceria on skin hyperpigmentation. Mice treated with 15 nM CeO2 nanoparticles (NPs) demonstrated a lower incidence of Grade II (33.33%) and a higher incidence of Grade I (66.67%) hyperpigmentation. Mice treated with 15 µM CeO2 NPs had an equal incidence of Grade I and II hyperpigmentation.

Preclinical evaluation of a pulmonary delivered paclitaxel-loaded lipid nanocarrier antitumor effect - Corrected Proof

Mafalda Videira, António J. Almeida, Àngels Fabra — 2011-12-29

Abstract: Lung cancer remains a leading cause of death due to the low efficacy of chemotherapy, mainly related to the administration route used. Therefore, alternative administration routes are needed. Paclitaxel (PTX) is an insoluble anticancer drug active against solid tumors, such as those found in lung cancer, that has stimulated an intense research effort over recent years. Solid lipid nanoparticles (SLNs) are potential carriers for poorly soluble drugs, being biodegradable systems that served as alternatives to the usual colloidal carriers. That system was used to deliver PTX to the lungs and seem to fulfill the requirements for an optimum particulate carrier. Furthermore, PTX-loaded SLN pulmonary administration provided a target administration, which is expected to avoid high concentration of the drug at nontarget tissues, reducing toxicity, and increasing the drug's therapeutic index. The rationale of this study was to deliver a colloidal system to the lung lymphatics through a pulmonary route for cancer therapy.Graphical Abstract: Lung cancer remains a leading cause of death due to low efficacy of chemotherapy, which is mainly related to the administration route used. Solid lipid nanoparticles (SLNPs) are potential carriers for poorly soluble drugs, being alternative biodegradable systems to the usual colloidal carriers. This system was used to deliver paclitaxel (PTX) to the lungs and seem to fulfil the requirements for an optimum particulate carrier. Furthermore, PTX-loaded SLNP pulmonary administration provided a target administration, which is expected to avoid high concentration of the drug at nontarget tissues, reducing toxicity and increasing the drug's therapeutic index. The rationale of this study was to deliver a colloidal system to the lung lymphatics through a pulmonary route for cancer therapy.

Albumin coupled lipid nanoemulsions of diclofenac for targeted delivery to inflammation - Corrected Proof

Prabhakar Kandadi, Muzammil Afzal Syed, Surendar Goparaboina, Kishan Veerabrahma — 2011-12-28

Abstract: Diclofenac lipid nanoemulsions (DLNEs) were prepared with different compositions. Based on size, PDI, zeta potential, and in vitro drug release, the optimized DLNEs (DLNE-4 and DLNE-7) were developed and evaluated for drug content, entrapment efficiencies, and stability in comparison to the control formulation (DLNE-1). The albumin was coupled to DLNE-7 globules (DLNE-8) by water soluble carbodiimide (EDC) method, purified, and quantified by modified Bradford method. The pharmacokinetic study was conducted in inflammation (granuloma air pouch model) induced rats. The maximum peak concentration of DLNE-8 was almost fourfold to fivefold in comparison to drug solution in granuloma air pouch fluid (GAPF). The therapeutic availability (TA) of DLNE-8 was 2.89, 2.34, and 1.66 times that of drug solution, DLNE-4 and DLNE-7, respectively. The GAPF/serum ratio of diclofenac from DLNE-8 was above one at all time points indicating the targeting potential of albumin ligated LNEs to inflammatory sites.Graphical Abstract: Diclofenac lipid nanoemulsions (DLNEs) were prepared with different compositions. Optimized formulations were developed based on size, PDI, zeta potential, and in vitro drug release. The optimized DLNEs were evaluated for drug content and entrapment efficiencies and stability. The albumin was coupled to DLNE-7 globules by EDC method and quantified by modified Bradford method. Granuloma air pouch was developed in rats to study in vivo pharmacokinetics. The rate and extent of absorption of diclofenac from albumin coupled LNE (DLNE-8) in granuloma air pouch fluid was higher than that of all other formulations indicating the preferential accumulation of drug at inflammatory site.

Nanostructured silver vanadate as a promising antibacterial additive to water-based paints - Corrected Proof

2011-12-26

Abstract: In this article, we report the use of nanostructured silver vanadate as a promising antibacterial additive to water-based paints that has potential for applications in bathrooms, kitchens, and hospital environments. This hybrid nanomaterial was prepared by a simple and fast precipitation reaction involving silver nitrate and ammonium vanadate, dismissing the hydrothermal treatment. The preparation involved using Ag vanadate nanowires (β-AgVO3) with diameters ranging from 20 to 60 nm and decorated with silver (Ag) nanoparticles (NPs) with diameters ranging from 5 to 40 nm. Results of antibacterial tests show that this hybrid material has a promising antibacterial activity against several types of bacteria strains, such as methicillin-resistant Staphylococcus aureas (MRSA), Enterococcus faecalis, Escherichia coli, and Salmonella enterica Typhimurium. The evaluated material exhibits antibacterial activity 30 times larger than that of Oxacillin. In addition, this nanomaterial was tested as an antibacterial additive to water-based paints, and formulations with 1% show a 4-mm inhibition zone against a MRSA strain.Graphical Abstract: Nanostructured silver vanadate is a promising antibacterial additive to water-based paints that is potential for applications in bathrooms, kitchens and hospitals environments thus certainly contributing to decrease the number of hospital infections

Mono-dispersed high magnetic resonance sensitive magnetite nanocluster probe for detection of nascent tumors by magnetic resonance molecular imaging - Corrected Proof

Chunfu Zhang, Xuan Xie, Sheng Liang, Mingli Li, Yajie Liu, Hongchen Gu — 2011-12-26

Abstract: Sensitive molecular imaging and detection of tumors or their supporting neovascularity require high-avidity, target-specific probes, which produce robust signal amplification compatible with a sensitive high-resolution imaging modality. In this context, we fabricated a high magnetic resonance (MR)-sensitive magnetite nanocluster (MNC) probe specific for tumor angiogenesis by assembly of hydrophobic superparamagnetic iron oxide nanoparticles (SPIONs) with (Mal)mPEG-PLA copolymer into cluster and subsequent encoding c(RGDyC) peptide on the cluster (RGD-MNC) for detection of nascent tumors. We found that RGD-MNC is highly sensitive (r2 = 464.94 s-1mM-1) and specific for αvβ3-positive cells. Both nascent (35 ± 6.6 mm3) and large tumors (256 ± 22.3 mm3) can be registered by RGD-MNC and detected by MR imaging (MRI), with the nascent tumors demonstrating more pronounced MR contrast. Immunohistochemical studies revealed that MR signal decrease was closely correlated with histological characteristics of tumors (microvessel density and αvβ3 expression levels) at different growth stages.Graphical Abstract: Due to its high sensitivity and specificity, both nascent and big tumors can be detected by RGD-MNC, and the MRI contrast is highly correlated with angiogenic vessel densities and αvβ3 integrin expression levels of tumors at different growth stages.

Polystyrene nanoparticles affecting blood coagulation - Corrected Proof

Cecilia Oslakovic, Tommy Cedervall, Sara Linse, Björn Dahlbäck — 2011-12-26

Abstract: The association of nanoparticles (NPs) with blood coagulation proteins may influence the natural balance between pro- and anticoagulant pathways. We investigated whether polystyrene NPs, when added to human plasma, affected the generation of thrombin in plasma. Amine-modified NPs were found to decrease the thrombin formation due to binding of factors VII and IX to the NPs, which resulted in depletion of the respective protein in solution. In contrast, carboxyl-modified NPs were able to act as a surface for activation of the intrinsic pathway of blood coagulation in plasma. These results highlight the influence of NPs on a biologically important pathway.Graphical Abstract: This article explores schematic picture of the different effects on blood coagulation by polystyrene nanoparticles (NPs). Blood coagulation can be activated either through the intrinsic/contact pathway or through the extrinsic pathway. Amine-modified NPs bind FVII and FIX, which leads to a decrease in thrombin formation. Carboxyl-modified NPs are able to activate the intrinsic pathway of coagulation by activation of FXII.

Quantitative characterization of the lipid encapsulation of quantum dots for biomedical applications - Corrected Proof

2011-12-26

Abstract: The water solubilization of nanoparticles is key for many applications in biomedicine. Despite the importance of surface functionalization, progress has been largely empirical and very few systematic studies have been performed. Here we report on the water solubilization of quantum dots using lipid encapsulation. We systematically evaluate the monodispersity, zeta potential, stability, and quantum yield for quantum dots encapsulated with single and double acyl–chain lipids, pegylated double acyl–chain lipids, and single alkyl–chain surfactant molecules with charged head groups. We show that charged surfactants and pegylated lipids are important to obtain monodisperse suspensions with high yield and excellent long-term stability.Graphical Abstract: Lipid encapsulation is a biomimetic approach to water solubilization of nanoparticles that takes advantage of hydrophobic interactions to drive formation of an outer leaflet. The physicochemical properties of lipid-encapsulated nanoparticles, such as monodispersity, zeta potential, stability, and quantum yield, can be optimized by varying the composition of the lipid layer through combinations of single- and double–acyl chain lipids, pegylated double–acyl chain lipids, and single–alkyl chain surfactant molecules with charged head groups.

ERα signaling imparts chemotherapeutic selectivity to selenium nanoparticles in breast cancer - Corrected Proof

Kiritkumar K. Vekariya, Jasmine Kaur, Kulbhushan Tikoo — 2011-12-26

Abstract: The present study focuses on the synthesis of stable selenium nanoparticles (SeNPs) and the elucidation of their mechanism of action in preventing the growth of mammary tumors. Selenious acid and reduced glutathione in the presence of sodium alginate were used as precursors for synthesis of SeNPs. Cell viability and expression of apoptotic markers (pp38, Bax, and cytochrome c) were assessed in MCF-7 and MDA-MB-231 breast cancer cells treated with SeNPs. Reduction in tumor volume was measured in rats with dimethylbenz[a]anthracene-induced mammary tumors. Synthesized SeNPs ranged in size from 40 to 90 nm and were stable up to 3 months of storage. We report that SeNP-induced cell death and expression of pp38, Bax, and cytochrome c were significantly higher in estrogen receptor-α (ERα)–positive cells (MCF-7) but not in ERα-negative cells (MDA-MB-231). Interestingly, animals showing significant decrease in tumor volume (small tumors) had lower levels of ERα as compared with animals showing a nonsignificant decrease in tumor volume (large tumor). This is the first report in our knowledge suggesting that the anticancer activity of SeNPs correlates with the level of ERα in breast cancer cells both in vivo and in vitro.Graphical Abstract: MCF-7 cells, which are rich in ERα receptors are more susceptible to apoptosis when treated with SeNPs as compared with SeNPs–treated MDA-MB-231 cells, which do not have many ERα receptors. Thus, we propose a causal relationship between the levels of ERα and SeNPs–mediated cell death.

Characterization of high-affinity peptides and their feasibility for use in nanotherapeutics targeting leukemia stem cells - Corrected Proof

2011-12-26

Abstract: Peptides featuring the LR(S/T) motif were identified that could specifically bind to the C-type lectin-like molecule-1 (CLL1), a protein preferentially expressed on acute myeloid leukemia stem cells (LSCs). Micellar nanoparticles were covalently decorated with CLL1-targeting peptides for targeted drug delivery. The resulting peptide-coated nanoparticles were 13.5 nm in diameter and could be loaded with 5 mg of daunorubicin per 20 mg of telodendrimers. These “targeting nanomicelles” transported the drug load to the interior of cells expressing CLL1 and to LSCs isolated from clinical specimens in vitro, but did not bind to normal blood or normal hematopoietic stem cells. The presence of CLL1-targeting peptides on the surface of the nanomicelles enabled the improved binding and delivery of substantially more daunorubicin into the cells expressing CLL1 and CD34+ leukemic cells compared with unmodified nanomicelles. In conclusion, nanomicelles coated with CLL1-targeting peptides are potentially useful for eradicating LSCs and improving leukemia therapy.Graphical Abstract: A chemotherapeutic drug, drug combinations and/or radioisotopes are loaded inside nanomicelles. Targeting ligands against leukemia stem cell (LSC) surface molecules are decorated on the surface of nanomicelles. After intravenous administration, these targeting nanomicelles can specifically deliver high-concentration therapeutic agents to and eradicate LSC. In addition, the therapeutic agents can diffuse into blood circulation to kill leukemic cells throughout the body. Furthermore, formulation of chemotherapeutic drugs in nanomicelles can decrease therapy-related toxicity and improve treatment outcomes.

Improving intraperitoneal chemotherapeutic effect and preventing postsurgical adhesions simultaneously with biodegradable micelles - Corrected Proof

2011-12-07

Abstract: The two major concerns after cytoreductive surgery of abdominal and pelvic malignancies are residual tumors and peritoneal adhesions, which are inevitable and have great impact on prognosis. Therefore, to improve the intraperitoneal chemotherapeutic effect and prevent postsurgical adhesions simultaneously after surgery, we developed a novel strategy that combines the controlled drug delivery system (CDDS) with an antiadhesion barrier. Biodegradable poly(ethylene glycol)–poly(ɛ-caprolactone)–poly(ethylene glycol) (PECE) copolymer formed micelles in water, which turned instantly into a nonflowing gel at body temperature as a result of micellar aggregation. Effectiveness of doxorubicin-loaded PECE micelles (Dox-M) in improving intraperitoneal chemotherapeutic effect and preventing adhesions was investigated. Subsequently, we established a novel mouse model for postsurgical residual tumors and peritoneal adhesions, in which Dox-M could improve intraperitoneal chemotherapeutic effect and prevent postsurgical peritoneal adhesions simultaneously. Thus, it is a promising strategy to combine the CDDS and barrier method to improve the intraperitoneal chemotherapeutic effect and prevent peritoneal adhesions simultaneously after surgery.Graphical Abstract: A novel strategy to improve the effect of postsurgical intraperitoneal chemotherapy and prevent peritoneal adhesions simultaneously after cytoreductive surgery is proposed in this work, which combines a controlled drug delivery system with a barrier method. Our results indicated that the drug-loaded micelles showed an impressive antitumor and adhesion prevention effect in a novel mouse model of postsurgical residual tumors and peritoneal adhesion.

Release profile and transscleral permeation of triamcinolone acetonide loaded nanostructured lipid carriers (TA-NLC): in vitro and ex vivo studies - Corrected Proof

2011-11-23

Abstract: Nanostructured lipid carriers (NLC) have been developed for sustained release of triamcinolone acetonide (TA), a corticosteroid commonly indicated for macular edema, neovascularization, and other ocular inflammatory disorders. TA-NLC were prepared by high-pressure homogenization and characterized for in vitro release by dialysis bag. Ex vivo permeation profile was assessed using rabbit sclera isolated and mounted in Franz diffusion cells. TA-NLC were placed in episcleral donor compartment and choroidal side was perfused with HEPES buffer. Tissue sections underwent drug wash-out, following analysis by validated RP-HPLC of drug content and perfused fractions collected over 24 hours. Drug release followed one-order kinetics and permeability studies confirmed that TA is able to diffuse across rabbit sclera in sustained profile, following zero-order kinetics. Strong tissue binding was observed, providing a drug depot. These findings are of potential use when designing future TA therapy strategies for ocular diseases of posterior segment.Graphical Abstract: Nanostructured Lipid Carriers (NLC) have been developed for sustained release of Triamcinolone Acetonide (TA), a corticosteroid commonly indicated for macular oedema, neovascularization and other ocular inflammatory conditions. Drug release from NLC followed one-order kinetics. Ex vivo permeability studies confirmed that TA is able to diffuse through rabbit sclera in a sustained profile, following a zero-order kinetic model. Strong tissue binding was observed, providing a drug depot.

An investigation on the antibacterial, cytotoxic, and antibiofilm efficacy of starch-stabilized silver nanoparticles - Corrected Proof

2011-11-23

Abstract: The increased emergence of drug resistant microbes creates a major challenge to the scientific community for successful development of effective therapeutics. The antimicrobial activities of silver ions are well known, but limited information is available on the effects of green silver-nanoparticles (AgNPs) on human pathogens. In this article, we evaluated the antibacterial activity of starch-stabilized AgNPs against a panel of human pathogens commonly associated with air, water and food borne infections. The shape and size distribution of AgNPs were characterized by transmission electron microscopy. We showed that AgNPs were more effective against Gram-positive and Gram-negative pathogens as compared with acid-fast bacteria. AgNPs were not cytotoxic to macrophages at the bactericidal concentration and can augment intracellular killing potential of macrophages. Furthermore, we showed that AgNPs disrupt biofilm formation and exhibit better antibacterial activity compared to human cationic antimicrobial peptide LL-37. In summary, our data suggest AgNPs as a promising template for the design of novel antibacterial agents.Graphical abstract: Graphical representation of different activities of AgNPs against bacteria and macrophages. Starch-stabilized AgNPs exhibit antimicrobial activity, inhibit biofilm formation, no cytotoxic effect on mouse macrophages, and kill intracellular bacteria.

In vitro mechanistic study of cell death and in vivo performance evaluation of RGD grafted PEGylated docetaxel liposomes in breast cancer - Corrected Proof

Sachin Naik, Deepa Patel, Krishna Chuttani, Anil K. Mishra, Ambikanandan Misra — 2011-11-23

Abstract: Objectives of the investigations were to prepare RGD grafted docetaxel liposomes (RGD-PEG-LP-DC) using supercritical fluid technology and evaluate it in vitro for cytotoxicity, DNA content analysis, mechanism of cell death, and in vivo for pharmacokinetic and biodistribution studies in BALB/c mice. The RGD-PEG-LP-DCs were found to be most cytotoxic in BT-20 and MDA-MB-231 cell lines. The flowcytometry results shows at 48 hours, 96% G2 phase arrest for RGD-PEG-LP-DC at 5 nM drug concentration. The mode of cell death was found to be mainly by necrosis at low drug equivalent concentration (1 nM) and by apoptosis at high drug equivalent concentration (10 nM). With increase in time and concentration the mode of cell death by apoptosis was found to be increasing. Biodistribution demonstrated that site specific drug distribution, t1/2, and MRT improved significantly for RGD-PEG-LP-DC. From the studies site specific and sustained intracellular drug delivery from RGD-PEG-LP-DCs may provide promising strategy in enhancing embattled against breast cancer treatment.Graphical Abstract: