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Melittin is a potential anticancer candidate with remarkable antitumor activity and ability to overcome tumor drug resistance. However, the clinical applications of melittin are largely restricted by its severe hemolytic activity and nonspecific cytotoxicity after systemic administration. Here, a biocompatible and stable melittin-loaded lipid-coated polymeric nanoparticle (MpG@LPN) formulation that contains a melittin/poly-γ-glutamic acid nanoparticle inner core, a lipid membrane middle layer, and a polyethylene glycol (PEG) and PEG-targeting molecule outer shell was designed. The formulations were prepared by applying a self-assembly procedure based on intermolecular interactions, including electrostatic attraction and hydrophobic effect. The core-shell MpG@LPN presented high efficiency for melittin encapsulation and high stability in physiological conditions. Hemolysis and cell proliferation assays showed that the PEG-modified MpG@LPN had almost no hemolytic activity and nonspecific cytotoxicity even at high concentrations. The modification of targeting molecules on the MpG@LPNs allowed for the selective binding with target tumor cells and cytolytic activity via apoptosis induction. In vivo experiments revealed that MpG@LPNs can remarkably inhibit the growth of tumors without the occurrence of hemolysis and tissue toxicity. Results suggested that the developed MpG@LPN with a core-shell structure can effectively address the main obstacles of melittin in clinical applications and has great potential in cancer treatment.

Topical treatment of various skin disorders requires drug absorption and penetration through the stratum corneum (SC) into the epidermis and dermis tissues. The use of nano-drug delivery systems including liposomes and lipid nanoparticles (SLNs) have been shown to facilitate SC penetration. The goal of this work was to study the impact of liposome sizes and the resulted drug distribution inside various skin tissue. All trans retinoic acid (ATRA) was used as the model drug and loaded into gel phase HSPC/CHOL/DSPE-PEG liposomes (lipo-ATRA) with sizes ranging from 80 nm to more than 300 nm. The percutaneous drug absorption process was monitored and analyzed. There were significant differences in percutaneous absorption and tissue distribution resulted from liposomes smaller than 100 nm and those bigger than 200 nm. Lipo-ATRA with a mean diameter of 83 nm can deliver the content to epidermis and dermis. But for 200 nm - 300 nm liposomes, the resulted epidermis and dermis ATRA levels were less than about one third, suggesting bigger liposomes had poor penetration through the brick and mortar structure of SC. Gel phase liposomes with sizes under 100 nm improved encapsulated drug absorption and distribution into the epidermis and dermis tissues. A size dependent mechanism for liposome penetration of the stratum corneum was proposed.

The absorption of peptides and proteins delivered orally is minimum because of the intestine epithelial barrier. There are few known active transport mechanisms for macromolecules including the neonatal Fc Receptor (FcRn) for the absorption and secretion of IgGs in infant and adult intestine. We had previously described the FnAb-8 protein that could bind to hFcRn tightly at pH 6.0 but barely at pH 7.4. In this study, we examined its uptake, biodistribution and pharmacokinetics after peroral administration in both wild-type and human FcRn transgenic (Tg) mice. FnAb-8 was modified to contain trans-cyclooctene (TCO) which could interact with 18F labeled tetrazine in situ via the bioorthogonal inverse-electron-demand Diels−Alder reaction. We showed that FnAb-8 had a tendency to distribute and persist in the Tg mice intestine for an extended duration of time. It could also be absorbed into the circulation and distributed systemically over a long period of time up to 172 h. The improvement in oral uptake and concentration in the intestine tissue may be valuable for designing oral delivery of biopharmaceuticals, especially for diseases involving the gastric intestinal tissue., Graphical abstract PET/CT images of FcRn Tg mice after receiving p.o. administration of FnAb-8-TCO and in situ labeling by Tz-NOTA-Al18F injected intravenously.Image, graphical abstract

In this study, an excellent phosphate adsorbent was prepared for removing phosphate to an extremely low concentration. The La(OH)3 nano-rods stabilizing in polyacrylonitrile (PAN) nanofibers (PLNFs) were prepared by electrospinning and a subsequent in situ precipitation. PAN nanofibers were employed as the matrix of the composite nanofibers, where the well-dispersed La(OH)3 nano-rods were encapsulated as the active species for highly efficient phosphate capture owing to the strong binding between phosphate and lanthanum. On account of the nano-structure, the maximum phosphate adsorption capacity was 151.98 mg P/g (La), much higher than the result of La(OH)3 nano-crystal, produced by precipitation without PAN or any organic surfactants. Moreover, the PLNFs could remove phosphate (2 mg P/L) to an extremely low concentration within 20 min, which could lead to a nutrient deficient condition to protect water quality and ecosystem. The optimization of PLNFs design was implemented through parameter adjustment of electrospinning. Lanthanum salt content, humidity, concentration of solution and applied voltage were chosen to analyze the influences on the composition, diameter and morphology of the nanofibers, giving the result that the most effective adsorbent was the PLNFs with spider-web-like nano-structures.

Ursolic acid (UA) is a potent triterpenoid compound found in plants and fruits with activities modulating key cell signaling pathways involving STATs, NF-κB, and TRAIL. But it's highly hydrophobic and very poorly soluble in nature. It had been prepared as nanocrystals, solid dispersion and loaded in nanoparticles but the achieved systemic exposure and circulation half-life were not ideal. We reported the development of UA-liposomes made by HPβCD assisted active loading. Compared to lipid suspensions of UA (Lipid-UA) with similar lipid composition, the novel process enabled the formation of UA-Ca crystalline structures inside the liposomes and therefore sustained release of UA in vivo. While the UA-liposomes were not generally toxic towards 4T1 triple negative breast cancer cells, they could effectively modulate CD4+CD25+Foxp3+ T cells from 4T1 tumor bearing mouse by inhibiting STAT5 phosphorylation and IL-10 secretion. In vivo administration of UA-liposomes at 10 mg/kg dose led to reduced numbers of myeloid derived suppressor cells (MDSCs) and regulatory T cells (Tregs) residing in tumor tissues. These changes signified the correction of the tumor mediated immune-suppressive microenvironment. The UA-liposomes treatment alone was already effective in deterring tumor growth. Such a formulation may be highly promising as an immunotherapy agent and be combined with chemotherapeutics or targeted drugs.

Drug encapsulated liposomes and monoclonal antibodies (Mabs) are two distinctively different classes of therapeutics, but both aim to become the ultimate "magic bullet". While PEGylated liposomes rely on the enhanced permeability and retention (EPR) effect for accumulation in solid tumor tissues, Mabs are designed to bind tightly to specific surface antigens on target cells to exert effector functions. Immunoliposome (IL) refers to the structural combination of liposomes and antibodies, whereas the antibodies are usually decorated on the liposome surface. ILs can therefore take advantage of interactions between antibodies and cancer cells for more efficient endocytosis and intracellular drug delivery. The antibody structure, affinity, density, as well as the liposome surface properties and drug to lipid ratios all contribute to the IL pharmacokinetic(PK) and pharmacodynamic(PD) behaviors. The optimal formulation parameters may vary for different target cells and tissues. Furthermore, besides the delivery of cytotoxic drugs to cancer cells, new ILs are being developed to interact with multiple target receptors, multiple target cells and trigger multiple therapeutic effects. We envision that the IL format can be a great platform for the molecular engineering of multi-valent, multi-specific interactions to achieve complex biological functions for therapeutic benefits, especially in the area of cancer immunotherapy.

The structural, mechanical and thermodynamic properties of tungsten-based alloys, including W0.5Ti0.5,W0.67Zr0.33,W0.666Ti0.1667Zr0.1667,W0.67Hf0.33 and W0.666Ti0.1667Hf0.1667, have been investigated in this paper by first-principles calculations based on density functional theory (DFT). The calculated elastic constants and mechanical stability criteria of cubic crystals indicated that all of these cubic alloys are mechanical stable. The mechanical properties, including bulk modulus (B), shear modulus (G), Young’s modulus(E), ratio B/G, Poisson’s ratio, Cauchy pressure and Vickers hardness are derived from the elastic constants Cij. According to calculated elastic modulus and Vickers hardness, the W0.666Ti0.1667Hf0.1667 alloy has the greatest mechanical strength. The Vickers hardness of these cubic alloys rank as follows: W0.666Ti0.1667Hf0.1667 > W0.67Zr0.33 > W0.666Ti0.1667Zr0.1667 > W0.5Ti0.5 > W0.67Hf0.33. Moreover, calculated ratio B/G, Poisson’s ratio, Cauchy pressure indicated that the ductility of W0.666Ti0.1667Hf0.1667 alloy is the worst among these alloys. The ductility of these cubic alloys rank as follows: W0.67Hf0.33 > W0.5 Ti0.5 > W0.67Zr0.33 > W0.666Ti0.1667Zr0.1667 > W0.666Ti0.1667Hf0.1667. What is noteworthy is that both mechanical strength and ductility of W0.666Ti0.1667Hf0.1667 are greater than pure W. Finally, Debye temperature, melting point and thermal conductivity have been predicted through empirical formulas. All these results will provide scientific data for the study on new product development of electrode materials.

Nano-drug delivery systems are designed to contain surface ligands including antibodies for “active targeting”. The number of ligands on each nanoparticle, known as the valency, is considered a critical determinant of the “targeting” property. We sought to understand the correlation between valency and binding properties using antibody conjugated liposomes, i.e. immunoliposomes (ILs), as the model. Anti-CD3 Fab containing a terminal cysteine residue were conjugated to DSPE-PEG-maleimide and incubated with preformed liposomes at 60°C. The un-incorporated antibodies were removed and the obtained ILs were characterized to contain in average 2–22 copies of anti-CD3 Fabs per liposome. The Biolayer Interferometry (BLI) probe surface was coated with various densities of CD3 epsilon&delta heterodimer (CD3D/E) to imitate different CD3 expression levels on target cells. The inference wavelength shifts upon anti-CD3 liposome binding were monitored and analyzed. The data indicated ILs may bind either monovalently or multivalently, determined mainly by the surface ligand density rather than the ILs antibody valency. The ILs valency indeed correlated with the dissociation rate constant (Koff), but not with the association rate constant (Kon). Their binding capabilities also did not necessarily increase with the surface anti-CD3 valency. We proposed a model for understanding the binding properties of ILs with different ligand valencies. The binding mode may change when the targeted surfaces had different antigen densities. The model should be important for the designing and optimization of active targeting drug delivery systems to fit different applications.

Liposomes, as one of the most successful nanotherapeutics, have a major impact on many biomedical areas. In this study, we performed laser scanning confocal microscope (LSCM) and immunohistochemistry (IHC) assays to investigate the intra-tumor transport and antitumor mechanism of GE11 peptide-conjugated active targeting liposomes (GE11-TLs) in SMMC7721 xenograft model. According to classification of individual cell types in high resolution images, biodistribution of macrophages, tumor cells, cells with high epidermal growth factor receptor (EGFR) expression and interstitial matrix in tumor microenvironment, in addition, their impacts on intra-tumor penetration of GE11-TLs were estimated. Type I collagen fibers and macrophage flooded in the whole SMMC7721 tumor xenografts. Tumor angiogenesis was of great heterogeneity from the periphery to the center region. However, the receptor-binding site barriers were supposed to be the leading cause of poor penetration of GE11-TLs. We anticipate these images can give a deep reconsideration for rational design of target nanoparticles for overcoming biological barriers to drug delivery., Graphical abstract A reported EGFR-targeted peptide GE11 was employed to modify PEGylated liposomes. The distribution and extravasation of GE11-TLs in SMMC7721 HCC xenograft model are well investigated. EGFR positive interstitial cells in tumor microenvironment generate the dominant barrier for deeper permeation for GE11-TLs, though collagen I is the major abundant interstitial matrix in SMMC7721 tumor.Image 1

Bone cements have been used in the clinical setting to fill bone defects resulting from bone tumors. However, traditional bone cements do not have the function to kill tumor cells. This study develops a new type of tricalcium silicate (CS) based functional bone cement with excellent photothermal performance for the minimally invasive therapy of bone defects as well as bone tumors. Graphene oxide (GO) was introduced into the CS cement by co-precipitation of CS particles with GO nanosheets to form a CS/GO composite material based on charge interactions between the CS and GO. The incorporation of GO enhanced the self-setting properties of CS and endowed the cement with excellent photothermal performance with the irradiation of near-infrared light. Besides this, the temperature of the composite cement could be regulated by adjusting the laser power and the GO content, where the rising temperature significantly inhibited the growth of subcutaneous tumor tissue in vivo. In addition, the hydration process and development of the early compressive strength of the composite cement could be modulated based on its photothermal performance. Moreover, the CS/GO composite cement retained the bioactivity of CS to promote cell proliferation and the alkaline phosphate activity of MC3T3-E1. Therefore, the CS/GO composite cement holds great promise as a new type of functional bone cement with photothermal performance for bone tumor therapy and bone defect repair.

We developed an anticancer siRNA delivery system (named HLPR) through modular assembly of endogenous molecules. The structure of HLPR was a tightly condensed siRNA-peptide inner core in turn surrounded by the disordered lipid layer and thin HA coating from which the EGFR-targeted amino acid sequences of YHWYGYTPQNVI partially protrude outside of cell surfaces. Both HA and YHWYGYTPQNVI anchored on HLPR were responsible for targeting CD44 and EGFR overexpressed on the tumor cell surfaces, respectively. HLPR was relatively stable in the blood circulation and reached the tumor tissue in vivo through passive and active targeting. Then HLPR entered tumor cells mainly through EGFR-mediated pathway followed by the separation of HA from the remaining parts of nanocomplexes. The HA-uncoated complexes escaped the endosome through the membrane fusion function of DOPE and released cargoes (siRNA and peptide/siRNA) in the cytoplasm. HLPR significantly inhibited the growth of implanted subcutaneous liver tumors without toxicity.

Hyaluronan (HA) based biomaterials are widely used as tissue scaffolds, drug formulations, as well as targeting ligands and imaging probes for diagnosis and drug delivery. However, because of the presence of abundant endogenous HA presented in various tissues in vivo, the pharmacokinetic behavior and biodistribution patterns of exogenously administered HAs have not been well characterized. The HA backbone was modified with Diethylenetriamine (DTPA) to enable the chelation of gadolinium (Gd) and aluminum (Al) ions. Series of PET and MR imaging were taken after the injection of HA-DTPA-Gd and HA-DTPA-Al18F while using18F-FDG and Magnevist(DTPA-Gd) as controls. The Tomographic images were analyzed and quantified to reveal the distribution and locations of HA in tumor-bearing mice. The labeled HAs had good stability in plasma. They retained binding affinity towards CD44s on tumor cell surface. The injected HAs distributed widely in various organs, but were found to be cleared quickly except inside tumor tissues where the signals were higher and persisted longer. Medical imaging tools, including MR and PET, can be highly valuable for examining biomaterial distribution non-invasively. The HA tumor accumulation properties may be explored for the development of active targeting drug carriers and molecular probes.

Qianru Yu,1,* Maxin Zhang,1,* Yuetan Chen,1,* Xiaolong Chen,2 Sanyuan Shi,1 Kang Sun,1 Ran Ye,1 Yuan Zheng,1 Yang Chen,1 Yuhong Xu,1,3 Jinliang Peng1 1School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China; 2NanoDrug Platform, Zhejiang California International NanoSystems Institute, Zhejiang University, Hangzhou 310058, People’s Republic of China; 3School of Pharmacy and Chemistry, Dali University, Dali City 671000, People’s Republic of China *These authors contributed equally to this workCorrespondence: Jinliang PengSchool of Pharmacy, Shanghai Jiao Tong University, No. 800, Dongchuan Road, Shanghai 200240, People’s Republic of ChinaTel/Fax +86 21 3420 4739Email pjl76@sjtu.edu.cnBackground: The complex preparation procedures and severe toxicities are two major obstacles facing the wide use of chimeric antigen receptor-modified T (CAR-T) cells in clinical cancer immunotherapy. The nanotechnology-based T cell temporary CAR modification may be a potential approach to solve these problems and make the CAR-T cell-based tumor therapy feasible and broadly applicable.Methods: A series of plasmid DNA-loaded self-assembled nanoparticles (pDNA@SNPsx/y) prepared from adamantane-grafted polyamidoamine (Ad-PAMAM) dendrimers of different generations (G1 or G5) and cyclodextrin-grafted branched polyethylenimine (CD-PEI) of different molecular weights (800, 2000, or 25,000 Da) were characterized and evaluated. The detailed physicochemical properties, cellular interaction, and cytotoxicity of selected pDNA@SNPG1/800 were systematically investigated. Thereafter, the epidermal growth factor receptor variant III (EGFRvIII) CAR-expression plasmid vector (pEGFRvIII-CAR) was constructed and encapsulated into SNPG1/800. The resulting pEGFRvIII-CAR@SNPG1/800 was used for Jurkat cell transient transfection, and the EGFRvIII-CAR expressed in transfected cells was measured by flow cytometry and Western blot. Finally, the response of EGFRvIII CAR-positive Jurkat T cell to target tumor cell was evaluated.Results: The pDNA@SNPG1/800 showed the highest efficacy in Jurkat cell gene transfection and exhibited low cytotoxicity. pEGFRvIII-CAR@SNPG1/800 can efficiently deliver pEGFRvIII-CAR into Jurkat T cells, thereby resulting in transient EGFRvIII-CAR expression in transfected cells. EGFRvIII-CAR that is present on the cell membrane enabled Jurkat T cells to recognize and bind specifically with EGFRvIII-positive tumor cells.Conclusion: These results indicated that pEGFRvIII-CAR@SNPG1/800 can effectively achieve T-cell transient CAR modification, thereby demonstrating considerable potential in CAR-T cancer therapy.Keywords: self-assembled nanoparticle, PAMAM dendrimer, polyethylenimine, epidermal growth factor receptor variant III, chimeric antigen receptor, T lymphocyte

Cancer stem cells (CSC) that may account for only a small fraction of tumor mass were found to play crucial roles during tumor initiating, progression, and metastasis. However, they are usually difficult to be treated and notoriously resilient to drug eradication. In this study, we aimed at the Wnt signaling characteristic of CSCs and designed a liposomal drug delivery system to target CSCs. Liposomes decorated with RSPO1 on the surface were constructed for specific interactions with the Wnt pathway coreceptor LGR5. Doxorubicin carried by the RSPO1-liposomes was more effective at lower concentrations than the same drug loaded in PEG-liposomes. More importantly, we showed using a patient-derived xenograft tumor model where LGR5+ CSCs coexisted with LGR5− cells, the RSPO1-liposomes were able to access more CSC cells and deliver the drug specifically and efficiently. Such a focused effect in eradicating LGR5+ cells led to massive tumor tissue necrosis and growth inhibition even when only a fraction of the conventional drug dose was used. These data clearly demonstrated the advantages of CSC-targeted drug delivery and would support the development of such approaches as a new cancer treatment strategy. Mol Cancer Ther; 17(7); 1475–85. ©2018 AACR.

We rationally formulated a nucleic acid nanovector platform utilizing endogenous molecules in the following steps: nucleic acids are initially packed by a multifunctional peptide and a cationic liposome to form positively charged ternary complexes through electrostatic interaction; then the ternary complexes were coated with hyaluronic acid (HA) to form negatively charged quaternary nanocomplexes (Q-complexes). Among the components of Q-complexes, the multifunctional peptide was composed of a poly-16-arginine (R16) and a hepatic tumor-targeted cell penetrating peptide (KRPTMRFRYTWNPMK); the cationic lipid component included DOTAP and fusogenic lipid DOPE; the HA component shielded the cationic ternary complexes and actively targeted the CD44 overexpressed on the surface of tumor cells. Q-complexes have showed a relatively high stability in the medium, and HA component partially separated from the nanocomplexes after the Q-complexes bound to the cancer cells. The Q-complexes showed significantly enhanced n...

A direct metal-free method for the synthesis of perfluoroalkylated indolizines by means of DIPEA-promoted tandem C N/C C bond formation was developed. Various substituted pyridines and bromoacetyl derivatives with methyl perfluoroalk-2-ynoates proceeded smoothly in this mild transformation, and the desired products were obtained in good to excellent yields under air.

In this study, a boron-doped microporous carbon (BMC)/sulfur nanocomposite is synthesized and applied as a novel cathode material for advanced Li-S batteries. The cell with this cathode exhibits an ultrahigh cycling stability and rate capability. After activation, a capacity of 749.5 mAh/g was obtained on the 54th cycle at a discharge current of 3.2 A/g. After 500 cycles, capacity of 561.8 mAh/g remained (74.96% retention), with only a very small average capacity decay of 0.056%. The excellent reversibility and stability of the novel sulfur cathode can be attributed to the ability of the boron-doped microporous carbon host to both physically confine polysulfides and chemically bind these species on the host surface. Theoretical calculations confirm that boron-doped carbon is capable of significantly stronger interactions with the polysulfide species than undoped carbon, most likely as a result of the lower electronegativity of boron. We believe that this doping strategy can be extended to other metal-air batteries and fuel cells, and that it has promising potential for many different applications.

Luchen Zhang,1 Zhenbo Li,1 Fangli Sun,2 Yuhong Xu,1 Zixiu Du1 1School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 2School of Engineering, Zhejiang Agriculture and Forestry University, Lin’an, Zhejiang Province, People’s Republic of China Abstract: A safe and efficient quaternary gene delivery system (named Q-complexes) was constructed based on self-assembly of molecules through noncovalent bonds. This system was formulated through the cooperation and competing interactions of cationic liposomes, multifunctional peptides, and DNA, followed by coating hyaluronic acid on the surface of the ternary complexes. The multifunctional peptide was composed of two functional domains: penetrating hepatic tumor-targeted cell moiety (KRPTMRFRYTWNPMK) and a wrapping gene sequence (polyarginine 16). The effect of spacer insertion between the two domains of multifunctional peptide on the intracellular transfection of Q-complexes was further studied. Experimental results showed that the formulations assembled with various peptides in the spacer elements possessed different intercellular pathways and transfection efficiencies. The Q-complexes containing peptide in the absence of spacer element (Pa) showed the highest gene expression among all samples. The Q-complexes containing peptides with a noncleavable spacer GA (Pc) had no ability of intracellular nucleic acid delivery, whereas those with a cleavable spacer RVRR (Pd) showed moderate transfection activity. These results demonstrated that the different spacers inserted in the multifunctional peptide played an important role in in vitro DNA transfection efficiency. Atomic force microscopy images showed that the morphologies of ternary complexes (LPcD) and Q-complexes (HLcPD) were crystal lamellas, whereas those of other nanocomplexes were spheres. Circular dichroism showed the changed configuration of peptide with spacer GA in nanocomplexes compared with that of its free state, whereas the Pa configuration without spacer in nanocomplexes was consistent with that of its free state. The present study contributed to the structural understanding of Q-complexes, and further effective modification is in progress. Keywords: Q-complexes, spacer elements, multifunctional peptides, lipid component, intracellular transfection

Although RNA interference (RNAi) technology shows great potential in cancer treatment, the tumor target delivery and sufficient cytosolic transport of RNAi agents are still the main obstacles for its clinical applications. Herein, we report a functional supramolecular self-assembled nanoparticle vector for RNAi agent loading and tumor target therapy. Molecular block adamantane-grafted poly(ethylene glycol) (Ad-PEG) was modified with epidermal growth factor receptor (EGFR)-specific binding ligand GE11 or pH-sensitive fusogenic peptide GALA and then used for self-assembly with cyclodextrin-grafted branched polyethylenimine (CD-PEI), adamantane-grafted polyamidoamine dendrimer (Ad-PAMAM), and plasmid DNA containing a small hairpin RNA expression cassette against vascular endothelial growth factor (VEGF) into functional DNA-loaded supramolecular nanoparticles (GE11&GALA-pshVEGF@SNPs) based on molecular recognition and charge interaction. These functional peptides facilitated the target cell binding, internalization, and endosomal escape of GE11&GALA-pshVEGF@SNPs, resulting in increased reporter gene expression and efficient targeted gene silencing. The systemic delivery of the GE11&GALA-pshVEGF@SNPs can efficiently downregulate the intratumoral VEGF protein levels, reduce blood vessel formation, and significantly inhibit A549 xenograft tumor growth. These results reveal the potential of these multifunctional self-assembled nanoparticles as a nucleic acid drug delivery system for the treatment of lung cancer.

Many cancer cells express CD47 as a 'don't eat me' signal to mask their presences from immune recognition and destruction. Such a signal is transmitted when CD47 binds to the signal regulatory protein-α (SIRPα) on macrophages to cut the phagocytic reaction. Most recent studies have focused on developing CD47 blocking agents with different affinities and avidities in order to optimize the therapeutic window between efficacy and toxicities involving normal cells expressing CD47. We described in this study a new design to fuse one CD47 binding domain of SIRPα with a pharmacokinetics modifying domain F8. The resulted single valent long-acting CD47 antagonist SIRPα-F8 was able to bind to CD47 and disrupt CD47-SIRPα axis. However, by itself it cannot trigger endocytosis and has no effect on tumor growth. Only when used in combination with the anti-CD20 mAbs, there were greatly improved phagocytic activities towards CD20 positive cancer cells. In vivo the combination also resulted in better tumor growth inhibition comparing to the vehicle control group. In addition, we showed that the F8 fusion bound to hFcRn only inside endosomes at pH 6.0, enabled hFcRn mediated recycling and thus greatly extended the circulation half-life in hFcRn knock-in mice. Taken together, the SIRPα-F8 design may suggest a new option to improve the therapeutic index of antibody treatment in clinical use towards tumors.

In order to support the design and manufacture the cesium (Cs) oven for the prototype negative ion source in the Chinese Fusion Engineering Test Reactor-Negative Ion Based Neutral Beam Injection (CFETR-NNBI) system, an advanced cesium oven is being set up at IFS. The design scheme is proposed based on the characteristics of the prototype negative ion source in the CFETR-NNBI system and combined with the international frontier research related to this aspect. Based on the reference to the Padova cesium oven, this article has designed a dedicated nozzle for the cesium oven and a transport channel more conducive to steam transport. A corrosion-resistant Cs reservoir and delivery tube is utilized. Precise control of cesium flux is achieved via remotely controlled switching valves and heating systems. The surface ionization detector is used to detect the cesium flux of the nozzle. And the thermal stability analysis, thermal transient analysis, thermal stress analysis and thermal deformation analysis were carried out on the design. The feasibility of the design is demonstrated through finite element analysis, which provides a theoretical basis for the next step of manufacturing. The cesium flux of oven is simulated and calculated, which provides reference for the subsequent device testing.

Trivalent cerium (Ce(Ⅲ)) was demonstrated to have great potential for phosphate (P) removal. Besides the valence states, the relationship of nano-structure and adsorption capacity needs further study to explore more efficient adsorbents. Herein, a series of Ce(Ⅲ)-terephthalate (BDC) metal-organic framework (MOF) with linker deficiencies are fabricated to achieve excellent P capture. The defective density can be increased by decreasing the reaction time and the ratio of organic linkers/metal. TGA reveals Ce-BDC-48 synthesized with BDC:Ce ratio of 1:1 for 48 h possessed 2.5 missing linkers per inorganic node. And the P uptake of Ce-BDC-48 was 35% higher than that of Ce-BDC-72 without defects. The maximum adsorption capacity of Ce-BDC-48 was 278.8 mg/g for P and 128.0 mg/g for fluoride (F), respectively. The adsorption mechanism illustrates that both P and F mainly focus on the Ce(Ⅲ) active sites to achieve ligand exchange. The competing adsorption of P and F at the lower concentration of F (50 mg/L) indicates that the interference of F for P removal is insignificant on account of the selective preferential order of P. However, with the increment of F concentration (100 mg/L), amount of F with small sizes gathering around the adsorbent surface enlarge the steric hindrance to hinder the access of P, leading to the sharp decline of P uptake. This study not only provides promising candidate by the design of structural defects for the P removal in practical application but also give a deep analysis on the adsorption mechanism of P with competing F surrounded.

As sucrose esters (SEs) are natural and biodegradable excipients with excellent drug dissolution and drug absorption/permeation in controlled release systems, we firstly incorporated SE into liposomes for gene delivery in this article. A peptide-based lipid (CDO14), Gemini-based quaternary ammonium-based lipid (CTA14), and mono-head quaternary ammonium lipid (CPA14), and SE as helper lipid, were prepared into liposomes which could enhance the interactions between liposomes and pDNA. Most importantly, the liposomes with helper lipid SE showed higher transfection and lower cytotoxicity than those without SE in Hela and A549 cells. It was also found that the transfection efficiency increased with the increase of SE content. The selected liposome, CDO14/SE, was able to deliver siRNA against luciferase for silencing gene in lung tumors of mice, with little in vivo toxicity. The results convincingly demonstrated SEs could be highly desirable candidates for gene delivery systems.

The effects of particle size of microspheres on the drug release from a microsphere/sucrose acetate isobutyrate (SAIB) hybrid depot (m-SAIB) was investigated to develop a long-term sustained release drug delivery system with low burst release both in vitro and in vivo. A model drug, risperidone, was first encapsulated into PLGA microspheres with different particle sizes using conventional emulsification and membrane emulsification methods. The m-SAIB was prepared by dispersing the risperidone-microspheres in the SAIB depot. The drug release from m-SAIB was double controlled by the drug diffusion from the microspheres into SAIB matrix and the drug diffusion from the SAIB matrix into the medium. Large microspheres (18.95 ± 18.88 µm) prepared by the conventional homogenization method exhibited porous interior structure, which contributed to the increased drug diffusion rate from microspheres into SAIB matrix. Consequently, m-SAIB containing such microspheres showed rapid initial drug release (Cmax = 110.1 ±54.2 ng/ml) and subsequent slow drug release (Cs(4-54d)= 2.7 ± 0.8 ng/ml) in vivo. Small microspheres (5.91 ± 2.24 µm) showed dense interior structure with a decreased drug diffusion rate from microspheres into SAIB matrix. The initial drug release from the corresponding m-SAIB was significantly decreased (Cmax = 40.9 ± 13.7 ng/ml), whereas the drug release rate from 4 to 54 d was increased (Cs(4-54d)=4.1 ± 1.0 ng/ml). By further decreasing the size of microspheres to 3.38 ± 0.70 µm, the drug diffusion surface area was increased, which subsequently increased the drug release from the m-SAIB. These results demonstrate that drug release from the m-SAIB can be tailored by varying the size of microspheres to reduce the in vivo burst release of SAIB system alone.

The development of new therapeutic vaccines for the efficient induction of cellular immunity by antigen cross-presentation in antigen-presenting cells, especially dendritic cells, is regarded as a promising approach to prime antigen-specific T cell responses and to destroy tumor cells. We synthesized low molecular weight polyethylenimine (C12-PEI) with a modified hydrophobic lipid chain by the direct coupling of 1-bromododecane with low molecular weight polyethylenimine (MW 423 Da) in a 2 : 1 molar ratio. This was bound with model antigen ovalbumin (OVA) to form sphere-like polyplex nanoparticles (size 158–302 nm; zeta potential −18.4 to −13.1 mV) by electrostatic interaction at an C12-PEI/OVA weight ratio of 0.03–0.08. The in vitro cytotoxicity of the C12-PEI/OVA nanoparticles was strongly dependent on the weight ratio of the C12-PEI and OVA. The antigen cross-presentation effect (IL-2 secretion) of the C12-PEI/OVA polyplexes was also dependent on the weight ratio. Optimized cross-presentation was achieved on the C12-PEI/OVA-0.07/1 polyplexes, which was 5.3-fold higher than that of the free OVA solution and 1.9-fold higher than that of the PEI/OVA polyplexes. The intracellular distribution of the C12-PEI/rhodamine-labeled OVA polyplexes demonstrated the lysosome localization effect. These results indicated that the synthesized C12-PEI cationic polymer with a modified hydrophobic lipid chain could potentially be used as a therapeutic vaccine carrier for delivery of the OVA antigen.

The electronic structure and associated chemical characteristics of metal-based adsorbent are directly relevant to the selectivity and efficiency of phosphate uptake. However, few studies focus on the nature of metal centers’ electronic orbit (i.e., the coordination number and valence state). Herein, we report a coordinatively unsaturated Ce(III)-based materials, which exhibits excellent potential in effective phosphate removal. Via controlled partial thermolysis and the following reduction process, the valence state and coordination number of original Ce(III)-MOF (denoted as CM) can be tuned and optimized. The manufacture of more coordination vacancy was fulfilled through total release of solvent molecules under annealing at 300 °C in air. Meanwhile, the reduction procedure could precisely tuned the ratio of Ce(III)/Ce(IV). The result shows that samples only annealed induce a sharp decrease of the phosphate capacity due to the high amount of Ce(IV) state. After the reduction process, the XPS spectra reveal the growth of oxygen vacancy content calculated as 11.6% and the increase of Ce(III)/Ce(IV) values from 0.79:1 to 1.36:1. Based on those great improvement of the unsaturated coordination numbers and the recovery of Ce(III) content for metal centers, the maximum capacity of CM-300(R) to adsorb phosphate is up to 273 mg/g, 2.6 times larger than that of pristine CM. Those new insights provide a novel strategy for synthesizing a highly active adsorbent by controlling the electronic structure of metal centers for efficient phosphate removal.

e15644 Background: All-Trans-Retinoid-Acid (ATRA) is a naturally occurring vitamin A metabolite that participates in many biological processes. Beside its highly potent effect of promoting terminal differentiation of acute promyelocytic leukemia blasts into mature granulocytes, there have been many other studies suggesting its activity on the myeloid derived suppressor cells (MDSCs) and tumor specific CD8+ T cells in animal models as well as using clinical samples. But the use of ATRA as an immune-oncological agent in solid tumor therapy has been limited by the very poor solubility of the compound, its fast metabolism, and very limited exposure achieved after oral administration. Methods: We prepared a new dosage form by encapsulating ATRA inside PEGylated liposomes. The liposomes were shown to accumulate inside solid tumor tissues and deliver more ATRA with longer duration. Results: The effect and dose response of the liposomal ATRA on CT26 murine tumor growth were examined, as well as specific molecular signatures concerning tumor infiltrating myeloid cells. Notably, there was significant higher expression of CD86 and lower expression of PD-L1. These myeloid cells had very low inhibitory effect on ex vivo activated T cells, while on the other hand could promote specific antigen presentation to amplify CD8+ T cells. Furthermore, the liposomal ATRA was also shown to synergize with anti-PD-1 treatment to result in more CD8 T cell distribution in the tumor tissues. Conclusions: These data may suggest an exciting opportunity for targeting MDSCs using liposomal ATRA for combination with T cell based therapeutics in cancer immunotherapy.

A series of hierarchical micro/nano Ce-based composites were derived from Ce-MOF via thermal treatment in N2 atmosphere. Different from conventional complete decomposed materials, forming cerium oxide in air, Ce-MOF that calcinated in N2 at lower temperatures (400 °C or 500 °C) showed a partial thermal decomposition with high percent content of Ce(III). Even though the complete decomposed products held higher surface areas, the partial decomposed samples exhibited extremely higher phosphate uptake, with working capacity 2–4 times higher than that of ceria. The results implied a predominant effect of different valence states on phosphate removal by Ce-based materials, in which Ce(III) species were demonstrated playing the major role to form binding with phosphate. The maximum adsorption capacity (189.4 mg/g) was achieved by Ce-MOF-500(S) with wide applicable scope of pH ranging from 2 to 12 and great selectivity for phosphate in the presence of competing anions. Remarkably, Ce-MOF-500(S) described obvious enhanced phosphate adsorption ability under alkaline condition. This was due to the fact that the hydrolyzed Ce(III) species brought more active sites in the form of hydroxyl groups for ligand exchange with phosphate. Furthermore, based on the analysis of FTIR, XPS, XRD and zeta potential, electrostatic attraction, ligand exchange and surface precipitation were confirmed as the main adsorption mechanisms for partial decomposed samples, while electrostatic attraction was the main mechanism for complete decomposed samples.

We have constructed Herceptin-conjugated, paclitaxel (PTX) loaded, PCL-PEG worm-like nanocrystal micelles (PTX@PCL-PEG-Herceptin) for the combinatorial therapy of HER2-positive breast cancer that exploit the specific targeting of Herceptin to HER2-positive breast cancer cells. Firstly, amphiphilic PCL2000-MPEG2000 and PCL5000-PEG2000-CHO were selected as the optimized matrix to wrap PTX that self-assembled into worm-like micelles with internal nanocrystal structures (PTX@PCL-PEG). Then the aldehydes of PCL5000-PEG2000-CHO exposed on the outside surface of PTX@PCL-PEG were utilized to react with the primary amines of Herceptin and formed stable, carbon-nitrogen single linkers (–C–N–) between the antibodies and nanoparticles. This study shows PTX@PCL-PEG-Herceptin remained relatively stable in the circulation and in the tumor microenvironment, and rapidly targeted and entered into the HER2-overexpressing tumor cells while sparing normal tissues from the toxic effects. PTX@PCL-PEG-Herceptin shrank the tumors and prolonged survival time in a SKBR-3-tumor-xenograft, nude mice model more effectively than TAXOL®, PTX@PCL-PEG, Herceptin+TAXOL® and Herceptin+PTX@PCL-PEG. Mechanistic studies showed that PTX@PCL-PEG-Herceptin entered into the HER2-positive tumor cells through the caveolin-mediated pathway. The conjugated Herceptin greatly enhanced the binding ability of the nanoparticle to the targeted SKBR-3 cells. This novel strategy provides a rational and simple antibody-conjugated-nanoparticle platform for the clinical application of combinatorial anticancer treatment.

Synthetic oligodeoxynucleotides (ODN) containing unmethylated CpG motifs were found to be able to target cells that express Toll-like receptor 9 to modulate innate and adaptive immune reactions. But their in vivo application in immunotherapy against cancer has not been successful. We attempted in this study to examine polyethylene-glycol (PEG) conjugated CpG ODNs and investigated their mechanism of immune modulation in anti-cancer therapy. CpG-PEG conjugates with different PEG lengths were synthesized. In vitro activity as well as in vivo pharmacokinetics and pharmacodynamics properties were evaluated. CpG-PEG20Ks were found to be able to persist longer in circulation and activate various downstream effector cells. After intravenous injection, they resulted in higher levels of IL-12p70 in the circulation and lower M-MDSC infiltrates in the tumor microenvironment. Such activities were different from those of CpG ODNs without PEGylation, suggesting different PK-PD profiles systemically and locally. Our data support the development of CpG-PEGs as a new therapeutic agent that can be systemically administered to modulate immune responses and the microenvironment in tumor tissues.

A practical and economical process for the synthesis of perfluoroalkylated biphenyl derivatives has been developed. The three-component reaction of aromatic ketones, malononitrile and methyl perfluoroalk-2-ynoates gave the desired products in good to excellent yields via a one-pot two-step process.

Lithium–sulfur (Li–S) batteries with high theoretical capacities and low cost are a strong candidate for future energy storage, but their development is hindered by many shortcomings, such as high-rate capacity decay due to the “shuttle effect”. Herein, we increase the capacity retention and cycle life of the Li–S battery through the addition of an interlayer made of polypyrrole (PPy)-treated carbon paper (CP) in a Li–S battery. We first quantitatively investigate the effect of the thickness of the carbon paper and then optimize a novel interlayer prepared by using PPy adhered to the carbon paper. The results show that 300 μm CP is the best choice among the three thicknesses. The CP-300 samples deliver a reversible capacity of 490 mAh g−1 after 200 cycles with a 0.5 C rate and show the best rate performance. Because of the porous structure and conductivity of the as-prepared PPy interlayer, the battery incorporating the PPy interlayer exhibits more excellent cycle performance and better rate performance than the CP batteries. Surprisingly, the PPy-coated CP-200 battery displays a reversible capacity of 555 mAh g−1 after 200 cycles with a 0.5 C rate. This feasible way to modify a carbon paper interlayer may have promising prospects in the Li–S battery field.

A folic acid (FA) conjugated chitosan oligosaccharide (CSO) polylactic acid (PLA) copolymer FA-CSO-PLA with double disulphide linkage in the backbone directed by H-bonding association duplex was synthesized, and its self-assembled micelles were evaluated as smart targeted drug delivery carriers. Both of the intermediates and the terminal copolymers were characterized by 1H-NMR and gel permeation chromatography (GPC). The critical micelle concentration (CMC) value is 0.045 mg mL−1 which suggests the micelles are highly stable in dilute solution. TEM and DLS further confirmed the successful formation of micelles with an average size of 61 and 100 nm, PDI of 0.209 and 0.230 for blank and DOX loaded micelles, respectively. The micelles were destructed under a reductive environment, leading to encapsulated drug release. Moreover, fluorescence microscopy demonstrated that the micelles exhibited both a passive and active targeting ability in HeLA cells due to an EPR effect and folate-mediated endocytosis. These results suggested the micelles would provide a favourable platform for constructing excellent drug delivery systems for cancer therapy.

Instructed by association units that allow reversible and unsymmetrical disulfide bond formation, hydrophilic (PEG) and hydrophobic (PLA) polymer chains are efficiently coupled into amphiphilic diblock copolymers. The desymmetrization of otherwise symmetrical reversible disulfide bond formation is achieved with amide association units that integrate both directional H-bonding and reversible disulfide bond formation, which ensure the connection of different polymer blocks while minimizing self-coupling. The resultant amphiphilic block copolymers self-assemble into long-lasting spherical micelles that are responsive to free thiols.

The creation of a moist environment and promotion of blood vessel formation are critical for wound healing. Sodium alginate (SA) hydrogel, which has good biocompatibility and is able to provide a moist environment, has been widely used as a wound dressing. However, it lacks antibacterial ability and bioactivities, which would facilitate chronic wound healing. On the basis of the gelation characteristics of SA and the bioactive hardystonite (HS) bioceramic, we designed a unique, bioactive, injectable composite hydrogel through double ion cross-linking, in which divalent ions, such as Ca2+ and Zn2+ function as cross-linkers; Zn2+ also functions as an antibacterial component and as nutrition for wound healing, and Si ions play a key role in determining the bioactivity of the hydrogel. With the controlled release of divalent ions, such as Ca2+ and Zn2+ from HS, the gelation process of the composite hydrogel could be efficiently controlled. In addition, in vitro results reveal that the composite hydrogel stimu...

Poly(d,l-lactide-co-glycolide) (PLGA) is widely used in a variety of tissue engineering and drug delivery applications due to its biodegradability and biocompatibility. But PLGA surfaces are usually hydrophobic which limited the loading and seeding capacities for cells, especially semiadherent immune cells. In this paper we described an attempt to improve the hydrophilicity and surface architecture for accommodating dendritic cells (DCs) that are widely used as professional antigen presenting cells in immune therapy of cancer and other diseases. The 3D porous PLGA scaffold was made by solvent casting/salt leaching of PLGA blended with surface functionalized multiwalled carbon nanotubes (F-MWCNTs). The incorporation and dispersion of F-MWCNT in the scaffold structures resulted in not only improved surface hydrophilicity but also nanoscale surface structure that would provide a preferable microenvironment for DCs attachment. We think such a scaffold material may be more desirable for immune cell delivery for immunotherapy. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 1045–1052, 2015.

A novel polysaccharide (GPP-S), with a molecular mass of 1.2 × 10(6) Da, was isolated from the tetraploid Gynostemma pentaphyllum Makino by alkali extraction followed by purifications using DEAE and Sephacryl S-400 column chromatographies. The monosaccharide composition of GPP-S was determined as rhamnose, arabinose, glucose, and galactose with a molar ratio of 1.00:3.72:19.49:7.82. The structural analysis suggested that the backbone of GPP-S is (1→4)-linked-glucose and (1→6)-linked-galactose with a (1→4,6)-linked-glucose branch every six monosaccharide residues. The terminals were 1-)-α-arabinose, glucuronic acid, and other monosaccharides. GPP-S exhibited scavenging capacities against hydroxyl, peroxyl, and DPPH(•) radicals in vitro. GPP-S also had inhibitory activities on IL-1β, IL-6, and COX-2 gene expressions in RAW 264.7 mouse macrophage cells. These results suggested that GPP-S could be developed as a bioactive ingredient for functional foods and dietary supplements.

The study investigated the dynamic process of internalization and intracellular processing of DOTAP/siRNA Lipoplexes and PEI/ siRNA, HPAMAM-PHE45/siRNA Polyplexes by H1299 cells. Fluorescence colocalization studies with a lysosomal marker-LysoTracker, revealed that DOTAP complexes could be quickly take up by cells into the cytoplasm, and most were released from endosomal pathway by 6 h. HPAMAM-PHE45 or PEI complexes were found to attach to the surface of the cell membrane initially. Some of the complexes followed the endosomal pathway, but also a part of complexes enter cells through caveolae-mediated endocytosis. We conclude that lipoplex uptake proceeds only by clathrin-mediated endocytosis, while Polyplexes are taken up by two mechanisms, involving caveolae and clathrin-mediated endocytosis. In this study, we compared the different siRNA uptake and intracellular processing of Polyplexes and Lipoplexes delivery systems basis optimization study in the future.

Kasper et al. have found that solar-wind helium could be heated to be nearly 7 times hotter than hydrogen on average from the observation of the Wind spacecraft. The stochastic Fermi mechanism is employed to investigate this phenomenon via the ion-cyclotron resonant process (Kasper J. C. et al., Phys. Rev. Lett., 110 (2013) 091102). Due to strong ion cyclotron resonances caused by counterpropagating Alfven waves, the helium could be thermalized to be 7 times hotter than hydrogen. In this paper, a new aspect, the non-resonant interaction between thermal non-equilibrium particles and turbulent Alfven waves, is utilized to illustrate the above observation analytically and numerically. The result of our model is broadly consistent with the observational result. Additionally, this paper predicts that the various temperature anisotropies of ions may exist in the solar-wind core which different thermal non-equilibrium factors lead to. This work builds up a close relation among non-resonant heating of thermal non-equilibrium ions, differential flow, and temperature anisotropy.

High-density lipoprotein (HDL) is a key mediator in reverse cholesterol transport and is involved in a mechanism known as 'selective lipid uptake', a process mediated by scavenger receptor B type I (SR‑BI), which is a HDL receptor. The aim of the present study was to investigate the therapeutic effect of the SR‑BI gene when delivered by combining cationic liposomal microbubbles (CLMs) and ultrasound (US) in hypercholesterolemic rats. Hypercholesterolemia was induced by administration of excessive doses of vitamin D3 and cholesterol in rats. The CLMs consisted of perfluoropropane gas encapsulated in a phospholipid shell using the sonication‑lyophilization method. The SR‑BI gene, mixed with the self‑made microbubbles, was transfected into hypercholesterolemic rat arteries using therapeutic US. SR‑BI protein expression was determined by western blot analysis 2 days post-transfection. Two weeks after transfection, total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL) and HDL serum concentrations were measured. Transfection efficiency of the SR‑BI gene in the SR‑BI + US/CLM group increased 6‑7‑fold compared with the SR‑BI group. Two weeks after transfection, plasma lipid levels in treated hypercholesterolemic rats were observed to be significantly reduced compared with rats that did not receive treatment. However, no significant change was observed in the SR‑BI group compared with that in the SR‑BI + US/CLM group. Results of the present study indicate that the combination of US and CLMs loaded with the SR‑BI gene may exert a protective role in hypercholesterolemia.

Regulation of gene expression using small interfering RNA (siRNA) is a promising strategy for treatments of numerous diseases. However, the progress towards broad application of siRNA requires the development of safe and effective vectors that target to specific cells. In this study, we developed a novel recombinant high density lipoprotein (rHDL) vector with high siRNA encapsulation efficiency.They were prepared by condensing siRNA with various commercial cationic polymers and coating the polyplex with a layer of lipids and apolipoprotein AI (apo AI). The rHDL nanoparticles were used to transfect SMMC-7721 hepatoma cells with stable luciferase expression. The uptake and intracellular trafficing of siRNA were also investigated.Characterization studies revealed these rHDL nanoparticles had similar physical properties as natural HDLs. The various rHDL formulations had high silencing efficiency (more than 70% knockdown) in hepatocytes with minimum cytotoxicity. Moreover, the uptake of rHDL by SMMC-7721 was confirmed to be mediated through the natural HDL uptake pathway.The work described here demonstrated the optimized rHDL nanoparticles may offer a promising tool for siRNA delivery to the liver.

Background A major obstacle to the application of gene therapy methods in experimental and clinical practice is the lack of safe and efficient gene delivery systems. Electroporation has been shown to an effective physical delivery method. A variety of factors have been shown to affect the electroporation-mediated gene delivery efficiency. In the present study, we assessed the usefulness of noncoding short-fragment DNA (sf-DNA) for facilitating electroporation-mediated gene transfer. Methods The plasmid pGL3-control encoding firefly luciferase was injected into tissues together with or without sf-DNA. Immediately after injection, the tissues were electroporated and the level of luciferase activity was assessed 24 h later. Different types of DNA fragments with different molecular weights, structures and doses were compared. The transfection efficiencies of sf-DNA-mediated electroporation in different tissues or with different electric field strengths were examined. Results Plasmid DNA formulated with 300-bp sf-DNA resulted in a significant improvement in electroporation-mediated gene transfer efficiency. The effect is dose-dependent and is also affected by DNA fragment length and structure. It was useful for intramuscular electroporation application, as well as intratumoral application with various pulse voltage parameters. Conclusions The data obtained in the present study indicate that sf-DNA can be used as a helper molecule to improve electroporation-mediated gene transfection efficiency. Copyright © 2012 John Wiley & Sons, Ltd.

4-[18F]flouro-3-nitro-N-2-propyn-1-yl-benzamide ([18F]FNPB) was developed as a new stable aromatic prosthetic group for more efficient click labeling of peptides. A new aromatic precursor 3,4-dinitro-N-2-propyn-1-yl-benzamide was radiofluorinated using [18F]KF/K2.2.2 followed by HPLC purification to obtain the desired product [18F]FNPB. [18F]FNPB was synthesized with a 58% radiochemical yield, a specific activity?>?350?GBq/mu mol, and radiochemical purity was exceeded 98% in 40?min. The in vitro stability studies showed no detectable radiodefluorination over 2?h in mouse plasma. The click labeling yield of three different peptides with [18F]FNPB were all above 87%. The in vitro study suggests that [18F]FNPB may be stable?in vivo and could have general application in labeling peptides with high radiochemical yield for positron emission tomography applications. Copyright (c) 2012 John Wiley & Sons, Ltd.

The angiopoietin–Tie2 binding and related signal transduction pathways are crucial for vascular angiogenesis, blood vessel integrity and maturation. In this study, we preformed a virtual screening of small molecules targeting to Tie2. The binding site was selected at the extracellular ligand binding region of Tie2, rather than its conventional endocellular ATP binding region. It was found that loperamide, a widely-used antidiarrhea drug, was among the top hits. The binding between loperamide and Tie2 was confirmed by surface plasmon resonance (SPR) assay. Loperamide competitively inhibited the binding of both angiopoietin1 and angiopoietin2. These results indicate that loperamide is an antagonist of angiopoietin1 and angiopoietin2.

Loperamide, an antidiarrhea drug, is a peripheral opiate agonist. Some other opiate agonists have been shown to promote cell apoptosis. In this research, we studied the apoptosis-inducing and cytotoxic activities of loperamide. MTT assay was used to determine its cytotoxicity on nine established human tumor cell lines. Cell apoptosis was detected by flow cytometry. Hypodiploid cells and cell cycles were analyzed by propidium iodide (PI) staining, while early apoptotic cells were detected by annexin V-FITC/PI staining. It was found that loperamide could inhibit the proliferation of the tested tumor cell lines. The IC₅₀ values for SMMC7721, MCF7, SPC-A1, SKOV3-DDP, H460, HepG2, SGC7901, U2OS, and ACHN cells were 24.2±2.1 μM, 23.6±2.5 μM, 25.9±3.1 μM, 27.1±2.5 μM, 41.4±2.1 μM, 23.7±1.3 μM, 35.4±3.5 μM, 11.8±2.8 μM, and 28.5±3.4 μM, respectively. Loperamide was more effective to the human osteosarcoma U2OS cells with an IC₅₀ value of 11.8±2.8 μM. Meanwhile, it could induce cell apoptosis and cause G2/M-phase cell cycle arrest. The apoptotic cells could be found when treating with loperamide for 6h and most of them belonged to early apoptosis. In loperamide-treated cells, activation of caspase-3 was found, namely that caspase-3 was involved in the loperamide-induced apoptosis. The results of these studies indicate that loperamide is a potential antitumor agent. To our knowledge, this is the first report on antitumor activity of loperamide.

Wound healing is a complicated process, and fibroblast is a major cell type that participates in the process. Recent studies have shown that bioglass (BG) can stimulate fibroblasts to secrete a multitude of growth factors that are critical for wound healing. Therefore, we hypothesize that BG can stimulate fibroblasts to have a higher bioactivity by secreting more bioactive growth factors and proteins as compared to untreated fibroblasts, and we aim to construct a bioactive skin tissue engineering graft for wound healing by using BG activated fibroblast sheet. Thus, the effects of BG on fibroblast behaviors were studied, and the bioactive skin tissue engineering grafts containing BG activated fibroblasts were applied to repair the full skin lesions on nude mouse. Results showed that BG stimulated fibroblasts to express some critical growth factors and important proteins including vascular endothelial growth factor, basic fibroblast growth factor, epidermal growth factor, collagen I, and fibronectin. In vivo results revealed that fibroblasts in the bioactive skin tissue engineering grafts migrated into wound bed, and the migration ability of fibroblasts was stimulated by BG. In addition, the bioactive BG activated fibroblast skin tissue engineering grafts could largely increase the blood vessel formation, enhance the production of collagen I, and stimulate the differentiation of fibroblasts into myofibroblasts in the wound site, which would finally accelerate wound healing. This study demonstrates that the BG activated skin tissue engineering grafts contain more critical growth factors and extracellular matrix proteins that are beneficial for wound healing as compared to untreated fibroblast cell sheets.

The neonatal Fc receptor for IgG (FcRn) is considered critical for the regulation of endogenous IgG and serum albumin (SA) and their circulation half-life in vivo. Both IgG and SA can bind to FcRn tightly at acidic pH but not so much at neutral pH. Here we reported a few novel single chain antibody fragments (scFv) obtained based on screening of a phage library. FnAb-8 and FnAb-12 can bind to human FcRn with higher affinities than IgG at acidic pH but similar or lower affinities than IgG at pH7.4. Fusion proteins consisted of the therapeutic peptide, GLP-1 (Glucagon-like peptide-1) connected to the N-terminus of FnAb-8 and FnAb-12, named as G8 and G12, were shown to retain the pH-dependent binding capabilities to FcRn while also bound to the GLP-1 receptor. In vivo efficacy studies in diet induced diabetes mice confirmed the GLP-1 receptor (GLP-1R) agonist activities and sustained blood sugar lowering effect. In vivo pharmacokinetics (PK) studies were performed in nonhuman primates and FnAb-8 was found to have circulation half-life several folds longer than what have been reported for scFvs. G8 may be developed into long acting GLP-1R agonists with great potentials in clinical applications.

Computed tomography (CT) imaging is a valuable tool for the diagnosis of colorectal diseases. However, the colonic wall depiction in 2D CT images is usually poor because of the low contrast between the colonic wall and the luminal content. In order to improve the visualization of the colonic wall and any abnormality on its surface, we report in this paper the development of an oil-free foam fluid negative contrast medium for improved CT imaging of the colon. The foam fluid negative contrast medium was prepared by dispersing and stabilizing microbubbles in a polymeric solution. The stabilities of both the individual bubbles and the foam fluid system were optimized by incorporating bovine serum albumin and gluconolactone as the stabilization agent. The medium had a mean X-ray density of −120 Hounsfield units (close to that of the extraluminal tissues), and enabled clear 2D visualization of the colonic wall in both ex vivo and in vivo imaging studies. The measured colonic wall thicknesses at different segments in a beagle dog based on the 2D CT images obtained with the negative contrast medium accurately reflected the anatomical values, as compared with the values based on air-contrasted images. In vivo study of a simulated polyps pig model demonstrated sensitive detection of 11 out of 12 polyps with the smallest one 2 mm in diameter. We believe this new and safe foam fluid negative medium would enable the implementation of CT imaging as a convenient and useful tool for diagnosis of colon cancer, especially in the elderly population. Copyright © 2011 John Wiley & Sons, Ltd.