PEGylated catalase prevents metastatic tumor growth aggravated by tumor removal.

Although surgical removal is a primary option for treating tumors, it can lead to the increased growth of metastatic tumors. Because surgical procedures may generate reactive oxygen species (ROS), known promoters of tumor metastasis and growth, we investigated whether PEGylated catalase (PEG-catalase, plasma half-life of 13.6 h) was able to prevent this after surgical removal of a footpad tumor in mice.

Fetuin mediates hepatic uptake of negatively charged nanoparticles via scavenger receptor.

We tried to evaluate the possible involvement of fetuin in the scavenger receptors (SRs)-mediated hepatic uptake of polystyrene nanospheres with the size of 50 nm (NS-50), which has surface negative charge (zeta potential=-21.8+/-2.3 mV).

Inhibition of peritoneal dissemination of tumor cells by single dosing of phosphodiester CpG oligonucleotide/cationic liposome complex.

Although unmethylated CpG dinucleotide-containing oligodeoxynucleotides (CpG ODN) are able to inhibit tumor metastasis through the induction of antitumor immunity, their stability and delivery to antigen presenting cells needs to be improved. In this study, we formulated a CpG ODN complex with cationic liposomes (CpG ODN-lipoplex) and its antitumor activity was evaluated in peritoneal dissemination models of tumor cells stably labeled with firefly luciferase gene. A single intraperitoneal administration of CpG ODN-lipoplex greatly reduced the number of tumor cells to 0.

The potential role of fucosylated cationic liposome/NFkappaB decoy complexes in the treatment of cytokine-related liver disease.

Cytokine production by Kupffer cells, which is regulated by NFkappaB, causes severe liver injury in endotoxin syndrome. NFkappaB decoy has been reported to inhibit NFkappaB-mediated transcription. The purpose of this study is to inhibit LPS-induced cytokine production by Kupffer cell-targeted delivery of NFkappaB decoy using fucosylated cationic liposomes (Fuc-liposomes).

Incorporation into a biodegradable hyaluronic acid matrix enhances in vivo efficacy of recombinant human interleukin 11 (rhIL11).

In order to improve the therapeutic efficacy of recombinant human interleukin 11 (rhIL11) and to reduce its frequency of administration, the feasibility of a sustained release formulation consisting of hyaluronic acid (HyA) was investigated. rhIL11 was mixed together with an aqueous solution of HyA or HyA and protamine, and the mixture was lyophilized. The resulting powder was compressed into pellet and was subcutaneously administered in the rats.

Intracellular trafficking is the important process that determines the optimal charge ratio on transfection by galactosylated lipoplex in HEPG2 cells.

The purpose of the present study was to gain insight into the major factors affecting transfection efficiency with galactosylated lipoplex in HepG2 cells. In this study, lipoplex and galactosylated lipoplex were examined at different charge ratios (- : +): 1.0 : 1.

Role of tyrosine and tryptophan in chemically modified serum albumin on its tissue distribution.

To investigate the effect of functional groups in bovine serum albumin (BSA) on its tissue distribution characteristics, tyrosine (Tyr) or tryptophan (Trp) residues of BSA were chemically modified by tetranitromethane (TNM) and 2-hydroxy-5-nitrobenzyl bromide (HNB), respectively. BSA was successfully modified with each reagent depending on the amount of the reagent added to the reaction mixture, and TNM- and HNB-modified BSA derivatives with different degrees of modification were obtained. Circular dichroism measurements showed that slight secondary and large tertiary changes were detectable as the degree of modification increased.

Effect of mannose density on mannose receptor-mediated cellular uptake of mannosylated O/W emulsions by macrophages.

Carbohydrate grafted emulsions are one of the most promising cell-specific targeting systems for lipophilic drugs. We have previously reported that mannosylated (Man-) emulsions composed of soybean oil, EggPC and cholesten-5-yloxy-N-(4-((1-imino-2-d-thiomannosylethyl)amino)alkyl)formamide (Man-C4-Chol) with a ratio of 70:25:5 were significantly delivered to liver non-parenchymal cells (NPC) via mannose receptor-mediated mechanism after intravenous administration in mice. Since the efficient targeting through a receptor-mediated mechanism is largely controlled by ligand-receptor interaction, the effect of mannose density on Man-emulsions was studied with regard to both the disposition in vivo in mice and the uptake in vitro, using elicited macrophages which express a number of mannose receptors.

[Pharmaceutical device of IFN].

Recently, new types of interferon (IFN) agents, such as pegylated IFN (PEG-IFN) and consensus IFN, have been developed for strong therapeutic effect and used in clinical stage. PEG-IFN, which is the conjugation of IFN and polyethylene glycol, was designed to long circulate in blood and decrease antibody production. Consensus IFN was designed to combine amino acid frequently appeared in IFN-alpha subtypes.

Effect of the particle size of galactosylated lipoplex on hepatocyte-selective gene transfection after intraportal administration.

The purpose of this study was to examine the effect of the size of galactosylated cationic liposome (Gal-liposome)/plasmid DNA complex (Gal-lipoplex) on hepatocyte-selective gene transfection after intraportal administration. pCMV-Luc was selected as a model plasmid DNA. After intraportal administration of Gal-lipoplex to mice, the hepatic and intrahepatic gene expression was evaluated.

Biodistribution characteristics of amino acid dendrimers and their PEGylated derivatives after intravenous administration.

In this study, we synthesized dendritic poly(L-lysine)s (DPKs), dendritic poly(L-ornithine)s (DPOs), which are constructed as novel amino acid dendrimers, and PEGylated KG6 (the sixth generation of DPKs), and evaluated the physicochemical properties and biodistribution characteristics of these dendrimers. The particle size of DPKs and DPOs was well controlled in the nanometer range. The zeta-potential of these dendrimers was slightly positive and this gradually increased in association with their generation.

Inhibition of liver metastasis by all-trans retinoic acid incorporated into O/W emulsions in mice.

All-trans retinoic acid (ATRA) was incorporated into lipid emulsions in an attempt to alter its distribution characteristics and improve its inhibition of liver cancer metastasis. Lipid emulsions composed of egg phosphatidylcholine, cholesterol, and soybean oil were the optimized carriers for ATRA delivery, as shown by the submicron particle size and high incorporation efficiency. The particle size and zeta potential of ATRA incorporated into emulsions were about 133 nm and -11 mV, respectively.

Intravenous administration of mannosylated cationic liposome/NFkappaB decoy complexes effectively prevent LPS-induced cytokine production in a murine liver failure model.

The purpose of this study was to inhibit endotoxin induced cytokines production and liver injury by liver non-parenchymal cell (NPC) selective delivery of nuclear factor kappaB (NFkappaB) decoy using mannosylated cationic liposomes (Man-liposomes). In this study, we examined the distribution, inhibitory effect on cytokines production and ALT/AST of intravenously injected Man-liposome/NFkappaB decoy complex. Man-liposome/[(32)P] NFkappaB decoy complexes mostly accumulated in the liver, preferentially in NPC.

[Comparison of LCD and CRT monitors for detection of pulmonary nodules and interstitial lung diseases on digital chest radiographs by using receiver operating characteristic analysis].

Soft copy reading of digital images has been practiced commonly in the PACS environment. In this study, we compared liquid-crystal display (LCD) and cathode-ray tube (CRT) monitors for detection of pulmonary nodules and interstitial lung diseases on digital chest radiographs by using receiver operating characteristic (ROC) analysis. Digital chest images with a 1000x1000 matrix size and a 8 bit grayscale were displayed on LCD/CRT monitor with 2M pixels in each observer test.

Visualization of large-scale aqueous solubility data using a novel hierarchical data visualization technique.

It is a difficult task to recognize the trends in molecular physical properties relevant to a specific chemical class and find a way to optimize potential compounds. We present here a novel hierarchical data visualization technique, named "HeiankyoView", to visualize large-scale multidimensional chemical information. HeiankyoView represents hierarchically organized data objects by mapping leaf nodes as colored square icons and nonleaf nodes as rectangular borders.

Efficient gene transfer into macrophages and dendritic cells by in vivo gene delivery with mannosylated lipoplex via the intraperitoneal route.

In this study, we developed an antigen-presenting cell (APC)-selective intraperitoneal (i.p.) gene delivery system with mannosylated cationic liposomes (Man-liposomes)/plasmid DNA complex (Man-lipoplex).

Inhibition of tumour metastasis by targeted delivery of antioxidant enzymes.

Metastasis is one of the most harmful aspects of malignant neoplasm. Interaction of tumour cells with normal cells such as tissue macrophages may generate reactive oxygen species, which would affect various aspects of tumour metastasis. Reactive oxygen species cause damage to both tumour and normal cells and some of them, especially hydrogen peroxide, can also act as intracellular second messengers at sublethal concentrations to increase the transcription of various genes, which can then accelerate the proliferation of tumour cells in metastatic colonies.

Enhanced DNA vaccine potency by mannosylated lipoplex after intraperitoneal administration.

Background: Here we describe a novel DNA vaccine formulation that can enhance cytotoxic T lymphocyte (CTL) activity through efficient gene delivery to dendritic cells (DCs) by mannose receptor-mediated endocytosis.

Methods: Ovalbumin (OVA) was selected as a model antigen for vaccination; accordingly, OVA-encoding pDNA (pCMV-OVA) was constructed to evaluate DNA vaccination. Mannosylated cationic liposomes (Man-liposomes) were prepared using cholesten-5-yloxy-N-{4-[(1-imino-2-D-thiomannosylethyl)amino]butyl}formamide (Man-C4-Chol) with cationic lipid.

Analysis of the molecular interaction between mannosylated proteins and serum mannan-binding lectins.

The kinetics and specificity of the molecular interaction between proteins modified with varying numbers of mannose residues and isolated rabbit mannan-binding lectin (MBL) were characterized by using surface plasmon resonance spectroscopy (SPR). Mannosylated bovine serum albumin (Man-BSA) with different numbers of mannoses and other mannosylated derivatives of lysozyme (LZM), soybean trypsin inhibitor (STI), superoxide dismutase (SOD) and bovine gamma-immunoglobulin (IgG) were synthesized. Rabbit MBL was isolated by affinity column chromatography and immobilized on the SPR sensor chip via avidin-biotin binding.

Influence of cholesterol composition on the association of serum mannan-binding proteins with mannosylated liposomes.

In our previous studies, serum mannan-binding protein (MBP) accelerated the uptake by cultured macrophages. The present study was initiated to investigate the kinetics of molecular interaction between mannosylated liposomes and MBP in more details and the effects of lipid composition on the interaction. The analysis was carried out by surface plasmon spectroscopy (SPR) methods, using rabbit serum MBP isolated by affinity chromatography.

Analysis of the molecular interaction of glycosylated proteins with rabbit liver asialoglycoprotein receptors using surface plasmon resonance spectroscopy.

A sensitive, accurate, and efficient biosensor analysis using surface plasmon resonance (SPR) spectroscopy was used for delineating the molecular interaction between rabbit liver asialoglycoprotein receptors (ASGPR) and glycosylated proteins. Isolated rabbit liver ASGPR obtained by affinity column chromatography was dissolved in buffer solution containing TritonX-100 and immobilized on the SPR sensor chip by amine coupling. The SPR study demonstrated that the association rate constants (ka) of galactosylated proteins with ASGPR are dependent on the number of galactose residues, while the dissociation rate constants (kd) are influenced not only by the surface density of the galactose moieties but also by their steric configuration.

Suppression of TNFalpha production in LPS induced liver failure in mice after intravenous injection of cationic liposomes/NFkappaB decoy complex.

NFkappaB decoy, double stranded oligonucleotides containing NFkappaB binding sequences, inhibits NFkappaB-mediated production of inflammatory cytokines, and therefore NFkappaB decoy has been applied to several diseases. However, naked NFkappaB decoy, which is quickly cleared from the circulation in mice after intravenous injection, is readily absorbed into the systemic circulation. In order to deliver enough NFkappaB decoy for a therapeutic effect, it is necessary to develop a carrier, which enables much more NFkappaKB decoy to transfer to the target cells.

Physicochemical and pharmacokinetic characteristics of cationic liposomes.

After intravenous administration of plasmid DNA (pDNA)/cationic liposome complexes, the gene expression is predominantly observed in the lung due to the physicochemical properties of the liposome complexes and the physiology of the lung. To determine the physicochemical properties and distribution behavior of cationic liposomes for lung-selective drug and/or gene delivery systems, N-[1-(2,3-dioleyloxy)propyl]-n,n,n-trimethylammonium chloride (DOTMA)/cholesterol and 1,2-dioleoyl-3-trimethyl-ammoniopropane (DOTAP)/cholesterol liposomes were studied. The particle sizes of DOTMA/cholesterol and DOTAP/cholesterol liposomes were very similar: 126 and 128 nm, respectively.

Evaluation of proinflammatory cytokine production induced by linear and branched polyethylenimine/plasmid DNA complexes in mice.

The purpose of this study was to evaluate the cytokine response induced by linear and branched polyethylenimine (PEI)/plasmid DNA (pDNA) complex (polyplex) in relation to the ratio of PEI nitrogen and DNA phosphate (N/P ratio) of the polyplex, dose of pDNA, and structure and molecular weight of PEI, which are important for transfection efficacy of PEI polyplex. As a control, a N-[1-(2, 3-dioleyloxy) propyl]-n,n,n-trimethylammonium chloride/cholesterol liposome/pDNA complex (lipoplex) was selected for its high transfection efficacy in vivo. The concentration of proinflammatory cytokines such as tumor necrosis factor (TNF)-alpha were much lower after the administration of polyplex than lipoplex irrespective of the N/P ratio, dose of pDNA, or structure and molecular weight of PEI, although these factors affected the transfection efficacy in vivo.

Novel PEG-matrix metalloproteinase-2 cleavable peptide-lipid containing galactosylated liposomes for hepatocellular carcinoma-selective targeting.

In order to obtain an HCC-selective drug delivery system, a novel functional lipid, which is cleaved by the protease activity of matrix metalloproteinase-2 (MMP-2), was developed. The amino group of dioleoylphosphatidylethanolamine (DOPE) was conjugated with PEGylated MMP-2 substrate peptide (Gly-Pro-Leu-Gly-Ile-Ala-Gly-Gln), and MMP-2-cleavable PEG-Peptide-DOPE (PEG-PD) was synthesized. When PEG-PD was incorporated in galactosylated liposomes (Gal-PEG-PD-liposomes), we expected that Gal-PEG-PD-liposomes would not be taken up by normal hepatocytes due to the steric hindrance effect, but would be activated around HCC cells by secreted MMPs.