Bionanocapsule

Quartz-crystal-microbalance (QCM) biosensor is a typical label-free biosensor, and its sensitivity can be greatly improved by removing electrodes and wires that would be otherwise attached to the surfaces of the quartz resonator. The wireless-electrodeless QCM biosensor was then developed using a microelectro-mechanical systems (MEMS) process, although challenges remain in the sensitivity, the coupling efficiency, and the miniaturization (or mass production). In this study, we establish a MEMS process to obtain a large number of identical ultrasensitive and highly efficient sensor chips with dimensions of 6 mm square...

BACKGROUND: The uterus is an organ that is directly accessible via the transvaginal route, whereas drug delivery system or gene delivery system (GDS) for the uterus are very limited even in animal models. In this study, we optimized a bionanocapsule (BNC) that is a hepatitis B virus (HBV) envelope L-protein particle, of which the structurally similar particle has been used as an immunogen of a conventional HB vaccine worldwide for more than 30 years, as a local uterine GDS using a mouse model...

Biodegradable nanometer-sized particles have novel structural and physical properties that are attracting great interests from pharmaceuticals for the targeted delivery of anticancer drugs and imaging contrast agents. These smart nanoparticles are designed to ferry chemotherapeutic agents or therapeutic genes into malignant cells while sparing healthy cells. In this review, we describe currently clinically used chemotherapeutics in nanoparticle formulation and discuss the current status of nanoparticles developed as targeting delivery systems for anticancer drugs, with emphasis on formulations of micelles, liposome, polymeric nanoparticles, gold nanoparticle dendrimers, and bionanocapsules...

Bionanocapsules (BNCs) are hollow nanoparticles consisting of hepatitis B virus (HBV) envelope L proteins and have been shown to deliver drugs and genes specifically to human hepatic tissues by utilizing HBV-derived infection machinery. The complex of BNCs with liposomes (LPs), the BNC-LP complexes (a LP surrounded by BNCs in a rugged spherical form), could also become active targeting nanocarriers by the BNC function. In this study, under acidic conditions and high temperature, BNCs were found to fully fuse with LPs (smooth-surfaced spherical form), deploying L proteins with a membrane topology similar to that of BNCs (ie, virosomes displaying L proteins)...

Chronic hepatitis B virus (HBV) infection is a major cause of hepatocellular carcinoma (HCC). To date, the lack of efficient in vitro systems supporting HBV infection and replication has been a major limitation of HBV research. Although primary human hepatocytes support the complete HBV life cycle, their limited availability and difficulties with gene transduction remain problematic. Here, we used human primary hepatocytes isolated from humanized chimeric uPA/SCID mice as efficient sources. These hepatocytes supported HBV replication in vitro...

Chlorotoxin is a 36-amino acid peptide derived from Leiurus quinquestriatus (scorpion) venom, which has been shown to inhibit low-conductance chloride channels in colonic epithelial cells. Chlorotoxin also binds to matrix metalloproteinase-2 and other proteins on glioma cell surfaces. Glioma cells are considered to require the activation of matrix metalloproteinase-2 during invasion and migration. In this study, for targeting glioma, we designed two types of recombinant chlorotoxin fused to human IgG-Fcs with/without a hinge region...

Dendritic cells (DCs) are key regulators of adaptive T-cell responses. By capturing exogenous antigens and presenting antigen-derived peptides via major histocompatibility complex molecules to naïve T cells, DCs induce antigen-specific immune responses in vivo. In order to induce effective host immune responses, active delivery of exogenous antigens to DCs is considered important for future vaccine development. We recently generated bionanocapsules (BNCs) consisting of hepatitis B virus surface antigens that mediate stringent in vivo cell targeting and efficient endosomal escape, and after the fusion with liposomes (LP) containing therapeutic materials, the BNC-LP complexes deliver them to human liver-derived tissues in vivo...

Hepatitis B virus (HBV) envelope L proteins, when synthesized in yeast cells, form a hollow bionanocapsule (BNC) in which genes (including large plasmids up to 40 kbp), small interfering RNA (siRNA), drugs, and proteins can be enclosed by electroporation. BNCs made from L proteins have several advantages as a delivery system: Because they display a human liver-specific receptor (the pre-S region of the L protein) on their surface, BNCs can efficiently and specifically deliver their contents to human liver-derived cells and tissues ex vivo (in cell culture) and in vivo (in a mouse xenograft model)...

Targeting and down-regulation of ErbB2, a member of EGF receptor family, is regarded as one of the key aspect for cancer treatment because it is often overexpressed in breast and ovarian cancer cells. Although natural ligands for ErbB2 have not been found, unlike other ErbB receptors, EC-1, a 20-amino acid circular peptide, has been shown to bind to ErbB2 as an artificial ligand. Previously we showed EC-1 peptide did not induce the internalization of ErbB2 in SK-BR-3 cells. In this report, we designed divalent and multivalent forms of EC-1 peptide with the Fc portion of the human IgG and bionanocapsule modified with ZZ-tag on its surface to improve the interaction with ErbB2...

A novel HER2-targeted carrier was developed using bionanocapsules (BNCs). Bionanocapsules (BNCs) are 100-nm hollow nanoparticles composed of the L-protein of hepatitis B virus surface antigen. An affibody of HER2 was genetically displayed on the BNC surface (Z(HER2)-BNC). For the investigation of binding affinity, Z(HER2)-BNC was incubated with the cancer cell lines SK-BR-3 (HER2 positive), and MDA-MB-231 (HER2 negative). For analysis of HER2 targeting specificity, Z(HER2)-BNC or Z(WT)-BNC (without affibody) was incubated with both SK-BR-3 and MDA-MB-231 cells by time lapse and concentration...

Recently, our group has proposed a novel gene-regulation system responding to cAMP-dependent protein kinase (PKA) that has been applied to living cells. In this study, human liver-specific bionanocapsules (BNCs) are used as a gene-delivery system to increase transfection efficiency and to target specific cell types. BNCs can efficiently deliver a target gene to human hepatocytes and hepatoma cells in vitro or in vivo. The combination of a signal-responsive gene-delivery system with BNCs led to an increase in the transfection efficiency and selectivity for hepatoma cells...

Hepatoma (hepatocellular carcinoma) is the most common type of malignant tumor originating in the liver and has a relatively low 5-year survival rate. The development of hepatoma-targeted therapy is needed to increase treatment efficiency and to reduce the incidence of undesirable side effects. In this study we developed a novel hepatoma-targeted gene delivery system. The gene delivery system was prepared by combining a human liver cell-specific bionanocapsule (BNC) and a tumor cell-specific gene regulation polymer, which responds to hyperactivated protein kinase C alpha in hepatoma cells...

Macromolecules that can assemble a large number of enzyme and antibody molecules have been used frequently for improvement of sensitivities in enzyme-linked immunosorbent assays (ELISAs). We generated bionanocapsules (BNCs) of approximately 30nm displaying immunoglobulin G (IgG) Fc-binding ZZ domains derived from Staphylococcus aureus protein A (designated as ZZ-BNC). In the conventional ELISA using primary antibody and horseradish peroxidase-labeled secondary antibody for detecting antigen on the solid phase, ZZ-BNCs in the aqueous phase gave an approximately 10-fold higher signal...

Bionanocapsule (BNC) is hollow nanoparticle composed of the l-protein of the hepatitis B virus surface antigen. BNC allows targeted delivery of either genes or drugs only to hepatocytes, but not to other cell types. In this study, we attempted to alter the specificity of BNC by insertion of biotin-acceptor peptide (BAP), which is efficiently biotinylated using biotin ligase BirA from Escherichia coli. Using streptavidin as a linker, biotinylated BNC could be display various biotinylated ligands that are otherwise difficult to fuse with BNC, such as antibodies, synthetic peptides and functional molecules...

Bionanocapsule (BNC) is a hollow nanoparticle composed of L-protein of the hepatitis B virus surface antigen. BNC can deliver genes or drugs into specific human hepatocytes, but delivery is limited to hepatocytes. In this study, we attempted to alter the specificity of BNCs by genetically introducing cell-penetrating peptides (CPPs), such as arginine-rich peptides, into BNCs. The CPP-fused BNC was efficiently internalized into various cell lines in a short period without significant cytotoxicity. These results show that CPP-BNC could be applied as an efficient carrier for gene and drug delivery...

Insect cell expression systems are widely used to produce active recombinant proteins. Here, we have developed a high-level expression vector containing a selectable marker for continuous production of recombinant proteins in insect cells. The plasmid, pXIHAbla, developed in this study, established a polyclonal cell line 8 days shorter than pXINSECT-DEST38 and pBmAneo. In addition, pXIHAbla exhibited an approximately fivefold higher average enhanced GFP expression level and approximately a twofold higher bionanocapsule secretion level than pXINSECT-DEST38...

Being the most delicate organ of the body, the brain is protected against potentially toxic substances by the blood-brain barrier (BBB), which restricts the entry of most pharmaceuticals into the brain. The developmental process for new drugs for the treatment of CNS disorders has not kept pace with progress in molecular neurosciences because most of the new drugs discovered are unable to cross the BBB. The clinical failure of CNS drug delivery may be attributed largely to a lack of appropriate drug delivery systems...

Bionanocapsules (BNCs) are nanoparticles with a high biocompatibility composed of the L protein of the hepatitis B virus surface antigen. BNC can deliver bioactive molecules to hepatocytes efficiently and specifically. However, delivery is limited to hepatocytes and incorporation of proteins into BNC is quite troublesome. Here, in order to alter the specificity of BNC and to achieve efficient protein delivery, we developed engineered BNC displaying the ZZ domain of protein A and incorporating enhanced green fluorescent protein (EGFP) inside the particles using an insect cell expression system...

Metastasis is a key aspect of tumor malignancy, and several malignant tumors show expression of various mature N-type glycans. In particular, beta1-6 branching N-acetylglucosamine (GlcNAc) is abundantly expressed as a part of high-mannose glycans in various highly metastatic cancers. Phaseolus vulgaris agglutinin-L(4) isolectin (L(4)-PHA), which adheres to beta1-6 GlcNAc specifically, has been used for in situ cancer diagnosis. Bionanocapsules (BNCs), hollow particles with a diameter of approximately 80 nm and composed of hepatitis B surface antigen (HBsAg) and a lipid bilayer, have been developed as human liver-specific nanocapsules for in vivo drug delivery system...

Bionanocapsules (BNCs) are hollow nanoparticles that are composed of L protein (the hepatitis B virus surface antigen) and show specific affinity for human hepatocytes. The pre-S1 peptide displayed on the surface of BNCs is the specific ligand for binding to the receptor on human hepatocytes. Therefore, BNCs are not delivered to other tissues, such as the brain. The aim of the present study was to develop a novel drug delivery system (DDS) targeting brain tumors using BNCs that selectively targeted brain tumors...