Inflammation-Triggering Engineered Macrophages (MacTriggers) Enhance Reactivity of Immune Checkpoint Inhibitor Only in Tumor Tissues.

We have previously reported engineered macrophages (MacTriggers) that can accelerate the release of tumor necrosis factor-α in response to M2 polarization. MacTriggers are characterized by two original characteristics of macrophages: (1) migration to tumors; and (2) polarization to the M2 phenotype in tumors. Intravenously administered MacTriggers efficiently accumulated in the tumors and induced tumor-specific inflammation.

The effect of Fc region affinity of protein-based antibody-recruiting molecules on antibody-dependent cellular cytotoxicity.

Previously, we reported anticancer molecules, Fc-binding antibody-recruiting molecules (Fc-ARMs), which crosslink proteins on cancer cells with endogenous immunoglobulin Gs (IgGs) their Fc region. The mobilized IgGs on cancer cells can accommodate natural killer cells to induce antibody-dependent cellular cytotoxicity (ADCC). Because previous Fc-ARMs utilized Fc-binding peptides, their affinity to IgGs is weak, which resulted in the limited induction capability of ADCC.

In vitro evaluation of novel SN-38 prodrug activated by α-rhamnosidase of exogenous enzyme.

This study introduces the α-rhamnose (Rham)-conjugated prodrug of SN-38 (Rham-SN-38) as a promising alternative to irinotecan. α-rhamnosidase, responsible for SN-38 release from Rham-SN-38, does not express in human cells, minimizing individual variability and side effects. The injection of the α-rhamnosidase into the tumor tissues makes it possible, for the first time, to activate the Rham-SN-38.

Effective design of PEGylated polyion complex (PIC) nanoparticles for enhancing PIC internalisation in cells utilising block copolymer combinations with mismatched ionic chain lengths.

In nanomedicine, PEGylation of nanomaterials poses a dilemma since it inhibits their interaction with target cells and enables their retention in target tissues despite its biocompatibility and nonspecific internalisation suppression. PEGylated polypeptide-based polyion complexes (PICs) are fabricated the self-assembly of PEGylated aniomers and homocatiomers based on electrostatic interactions. We propose that various parameters like block copolymer design and PIC domain characteristics can enhance the cell-PEGylated PIC interactions.

Dynamic frustrated charge hotspots created by charge density modulation sequester globular proteins into complex coacervates.

This study presents a simple strategy for the sequestration of globular proteins as clients into synthetic polypeptide-based complex coacervates as a scaffold, thereby recapitulating the scaffold-client interaction found in biological condensates. Considering the low net charges of scaffold proteins participating in biological condensates, the linear charge density () on the polyanion, polyethylene glycol--poly(aspartic acids), was reduced by introducing hydroxypropyl or butyl moieties as a charge-neutral pendant group. Complex coacervate prepared from the series of reduced- polyanions and the polycation, homo-poly-l-lysine, could act as a scaffold that sequestered various globular proteins with high encapsulation efficiency (>80%), which sometimes involved further agglomerations in the coacervates.

Engineered macrophages acting as a trigger to induce inflammation only in tumor tissues.

Herein, we report engineered macrophages, termed "MacTrigger," acting as a trigger to induce an inflammatory environment only in tumor tissues. This led to intensive anti-tumor effects based on the removal potential of foreign substances. The strength of this study is the utilization of two unique functions of macrophages: (1) their ability to migrate to tumor tissues and (2) polarization into the anti-inflammatory M2 phenotype in the presence of tumor tissues.

Engineered macrophages acting as a trigger to induce inflammation only in tumor tissues based on arginase 1-responsive TNF-α accelerated release.

Herein, we report engineered macrophages, termed "MacTrigger," acting as a trigger to induce an inflammatory environment only in tumor tissues. This led to intensive anti-tumor effects based on the removal potential of foreign substances. The strength of this study is the utilization of two unique functions of macrophages: (1) their ability to migrate to tumor tissues and (2) polarization into the anti-inflammatory M2 phenotype in the presence of tumor tissues.

A human cell orthogonal enzyme β-D-galacturonidase for sensitive detection of antigen proteins.

Enzymes are used to amplify signals for detection of antigen proteins in biological samples. However, the enzymes conventionally used for this purpose have limitations, such as the presence of the same (, endogenous) activity in human cells and difficulty in simultaneous use of multiple enzymes because of differences in their required reaction conditions. In this report, we identify an enzyme that can overcome these problems: β-D-galacturonidase (GalUAase) from .

[Development of New Sublingual Formulation for Transmucosal Delivery of Peptides].

Since oral bioavailability of peptides is extremely low, self-injectable and intranasal formulations have been developed; however, these treatments have problems such as storage and discomfort. The sublingual route is considered suitable for peptide absorption because there is less peptidase and it is not subject to hepatic first-pass effects. In this study, we attempted to develop a new jelly formulation for sublingual delivery of peptides.

Characterization of polypropyleneimine as an alternative transfection reagent.

Polypropyleneimine (PPI) was examined as a transfection reagent comparing with most widely used polymer, polyethyleneimine (PEI). PPI had better responsiveness to the endosomal pH and showed more condensation ability of plasmid DNA than PEI. Although the cytotoxicity of PPI was somewhat higher than PEI, the transfection efficacy of PPI was comparable with PEI or higher than PEI in some cell line.

Facile preparation of hexagonal nanosheets polyion complex formation from α-helical polypeptides and polyphosphate-based molecules.

The polyion complex-based supramolecular self-assembly of hexagonal nanosheets was achieved the complexation of a PEGylated block catiomer with ATP and other polyphosphate-containing small molecules. The formation of hexagonal nanosheets required the presence of a polyethylene glycol block and α-helix formation in the catiomer block, which was induced by complexation with the polyphosphate moiety.

A Mouse Model for Tuberculosis Combined With Inhalable Imiquimod-PLGA Nanocomposite Particles Based on Macrophage Phenotype.

Background/aim: In vivo models of tuberculosis are effective tools for developing new drugs. The objective of this study was to prepare in vivo models for tuberculosis by utilizing nanocomposite particles (NCPs) containing imiquimod-loaded poly(lactic-co-glycolic acid) nanoparticles.

Materials And Methods: NCPs were prepared from dichloromethane with imiquimod and poly(lactic-co-glycolic acid) using a spray dryer.

Nanostructure Control of an Antibiotic-Based Polyion Complex Using a Series of Polycations with Different Side-Chain Modification Rates.

Developing nanovehicles for delivering antibiotics is a promising approach to overcome the issue of antibiotic resistance. This study aims to utilize a polyion complex (PICs) system for developing novel nanovehicles for polymyxin-type antibiotics, which are known as last resort drugs. The formation of antibiotic-based PIC nanostructures is investigated using colistimethate sodium (CMS), an anionic cyclic short peptide, and a series of block catiomers bearing different amounts of guanidinium moieties on their side chains.

Preparation of Micelles Encapsulating Doxorubicin and Their Anticancer Effect in Combination With Tranilast in 3D Spheroids and .

Background/aim: The objective of this study was to prepare doxorubicin encapsulated in micelles (DOX-micelles) using poly(hexadecanyloxyethylene glycol-lactate phosphate), which we recently synthesized, and to evaluate the anticancer effect of DOX-micelles in vitro and in vivo.

Materials And Methods: To evaluate the anticancer effect of DOX-micelles in vitro, three-dimensional spheroids composed of B16 mouse melanoma cells and fibroblasts were prepared by changing the ratio of cancer cells to fibroblasts. In addition, for efficient doxorubicin treatment of the cells present in the center of the spheroids, tranilast, an anti-fibrotic drug was added to the spheroids before treatment with DOX-micelles, then the amount of doxorubicin and cell viability of spheroids were evaluated.

Poly(Alkyloxyethylene-Lactate Phosphate) for Delivery of Doxorubicin: Synthesis and Characterization.

Background/aim: Serious side effects are associated with the use of doxorubicin. Nanoparticles as carriers for anticancer drugs are useful for reducing side effects and improving therapeutic effects. In this study, a polymer for preparing doxorubicin-containing nanoparticles was developed.

Immunosuppressive mesenchymal stem cells aggregates incorporating hydrogel microspheres promote an in vitro invasion of cancer cells.

Introduction: The objective of this study is to design a co-culture system of cancer cells and three-dimensional (3D) mesenchymal stem cells (MSC) aggregates for the in vitro evaluation of cancer invasion.

Methods: First, the MSC of an immunosuppressive phenotype (MSC2) were prepared by the MSC stimulation of polyriboinosinic polyribocytidylic acid. By simple mixing MSC2 and gelatin hydrogel microspheres (GM) in a U-bottomed well of 96 well plates which had been pre-coated with poly (vinyl alcohol), 3D MSC2 aggregates incorporating GM were obtained.

Strategies Using Gelatin Microparticles for Regenerative Therapy and Drug Screening Applications.

Gelatin, a denatured form of collagen, is an attractive biomaterial for biotechnology. In particular, gelatin particles have been noted due to their attractive properties as drug carriers. The drug release from gelatin particles can be easily controlled by the crosslinking degree of gelatin molecule, responding to the purpose of the research.

Efficient cell transplantation combining injectable hydrogels with control release of growth factors.

Introduction: The objective of this study is to investigate the effect of gelatin microspheres incorporating growth factors on the therapeutic efficacy in cell transplantation. The strength of this study is to combine gelatin hydrogel microspheres incorporating basic fibroblast growth factor and platelet growth factor mixture (GM/GF) with bioabsorbable injectable hydrogels (iGel) for transplantation of adipose-derived stem cells (ASCs).

Methods: The rats ASCs suspended in various solutions were transplanted in masseter muscle.

Biomaterial-Assisted Regenerative Medicine.

This review aims to show case recent regenerative medicine based on biomaterial technologies. Regenerative medicine has arousing substantial interest throughout the world, with "The enhancement of cell activity" one of the essential concepts for the development of regenerative medicine. For example, drug research on drug screening is an important field of regenerative medicine, with the purpose of efficient evaluation of drug effects.

Three-Dimensional Culture System of Cancer Cells Combined with Biomaterials for Drug Screening.

Anticancer drug screening is one of the most important research and development processes to develop new drugs for cancer treatment. However, there is a problem resulting in gaps between the in vitro drug screening and preclinical or clinical study. This is mainly because the condition of cancer cell culture is quite different from that in vivo.

A Co-Culture System of Three-Dimensional Tumor-Associated Macrophages and Three-Dimensional Cancer-Associated Fibroblasts Combined with Biomolecule Release for Cancer Cell Migration.

The objective of this study is to design a cancer invasion model by making use of cancer-associated fibroblasts (CAF) or tumor-associated macrophages (TAM) and gelatin hydrogel microspheres (GM) for the sustained release of drugs. The GM containing adenosine (A) (GM-A) were prepared and cultured with TAM to obtain three-dimensional (3D) TAM aggregates incorporating GM-A (3D TAM-GM-A). The GM-A incorporation enabled TAM to enhance the secretion level of vascular endothelial growth factor.

A cancer invasion model of cancer-associated fibroblasts aggregates combined with TGF-β1 release system.

Introduction: The objective of this study is to design a cancer invasion model where the cancer invasion rate can be regulated .

Methods: Cancer-associated fibroblasts (CAF) aggregates incorporating gelatin hydrogel microspheres (GM) containing various concentrations of transforming growth factor-β1 (TGF-β1) (CAF-GM-TGF-β1) were prepared. Alpha-smooth muscle actin (α-SMA) for the CAF aggregates was measured to investigate the CAF activation level by changing the concentration of TGF-β1.

A Cancer Invasion Model Combined with Cancer-Associated Fibroblasts Aggregates Incorporating Gelatin Hydrogel Microspheres Containing a p53 Inhibitor.

The objective of this study is to design a cancer invasion model based on an interaction between cancer cells and cancer-associated fibroblasts (CAF) aggregates. The strength of this study is to incorporate gelatin hydrogel microspheres (GM) containing pifithrin-α (PFT) of a p53 inhibitor (GM-PFT) with the CAF aggregates. Incorporation of GM-PFT allowed CAF aggregates to enhance the alpha-smooth muscle actin expression level at a high concentration of PFT.

Influence of shaking culture on the biological functions of cell aggregates incorporating gelatin hydrogel microspheres.

The objective of this study is to investigate the influence of shaking culture on the biological functions of cell aggregates incorporating gelatin hydrogel microspheres in terms of the microspheres/cells ratio. The mixture of MC3T3-E1 cells and the microspheres was cultured in the U-bottomed wells of 96-well plate pre-coated with poly (vinyl alcohol) (PVA) to form cell aggregates incorporating microspheres. When incubated in the static or shaking culture, the size of cell aggregates increased with amounts of gelatin hydrogel microspheres but was similar between the two cultures.