label: url

en: Three-dimensional cell-culture systems using nanofibrillated bacterial cellulose restores drug metabolism activity in HepG2 hepatocellular carcinoma cells

en: Three-dimensional (3D) culture more faithfully reproducesin vivo-like cell interactions and functions than conventional two-dimensional (2D) monolayers. Although HepG2 cells are widely used in drug discovery, their 2D cultures exhibit low expression of drug-metabolizing enzymes such as cytochrome P450s (CYPs), limiting utility for toxicity and pharmacokinetic studies. Nano-fibrillated bacterial cellulose (NFBC) is a unique biomaterial that features exceptional homogeneity, high purity, and excellent biocompatibility. We recently employed two NFBC-based 3D culture systems: the Suspension and the OnGel methods. However, the capacity of NFBC to improve hepatocyte-specific functions has yet to be systematically explored. In this study, we aimed to establish a 3D culture platform for HepG2 cells using NFBC to restore hepatic functionality, and drug-metabolizing activity in particular, via comparison with conventional 2D monolayers. Both of these 3D culture systems produced viable HepG2 spheroids with good proliferation. Exploratory microarray profiling suggested broad upregulation of multiple absorption, distribution, metabolism and excretion (ADME) genes in the HepG2 spheroids. Among these, the enzyme Cytochrome P450 3A4 (CYP3A4) showed a significant increase in protein expression and in enzymatic activity in the HepG2 spheroids, which was functionally confirmed by acetaminophen (APAP) toxicity via its bioactivation into toxic metabolite. In addition, the HepG2 spheroids displayed reduced sensitivity to the anticancer drug doxorubicin compared to 2D monolayer. Collectively, these findings demonstrate that NFBC-based 3D culture systems effectively restore liver-specific functions in HepG2 cells, which results in HepG2 spheroids with metabolic competence and physiologically relevant drug responses, and could offer a promising tool for high-throughputin vitrodrug screening.

en: Biomedical Materials

ja: Biomedical Materials


en: Using PEGylated antigen-expressing extracellular vesicles to accomplish splenic B cell-targeted antigen delivery for induction of antibodies against SARS-CoV-2 spike protein

en: Extracellular vesicles are attracting attention as delivery vehicles for vaccines due to the inherent capacity of these cellular nanoparticles to preserve the structure and antigenicity of membrane antigens, which allows them to elicit immune responses. This intrinsic characteristic addresses the challenges associated with traditional antigen-containing formulations in maintaining antigen integrity while achieving high levels of loading efficiency. In this study, extracellular vesicles expressing antigens on their surface were utilized as potential antigen-delivery vehicles in a two-step intravenous (i.v.) immunization method, which amounts to the sequential injections of empty PEGylated liposomes (PEG-Lip) followed by PEGylated extracellular vesicles within a prescribed interval. To obtain SARS-CoV-2 spike protein-expressing extracellular vesicles (Exo-S1), a plasmid encoding SARS-CoV-2 Spike S1, primarily comprised of N-terminal domain (NTD) and receptor-binding domain (RBD), was transfected into murine melanoma cancer (B16BL6) cells. The Exo-S1 vesicles were PEGylated via the post-insertion method. Mice were immunized three times, with two-week intervals, with sequential injections of empty PEG-Lip followed by PEGylated Exo-S1 in 3-day intervals. Under our two-step immunization method, we observed the spleen accumulation of injected PEGylated extracellular vesicles, most likely in the marginal zone. After immunization, the mice showed high serum levels of IgG to whole spike S1 and spike RBD. The induced anti-SARS-CoV-2 spike IgG inhibited the interaction of spike RBD to angiotensin-converting enzyme 2 (ACE2), which controls viral infection. PEGylated antigen-expressing extracellular vesicles achieved efficient antigen delivery and effective immune responses under our two-step i.v. immunization method, which could be adopted to prevent the spread of infectious diseases such as COVID-19.

en: Journal of Pharmaceutical Sciences

ja: Journal of Pharmaceutical Sciences


en: Application of bacterial-derived long cellulose nanofiber to suspension culture of mammalian cells as a shear protectant

en: International Journal of Biological Macromolecules


en: Humoral immune response against SARS-CoV-2 and polyethylene glycol elicited by anti-SARS-CoV-2 mRNA vaccine, and effect of pre-existing anti-polyethylene glycol antibody in patients with hematological and autoimmune diseases.

en: The effects of vaccination are modified by hematological and autoimmune diseases and/or treatment. Anti-SARS-CoV-2 mRNA vaccine contains polyethylene glycol (PEG), it is largely unknown whether PEG influences the effects of vaccination or induces a humoral response. This study examined whether anti-PEG antibodies before vaccination (pre-existing) influenced the acquisition of SARS-CoV-2 antibodies and evaluated the relationship between the development of anti-SARS-CoV-2 antibodies and anti-PEG antibodies after SARS-CoV-2 vaccination in hematological and autoimmune diseases. Anti-SARS-CoV-2 antibody IgG, anti-PEG IgG, and IgM titers were evaluated in patients with hematological and autoimmune diseases after the second dose of BNT162B2. Anti-PEG IgG and IgM titers were also measured before vaccination to examine changes after vaccination and the relationship with vaccine efficacy. In patients with hematological (n = 182) and autoimmune diseases (n = 96), anti-SARS-CoV-2 and anti-PEG antibody titers were evaluated after a median of 33 days from 2nd vaccination. The median anti-SARS-CoV-2 antibody titers were 1901 AU/mL and 3832 AU/mL in patients with hematological and autoimmune disease, respectively. Multiple regression analysis showed that age and days from 2nd vaccination were negatively associated with anti-SARS-CoV-2 antibody titers. Anti-CD20 antibody treatment was negatively correlated with anti-SARS-CoV-2 antibody titers in hematological disease, and C-reactive protein (CRP) was positively correlated with anti-SARS-CoV-2 antibody titers in autoimmune disease. Baseline anti-PEG antibody titers were significantly higher in patients with autoimmune disease but were not correlated with anti-SARS-CoV-2 antibody titers. Patients with increased anti-PEG IgG acquired higher anti-SARS-CoV-2 antibody titers in patients with autoimmune disease. Anti-SARS-CoV-2 antibody acquisition was suboptimal in patients with hematological disease, but both anti-SARS-CoV-2 antibody and anti-PEG IgG were acquired in patients with autoimmune disease, reflecting robust humoral immune response. Pre-existing anti-PEG antibody titers did not affect anti-SARS-CoV-2 antibody acquisition.

en: Heliyon

ja: Heliyon


en: Impact of anti-PEG IgM induced via the topical application of a cosmetic product containing PEG derivatives on the antitumor effects of PEGylated liposomal antitumor drug formulations in mice

en: Poly(ethylene glycol) (PEG) is used in many common products, such as cosmetics. PEG, however, is also used to covalently conjugate drug molecules, proteins, or nanocarriers, which is termed PEGylation, to serve as a shield against the natural immune system of the human body. Repeated administration of some PEGylated products, however, is known to induce anti-PEG antibodies. In addition, preexisting anti-PEG antibodies are now being detected in healthy individuals who have never received PEGylated therapeutics. Both treatment-induced and preexisting anti-PEG antibodies alter the pharmacokinetic properties, which can result in a subsequent reduction in the therapeutic efficacy of administered PEGylated therapeutics through the so-called accelerated blood clearance (ABC) phenomenon. Moreover, these anti-PEG antibodies are widely reported to be related to severe hypersensitivity reactions following the administration of PEGylated therapeutics, including COVID-19 vaccines. We recently reported that the topical application of a cosmetic product containing PEG derivatives induced anti-PEG immunoglobulin M (IgM) in a mouse model. Our finding indicates that the PEG derivatives in cosmetic products could be a major cause of the preexistence of anti-PEG antibodies in healthy individuals. In this study, therefore, the pharmacokinetics and therapeutic effects of Doxil (doxorubicin hydrochloride-loaded PEGylated liposomes) and oxaliplatin-loaded PEGylated liposomes (Liposomal l-OHP) were studied in mice. The anti-PEG IgM antibodies induced by the topical application of cosmetic products obviously accelerated the blood clearance of both PEGylated liposomal formulations. Moreover, in C26 tumor-bearing mice, the tumor growth suppressive effects of both Doxil and Liposomal l-OHP were significantly attenuated in the presence of anti-PEG IgM antibodies induced by the topical application of cosmetic products. These results confirm that the topical application of a cosmetic product containing PEG derivatives could produce preexisting anti-PEG antibodies that then affect the therapeutic efficacy of subsequent doses of PEGylated therapeutics.

en: Molecular Pharmaceutics

ja: Molecular Pharmaceutics


en: Peritoneal B Cells Play a Role in The Production of Anti-Polyethylene Glycol (PEG) IgM Against Intravenously Injected siRNA-PEGylated Liposome Complexes

en: Biological & Pharmaceutical Bulletin

ja: Biological & Pharmaceutical Bulletin


en: マクロゴール4000の関連する全身性紅斑を呈した女児例

ja: マクロゴール4000の関連する全身性紅斑を呈した女児例

en: Pediatrics of Japan

ja: 小児科


en: Anti-PEG IgM production induced by PEGylated liposomes as a function of administration route

en: Modifying the surface of nanoparticles with polyethylene glycol (PEG) is a commonly used approach for improving the in vitro stability of nanoparticles such as liposomes and increasing their circulation half-lives. We have demonstrated that, in certain conditions, an intravenous (i.v.) injection of PEGylated liposomes (PEG-Lip) induced anti-PEG IgM antibodies, which led to rapid clearance of second doses in mice. SARS-CoV-2 vaccines, composed of mRNA-containing PEGylated lipid nanoparticles, have been widely administered as intramuscular (i.m.) injections, so it is important to determine if PEGylated formulations can induce anti-PEG antibodies. If the favorable properties that PEGylation imparts to therapeutic nanoparticles are to be widely applicable this should apply to various routes of administration. However, there are few reports on the effect of different administration routes on the in vivo production of anti-PEG IgM. In this study, we investigated anti-PEG IgM production in mice following i.m., intraperitoneal (i.p.) and subcutaneous (s.c.) administration of PEG-Lip. PEG-Lip appeared to induce anti-PEG IgM by all the tested routes of administration, although the lipid dose causing maximum responses varied. Splenectomy attenuated the anti-PEG IgM production for all routes of administration, suggesting that splenic immune cells may have contributed to anti-PEG IgM production. Interestingly, in vitro experiments indicated that not only splenic cells but also cells in the peritoneal cavity induced anti-PEG IgM following incubation with PEG-Lip. These observations confirm previous experiments that have shown that measurable amounts of PEG-Lip administered i.p., i.m. or s.c. are absorbed to some extent into the blood circulation, where they can be distributed to the spleen and/or peritoneal cavity, and are recognized by B cells, triggering anti-PEG IgM production. The results obtained in this study have important implications for developing efficient PEGylated nanoparticular delivery system.

en: Journal of Controlled Release

ja: Journal of Controlled Release


en: A maleimide-terminally modified PEGylated liposome induced the accelerated blood clearance independent of the production of anti-PEG IgM antibodies


en: The therapeutic effect of HSA dimer-doxorubicin complex against human pancreatic tumour

en: Pharmaceutics

ja: Pharmaceutics


en: Neutralization of acidic tumor microenvironment (TME) with daily oral dosing of sodium potassium citrate (K/Na Citrate) increases therapeutic effect of anti-cancer agent in pancreatic cancer xenograft mice model