Hideki Narumi

Hemostatic effects of polymerized albumin particles bearing rGPIa/IIa in thrombocytopenic mice

The recombinant fragment of the platelet membrane glycoprotein Ia/IIa (rGPIa/IIa) was conjugated to the polymerized albumin particles (polyAlb) with the average diameter of 180 nm. The intravenous administration of rGPIa/IIa-polyAlb to thrombocytopenic mice ([platelet] = 2.1+/-0.3 x 10(5) particles/ microL) with three doses of ca. 2.4 x 10(10), 7.2 x 10(10), and 2.4 x 10(11)particles/kg, respectively, significantly reduced their bleeding time to 426+/-71, 378+/-101, and 337+/-46 s, respectively, whereas that of the control groups (PBS) was 730+/-198 s. The injection of rGPIa/IIa-polyAlb (2.4 x 10(11)particles/kg) was approximately equal to the effect of the injection of the mouse platelets at a dose of 2.0 x 10(10) particles/kg. It was confirmed that rGPIa/IIa-polyAlb had a recognition ability against collagen and could contribute to the hemostasis in the thrombocytopenic mice as a platelet substitute.

Anti-allergic potential of oligomannose-coated liposome-entrapped Cry j 1 as immunotherapy for Japanese cedar pollinosis in mice.

Administration of oligomannose-coated liposomes (OMLs) in mice can induce Th1 immune responses against antigens entrapped in the OMLs. In the present study, we investigated the anti-allergic effect of treatment with oligomannose-coated liposomes (OMLs) with entrapped Cry j 1, a major allergen of Japanese cedar pollen (Cry j 1/OMLs), in Balb/c mice sensitized with Cry j 1. Pretreatment of unsensitized mice with Cry j 1/OMLs repressed the elevation of total and allergen-specific IgE levels in sera elicited in response to subsequent sensitization with Cry j 1. Cry j 1-specific IgG1 in sera also decreased in Cry j 1/OML-treated mice, while the levels of Cry j 1-specific IgG2a in these mice significantly increased after sensitization with Cry j 1. In addition, Cry j 1/OML-treated mice showed high IFN-gamma production from spleen cells and low IL-4/IFN-gamma and IL-5/IFN-gamma ratios in response to in vitro stimulation with Cry j 1. These results indicate that allergen-specific Th1 immune responses predominate over Th2 responses and control IgE elevation in Cry j 1/OML-treated mice. The anti-allergic effect of Cry j 1/OML determined by suppression of serum IgE levels was also observed in Cry j 1-presensitized mice after challenge with antigen. Thus, Cry j 1/OMLs may be useful for immunotherapeutic control of allergic reactions to Japanese cedar pollinosis.

Novel pegylated interferon-β as strong suppressor of the malignant ascites in a peritoneal metastasis model of human cancer

Malignant ascites manifests as an end‐stage event during the progression of a number of cancers and lacks a generally accepted standard therapy. Interferon‐β (IFN‐β) has been used to treat several cancer indications; however, little is known about the efficacy of IFN‐β on malignant ascites. In the present study, we report on the development of a novel, engineered form of human and murine IFN‐β, each conjugated with a polyethylene glycol molecule (PEG‐hIFN‐β and PEG‐mIFN‐β, respectively). We provide evidence that these IFN‐β molecules retain anti‐viral potency comparable to unmodified IFN‐β in vitro and manifested improved pharmacokinetics in vivo. Interestingly, PEG‐mIFN‐β significantly inhibited the accumulation of ascites fluid and vascular permeability of the peritoneal membrane in models of ovarian cancer and gastric cancer cell xenograft mice. We further show that PEG‐hIFN‐β directly suppresses VEGF165‐induced hyperpermeability in a monolayer of human vascular endothelial cells and that PEG‐mIFN‐β enhanced gene expression for a number of cell adhesion related molecules in mouse vascular endothelial cells. Taken together, these findings unveil a hitherto unrecognized potential of IFN‐β in maintaining vascular integrity, and provide proof‐of‐mechanism for a novel and long‐acting pegylated hIFN‐β for the therapeutic treatment of malignant ascites.

The combination of type I interferon and ribavirin has an inhibitory effect on mouse hepatitis virus infection

Aim:  To determine the differences in efficacy between therapy using IFN‐β and ribavirin, and using IFN‐α and ribavirin.

Development of a Novel Site-Specific Pegylated Interferon Beta for Antiviral Therapy of Chronic Hepatitis B Virus

ABSTRACT Although nucleot(s)ide analogues and pegylated interferon alpha 2a (PEG-IFN-α2a) can suppress hepatitis B virus (HBV) replication, it is difficult to achieve complete HBV elimination from hepatocytes. A novel site-specific pegylated recombinant human IFN-β (TRK-560) was recently developed. In the present study, we evaluated the antiviral effects of TRK-560 on HBV replication in vitro and in vivo. In vitro and in vivo HBV replication models were treated with antivirals including TRK-560, and changes in HBV markers were evaluated. To analyze antiviral mechanisms, cDNA microarray analysis and an enzyme-linked immunoassay (ELISA) were performed. TRK-560 significantly suppressed the production of intracellular HBV replication intermediates and extracellular HBV surface antigen (HBsAg) (P < 0.001 and P < 0.001, respectively), and the antiviral effects of TRK-560 were enhanced in combination with nucleot(s)ide analogues, such as entecavir and tenofovir disoproxil fumarate. The reduction in HBV DNA levels by TRK-560 treatment was significantly higher than that by PEG-IFN-α2a treatment both in vitro and in vivo (P = 0.004 and P = 0.046, respectively), and intracellular HBV covalently closed circular DNA (cccDNA) reduction by TRK-560 treatment was also significantly higher than that by PEG-IFN-α2a treatment in vivo (P = 0.0495). cDNA microarrays and ELISA for CXCL10 production revealed significant differences between TRK-560 and PEG-IFN-α2a in the induction potency of interferon-stimulated genes. TRK-560 shows a stronger antiviral potency via higher induction of interferon-stimulated genes and stronger stimulation of immune cell chemotaxis than PEG-IFN-α2a. As HBsAg loss and HBV cccDNA eradication are important clinical goals, these results suggest a potential role for TRK-560 in the development of more effective treatment for chronic hepatitis B infection.