Publications by authors named "Hidemi Takahashi"

Reports have described the excellent efficacies of new immunotherapeutic strategies, such as monoclonal antibody (mAb) therapies, in multiple myeloma (MM) patients. Signaling lymphocytic activation molecule family (SLAMF) molecules are expressed strongly on normal lymphocytes and plasma cells from MM patients. The anti-SLAMF7 mAb elotuzumab (ELO) has been approved for the treatment of relapsed/refractory MM (RRMM).

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Problem: Septate uterus is associated with spontaneous abortion. Surgical intervention of the uterine septa (US) is frequently performed following spontaneous abortion; however, immunological mechanisms for spontaneous abortion in patients with septate uterus remain completely unknown.

Method Of Study: A total of 12 women with septate uterus who underwent hysteroscopic metroplasty and 10 women with uterine leiomyoma who underwent total hysterectomy were enrolled as the experimental and control groups, respectively.

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Although the Japanese traditional herbal medicine (Kampo), Juzentaihoto (JTT), has been reported to have antitumor effects in several tumor models, its role in tumor immunology remains controversial. In the present study, we tested whether oral administration of JTT enhances antitumor immunity in CD1d mice, in which immunosuppression was partially relieved due to the lack of NKT cells. In a subcutaneous murine syngeneic CT26 colorectal tumor model, JTT had no impact on tumor growth in wild type (WT) BALB/c mice.

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Immunotherapy for cancer cells induced by interfering with PD-1/PD-L1 engagement via check-point blockades was initiated by tumour-specific PD-1 CD8 cytotoxic T lymphocytes (CTLs) within a tumour mass and eliminate the tumour. Here, we used C57BL/6 (B6) mice implanted with the syngeneic hepatoma cell line Hepa1-6-1, and confirmed that the dendritic cells (DCs) within Hepa1-6-1 tumour mass were tolerogenic with downmodulated co-stimulatory molecules by tumour-derived factors. Although Hepa1-6-1 cells did not prime tumour-specific CTLs within the tumour, specific CTLs primed in the regional lymph nodes seemed to be invaded into the tumour mass.

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The main effectors in tumor control are the class I MHC molecule-restricted CD8 cytotoxic T lymphocytes (CTLs). Tumor-specific CTL induction can be regulated by dendritic cells (DCs) expressing both tumor-derived epitopes and co-stimulatory molecules. Immunosuppressive tolerogenic DCs, having down-regulated co-stimulatory molecules, are seen within the tumor mass and can suppress tumor-specific CTL induction.

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We established transfectants expressing T cell receptors (TCRs) either for Vγ1 and Vδ1 (1C116) or for Vγ2 and Vδ2 (2C21) using the TCR-deficient Jurkat T cell line J.RT3-T3.5.

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Helicobacter pylori (H. pylori) urease is a key protein for persistent infection of the bacteria in the stomach. Although H.

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Because human epidermal growth factor-like receptor (HER) 2 is expressed on the surface of human pancreatic carcinoma cells to varying degrees, trastuzumab, an anti-HER2 monoclonal antibody (mAb), is expected to exert antibody-dependent, natural killer (NK) cell-mediated cytotoxicity (ADCC) against the cells. However, some reports found that the effect of trastuzumab against human pancreatic carcinoma cells was limited because most express only limited HER2. We examined whether anti-CD137 stimulating mAb could enhance trastuzumab-mediated ADCC against Panc-1, a human pancreatic cancer cell line with low HER2 expression, in vitro.

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Human mucosal tissues and skin contain two distinct types of dendritic cell (DC) subsets, epidermal Langerhans cells (LCs) and dermal DCs, which can be distinguished by the expression of C-type lectin receptors, Langerin and DC-SIGN, respectively. Although peripheral blood monocytes differentiate into these distinct subsets, monocyte-derived LCs (moLCs) induced by coculture with GM-CSF, IL-4, and TGF-β1 coexpress both Langerin and DC-SIGN, suggesting that the environmental cues remain unclear. In this study, we show that LC differentiation is TGF-β1 dependent and that cofactors such as IL-4 and TNF-α promote TGF-β1-dependent LC differentiation into LangerinDC-SIGN moLCs but continuous exposure to IL-4 blocks differentiation.

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Fetomaternal immune tolerance is required to prevent fetal rejection during pregnancy; simultaneously, the maternal immune system must also protect the fetus from harmful endogenous and exogenous antigens, including those associated with viral and bacterial infections. Therefore, a delicate immune balance is critical for the maintenance of a successful pregnancy, while disruption of this balance can induce complications such as implantation failure, miscarriage, preterm birth/labor, preeclampsia and fetal growth restriction. While the adaptive immune system is critical for the development of tolerance, this review summarizes evidence that modulation of the innate immunity is also essential for achieving this delicate balance between tolerance and protection.

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Cholera toxin (CT) is a potent mucosal adjuvant and oral administration of ovalbumin (OVA) antigens plus CT induces OVA-specific CD8 cytotoxic T lymphocytes (CTLs) and IgA production in intestinal mucosa. However, the mechanisms of induction of these immune responses remain unknown. Intestinal OVA-specific CD8 CTLs were not induced by oral administration of the CT active (CTA) or CT binding (CTB) subunit as an adjuvant and CD11c DCs were involved in cross-priming of intestinal CTLs.

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Unexpected fetal loss is one of the common complications of pregnancy; however, the pathogenesis of many miscarriages, particularly those not associated with infections, is unknown. We previously found that activated DEC-205 dendritic cells (DCs) and NK1.1 invariant natural killer T (iNKT) cells are recruited into the myometrium of mice when miscarriage is induced by the intraperitoneal administration of α-galactosylceramide (α-GalCer).

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T-cell immunoglobulin mucin-3 (Tim-3), an inhibitory immune checkpoint receptor, is highly expressed on acute myeloid leukemia cells and its ligand galectin-9 is reported to drive leukemic progression by binding with Tim-3. However, it remains unclear whether the Tim-3-galectin-9 pathway is associated with the pathophysiology of myelodysplastic syndromes (MDS). Thus, we investigated the expression and function of Tim-3 and the clinical impact of its ligand galectin-9 in MDS.

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Although Japanese traditional herbal medicine (Kampo) has been widely applied to the treatment of various diseases, including cancer, their mechanisms of action have not yet been elucidated in detail, particularly regarding their role in tumor immunology. The present study investigated the antitumor effects of the Japanese Kampo medicine, ninjin'yoeito (NYT; Ren-Shen-Yang-Rong-Tang in Chinese), which was orally administered with or without an irradiated tumor cell vaccine to a subcutaneous CT26 colon carcinoma tumor model. The irradiated tumor cell vaccine in a prophylactic setting significantly delayed tumor growth in mice fed a control diet, whereas a diet containing NYT alone did not exert any antitumor effects .

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 Aquatic bacteria were isolated from the hands of working staffs by an adapted culture protocol. When the sample solution obtained by the" glove juice method" was incubated for 3 days at room temperature, viable cell counts increased up to 10-fold, and the majority of the isolated colonies were shown to be Gram-negative aquatic bacteria, which carry the risk of contaminating water. Using R2A medium, coagulase-negative staphylococci were the dominant microbes immediately after recovery from the hands.

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Cancer immunity is mediated through the effective priming and activation of tumour-specific class I MHC molecule-restricted CD8 cytotoxic T lymphocytes (CTLs). DEC-205 dendritic cells (DCs) can cross-present the epitope(s) of captured tumour antigens associated with class I MHC molecules alongside co-stimulatory molecules to prime and activate tumour-specific CD8 CTLs. Immunosuppressive tolerogenic DCs with reduced co-stimulatory molecules may be a cause of impaired CTL induction.

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Problem: Acute chorioamnionitis (aCAM) is an important cause of pre-term birth. However, little is known about the pathogenesis of late pre-term birth without aCAM that was the most common category of pre-term birth. Here we analyze the kinetics of immune cells obtained from the decidua of women with late pre-term births with and without aCAM.

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Langerhans cells (LCs), a subset of dendritic cells (DCs), reside in body surface presenting antigens from various pathogens and activate immune system after migrating to vicinal lymph nodes. We recently demonstrated that the E-cadherin interaction allowed peripheral blood (PB) CD14 cells to differentiate into LC-like cells that closely resemble primary LCs. Here, with a combination of GM-CSF, TGF-β, and TNF-α, we induced LC-like cells from umbilical cord blood (UCB)derived CD34 cells and compared them with those induced from PB CD14 cells.

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Innate immunity, which is unable to discriminate self from allo-antigens, is thought to be important players in the induction of miscarriages. Here, we show that the administration of IL-12 to syngeneic-mated C57BL/6 mice on gestation day 7.5 (Gd 7.

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Background: Two major distinct subsets of dendritic cells (DCs) are arranged to regulate immune responses: DEC-205+ DCs drive Th1 polarization and 33D1+ DCs establish Th2 dominancy. Th1 polarization can be achieved either by depletion of 33D1+ DCs with a 33D1-specific monoclonal antibody (mAb) or by activation of DEC-205+ DCs via intraperitoneal injection of α-galactosylceramide (α-GalCer). We studied the effect of 33D1+ DC depletion or DEC-205+ DC activation in vivo using an established mouse model of allergic rhinitis (AR).

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Dendritic cells (DCs) play a major role in in vivo pathogenesis of HIV-1 infection. Therefore, DCs may provide a promising strategy to control and eventually overcome the fatal infection. Especially, immature DCs express all CD1s, the non-MHC lipid antigen -presenting molecules, and HIV-1 Nef down-regulates CD1 expression besides MHC.

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The mechanism of action of ribavirin (RBV) as an immunomodulatory and antiviral agent and its clinical significance in the future treatment of patients with hepatitis C virus (HCV) infection are reviewed. RBV up-regulates type 1 and/or 2 cytokines to modulate the T helper (Th) 1/2 cell balance to Th1 dominance. Examination of co-stimulatory signaling indicated that RBV down-modulates inducible co-stimulator on Th cells, which contributes to differentiating naïve Th cells into Th2 cells while reducing their interleukin-10 production.

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The major effector cells for cellular adaptive immunity are CD8(+) cytotoxic T lymphocytes (CTLs), which can recognize and kill virus-infected cells and tumor cells. Although CTLs exhibit strong cytolytic activity against target cells in vitro, a number of studies have demonstrated that their function is often impaired within tumors. Nevertheless, CTLs can regain their cytotoxic ability after escaping from the tumor environment, suggesting that the milieu created by tumors may affect the function of CTLs.

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We have previously established a human glioblastoma cell line persistently infected with mutant measles virus (MV), and found increased functions of mitochondria in MV persistently infected cells compared with uninfected or acutely infected cells. Moreover, impairment of mitochondria functions induced a breakdown of persistent infection, which suggested that mitochondria might play an important role in the maintenance of persistent infection and loss or functional alterations of mitochondria might be a candidate for possible intervention in persistent infection. In this study we examined the effect of dichloroacetate (DCA), which is known to increase pyruvate oxidation, on mitochondrial functions in MV persistently infected cells.

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