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Biomedical subjects

Miwako Narita

Publications and source records attributed to Miwako Narita.

15 recordsLinked to original sources
PubMed2005

Clinical evaluation of dendritic cell vaccination for patients with recurrent glioma: results of a clinical phase I/II trial.

PURPOSE: To investigate the safety and the immunologic and clinical responses of dendritic cell therapy for patients with recurrent malignant glioma. EXPERIMENTAL DESIGN: Twenty-four patients with recurrent malignant glioma (6 grade 3 and 18 grade 4 patients) were evaluated in a phase I/II clinical study of dendritic cell therapy. All patients were resistant to the standard maximum therapy. The patient's peripheral blood dendritic cells were generated with granulocyte macrophage colony-stimulating factor, plus interleukin 4 with or without OK-432, and pulsed with an autologous tumor lysate. Dendritic cells were injected intradermally, or both intratumorally and intradermally every 3 weeks. RESULTS: The protocols were well tolerated with only local redness and swelling at the injection site in several cases. Clinical responses were as follows: 1 patient with partial response, 3 patients with minor response, 10 patients with stable disease, and 10 patients with progressive disease. The patients whose dendritic cells were matured with OK-432 had longer survival times than the dendritic cells from patients without OK-432 maturation. The patients with both intratumoral and intradermal administrations had a longer survival time than the patients with intradermal administration only. Increased ELISPOT and delayed-type hypersensitivity responses after vaccination could provide good laboratory markers to predict the clinical outcome of patients receiving dendritic cell vaccination. The overall survival of patients with grade 4 glioma was 480 days, which was significantly better than that in the control group. CONCLUSIONS: This study showed the safety and clinical response of autologous tumor lysate-pulsed dendritic cell therapy for patients with malignant glioma. Dendritic cell therapy is recommended for further clinical studies in malignant glioma patients.

Adult↗
PubMed2005

Persistence of various chromosomal aberrations in recipient cells during complete remission after bone marrow transplantation followed by graft rejection.

A 16-year-old boy in a second remission of acute lymphoblastic leukemia (ALL) had undergone transplantation of bone marrow from an unrelated donor. The conditioning regimen consisted of high-dose cytarabine, etoposide and 12 Gy of total-body irradiation. Although the donor marrow was rejected, hematopoiesis by the recipient himself recovered and he has remained in complete remission for more than 8 years after stem cell transplantation (SCT). Bone marrow karyotype analysis 1 month after SCT showed random chromosomal aberrations. Although complete remission was maintained, various chromosomal aberrations were detected in marrow cells, and in peripheral blood cells under phytohemagglutinin stimulation over 8 years. Moreover, a clone including del(20)(q11) appeared in marrow cells 7 months after SCT and thereafter was also detected 5 years later in the peripheral blood. This persistence of various chromosomal aberrations and a stable clone without evolution to myelodysplastic syndrome or leukemia support the multi step theory of leukemogenesis.

Adolescent↗
PubMed2004

Sensitive measurement of fragmented red cell population using flow cytometry, and its application for estimating thrombotic microangiopathy after stem cell transplantation.

BACKGROUND: Thrombotic microangiopathy (TMA) is one of the lethal complications after hematopoietic stem cell transplantation (SCT). The levels of fragmented red cells (FRCs), thrombomodulin (TM), and factor VIII-related antigen in the blood are the most important markers for estimating TMA. However, the FRC level has been measured by using microscopy and the naked eye; therefore, an improvement in technology to objectively count FRC is necessary. METHODS: We established a novel technique to sensitively measure FRC as glycophorin A dull-positive small particles using a flow cytometer and estimated its reliability in patients treated with SCT. The blood level of FRC was compared with other clinical data in 257 blood samples in 16 clinical courses after SCT of 15 patients. RESULTS: Sorted glycophorin A dull-positive small particles morphologically showed FRC. Measured FRC percentage had a weak correlation with serum levels of lactate dehydrogenase (LDH) and total bilirubin but not with TM level, whereas TM showed a weak correlation with the levels of aspartate aminotransferase and LDH. In a patient with fulminant TMA, decrement of the FRC level led to improvement in liver parameters after treatment, presumably due to the rapid clearance of FRC, and increased simultaneously with the levels of LDH and bilirubin by the TMA recurrence. CONCLUSIONS: Levels of FRC percentage and TM were independent parameters of TMA. This novel technique may be used as a standard methodology in diagnosing TMA.

Adolescent↗
PubMed2004

Simultaneous expression of CD13, CD22 and CD25 is related to the expression of Fc epsilon R1 in non-lymphoid leukemia.

Like CD19 or CD56, CD22 in non-lymphoid leukemia has been considered an aberrantly expressed antigen. CD22 had been believed to be restricted to B lymphoid, however, it was also found to be expressed in human basophils. Mature basophils are unique granulocytes expressing CD13, CD22 and CD25. To estimate whether the expression of CD22 in non-lymphoid leukemia is aberrant or related to basophilic character, we analyzed 108 patients with primary and secondary leukemia. Among non-lymphoid leukemias, surface CD22 expression was more frequently observed in peroxidase-negative AML and secondary leukemia, and was usually observed simultaneously with CD13 and CD25. Samples obtained from 17 cases were further analyzed, and all the Fc epsilon R1-positive cases were observed in peroxidase-negative AML and secondary non-lymphoid leukemia, and mostly expressed CD13, CD22 and CD25. Therefore, surface CD22 expression in non-lymphoid leukemia was thought to relate to basophilic phenotype in some cases. Like CD22, some of the so-called aberrantly expressed antigens may not actually be aberrant, but are expressed in a stage of differentiation and maturation of progenitors. Moreover, CD22 may be one of target molecules for treatment of CD22-positive, poorly prognostic leukemia.

Adolescent↗
PubMed2004

Induction of T cell anergy by the treatment with IL-10-treated dendritic cells.

In order to apply for reducing graft versus host disease in allogeneic stem cell transplantation, the study concerning the induction of specific T cell anergy was designed. Normal allogeneic lymphocytes, which were co-cultured with IL-10-treated immature dendritic cells in the first mixed leukocyte culture (MLC), were cultured with mature dendritic cells of the same origin as IL-10-treated immature dendritic cells in the second MLC. By co-culturing with IL-10-treated immature dendritic cells, the response of normal lymphocytes to mature dendritic cells cultured from the same individual as that of IL-10-treated dendritic cells was markedly reduced, compared with the lymphocytes cultured with non-treated dendritic cells or IL-10-treated dendritic cells from a third party individual. The present study demonstrated that antigen specific T cell anergy was generated by priming allogeneic lymphocytes with IL-10-treated immature dendritic cells. These data suggested the applicability of IL-10-treated recipient dendritic cells for the induction of recipient cell-specific donor T cell anergy in donor graft.

Clonal Anergy↗
PubMed2004

Human dendritic cells mediate anti-tumor activity against hematopoietic tumor cells without direct contact and Fas/FasL killing pathway.

During maturation, the capacity of dendritic cells (DCs) to uptake and process antigens becomes diminished while the expression of MHC molecules and costimulatory molecules is up-regulated. These phenotypic changes make DCs potent antigen presenting cells with the ability to initiate and modulate immune responses. Recent findings have shown that DCs can mediate direct cytotoxicity toward tumor cells. Here, we investigated the effect of monocyte derived DC (moDC) on hematopoietic tumor cells by assessing the uptake of [methyl-3H]thymidine (3H-TdR), JAM test (radiometric assay for DNA fragmentation) and 51Cr-release assay. We found that moDCs significantly inhibited the growth of 6 tumor cell lines and stimulated another 4 cell lines independently of the expression of Fas protein. MoDCs also inhibited the proliferation of tumor cells in transwell culture, including two cell lines that were driven to proliferate by direct contact with moDCs. Apoptosis, but not cytolysis, was detected in all the cell lines inhibited by moDCs. In contrast, no cytostatic or cytotoxic effect was detected on K562 cells (chronic myeloid leukemia) and BY94 cells (sporadic Burkitt's lymphoma). The inhibitory activity of moDCs on Fas-expressing tumor cells fully persisted after the neutralization of FasL. Accordingly, there was no detection of FasL protein or FasL mRNA expression in moDC. These results suggest that moDCs can mediate a direct anti-tumor activity against hematopoietic tumor cells through cytostasis in absence of contact or through apoptosis without triggering the Fas/FasL pathway.

Apoptosis↗
PubMed2003

The effects of STI571 on antigen presentation of dendritic cells generated from patients with chronic myelogenous leukemia.

Chronic myelogenous leukemia is caused by the acquisition of the reciprocal (9;22)(q34;q11) chromosomal translocation in hematopoietic stem cells. The fusion protein showed higher and aberrant tyrosine kinase activity. The inhibition of the tyrosine kinase activity of the protein represents a specific therapeutic strategy for bcr/abl-expressing leukemias. STI571 is a compound of the 2-phenylaminopyrimidine class that selectively inhibits the tyrosine kinase activity of the Abl protein tyrosine kinase. In this study, we evaluated the effects of STI571 on antigen presentation of dendritic cells generated from the patients with CML. The data showed that by the addition of STI571 the dendritic cells derived from CML clone showed an increased expression of CD1a, CD83, CD80 and CD86 by flow cytometry analysis and showed more intense abilities of allogeneic antigen presentation by mixed leukocyte culture, compared with the control cells without STI571. Our results suggested that STI571 not only has a direct cytotoxic effect on bcr-abl gene rearranged cells but also an indirect effect associated with increased anti-leukemic immunological function due to an intensified antigen presentation.

Antigen Presentation↗
PubMed2003

Fc epsilon RI and CD22 mRNA are expressed in early B-lineage and myeloid leukemia cell lines.

CD22, one of the important markers for diagnosing B-lineage acute leukemia, was expressed in mature basophil granulocytes. We then investigated the expression of CD22 and other B cell- and basophil-related molecules in 25 human acute leukemia cell lines to find the phenotype of the virtual common progenitor of B and myeloid lineage. Surface and cytoplasmic expressions of antigens were analyzed using a flow cytometer and an essential antibody panel used for diagnosing acute leukemia as well as cytokine receptors and basophil-related enzymes. Messenger RNA expression of Fc epsilon R1 and CD22 was also analyzed. Peroxidase-positive and -negative myeloid leukemias showed eosinophil- and basophil-type expression of enzymes, respectively. Early myeloid and B-lineage cells expressed basically similar combinations of cytokine receptors and various combinations of mRNA listed above, while T-lineage cells did not. The virtual common progenitor of B and myeloid lineage cells may be defined as immature cells simultaneously expressing B and basophil phenotypes.

Acute Disease↗
PubMed2003

Masked MLL gene rearrangement was disclosed in the clinical course and sequential development of chromosome abnormality in a patient with therapy related acute myelogenous leukemia.

Therapy related acute myelogenous leukemia in a 55-year-old Japanese woman is described. She had been treated for a diagnosis of non-Hodgkin's lymphoma 2 years before the onset of the secondary leukemia. She was diagnosed as AML (FAB: M2) with monosomy 7, and successfully treated by an intensive combination chemotherapy followed by an autologous peripheral blood stem cell transplantation. The disease relapsed shortly after the treatment, and the karyotype analysis revealed a complex abnormality accompanied with t(9;11)(p22;q23), however, monosomy 7 was absent. Southern blotting analysis was performed, and MLL rearrangement was evident in both the bone marrow samples obtained at that time and the cryopreserved marrow cells obtained at the onset of the disease. The bone marrow sample stored in a Carnoy solution at the onset was further analyzed, and three karyotype panels showing 45,XX, -7, t(9;11)(p22;q23) were found. Like this situation, a masked MLL rearrangement may have existed in some cases with hematopoietic malignancies, and appear to be disclosed in the clinical course.

Cell Transformation, Neoplastic↗
PubMed2003

A comparative study of the JAM test and 51Cr-release assay to assess the cytotoxicity of dendritic cells on hematopoietic tumor cells.

Dendritic cells (DCs) are potent antigen presenting cells and possess a direct anti-tumor cytotoxic ability. Nevertheless, the mechanism of anti-tumor cytotoxicity by DCs and the methods for its evaluation are not fully elucidated. In order to clarify this mechanism of cytotoxicity, we examined the ability of DCs 1) to suppress [3H] thymidine (3H-TdR) uptake by tumor cells; 2) to induce cytolysis on 51Cr-labeled tumor cells; 3) and to induce DNA fragmentation on 3H-TdR labeled tumor cells (JAM test). Cytolysis and DNA fragmentation are markers of necrotic and apoptotic mechanisms of cytotoxicity in vitro, respectively. DCs inhibited approximately 38.6% to 54.8% of the growth of B4D6, NB4, U937, and Daudi cells as evaluated by the uptake of 3H-TdR. However no cytolysis was verified by 51Cr-release assay. On the other hand, cytotoxicity rates found using the JAM test ranged from 3 to 81% depending on the cell line and the effector to target cell ratio. The discrepancy of cytotoxicity between 51Cr-release assay and the JAM test may be due to the phagocytosis of apoptotic tumor cells or the absorption of released 51Cr by DCs surrounding the target cells. In conclusion, the JAM test was more sensitive than the 4-h and the 10-h 51Cr-release assay to investigate cytotoxicity mediated by DCs toward hematopoietic tumor cell lines in vitro.

Antigens, CD↗
PubMed2003

Cytoplasmic expression of EGFP in dendritic cells transfected with in vitro transcribed mRNA or cellular total RNA extracted from EGFP expressing leukemia cells.

The present study was designed for identifying the protein synthesis in cytoplasm of dendritic cells transfected with in vitro transcribed mRNA and cellular total RNA extracted from tumor cells. Dendritic cells were generated from cord blood-CD34+ cells by culture with GM-CSF, SCF, and TNF-alpha, or from peripheral blood adherent cells or CD14+ cells by culture with GM-CSF and IL-4. Dendritic cells were transfected with in vitro transcribed EGFP mRNA or cellular total RNA, which was isolated from EGFP expressing K562, by electroporation using a square-wave pulse. Optimal in vitro transcribed EGFP mRNA transfection efficiency (>90%) was observed in a single electroporation of 1.75 kV/cm (electric field strength) with a pulse width of 250 micros. Although the intensity of EGFP expression in dendritic cells transfected with cellular total RNA was less compared with that in dendritic cells transfected with in vitro transcribed EGFP mRNA, a definite cytoplasmic synthesis of EGFP was demonstrated in dendritic cells transfected with cellular total RNA. The visual identification of cytoplasmic expression of cellular total RNA in dendritic cells revealed that electroporation of tumor cell-derived RNA could be a useful tool to load dendritic cells with tumor antigens for establishing an efficient dendritic cell-based tumor immunotherapy.

Dendritic Cells↗
PubMed2003

Dendritic cell-based glioma immunotherapy (review).

Despite advances in radiation and chemotherapy along with surgical resectioning, the prognosis of patients with malignant glioma is poor. Among the new treatments currently being investigated for malignant glioma, immunotherapy is theoretically very attractive, since it offers the potential for high tumor-specific cytotoxicity. There are increasing reports demonstrating that systemic immunotherapy using dendritic cells is capable of inducing an antiglioma response. Therefore, dendritic cell-based immunotherapy could be a new treatment modality for patients with glioma. In this review, we will discuss the implications of these findings for glioma therapy. A literature review of dendritic cell-based glioma immunotherapy was used to overview the dendritic cell in immunobiology, in the central nervous system and in tumor immunology, glioma-associated antigens, dendritic cell therapy in animal glioma model, dendritic cell therapy in clinical trials and future directions in dendritic cell therapy. Dendritic cell-based immunotherapy strategies appear promising as an approach to successfully induce an antitumor immune response and increase survival in patients with glioma. Dendritic cell therapy of glioma seems to be safe and without major side effects. Its efficacy should be further determined in randomized, controlled clinical trials. The development of methods for manipulating dendritic cells for the purpose of vaccination will enhance the clinical usefulness of these cells for biotherapy for malignant glioma.

Animals↗
PubMed2002

Generation of functional and mature dendritic cells from cord blood and bone marrow CD34+ cells by two-step culture combined with calcium ionophore treatment.

The object of this study is to explore a culture method to generate a large number of functional and mature dendritic cells (DC) from human CD34+ hematopoietic progenitor cells. In the present study, we used a two-step method combined with calcium ionophore to induce DC from cord blood (CB) or normal human bone marrow (BM) CD34+ progenitor cells. The two-step method consists of 10 days of first step culture for the expansion and proliferation of CD34+ hematopoietic progenitor cells in the presence of SCF, IL-3, IL-6, G-CSF, and 7--11 days of second step culture for the induction of DC in the presence of GM-CSF, IL-4 and TNF-alpha. By the two-step culture, total nucleated cells were increased 208+/-66 (+/-SD, n=13), or 94+/-29 (n=5)-fold in the culture of CB or BM cells, respectively, compared with the number of CD34+ cells at the time of starting culture. Out of the total nucleated cells, 23 +/-10.4% of cells in CB cell culture and 25 +/-5% of cells in the BM cell culture acquired DC characteristic phenotypes, which were marked expressions of CD1a, HLA-DR, co-stimulatory molecules such as CD80, CD40, and adhesion molecule such as CD58. In allogeneic mixed leukocyte reaction (MLR), two-step cultured cells showed potent allo-stimulatory capacity. With this two-step culture, the absolute number of CD1a+ cells that co-expressed HLA-DR, CD80, CD40 and CD58 was enhanced approximately 3 times in CB cell culture and 1.9 times in BM cell culture, compared with the commonly used one-step culture method for the generation of DC from CD34+ cells using SCF, GM-CSF and TNF-alpha. However, on these DC generated in the two-step culture, the expressions of co-stimulatory molecule CD86 and mature DC marker CD83 were not sufficient. By the treatment of two-step cultured cells with calcium ionophore agent (A23187), the expression of co-stimulatory molecules such as CD86 and CD80 (especially CD86) was up-regulated. Besides, the expression of mature DC marker CD83 was remarkably induced by treatment with A23187 for a short duration (24 h). Consistent with the up-regulation of surface molecules CD86, CD80 and CD83, the two-step cultured cells treated with A23187 also showed a stronger allo-stimulatory capacity compared with the cells without A23187 treatment. In conclusion, the present study demonstrated that the two-step culture method effectively improved the yield of CD1a+ DC generated from CD34+ cells, and the phenotypes and functions of these CD1a+ DC could be enhanced efficiently by treatment with a calcium ionophore agent.

Antigens, CD34↗