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Masayoshi Kobune

Publications and source records attributed to Masayoshi Kobune.

At least 19 recordsLinked to original sources

Ex vivo large-scale generation of human platelets from cord blood CD34+ cells.

In the present investigation, we generated platelets (PLTs) from cord blood (CB) CD34(+) cells using a three-phase culture system. We first cultured 500 CB CD34(+) cells on telomerase gene-transduced human stromal cells (hTERT stroma) in serum-free medium supplemented with stem cell factor (SCF), Flt-3/Flk-2 ligand (FL), and thrombopoietin (TPO) for 14 days. We then transferred the cells to hTERT stroma and cultured for another 14 days with fresh medium containing interleukin-11 (IL-11) in addition to the original cytokine cocktail. Subsequently, we cultured the cells in a liquid culture medium containing SCF, FL, TPO, and IL-11 for another 5 days to recover PLT fractions from the supernatant, which were then gel-filtered to purify the PLTs. The calculated yield of PLTs from 1.0 unit of CB (5 x 10(6) CD34(+) cells) was 1.26 x 10(11) - 1.68 x 10(11) PLTs. These numbers of PLTs are equivalent to 2.5-3.4 units of random donor-derived PLTs or 2/5-6/10 of single-apheresis PLTs. The CB-derived PLTs exhibited features quite similar to those from peripheral blood in morphology, as revealed by electron micrographs, and in function, as revealed by fibrinogen/ADP aggregation, with the appearance of P-selectin and activated glycoprotein IIb-IIIa antigens. Thus, this culture system may be applicable for large-scale generation of PLTs for future clinical use.

Antigens, CD34↗

Ex vivo expansion of G-CSF-mobilized peripheral blood CD133+ progenitor cells on coculture with human stromal cells.

OBJECTIVE: The pentaspan molecule CD133 has been shown to be a marker of more primitive hematopoietic progenitors in mobilized peripheral blood (PB). Our objective was to assess the efficacy of PB CD133(+) cells in our coculture system using human telomerized stromal (HTS) cells. METHODS: Five thousand PB CD133(+) cells or conventional cord blood (CB) CD34(+) cells were expanded with or without HTS cells in the presence or absence of stem cell factor, thrombopoietin, and Flk-2/Flt-3 ligand. RESULTS: The coculture was significantly superior in expanding PB clonogenic cells as compared with the stroma-free culture (CFU-C, 2 +/- 0 vs 111 +/- 15-fold of initial cell number, p < 0.01), and the fold increase of PB clonogenic cells was comparable to that for CB cells after two weeks of coculture (BFU-E, 54 +/- 3 vs 56 +/- 4-fold; CFU-GM, 156 +/- 26 vs 83 +/- 9-fold; CFU-Mix, 30 +/- 11 vs 80 +/- 36-fold). However, proliferation of CFU-Mk from PB on coculture with HTS cells was modest as compared with stroma-free culture. Concomitantly, multiple hematopoietic cells transmigrated below the stromal layer and formed cobblestone areas (CAs). The production of hematopoietic progenitor cells from CAs after coculture with PB was significantly lower than that seen in cells cocultured with CB for four weeks (CFU-Mix, 0 +/- 0 vs 9 +/- 5-fold on day 28, p < 0.01), although a similar number of CAs derived from PB and CB were observed. CONCLUSION: PB CD133(+) cells proliferated efficiently above the stromal layer, while the characteristics of PB CD133(+) cells underneath the human stromal layer were likely to be maintained, even after long-term hematopoietic-stromal interaction.

AC133 Antigen↗

[Enteropathy-type T-cell lymphoma with CD8 and CD56 expression].

A 54-year-old male presented at a previous hospital with abdominal pain, where the patient was diagnosed as having abdominal and retroperitoneal lymphadenopathies by CT scan, then, he was referred to our hospital for further examination. Upper gastrointestinal endoscopy showed a tumor formation in the second portion of the duodenum, and there were medium sized atypical lymphocytes in biopsy specimens of the tumor. Since the atypical lymphocytes in the biopsy specimens were positive for CD3, CD8, CD56 and CD103 by immunostain, and had a rearrangement of the T-cell receptor 7-chain, the patient was diagnosed as having enteropathy-type T-cell lymphoma (ETL). Although ETL usually occurs as a complication of celiac disease, malabsorption and anti-gliadin antibodies, which are normally present in celiac disease, were not observed in this patient.

CD3 Complex↗

[Peripheral T-cell lymphoma presenting with eosinophilia due to interleukin-5 produced by lymphoma cells].

A 72-year-old male was admitted to our hospital to determine the cause of neck lymphadenopathies. He was diagnosed pathologically by a lymph node biopsy as having peripheral T-cell lymphoma (PTCL). He also had developed eosinophilia and his serum concentration of Interleukin-5 (IL-5) was extremely high. Immunostaining of a resected lymph node revealed that there were lymphoma cells which were stained with anti-IL-5 antibody. After 2 courses of CHOP therapy, the lymphadenopathies and eosinophilia disappeared and the concentration of serum IL-5 was normalized. It was suggested that IL-5 produced by lymphoma cells had induced his eosinophilia.

Aged↗

Augmentation of antitumor effects of p53 gene therapy by combination with HDAC inhibitor.

We have previously shown that the HDAC inhibitors (HDACI) activate the p53 molecule through acetylation of 320 and 373 lysine residues, upregulate PIG3 and NOXA and induce apoptosis in cancer cells expressing wild and pseudo-wild type p53 genes (Terui T, et al. Cancer Res 2003; 63:8948-54). It has also been reported that expression of the Coxsackie adenovirus receptor and subsequent transfection efficiency of the adenovirus in cancer cells were enhanced by HDACI treatment. In this study, we extended these observations to explore the combination effect of adenoviral vector carrying wild type p53 (Ad-p53) gene therapy with a HDACI, sodium butyrate (SB), on xenografted human gastric cancer cells (KATO-III) and hepatocellular carcinoma cells (HuH7) in nude mice. We first confirmed an increased expression of Coxsackie adenovirus receptors with an associated increment of transgene (X-gal) expression by SB treatment in KATO-III cells. We then injected Ad-p53 into subcutaneous tumors of KATO-III and HuH7 combined with intraperitoneal administration of SB and found a significantly higher growth suppressive effect than single treatments of each. Even a complete regression of tumors was observed in three of five mice treated with this combination while with single treatment no tumor regression was observed. Tumors treated with the combination showed higher numbers of TUNEL positive cells than those treated with a single modality. Moreover, necrotic changes were more evident in tumors treated with the combination than separately, a compatible finding to the observation that vascularity revealed by CD34 staining was poorer in tumors treated with the combination than those treated with p53 gene or SB alone. This was further supported by the finding that BAI-1 (brain specific angiogenesis inhibitor-1), an inhibitor of vascularization, was induced by SB treatment in KATO-III and HuH7 cells transfected with Ad-p53. Thus SB was shown to be an efficient potentiator of p53 gene therapy for cancer.

Adenoviridae↗

Human mesenchymal stem cells xenografted directly to rat liver are differentiated into human hepatocytes without fusion.

Hepatic transdifferentiation of bone marrow cells has been previously demonstrated by intravenous administration of donor cells, which may recirculate to the liver after undergoing proliferation and differentiation in the recipient's bone marrow. In the present study, to elucidate which cellular components of human bone marrow more potently differentiate into hepatocytes, we fractionated human bone marrow cells into mesenchymal stem cells (MSCs), CD34+ cells, and non-MSCs/CD34- cells and examined them by directly xenografting to allylalcohol (AA)-treated rat liver. Hepatocyte-like cells, as revealed by positive immunostaining for human-specific alpha-fetoprotein (AFP), albumin (Alb), cytokeratin 19 (CK19), cytokeratin 18 (CK18), and asialoglycoprotein receptor (AGPR), and by reverse transcription-polymerase chain reaction (RT-PCR) for expression of AFP and Alb mRNA, were observed only in recipient livers with MSC fractions. Cell fusion was not likely involved since both human and rat chromosomes were independently identified by fluorescence in situ hybridization (FISH). The differentiation appeared to follow the process of hepatic ontogeny, reprogramming of gene expression in the genome of MSCs, as evidenced by expression of the AFP gene at an early stage and the albumin gene at a later stage. In conclusion, we have demonstrated that MSCs are the most potent component in hepatic differentiation, as revealed by directly xenografting into rat livers.

Albumins↗

Telomerized human bone marrow-derived cell clones maintain the phenotype of hematopoietic-supporting osteoblastic and myofibroblastic stromal cells after long-term culture.

OBJECTIVE: Gene transfer of the telomerase catalytic subunit (TERT) into primary human stromal cells prolonged their lifespan. However, primary human stromal cells are actually composed of adipocytes, myofibroblasts, osteoblasts, etc. Our objective was to investigate the phenotype and hematopoietic-support of the human telomerized stromal cell (HTS) in clonal level. MATERIALS AND METHODS: We established HTS clones (HTS-1 to HTS-9) from a parental population of HTSs by limiting dilution. Hematopoietic-supporting activity of the HTS clones was examined by coculturing with CD34(+) cells. RESULTS: HTS-1 to HTS-3 contained alkaline phosphatase (ALP)(+) cells, and HTS-4 to HTS-9 were composed of both ALP(+) and alpha-smooth muscle actin-positive cells. Although all HTS clones exhibited normal growth kinetics, one of the HTS clones exhibited a chromosomal abnormality. Moreover, the parental population of the HTS cells acquired an increased growth rate and anchorage independence after 4 years of culturing. Expression of hematopoietic growth factors, such as stem cell factor, angiopoietin-1, and hedgehog mRNA was detected in all HTS clones. The degree of hematopoietic progenitor support differed between the HTS clones, and the expansion level of CD34(+) cells was the highest in HTS-8. CONCLUSION: Human telomerized stromal cell clones exhibited the phenotype of hematopoietic supporting osteoblastic and myofibroblastic cells after long-term culture. Clinical application of HTS cells should be limited because of their potential for neoplastic transformation after hTERT gene transfer. HTS cells may be useful for analyzing the molecular mechanism of hematopoietic support of human stromal cells.

Bone Marrow Cells↗

Mesenchymal stem cells that produce neurotrophic factors reduce ischemic damage in the rat middle cerebral artery occlusion model.

Mesenchymal stem cells (MSC) were reported to ameliorate functional deficits after stroke in rats, with some of this improvement possibly resulting from the action of cytokines secreted by these cells. To enhance such cytokine effects, we previously transfected the telomerized human MSC with the BDNF gene using a fiber-mutant adenovirus vector and reported that such treatment contributed to improved ischemic recovery in a rat transient middle cerebral artery occlusion (MCAO) model. In the present study, we investigated whether other cytokines in addition to BDNF, i.e., GDNF, CNTF, or NT3, might have a similar or greater effect in this model. Rats that received MSC-BDNF (P < 0.05) or MSC-GDNF (P < 0.05) showed significantly more functional recovery as demonstrated by improved behavioral test results and reduced ischemic damage on MRI than did control rats 7 and 14 days following MCAO. On the other hand, rats that received MSC-CNTF or MSC-NT3 showed neither functional recovery nor ischemic damage reduction compared to control rats. Thus, MSC transfected with the BDNF or GDNF gene resulted in improved function and reduced ischemic damage in a rat model of MCAO. These data suggest that gene-modified cell therapy may be a useful approach for the treatment of stroke.

Animals↗

Mesenchymal stem cells (MSC) as therapeutic cytoreagents for gene therapy.

We developed human mesenchymal stem cell (MSC) lines that could differentiate into various tissue cells including bone, neural cells, bone marrow (BM) stromal cells supporting the growth of hematopoietic stem cell (HSC), and so-called 'tumor stromal cells' mixing with tumor cells. We investigated the applicability of MSC as therapeutic cell transplanting reagents (cytoreagents). Telomerized human BM derived stromal cells exhibited a prolonged lifespan and supported the growth of hematopoietic clonogenic cells. The gene transfer of Indian hedgehog (Ihh) remarkably enhanced the HSC expansion supported by the human BM stromal cells. Gene-modified MSC are useful as therapeutic tools for brain tissue damage (e.g. brain infarction) and malignant brain neoplasms. MSC transplantation protected the brain tissue from acute ischemic damage in the midcerebral artery occlusion (MCAO) animal model. Brain-derived neurotrophic factor (BDNF)-gene transduction further enhanced the protective efficacy against the ischemic damage. MSC possessed excellent migratory ability and exerted inhibitory effects on the proliferation of glioma cells. Gene-modification of MSC with therapeutic cytokines clearly augmented the antitumor effect and prolonged the survival of tumor-bearing animals. Gene therapy employing MSC as a tissue-protecting and targeting cytoreagent would be a promising approach.

Animals↗

Expansion of CD34+ cells on telomerized human stromal cells without losing erythroid-differentiation potential in a serum-free condition.

Erythropoiesis progresses from stem cell expansion on stromal cells through the formation of an erythroblastic island. Our aim was to assess the feasibility of using human stromal cells for erythroid production and differentiation. When cord blood CD34+ cells were cocultured with telomerized human stromal cells (hTERT-stromal cells) for 2 weeks, the CD34+ cells and burst-forming units-erythroid (BFU-E) significantly expanded, and a few hematopoietic cells transmigrated below the stromal layer. When nonadherent hematopoietic progenitor cells that had expanded above the hTERT-stromal cells (group B) were collected and subjected to our erythroid-differentiation protocol, they differentiated into erythroblasts with a slight hemoglobin synthesis. When the few hematopoietic cells that had transmigrated below the stromal layer were expanded for an additional 2 to 6 weeks, they exhibited a cobblestone-like appearance, and a large amount of BFU-E clambered weekly from the underside of the stromal layer to above the stromal layer (group C). When the hematopoietic progenitor cells in group C were subjected to the erythroid-differentiation protocol, large numbers of mature erythroblasts (more than 300,000 times the initial CD34+ cell number) were produced. Our hTERT-stromal expansion protocol may contribute to the construction of a system for large-scale, long-term production of erythroid cells.

Antigens, CD34↗

[Essential thrombocythemia associated with incomplete type intestinal Behçet disease during hydroxyurea treatment].

A 77-year-old man was diagnosed as having essential thrombocythemia in 1992. Treatment with hydroxyurea was started in 1997, which stabilized the platelet count. The patient then suffered from pharyngalgia and rhinitis with a high fever, immediately after which he developed tarry stools and anemia and was admitted to our hospital. The physical examination revealed splenomegaly, oral aphthous ulcers, genital ulcers and skin lesions on the lower limbs. His hematological and biochemical tests revealed anemia and increased level of C-reactive protein. He also had an HLA-B51 phenotype. The findings of gastro-intestinal and colon fiberoscopy showed a duodenal ulcer and multiple ulcers on ascending colon. He was thus diagnosed as having intestinal tract-type Behçet disease. After withdrawal of the hydroxyurea administration, the intestinal ulcers, oral aphthous ulcers and genital ulcers improved.

Aged↗

[Two cases of primary skeletal muscle lymphoma, and a review of the literature].

Here we report two cases of primary skeletal muscle lymphoma. The first patient was an 82-year-old man. On April 2004, he was referred to our hospital because of swelling of the right upper arm. Magnetic resonance imaging (MRI) showed an area which was isointense on T1 and hyperintense on T2-weighted imaging compared with normal skeletal muscle. The size of the tumor was 5 x 7 x 13 cm. Following pathological, flow cytometric and genetic analyses of the specimen, we diagnosed the tumor as a non-Hodgkin lymphoma of the T-cell rich diffuse large B-cell type. The second patient was an 87-year-old man. He was admitted to our hospital on July 2004, under the chief complaint of swelling of the right thigh. MRI revealed a giant tumor mass of the right thigh which was isointense on T1 and hyperintense on T2 imaging. The patient was diagnosed by open biopsy as having diffuse large B-cell lymphoma. We could find only 62 cases of primary skeletal muscle lymphoma through a MEDLINE search. We report on our two cases with a review of the literature.

Aged, 80 and over↗

Indian hedgehog gene transfer augments hematopoietic support of human stromal cells including NOD/SCID-beta2m-/- repopulating cells.

Hematopoietic stem cells (HSCs) are a subset of bone marrow cells that are capable of self-renewal and of giving rise to all types of blood cells. However, the mechanisms involved in controlling the number and abilities of HSCs remain largely unknown. The Indian hedgehog (Ihh) signal has an essential role in inducing hematopoietic tissue during embryogenesis. We investigated the roles of the Ihh in coculture with CD34+ cells and human stromal cells. Ihh mRNA was expressed in primary and telomerized human (hTERT) stromal cells, and its receptor molecules were detected in CD34+ cells. Ihh gene transfer into hTERT stromal cells enhanced their hematopoietic supporting potential, which was elevated compared with control stromal cells, as indicated by the colony-forming units in culture (CFU-Cs) (26-fold +/- 2-fold versus 59-fold +/- 3-fold of the initial cell number; mixed colony-forming units [CFU-Mix's], 63-fold +/- 37-fold versus 349-fold +/- 116-fold). Engraftments of nonobese diabetic/severe combined immunodeficiency-beta2m-/- (NOD/SCID-beta2-/-) repopulating cells (RCs) expanded on Ihh stromal cells were significantly higher compared with control coculture results, and engraftment was neutralized by addition of an antihedgehog antibody. Limiting dilution analysis indicated that NOD/SCID-beta2m-/- RCs proliferated efficiently on Ihh stromal cells, compared with control stromal cells. These results indicate that Ihh gene transfer could enhance the primitive hematopoietic support ability of human stromal cells.

Animals↗

Wnt3 modulates the characteristics and cobblestone area-supporting activity of human stromal cells.

OBJECTIVE: Our objective was to investigate the expression and significance of Wnt proteins in adult human hematopoietic-supporting stromal cells. METHODS: Degenerate reverse transcription-polymerase chain reaction was performed to screen telomerized human stromal cells (hTERT-stromal cells) and multipotent mesenchymal cells (hTERT-MSCs) for expression of Wnt genes. We studied the actions of Wnt proteins by overexpressing them in stromal cells and MSCs by retrovirus-mediated gene transfer. RESULTS: The hTERT-stromal and primary stromal cells expressed Wnt5A, while hTERT-MSCs and primary MSCs expressed Wnt3 and Wnt5A. Gene transfer of Wnt5A slightly reduced the growth rate of hTERT-stromal cells, but did not affect their morphology. In contrast, gene transfer of Wnt3 into both hTERT-stromal cells and hTERT-MSCs enhanced Wnt-betacatenin signaling, and caused remarkable morphological changes and growth retardation. Upon 2-week co-culture, expansion of clonogenic cells on Wnt5A-stromal cells was superior to that on control stromal cells. However, expansion of CD34+ cells on Wnt3-stromal cells did not differ from that on control stromal cells. Moreover, there was a drastic reduction in the formation of cobblestone area (CA) underneath Wnt3-stromal cells compared with that underneath control stromal cells. CONCLUSION: These results suggest that Wnt3 plays an important role in regulating characteristics and CA support activity of stromal cells.

Antigens, CD34↗

BDNF gene-modified mesenchymal stem cells promote functional recovery and reduce infarct size in the rat middle cerebral artery occlusion model.

Examination of the clinical therapeutic efficacy of using bone marrow stromal cells, including mesenchymal stem cells (MSC), has recently been the focus of much investigation. MSC were reported to ameliorate functional deficits after stroke in rats, with some of this improvement possibly resulting from the action of cytokines secreted by these cells. To enhance such cytokine effects, we transfected telomerized human MSC with the BDNF gene using a fiber-mutant F/RGD adenovirus vector and investigated whether these cells contributed to improved functional recovery in a rat transient middle cerebral artery occlusion (MCAO) model. BDNF production by MSC-BDNF cells was 23-fold greater than that seen in uninfected MSC. Rats that received MSC-BDNF showed significantly more functional recovery than did control rats following MCAO. Specifically, MRI analysis revealed that the rats in the MSC-BDNF group exhibited more significant recovery from ischemia after 7 and 14 days. The number of TUNEL-positive cells in the ischemic boundary zone was significantly smaller in animals treated with MSC-BDNF compared to animals in the control group. These data suggest that MSC transfected with the BDNF gene may be useful in the treatment of cerebral ischemia and may represent a new strategy for the treatment of stroke.

Adenoviridae↗

Adenovirus-mediated transfer of siRNA against survivin induced apoptosis and attenuated tumor cell growth in vitro and in vivo.

Gene targeting using short interfering RNA (siRNA) has become a common strategy to explore gene function because of its prominent efficacy and specificity. For the application of siRNA technology to gene therapy, however, still more efficient transduction of siRNA into target cells is needed. In this study, we developed an adenoviral vector harboring a tandem-type siRNA expression unit, in which sense and antisense strands composing the siRNA duplex were separately transcribed by two human U6 promoters. Targeting survivin, an antiapoptotic molecule widely overexpressed in malignancies but not detected in terminally differentiated adult tissues, this type of adenoviral vector (Adv-siSurv) successfully exerted a gene knockdown effect and induced apoptosis in HeLa, U251, and MCF-7 cells. These cancer cells, once infected with Adv-siSurv, displayed remarkably attenuated growth potential, both in vitro and in vivo. Moreover, intratumoral injection of Adv-siSurv significantly suppressed tumor growth in a xenograft model using U251 glioma cells. This novel modality may be a promising tool for cancer therapy.

Adenoviridae↗

[Successful treatment with antiviral agents for human herpesvirus type 6 encephalitis following reduced intensity stem cell transplantation in a patient with myelodysplastic syndrome].

We report here a patient who suffered from PCR-confirmed human herpesvirus type 6 (HHV-6) encephalitis following reduced intensity stem cell transplantation (RIST) from her HLA-matched sibling donor. A 66-year-old woman with MDS-RA underwent RIST from her HLA-matched brother. Engraftment was favorable and grade 2 GVHD (skin and intestine) was observed with good response to 60 mg of prednisolone. On day 162, she developed fever, headache, diplopia, disorientation and abnormal neurological findings including cervical stiffness and nystagmus. An analysis of cerebrospinal fluid (CSF) revealed 80 cells/microl, a glucose level of 50 mg/dl and a protein level of 97 mg/dl on day 162. Although computed tomography (CT) of the brain and electroencephalography (EEG) were nonspecific, HHV-6 was detected in the CSF using polymerase chain reaction (PCR) techniques and the patient was diagnosed as having encephalitis due to local reactivation of HHV-6. Administration of ganciclovir (GCV) and acyclovir (ACV) were started from day 162. Treatment with antiviral agents was effective, with total resolution of her symptoms and the DNA of this virus disappeared from the CSF after 23 days of treatment. This case shows that HHV-6 infection has to be considered in patients with neurological symptoms following stem cell transplantation, and suggests the necessity of PCR for HHV-6 virus from the CSF.

Acyclovir↗