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Biomedical subjects

S Asano

Publications and source records attributed to S Asano.

At least 73 records · Page 4Linked to original sources
PubMed2000

Hyperfunction of neutrophils in a patient with BCR/ABL negative chronic myeloid leukemia: a case report with in vitro studies.

BACKGROUND: Among patients diagnosed with chronic myeloid leukemia (CML), a small percentage lack a BCR/ABL fusion gene, a landmark of CML. Their clinical features are distinct from patients with BCR/ABL positive CML, although to the authors' knowledge the pathogenesis to date has been unknown. METHODS: A 50-year-old female patient with BCR/ABL negative CML and multiple complications of Graves disease, Sweet syndrome, and a fatal pulmonary alveolar proteinosis (PAP) is described in the current study. To show a clonal origin of her myeloid cells, hypoxanthine phosphoribosyltransferase (HPRT) assay was applied. Because the patient developed a progressive and fatal neutrophilia, a screening of cell functions in neutrophilic lineage, including in vitro colony assay of her bone marrow cells and production of superoxide and interleukin-8 (IL-8) by blood neutrophils was performed. RESULTS: Southern blot analysis based on the polymorphism of the HPRT gene was compatible with monoclonality of her neutrophils. The patient had an increased amount of bone marrow granulocyte-macrophage progenitor cells, which formed colonies in response to a very low dose (0.1 ng/mL) of granulocyte-colony stimulating factor. In vitro production of superoxide and IL-8, which is an inducer of positive chemotaxis of neutrophils, by her peripheral neutrophils was markedly augmented. Her bronchoalveolar lavage fluid also contained a significant amount of IL-8 as well as an unusual infiltration of neutrophils. CONCLUSIONS: In the patient in the current study, hyperfunction of the neutrophils might have contributed to the onset of PAP as well as Sweet syndrome and to the pathogenesis of BCR/ABL negative CML.

Bone Marrow↗
PubMed2000

IL-12 responsiveness and expression of IL-12 receptor in human peripheral blood monocyte-derived dendritic cells.

We analyzed the expression of IL-12Rbeta1 and IL-12Rbeta2 and the role of IL-12 in the activation of monocyte-derived dendritic cells (DCs) via IL-12Rbeta1-mediated signaling events. Flow cytometric analysis revealed that IL-12Rbeta1 was expressed in T cells, Con A blasts, and monocyte-derived DCs, but not in monocytes, while its transcript was detected in all of these cell types. Transcriptional expression of IL-12Rbeta2 was observed in T cells, Con A blasts, and monocyte-derived DCs, but not monocytes. The ligation of DCs as well as Con A blasts by IL-12 induced the production of GM-CSF, IL-1beta, IL-6, TNF-alpha, and IFN-gamma at the transcription levels. Furthermore, stimulation of DCs with IL-12 induced IL-12p40 transcript, but not IL-12p35 transcript, whereas this stimulation caused the expressions of both transcripts in Con A blasts. Stimulation of DCs with IL-12 caused a tyrosine phosphorylation of several intracellular proteins, and the pattern of these events were distinct from those of IL-12-stimulated Con A blasts. IL-12 also induced tyrosine phosphorylation of IL-12Rbeta1 as well as recruitment of several tyrosine-phosphorylated proteins to IL-12Rbeta1 in DCs and Con A blasts. Receptor engagement of DCs as well as Con A blasts by IL-12 resulted in activation of Janus kinase 2 and Tyk2 kinases and Stat3 and Stat4 transcription factors and the association of these proteins to IL-12Rbeta1. Stimulation with IL-12 caused a tyrosine phosphorylation and enzymatic activity of a family of mitogen-activated protein kinases, p38mapk. These results suggest that IL-12 acts directly on DCs to induce their functional activation via IL-12Rbeta1-mediated signaling events.

Cells, Cultured↗
PubMed2000

A method to identify cDNAs based on localization of green fluorescent protein fusion products.

We previously established a high-efficiency, retrovirus-mediated expression cloning method. Using this system, we now have developed an expression cloning method (FL-REX; fluorescence localization-based retrovirus-mediated expression cloning) in which cDNAs can be isolated based on the subcellular localization of their protein products. Complementary DNAs generated from mRNA using random hexamers were fused to the cDNA of green fluorescent protein (GFP) in the pMX retrovirus vector. The resulting cDNA-GFP fusion library was transfected into retrovirus-packaging cells, and the derived retroviruses were used to infect NIH 3T3 cells. Infected cells then were screened to identify cDNAs of interest through the subcellular localization of the GFP-fusion products. Using FL-REX, we have identified 25 cDNAs, most of which showed reasonable subcellular localization as GFP-fusion proteins, indicating that FL-REX is useful for identification of proteins that show specific intracellular localization.

3T3 Cells↗
PubMed2000

The roles of carbohydrate chains of the beta-subunit on the functional expression of gastric H(+),K(+)-ATPase.

Gastric H(+),K(+)-ATPase consists of alpha and beta-subunits. The alpha-subunit is the catalytic subunit, and the beta-subunit is a glycoprotein stabilizing the alpha/beta complex in the membrane as a functional enzyme. There are seven putative N-glycosylation sites on the beta-subunit. In this study, we examined the roles of the carbohydrate chains of the beta-subunit by expressing the alpha-subunit together with the beta-subunit in which one, several, or all of the asparagine residues in the N-glycosylation sites were replaced by glutamine. Removing any one of seven carbohydrate chains from the beta-subunit retained the H(+),K(+)-ATPase activity. The effects of a series of progressive removals of carbohydrate chains on the H(+),K(+)-ATPase activity were cumulative, and removal of all carbohydrate chains resulted in the complete loss of H(+), K(+)-ATPase activity. Removal of any single carbohydrate chain did not affect the alpha/beta assembly; however, little alpha/beta assembly was observed after removal of all the carbohydrate chains from the beta-subunit. In contrast, removal of three carbohydrate chains inhibited the surface delivery of the beta-subunit and the alpha-subunit assembled with the beta-subunit, indicating that the surface delivery mechanism is more dependent on the carbohydrate chains than the expression of the H(+),K(+)-ATPase activity and alpha/beta assembly.

Animals↗
PubMed2000

A new ETV6/TEL partner gene, ARG (ABL-related gene or ABL2), identified in an AML-M3 cell line with a t(1;12)(q25;p13) translocation.

The ETV6/TEL gene has been reported to fuse to PDGFRbetab MDS1/EVI1, BTL, ACS2, STL, JAK2, ABL, CDX2, TRKC, AML1, and MN1. Among them, PDGFRbeta, ABL, JAK2, and TRKC are tyrosine kinases (TK). We identified a novel ETV6 partner gene, ARG (ABL-related gene or ABL2), another TK gene in a cell line established from a patient with acute myelogenous leukemia (AML-M3) with a t(15;17)(q22;q11.2) and a t(1;12)(q25;p13), which has the remarkable feature to differentiate to mature eosinophils in culture with all-trans retinoic acid and cytokines. The ETV6/ARG transcripts consisted of exon 1 to 5 of ETV6 and the 3' portion of ARG starting from exon 1B or exon 2, resulting in an open reading frame for a fusion protein consisting of the entire PNT oligomerization domain of ETV6 and all of the functional domains of ARG including the TK domain. This is the same protein structure as identified in the other ETV6 TK fusion proteins. The reciprocal ARG/ETV6 transcript was not expressed, and the normal ETV6 allele was not deleted or rearranged. Although the ABL is known to be involved in various human malignancies, ARG has not been involved in human malignancies despite its high homology to ABL. Thus, this is the first report showing involvement of ARG in human leukemia. The ETV6/ARG protein may be involved in the unique differentiation capacity of this cell line. (Blood. 2000;95:2126-2131)

Adaptor Proteins, Signal Transducing↗
PubMed2000

The IVS4 + 4 A to T mutation of the fanconi anemia gene FANCC is not associated with a severe phenotype in Japanese patients.

Fanconi anemia (FA) is an autosomal recessive disease characterized by congenital anomalies, aplastic anemia, and a susceptibility to leukemia. There are at least 8 complementation groups (A through H). Extensive analyses of the FA group C gene FANCC in Western countries revealed that 10% to 15% of FA patients have mutations of this gene. The most common mutation is IVS4 + 4 A to T (IVS4), a splice mutation in intron 4, which has been found only in patients of Ashkenazi Jewish ancestry. When we screened 29 Japanese patients (20 unrelated patients and 4 families) using polymerase chain reaction-single strand conformation polymorphism, we found 8 unrelated patients homozygous for IVS4. This is apparently the first non-Ashkenazi-Jewish population for whom this mutation has been detected. The Ashkenazi Jewish patients homozygous for IVS4 have a severe phenotype, in comparison with other FA patients. Our analyses of Japanese patients indicate no significant difference between IVS4 homozygotes and other patients with regard to severity of a clinical phenotype. Thus, ethnic background may have a significant effect on a clinical phenotype in FA patients carrying the same mutation. (Blood. 2000;95:1493-1498)

Adolescent↗
PubMed2000

Identification of a melanoma antigen, PRAME, as a BCR/ABL-inducible gene.

In order to elucidate molecular events in BCR/ABL-induced transformation, we adopted a polymerase chain reaction (PCR)-based technique of differential display and compared mRNA expression in human factor-dependent cells, TF-1, with that in factor-independent cells, ID-1, which were established from TF-1 cells by transfection of BCR/ABL. Cloning and sequencing of a gene which was upregulated in ID-1 cells revealed that the gene was identical to a melanoma antigen, PRAME. Our present study demonstrated that PRAME was markedly expressed in primary leukemic cells with chronic myeloid leukemia (CML) in blastic crisis and Philadelphia (Ph)+-acute lymphoblastic leukemia (ALL), in which BCR/ABL played an important role as a pathogenic gene. Moreover, comparison of PRAME expression among CD34+ cells with CML in blastic, accelerated, and chronic phases revealed a higher expression in CML in advanced phases. Thus PRAME was considered to be a good candidate for a marker of Ph+-leukemic blast cells as well as a new target antigen of leukemic blast cells that cytotoxic T cells can recognize.

Antigens, Neoplasm↗
PubMed2000

Biological activity of human granulocyte colony stimulating factor with a modified C-terminus.

Granulocyte colony-stimulating factor (G-CSF) undergoes receptor-mediated internalization into target cells which are normally restricted to neutrophilic granulocytes and their committed progenitor cells, suggesting that it may be applicable as a myeloid cell-targeting vehicle. To test this notion, we constructed a cDNA encoding a human G-CSF/murine stem cell factor (mSCF) chimeric molecule in a mammalian expression vector and transfected NIH3T3 cells with this plasmid. The resulting chimeric cytokine consisted of the entire G-CSF sequences fused to Lys148 of mSCF. It can be released from the surface membrane of NIH3T3 transformants through proteolytic cleavage at Ala164 of mSCF. The culture media conditioned by a number of stable transformants, which were confirmed by an enzyme-linked immunosorbent assay (ELISA) to secrete an hG-CSF derivative, were examined for their ability to stimulate CFU-G-derived colony formation as well as the proliferation of G-CSF-dependent NFS-60 cells. The results indicated that this C-terminus modified version of hG-CSF is as potent as recombinant hG-CSF in both assays.

3T3 Cells↗
PubMed2000

TCR-Vbeta repertoire analysis with RT-PCR was useful for the early detection of pulmonary relapsed T-cell lymphoma after autologous peripheral blood stem cell transplantation.

Pulmonary recurrence of malignant lymphoma is a rare event after stem cell transplantation. We report here a 45-year-old male who was successfully diagnosed with relapsed pulmonary T-cell lymphoma using an RT-PCR method. Clonal expansion of T cells expressing identical TCR V-D-J junction size (Vbeta5-Jbeta1.5) was demonstrated in lymphocyte groups obtained from both bronchoalveolar lavage fluid at relapse, and paraffin embedded lymph node samples resected when he was first diagnosed with angioimmunoblastic T-cell lymphoma. This method provided evidence to diagnose relapsed pulmonary angioimmunoblastic T-cell lymphoma in its early phase.

Bronchoalveolar Lavage Fluid↗
PubMed2000

MHC (major histocompatibility complex)-DRB genes and polymorphisms in common marmoset.

A New World monkey, the common marmoset (Callithrix jacchus), will be used as a preclinical animal model to study the feasibility of cell and gene therapy targeting immunological and hematological disorders. For elucidating the immunogenetic background of common marmoset to further studies, in the present study, polymorphisms of MHC-DRB genes in this species were examined. Twenty-one Caja-DRB exon 2 alleles, including seven new ones, were detected by means of subcloning and the polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) methods followed by nucleotide sequencing. Based on the alignment of these allele sequences, we designed two pairs of specific primers and established a PCR-SSCP method for DNA-based histocompatibility typing of the common marmoset. According to the family segregation data and phylogenetic analyses, we presumed that Caja-DRB alleles could be classified into five different loci. Southern blotting analysis also supported the existence of multiple DRB loci. The patterns of nucleotide substitutions suggests that positive selection operates in the antigen-recognition sites of Caja-DRB genes.

Alleles↗
PubMed2000

An intrapulmonary teratoma associated with bronchiectasia containing various kinds of primordium: a case report and review of the literature.

An intrapulmonary teratoma (IPT), multiloculated and bronchiectatic, with two polyps inside a 23-year-old man is reported. The IPT, a very rare benign cystic lesion, was communicating with segmental bronchus and was removed by a segmental resection from the upper lobe of the left lung. The teratoma contained various kinds of primordial derivatives, such as mesoderm, ectoderm, and endoderm. Though 65 cases of IPT have been reported in the literature (1839-1996), in the present case there were over 15 germ derivatives, the largest number reported to date. The tumor contained thymic tissue, apart from mediastinum, which may be significant in relation to the pathogenesis of IPT. Clinical manifestations, age, and gender distributions and the kind of germ cell derivatives are discussed.

Adult↗
PubMed2000

Management of nodular goiters and their operative indications.

It remains controversial whether or not nodular goiters should be treated surgically or conservatively. This report reviews our 9-year experience of treating nodular goiters in 334 patients, 44 of whom underwent surgery, and compares the methods of treatment employed from 1990 to 1999 with those employed from 1971 to 1989 when 171 operations were carried out. In accordance with diagnoses made using fine-needle aspiration biopsy (FNAB) and ultrasonography, patients were treated as follows. Those with cysts were given percutaneous ethanol injection therapy (PEIT), and those with solid tumors underwent surgery if cancer of >class 3 was suspected or if the tumors were >3 cm. Consequently, 44 patients with solid tumors underwent surgery and 72 with cysts were treated by PEIT. The number of operations performed annually decreased to half of the pre-1990 figure. During the follow-up of those patients who did not undergo surgery, four with solid tumors and two with cysts later required surgery due to suspected carcinoma of >class 3 in 3 patients or as a result of personal choice in 3 patients. The growth of solid tumors was not able to be measured in most cases. These results indicate that the number of operations performed for nodular goiters can be reduced by PEIT. An accurate cytological diagnosis supports this therapeutic strategy.

Biopsy, Needle↗
PubMed2000

Maxizymes, novel allosterically controllable ribozymes, can be designed to cleave various substrates.

We demonstrated previously that an allosterically controllable novel ribozyme, designated the maxizyme, is a powerful tool for disruption of an abnormal chimeric RNA target [BCR-ABL (b2a2) mRNA], and we proposed that it might provide the basis for future gene therapy for the treatment of chronic myelogenous leukemia (Kuwabara et al. Mol. Cell 1998, 2, 617-627). The maxizyme has sensor arms that can recognize a specific sequence and, in the presence exclusively of such a specific sequence, it can form a cavity for capture of catalytically indispensable Mg2+ ions. Cleavage of the target RNA then occurs at a site distant from the specific sequence. Clearly, the specific sequences recognized by sensor arms should not be limited to those of the above mentioned abnormal chimeric target. Thus, to demonstrate the general applicability of maxizyme technology, we constructed maxizymes targeted to other mRNAs, such as PML-RAR alpha mRNA, sDLST mRNA, and BCR-ABL (b1a2) mRNA, that are not cleaved with high specificity by the wild-type hammerhead ribozyme. Specific and efficient cleavage in vitro of these mRNAs by the custom-designed maxizymes demonstrated clearly that maxizyme technology is not limited to a specific case but may have broad general applicability in molecular biology and, also, in a clinical setting.

Autoradiography↗
PubMed2000

Congenital laryngeal atresia: two autopsy cases, one describing the use of computed tomography.

Two autopsy cases of congenital laryngeal atresia (CLA) were studied. In the first case (a boy delivered at 37 weeks of gestation) the subglottic lumen was almost totally occupied by a dome shaped cricoid cartilage with a pharyngotracheal duct (PTD). No tracheoesophageal fistula (TEF) was found. In the second case (a girl born at 41 weeks of gestation) histology showed that the subglottic lumen was almost occluded by an epithelial lamina and a dome-shaped cricoid cartilage. Again no TEF was found. Both cases had PTD and showed normal development of the lungs. These deformities coincided with Smith & Bain's type II subglottic atresia. The anatomy of the lesion was confirmed by postmortem three-dimensional reconstruction CT, the use of which has not previously been reported.

Autopsy↗
PubMed2000

Donor leukocyte infusion for Japanese patients with relapsed leukemia after allogeneic bone marrow transplantation: lower incidence of acute graft-versus-host disease and improved outcome.

To clarify the role of donor leukocyte infusion (DLI) in the treatment of leukemia relapsing after allo-BMT, data from 100 patients were collected from 46 facilities in Japan and analyzed with respect to the efficacy and adverse effects of donor leukocyte infusion. Complete remission was achieved in 11 of 12 (91%) patients with relapsed chronic myelogenous leukemia (CML) in chronic phase, three of 11 (27%) with CML in the acute phase, eight of 21 (38%) with acute myelogenous leukemia (AML), six of 23 (25%) with acute lymphoblastic leukemia (ALL) and five of 11 (45%) with myelodysplastic syndrome (MDS). The probability of remaining in CR at 3 years was 82% in CML patients in the chronic phase, but 0% in those with CML in the acute phase, 7% in those with AML, 0% with ALL and 33% with MDS. Acute GVHD (>/=2) developed in 31 of 89 (34%) patients with HLA-identical related donors and was fatal for seven (7%). Cytopenia developed in 21 of 94 (22%) with no associated fatalities. When the outcome of patients with CML in CP and MDS was analyzed, development of GVHD, cytopenia, or both, was associated with a higher GVL effect (15 of 16, 93%) than in those without adverse affects (one of 6, 17%). A leukocyte dose of 5 x 107/kg of recipient body weight appeared to be optimal as an initial dose of DLI. Given the relatively low incidence of acute GVHD and the similar GVL effect, DLI may be more beneficial to patients in Japan with recurrent leukemia than to those in Western countries. Bone Marrow Transplantation (2000) 26, 769-774.

Acute Disease↗
PubMed2000

Improvement in bronchiolitis obliterans organizing pneumonia in a child after allogeneic bone marrow transplantation by a combination of oral prednisolone and low dose erythromycin.

We report a 13-year-old boy who developed dyspnea at rest 1 year after the occurrence of cGVHD following an allogeneic bone marrow transplant (BMT). Pulmonary function data, imaging studies, lung biopsy, and bronchoalveolar lavage were consistent with the diagnosis of bronchiolitis obliterans organizing pneumonia (BOOP). Although reports suggest that oral methylprednisolone or methylprednisolone pulse therapies improve BOOP after BMT, we treated our patient with a combination of oral prednisolone (1 mg/kg) and low dose erythromycin (10 mg/kg) to avoid the side-effects of high-dose steroids. With this therapy, our patient showed clinical and radiological improvements within 1 week. The steroids were tapered off 12 months later and erythromycin was given for 14 months. We conclude that therapy consisting of a combination of oral prednisolone and low-dose erythromycin for BOOP after BMT may minimize the dose and duration of steroid use.

Administration, Oral↗
PubMed2000

Natural killer cell depletion by anti-asialo GM1 antiserum treatment enhances human hematopoietic stem cell engraftment in NOD/Shi-scid mice.

The scid mutation was backcrossed on to the NOD/Shi mouse background, resulting in the development of NOD/Shi-scid mice, which showed lack of mature lymphocytes, macrophage dysfunction and absence of circulating complement, but were not as impaired in natural killer (NK) cell activity as NOD/LtSz-scid mice. We then examined the effect of recipient NK cell depletion by anti-asialo GM1 antiserum on the repopulation of human cord blood (CB) hematopoietic stem cells (HSC) in NOD/Shi-scid mice to clarify the role of recipient NK cells in human HSC engraftment. The anti-asialo GM1 antiserum treatment significantly enhanced the engraftment of CB CD34+ cells, but did not affect the differentiation of the engrafted HSC into each hematopoietic lineage. The NK cell depletion was effective at early stages of the engraftment, but not 3 weeks after the transplantation. The anti-asialo GM1 antiserum treatment did not improve the engraftment by human HSC in scid mice which lack mature lymphocytes, but show neither macrophage dysfunction nor a reduction in circulating complement, indicating that macrophages and/or complement also have roles in HSC graft rejection. The present study indicates that the preconditioning targeting of recipient NK cells in addition to T cell suppression and myeloablation might prevent HSC graft failure, and that NOD/Shi-scid mice treated with anti-asialo GM1 antiserum could provide a useful tool for evaluating the repopulating ability of transplantable human HSC.

Animals↗