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Biomedical subjects

K Oshimi

Publications and source records attributed to K Oshimi.

At least 91 records · Page 5Linked to original sources
PubMed1994

Interleukin-11.

Interleukin-11 (IL-11), a stromal cell-derived cytokine, has been known to act widely in hematopoietic and non-hematopoietic systems. IL-11 supports the growth of certain types of plasmacytoma and hybridoma cells, acts with interleukin-3 (IL-3) in shortening the Go period of early progenitors. IL-11 supports megakaryocyte colony formation and maturation, and acts as an autocrine growth factor in megakaryoblastic cell lines. In addition, IL-11 stimulates erythrocytopoiesis, enhances antigen-specific antibody responses, induces the synthesis of acute phase proteins, inhibits lipoprotein lipase activity and adipocyte differentiation, and promotes neuronal development. Administration of rhIL-11 to mice resulted in an increase of neutrophils and platelets. The human IL-11 gene is localized at 19q13.3-13.4, and codes 199 amino acids and 23 kDa with no N glycosylation. Its receptor and signal transduction share partially those of interleukin-6 (IL-6). Further analysis of its role in normal and pathological state is necessary to determine the exact function and its application for clinical uses.

Acute-Phase Proteins↗
PubMed1994

Combination of interleukin-2-stimulated lymphocytes and bispecific antibodies that efficiently lyse leukemic cells does not affect bone marrow CD34-positive stem cell function in vitro.

We have recently reported that a combination of lymphokine-activated killer (LAK) cells and bispecific antibodies (BsAb) efficiently lysed autologous and allogeneic leukemic blasts that had surface antigens reactive with the BsAb. The effector cells used in that experiment were peripheral blood mononuclear cells stimulated with interleukin-2 (IL-2) for 2 weeks, with the initial addition of anti-CD3 moAb; these were termed T3-LAK effector cells. In this study, we examined the effects of T3-LAK cells and BsAb on autologous normal CD34+ BM cells in both cytotoxicity and colony formation assays. When T3-LAK cells were incubated with CD34+ BM cells, low levels of cytotoxicity were induced against the CD34+ BM cells and the cytotoxicity was enhanced by the addition of anti-CD3 Fab' x anti-CD 13 Fab' BsAb but not by the addition of anti-CD3 Fab' x anti-CD10 Fab' BsAb. This enhancement appeared to be due to the lysis of CD34+CD13+ BM cells. When T3-LAK cells were preincubated with CD34+ BM cells in the presence or absence of the BsAb and plated for colony assay, neither the T3-LAK cells nor the BsAb affected granulocyte-macrophage or mixed-cell colony formation by CD34+ BM cells. Taken together with our previous finding that T3-LAK cells used in combination with the BsAb markedly inhibited colony formation by leukemic progenitor cells, these results indicate that this combination provides a potential new strategy for CD34+ BM cell purging in autologous BMT.

Antibodies, Bispecific↗
PubMed1994

[Nasal NK-cell lymphoma].

A 75-year-old man was admitted to our hospital on June 1st, 1993, because of nasal obstruction, epistaxis, fever, night sweats and weight loss. Examination disclosed a 2-cm white necrotic mass in the nasal septum, and a biopsy disclosed non-Hodgkin's lymphoma, diffuse, mixed-type. Imprint smears showed cytoplasmic azurophilic granules in the tumor cells. Dense granules were demonstrated by electron microscopy. The tumor cells were CD1-2+3-4-7+8-16+56+57-, and T cell receptor genes were in germline configuration. NK activity against K562 was strongly positive. Based on morphologic, phenotypic, immunogenotypic, and cytotoxic findings, the tumor cells seemed to be derived from activated NK cells. Because the tumor cells were positive for the EB virus and CD21 antigen, EB virus seemed to have infected CD21-positive NK cells and transformed them. MDR P-glycoprotein was also positive. This finding may explain why nasal lymphomas are resistant to chemotherapy and have a poor prognosis.

Cell Transformation, Viral↗
PubMed1993

Ca2+ response in single human T cells induced by stimulation of CD4 or CD8 and interference with CD3 stimulation.

A Ca2+ imaging method has been used to demonstrate simultaneously the magnitude and time course of the increase in the intracellular Ca2+ concentration ([Ca2+]i) in 10-30 individual human peripheral T cells following stimulation by anti-CD4 or anti-CD8 monoclonal antibody (MAb) as well as anti-CD3 MAb. The rise in [Ca2+]i began within 10 s of the introduction of the MAb and reached a peak of 240 nM (mean of 73 cells) in 20-40 s. The peak was followed by a slow decrease persisting for 6-8 min. Comparing Ca2+ responses in the presence and absence of external Ca2+, the rise in [Ca2+]i was found to be caused by both transient intracellular Ca2+ release and a long-lasting Ca2+ influx from outside the cell. Cross-linking of CD4 or CD8 using anti-IgG antibody augmented the response in individual cells, as seen in the higher peak (365-390 nM) and the longer duration (over 10 min). Simultaneous stimulation of CD3 and CD4 did not cause a summation of Ca2+ responses but caused a suppression in the CD3-mediated Ca2+ response. The results support the view that CD4 and CD8 play a role in signal transduction for T cell activation and that the CD4-derived signal interferes with the CD3-derived signal at some stage in the signalling pathway causing the Ca2+ response.

Antibodies, Monoclonal↗
PubMed1993

Expression of multidrug resistance P-glycoprotein on peripheral blood mononuclear cells of patients with granular lymphocyte-proliferative disorders.

Some patients with granular lymphocyte-proliferative disorders (GLPD) have been reported to have an aggressive clinical course with a poor prognosis and to be refractory to chemotherapy. In this study, expression of multidrug resistance P-glycoprotein on peripheral blood mononuclear cells (PBMC) of 11 patients with GLPD was examined by staining with MRK 16, a monoclonal antibody that binds to an external epitope of P-glycoprotein, and with the dye rhodamine, a known substance to be excreted from the cells through P-glycoprotein. Among those tested, the PBMC of six of eight patients with T-cell-type GLPD as well as those of three of three patients with natural killer cell-type GLPD expressed P-glycoprotein significantly. Furthermore, PBMC of two of two patients were also poorly stained with the dye rhodamine, and the treatment of PBMC with either verapamil or quinidine, multidrug resistance-reversing agents, led to their increased staining, suggesting that these PBMC actively release chemotherapeutic agents.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1993

A bispecific antibody enhances cytokine-induced killer-mediated cytolysis of autologous acute myeloid leukemia cells.

An anti-CD3 Fab' x anti-CD13 Fab' bispecific antibody (BsAb) was generated. This BsAb reacted with both CD3+ T cells and CD13+ acute myeloid leukemia (AML) cells. We investigated whether cytokine-stimulated peripheral blood mononuclear cells (PBMC) could lyse patient AML cells after addition of the BsAb. When interleukin-2 (IL-2)-stimulated PBMC were assayed for their cytotoxicity against 51Cr-labeled allogeneic and autologous CD13+ AML cells, their activity was markedly enhanced by the addition of the BsAb. PBMC stimulated with IL-2 plus anti-CD3 monoclonal antibody (MoAb) showed higher proliferative ability and higher cytotoxicity if this was expressed as lytic units per culture. IL-7-stimulated PBMC also exhibited enhanced cytotoxicity against CD13+ AML cells after addition of the BsAb. Ultrastructurally, CD13+ AML cells incubated with IL-2 plus anti-CD3 MoAb-stimulated PBMC and the BsAb showed apoptotic morphologic changes. A colony assay for AML blast progenitors showed that the colony formation of CD13+ AML cells was inhibited by the addition of autologous IL-2 plus anti-CD3 MoAb-stimulated PBMC, and that this inhibition was further enhanced by the addition of the BsAb. A colony assay for normal bone marrow progenitor cells showed that the addition of autologous IL-2 plus anti-CD3 MoAb-stimulated PBMC and the BsAb inhibited the formation of granulocyte-macrophage colonies and mixed-cell colonies. However, the degree of inhibition was smaller than that for the AML blast colonies. Taken together, these findings suggest that this BsAb may be useful for ex vivo purging of CD13+ AML cells in autologous bone marrow transplantation.

Antibodies, Monoclonal↗
PubMed1993

Interleukin-11 acts as an autocrine growth factor for human megakaryoblastic cell lines.

The cytokine interleukin-11 (IL-11) promotes normal human megakaryocytopoiesis in vitro. However, its role in abnormal megakaryocytopoiesis is not well known. Accordingly, we studied its effects on human megakaryoblastic cell lines CMK and Meg-J. IL-11 stimulated the proliferation of CMK and Meg-J in a dose-dependent manner with maximal growth being achieved at the concentration of 50 and 500 ng/mL, respectively. The growth of the cells was inhibited by anti-IL-11 antibody and IL-11 antisense oligonucleotides. IL-11 transcripts were detected in these two cell lines using a reverse transcriptase-polymerase chain reaction assay. These findings indicate that IL-11 might be an autocrine growth factor for megakaryoblastic cells. IL-11 transcripts also existed in other leukemia cell lines: HL-60, U937, and K562. However, the growth of these cells was not stimulated by IL-11, and was not inhibited by IL-11 antisense oligonucleotides. These results suggested that IL-11 might regulate malignant cells of the megakaryocytic lineage, in part by an autocrine loop.

Base Sequence↗
PubMed1993

Autophagolysosomes exhibiting lysosomophagy in the granular lymphocytes of patients with granular lymphocyte-proliferative disorders.

The ultrastructure of granular lymphocytes (GLs) in the peripheral blood of 12 patients with granular lymphocyte-proliferative disorders (GLPDs) was studied. Autophagolysosomes exhibiting so-called "lysosomophagy" were seen in the GLs of four of these patients but not in normal individuals. Because rod-shaped lysosomes beginning to enclose other lysosomes were seen, the autophagolysosomes exhibiting lysosomophagy in GLs were thought to be formed by the same wrapping mechanism. As far as we know, this is the first report of lysosomophagy in lymphocytes.

Adult↗
PubMed1993

The effects of leukemia inhibitory factor and interleukin 6 on the growth of acute myeloid leukemia cells.

The effects of leukemia inhibitory factor (LIF) and interleukin 6 (IL-6) on blast progenitors from acute myeloblastic leukemia (AML) were examined using a blast colony assay in a serum-free culture system. LIF and IL-6 stimulated colony growth in 2 and 5, respectively, of 11 cases studied. The simultaneous addition of LIF with granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin 3 (IL-3) or IL-6 produced a statistically significant increase of colony numbers in 3, 6 and 7 of 11 cases, respectively. Numbers of colonies increased significantly when IL-6 was added simultaneously with GM-CSF or IL-3 in 5 and 4 of 11 cases, respectively. LIF or IL-6 used in the primary culture did not significantly change the numbers of secondary colonies compared to GM-CSF. Previous exposure to LIF and IL-6 did not alter cellular phenotype or morphology, indicating that LIF and IL-6 did not induce the differentiation of fresh AML blasts.

Adult↗
PubMed1993

Circulating megakaryocyte progenitors in myeloproliferative disorders are hypersensitive to interleukin-3.

Previous studies have reported that megakaryocyte progenitors in myeloproliferative disorders (MPD) formed spontaneous megakaryocyte colonies without the addition of megakaryocyte colony-stimulating factor (Meg-CSF). To determine whether this spontaneous colony formation is due to autocrine proliferation of MPD megakaryocyte progenitors or to hypersensitivity to Meg-CSF that might exist in the culture system, we investigated colony-forming unit-megakaryocytes (CFU-Meg) in the peripheral blood of 11 MPD patients, using serum-free cultures. Spontaneous megakaryocyte colonies were observed in serum-free cultures of nonadherent mononuclear cells (NAdMNC) obtained from MPD patients with thrombocytosis, whereas the NAdMNC of MPD patients without thrombocytosis, that of patients with reactive thrombocytosis and normal subjects never formed spontaneous colonies. However, the spontaneous colonies from MPD patients with thrombocytosis disappeared in cultures using highly purified CD34-positive cells as target cells. To study the hypersensitivity of megakaryocyte progenitors to Meg-CSF, dose-response experiments were performed with interleukin-3 (IL-3). CFU-Meg from MPD patients with thrombocytosis showed maximal growth at the concentrations of IL-3 lower than those for normal subjects. CFU-Meg of MPD patients without thrombocytosis and that of patients with reactive thrombocytosis showed the same colony growth response to IL-3 as that of normal subjects. This result indicates that the CFU-Meg of MPD patients with thrombocytosis are hypersensitive to IL-3. It also suggests that spontaneous colony formation by NAdMNC is not due to the autocrine growth of megakaryocyte progenitors but is due to the hypersensitivity of megakaryocyte progenitors to Meg-CSF, such as IL-3, released by accessory cells. Furthermore, it is possible that such hypersensitivity of CFU-Meg to IL-3 might be a pathogenic factor in MPD with accompanying thrombocytosis.

Adult↗
PubMed1993

Peripheral expansion of gamma delta T cell receptor-positive cells in a patient with Crohn's disease.

A 13 year old boy with Crohn's disease had a prominent expansion (over 40%) of gamma delta T cell receptor-positive cells (gamma delta T cells) in the peripheral blood. The gamma delta T cells were gradually decreased from 48 to 22% in 18 months. Anti-gamma delta T cell receptor-triggered cytotoxicity was evident at onset and after 1 year. The significance of peripheral expansion of gamma delta T cells in a patient with Crohn's disease is discussed.

Adolescent↗
PubMed1993

[Mechanism of immunosuppressive therapy for aplastic anemia].

The mechanism of therapeutic effect of anti-lymphocyte globulin (ALG) and cyclosporin A (CyA) on patients with aplastic anemia was studied. When peripheral CD8 positive cells obtained before therapy were cocultured with bone marrow CD34 positive cells obtained after hematological recovery, the number of colony forming unit granulocyte-macrophage (CFU-GM) and burst forming unit erythroid (BFU-E) were decreased. This result indicates that ALG and CyA inhibits CD8 positive cells which suppress the growth of progenitor cells, resulting in the recovery of hematopoiesis. Next we investigated the plasma concentrations of cytokines including G-CSF, GM-CSF, IL-6, IL-1 alpha and IL-1 beta after ALG treatment. Although the elevation of plasma concentrations of G-CSF and GM-CSF after ALG treatment were found in 11 of 13 patients and in 2 of 13 patients respectively, cytokine production by ALG appeared to be unrelated to the therapeutic effect of ALG for aplastic anemia.

Adult↗
PubMed1993

Heterogeneity of CD7+ 4- 8- 1- leukemia: usefulness of cytoplasmic antigen detection for subclassification.

We identified CD3 and myeloperoxidase (MPO) antigens in the cytoplasm of leukemic cells from 15 patients with CD7+ 4- 8- 1- leukemia. Seven patients, five of whom had a mediastinal mass, had only cytoplasmic CD3 (cCD3) antigen; these seven were regarded as possibly being of T-lineage type. Six patients, one of whom had a mediastinal mass, showed both cCD3 and MPO; they were considered to have mixed lineage type. Two patients had neither cCD3 nor cytoplasmic myeloid antigens; they were therefore considered to have stem cell type. These two latter types were considered as the subgroups: mixed lineage or stem cell type. Patients with T-lineage type were good responders to L-17M therapy; four out of five who received L-17M therapy achieved complete remission. There were significant differences between the two subgroups in relapse-free survival, patients with T-lineage type exhibiting better prognosis than other types (p < 0.05).

Adult↗
PubMed1993

Laboratory findings and clinical courses of 33 patients with granular lymphocyte-proliferative disorders.

The hematological and immunological findings and clinical courses of 33 patients (13 male, 20 female; median age at presentation, 60 years) with granular lymphocyte-proliferative disorders (GLPD) are presented. Based on the surface phenotypes of peripheral blood granular lymphocytes (GL), the GLPD were divided into CD3+ T cell-lineage GLPD (T-GLPD) and CD3- CD16+ natural killer (NK) cell-lineage GLPD (NK-GLPD). Twenty-one patients had T-GLPD, and 12 had NK-GLPD. One patient with T-GLPD and two patients with NK-GLPD had progressive clinical courses and died of the disease despite receiving combination chemotherapy. Twelve patients with T-GLPD were found to have severe anemia at presentation or during the course of the disease; four of them fulfilled the diagnostic criteria of pure red cell aplasia, and the others had closely related conditions. Six of these 12 patients were treated with cyclophosphamide, and all responded to the treatment. In 16 patients, the clinical course was stable, and spontaneous regression was observed in two patients. Since some of the patients with NK-GLPD had stable clinical courses while some had progressive clinical courses, clinical findings in these two groups were compared. We found, taking into consideration our cases and those reviewed in the literature, that age less than 40 years, fever, lymph node swelling, hepatosplenomegaly, and GL with CD16(Leu-11)-CD56+CD57- phenotype and low or absent antibody-dependent cellular cytotoxicity seemed to be predictors of a progressive clinical course.

Adult↗
PubMed1993

Telomere reduction in hematologic cells.

The broken ends of chromosomes are unstable, and tandem fusion of telomeres has been observed in some tumors. Using Southern blot analysis, we report here telomeric DNA changes in hematologic cells. There was some variation in the length of the telomeric DNA in normal peripheral blood mononuclear cells obtained from four different individuals, ranging from 10 to 12 kilobases (kb), but there was little difference in signal strength. In two cell lines tested, HL-60 and K562, there was a telomeric sequence reduction of 2-4 kb and there was also a diminution of signal intensity. Reduction of the telomeric DNA array was also observed in two leukemic cases tested. The peak telomere length of the leukemic cells was 5 and 4 kb before and 10 and 7 kb after treatment, respectively, and in one case there was also a reduction in copy numbers of about 50%. Since no remarkable changes were detected in the Alu and alphoid sequences in either normal or leukemic cells, it appeared that the DNA change was specific to telomeric regions. Assessment of telomeric DNA changes may aid in determining the biological significance of leukemic cells.

Adult↗
PubMed1992

Interleukin-11 enhances human megakaryocytopoiesis in vitro.

We investigated the effect of recombinant human interleukin-11 (rhIL-11) on human megakaryocytopoiesis. Nonadherent and T-cell-depleted human bone marrow (BM) mononuclear cells were cultured in a serum-free agar culture system. rhIL-11 alone did not stimulate the growth of human megakaryocyte colonies. However, when rhIL-11 was combined with optimal or suboptimal doses of rhIL-3, the number and size of the megakaryocyte colonies increased. The same results were obtained when highly purified BM CD34-positive cells were used as target cells. Next, we investigated the effect of rhIL-11 on the ploidy of megakaryocytes. The ploidy distribution of individual cells in megakaryocyte colonies obtained by rhIL-11 in combination with rhIL-3 was significantly shifted towards higher values. Furthermore, when highly purified CD41-positive BM cells were cultured in the presence of rhIL-11, the ploidy distribution was shifted towards higher values. This effect was not suppressed by anti-IL-6 antibody. These results suggest that rhIL-11 acts directly as a megakaryocyte potentiator and may play a role in regulating human megakaryocytopoiesis.

Antigens, CD↗
PubMed1992

Granular lymphocyte leukemia with pure red cell aplasia: usefulness of gene analysis in assessing therapeutic effect.

A patient with granular lymphocyte leukemia (GLL) of the CD3+, CD4-, CD8+ phenotype accompanied by pure red cell aplasia (PRCA) is described. Surface marker analysis, nonmajor histocompatibility complex (MHC)-restricted cytotoxicity assay, gene analysis, and in vitro colony assay were performed on the granular lymphocytes before and after treatment. Cyclophosphamide therapy was highly effective, and after remission clonal granular lymphocytes were no longer identified by T-cell antigen receptor (TCR) gene analysis or surface marker analysis. Lymphocytes obtained after remission did not exhibit elevated levels of non-MHC-restricted cytotoxicity, nor did they demonstrate a suppressive effect on erythroid colony formation. TCR gene analysis proved to be a sensitive parameter for evaluating the residual malignant granular lymphocytes. Gene analysis will be useful both for timing the discontinuation of treatment and for the early detection of relapse. Various factors possibly related to the development of PRCA in this patient were investigated and their significance is discussed.

Bone Marrow↗