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S Tohda

Publications and source records attributed to S Tohda.

At least 55 records · Page 3Linked to original sources

Comparative effects of busulfan, cytosine arabinoside and adriamycin on different maturation stages of normal human bone marrow cells.

Leukemic blast progenitors in acute myeloblastic leukemia (AML) undergo terminal divisions and/or self-renewal, which can be studied by the methylcellulose culture method and suspension culture, respectively. Using these methods, we have shown that busulfan (BU) was more effective against the self-renewal of blast progenitors than against the terminal divisions. As reported previously, cytosine arabinoside (Ara-C) is more effective against self-renewal and adriamycin (ADR) is more effective against terminal divisions. To determine the reason why antileukemic drugs show different sensitivity against self-renewal and terminal divisions, we studied the effects of these drugs on normal human bone marrow cells. We have shown that BU and Ara-C suppressed the colony formation induced by interleukin-3 (IL-3) more effectively than that by granulocyte colony-stimulating factor (G-CSF). On the other hand, ADR suppressed the colonies induced by G-CSF more effectively. In normal hemopoiesis, IL-3 has been shown to stimulate the growth of more primitive hemopoietic stem cells, while G-CSF has been documented to stimulate the growth of granulopoietic committed precursors at a more differentiated stage. Therefore, BU and Ara-C are considered to be more effective against the immature cells in normal bone marrow and ADR is effective against the more differentiated cells. We suppose that the different differentiation stage of target cells may explain the difference of the effects on self-renewal and terminal divisions between BU, Ara-C and ADR.

Bone Marrow↗

Effect of platelet-derived growth factor on the proliferation of blast progenitors from acute myeloblastic leukemia patients.

The effect of platelet-derived growth factor (PDGF) on self-renewal and terminal divisions of blast progenitors of acute myeloblastic leukemia was studied. The terminal divisions of blast progenitors were determined as the primary blast colony formation in methylcellulose culture; self-renewal was assessed by secondary colony formation by replating in methylcellulose and the recovery of clonogenic cells in suspension culture. PDGF neither enhanced nor suppressed primary or secondary blast colony formation in methylcellulose culture nor recovery of clonogenic cells in suspension. The results show that PDGF does not affect the self-renewal or terminal divisions of leukemic blast progenitors.

Adolescent↗

Role of humoral and cellular factors on the growth of blast progenitors of acute myeloblastic leukemia in serum-free culture.

To determine the growth requirement of leukemic blast progenitors in acute myeloblastic leukemia (AML), leukemic cells from the peripheral blood of eight AML patients were cultured in the serum-free culture system. Blast progenitors made colonies in methylcellulose culture and showed exponential growth in suspension culture, although the growth of blast progenitors in the absence of fetal calf serum (FCS) in some patients was inferior to that in the FCS-enhanced culture system. Recombinant human granulocyte colony-stimulating factor (rhG-CSF) stimulated the growth of blast progenitors in a dose-responsive manner. When cells were cultured at high cell density, blast colonies were formed even in the absence of CSF. Irradiated blasts also supported the growth of intact blast progenitors. These results confirm the finding noted in the FCS-enhanced culture studies that granulopoietic factor, G-CSF, plays an important role on the leukemic growth. The importance of cell to cell interaction for the growth of blast progenitors was also confirmed.

Blast Crisis↗

Terminal differentiation to mature neutrophils and eosinophils in suspension culture of the blast progenitors in acute myeloblastic leukemia.

The blasts obtained from three freshly diagnosed acute myeloblastic leukemia (AML) patients were cultured in suspension to determine whether leukemic blast progenitors can indeed differentiate to form mature granulocytes. One patient was AML M2. The other two patients were bilineal and biphenotypic leukemia, respectively. Media conditioned by human bladder carcinoma line 5637 (5637-CM) or recombinant human granulocyte colony-stimulating factor (rhG-CSF) was added to stimulate growth. In suspension, clonogenic cells grew for 1-3 weeks in two patients, while they did not increase in one patient. After repeated subculture, cells of blast morphology decreased in percentage and polymorphonuclear neutrophils, eosinophils, and monocyte-macrophages appeared. Lymphoid cell component of the patient 2, who was diagnosed as bilineal leukemia by dual-color immunofluorescence analysis, decreased in number after suspension culture and cells of myeloid phenotype became dominant. The findings show that clonogenic blast progenitors can renew themselves and can also undergo terminal differentiation to mature end cells.

Adult↗

Haematopoietic suppressing activity of gamma-interferon in serum and bone marrow of aplastic anaemia patients.

To determine the mechanism by which haematopoiesis is suppressed in aplastic anaemia, the effect of the sera from 6 patients on the granulopoietic precursors (colony-forming units in culture; CFU-C) was studied in vitro. Addition of the sera from 2 patients significantly suppressed CFU-C. The suppressive effect of the sera on CFU-C was inhibited by the addition of 1.5 NU/ml of anti-gamma-IFN antibody. In another patient, anti-gamma-IFN antibody increased autologous CFU-C although the serum of the patient did not suppress CFU-C. Serum gamma-IFN levels of all patients were under 2 IU/ml. The above findings suggest that humoral factors inhibit haematopoiesis in some patients with aplastic anaemia, and that gamma-IFN plays a role as an inhibitor even at a low concentration.

Adolescent↗

[Acute myeloblastic leukemia and hepatocellular carcinoma following Waldenström's macroglobulinemia].

A 54-year-old man was admitted to our hospital for precise examination of pancytopenia in October 1988. He had been cut off his left femur and irradiated because of osteosarcoma in 1954. After 30 years, he was diagnosed as Waldenström's macroglobulinemia. Melphalan had been given 2 mg daily for 19 months until August 1988, when it was discontinued due to pancytopenia. Peripheral blood showed Hb 6.6 g/dl, platelet 40 x 10(3)/microliters, and WBC 2000/microliters with 33% blasts. Bone marrow showed normocellularity with 36% blasts. Although blasts were negative for peroxidase staining, surface marker analysis revealed myeloid (CD 13, CD 33) phenotypes. Chromosome analysis showed 45, XY, -7, inv (3). A CT scan of the liver showed a mass, 10 by 10 cm, compatible with hepatocellular carcinoma. He was treated with very low dose Ara-C without noticeable effect. Hepatic tumor gradually enlarged, and he died of hepatic failure. This is a rare case of quadruplicate malignancies. The chromosomal abnormality suggests that AML was secondary leukemia which might be associated with immunosuppression due to macroglobulinemia and/or melphalan therapy.

Carcinoma, Hepatocellular↗

Mechanism of action of interleukin 1 on the progenitors of blast cells in acute myeloblastic leukemia.

We tested the effect of interleukin 1 (IL-1) on the growth of leukemic blast progenitors from patients with acute myeloblastic leukemia (AML). A purified blast cell fraction depleted of both T cells and phagocytic cells was tested at different cell densities. Addition of 1 ng/ml of IL-1 alpha alone enhanced blast colony formation in 10 of 13 cases tested, and the enhancement was prominent when plated cell densities were lowered. The conditioned media (CM) from AML patients contained varied levels of IL-1 activity, and following depletion of phagocytic cells, the levels decreased markedly in all cases tested. Addition of either antiserum against IL-1 alpha or IL-1 beta reduced the IL-1 activity in CM, suggesting that AML blasts produce both IL-1 alpha and IL-1 beta. Addition of IL-1 alpha or IL-1 beta antiserum inhibited blast colony formation in a dose-dependent manner, and a combination of both antisera showed the most marked inhibition. However, the augmentation of blast colony formation was almost completely inhibited by addition of anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) serum in all three cases tested. IL-1 is also devoid of this activity when tested in the presence of a combination of granulocyte CSF (G-CSF), GM-CSF, and interleukin 3 (IL-3) at an optimal concentration. These results suggest that blast cells could produce and secrete CSF(s) and/or IL-1, and that the growth-enhancing effect of IL-1 on AML blasts is indirect, via production of CSFs by leukemic cells.

Colony-Stimulating Factors↗

Expression of interleukin 1 beta receptors on blast cells in acute myeloblastic leukemia: comparison with interleukin 1 beta proliferative activity.

We describe here the presence of a single class of interleukin 1 beta (IL-1 beta) receptors on the surface of blast cells freshly obtained from eight acute myeloblastic leukemia patients and one chronic myelocytic leukemia patient in blast crisis. Blast cells possessed a low number of high-affinity receptors (range, less than 10-173 receptors/cell) with a Kd of 1.8-12.8 x 10(-10) M. At the same time, we have investigated the effects of IL-1 on the growth of leukemic blast progenitors, and a significant heterogeneity of responsiveness was observed. IL-1 beta (1 ng/ml) enhanced blast colony formation in six patients. No significant effect was observed by addition of up to 100 ng/ml of IL-1 beta in the remaining three patients. No significant correlation was observed between the receptor number, receptor affinity, and the cellular responsiveness to IL-1; in some acute myeloblastic leukemia cases with apparent IL-1 receptors, no proliferation response to added IL-1 was observed. Our data show that IL-1 alone can enhance blast colony formation and that lack of responsiveness to IL-1 in some acute myeloblastic leukemia patients is not related to the absence of IL-1 receptors on blast cells.

Adult↗

Specific binding of radioiodinated human GM-CSF to the blast cells of acute myeloblastic leukemia.

We describe here the presence of two classes of binding sites for GM-CSF expressed on blasts freshly isolated from five AML patients and one patient with CML in blastic phase: one of high-affinity (38-177 per cell, KD 8-150 pM) and one of low-affinity (121-806 per cell, KD 503-2683 pM). No correlation is observed between the receptor number, receptor affinity, and the growth stimulatory effect of GM-CSF on leukemic blast progenitors. Blasts from two cases showed no or negligible response to GM-CSF but expressed comparable numbers of receptors when compared with the numbers expressed by the sensitive blasts. Our data suggest that significant proliferative effects of GM-CSF can occur at low levels of high-affinity receptor occupancy. Lack of responsiveness to GM-CSF in some AML patients is not correlated to the absence of GM-CSF receptors on leukemic cells. Reduction in the growth of blast progenitors at high concentrations of GM-CSF may be attributed to the differentiating activity of GM-CSF via low-affinity receptors on leukemic cells.

Binding, Competitive↗

Inhibition of the in vitro growth of blast progenitors from acute myeloblastic leukemia patients by transforming growth factor-beta (TGF-beta).

The effects of transforming growth factor-beta (TGF-beta) on the blast progenitors from nine acute myeloblastic leukemia patients were studied in methylcellulose and suspension cultures. Leukemic blast progenitors undergo terminal divisions with a limited differentiation in methylcellulose culture, making blast colonies. Blast progenitors can renew themselves. The self-renewal can be reflected by secondary colony formation after replating primary blast colonies in fresh methylcellulose media and by the exponential growth of clonogenic cells in suspension culture. TGF-beta suppressed primary and secondary colony-formation in methylcellulose culture. Furthermore, TGF-beta suppressed the recovery of clonogenic cells in suspension. The results indicate that TGF-beta is effective in inhibiting not only terminal divisions but also self-renewal of leukemic blast progenitors.

Adolescent↗

Autocrine growth mechanisms of the progenitors of blast cells in acute myeloblastic leukemia.

Autocrine growth mechanisms of leukemic blast progenitors in acute myeloblastic leukemia (AML) were investigated. Colony formation of leukemic blast progenitors was observed in 14 of 14 patients tested when purified blast cell fraction depleted of both T cells and monocytes was plated in methylcellulose without any colony-stimulating factor (CSF). However, there existed a minimal cell density required to initiate blast progenitor growth with marked patient-to-patient variation. To clarify the role of cell density on the spontaneous growth of blast progenitors, we tested whether leukemic cells produced and secreted some stimulatory humoral factor(s). Production of colony-stimulating activity (CSA) by blast cells was observed in 17 of 18 patients tested. Following further depletion of monocytes, the CSA levels decreased markedly in 14 patients, indicating that blast cells with monocytoid differentiation were responsible for CSA production. We also confirmed granulocyte colony-stimulating factor (G-CSF) and/or granulocyte macrophage-colony-stimulating factor (GM-CSF) production by leukemic blasts using specific immunologic assays. When leukemic cells were divided into nonadherent nonphagocytic cell fraction and adherent cell fraction, only nonadherent nonphagocytic cells showed clonogenecity and adherent blast cells lacked the colony-forming capacity. The results indicate that there are at least two blast cell subpopulations in AML: one is proliferating subpopulation with self-renewal capacity and the other is supporting subpopulation with functions such as CSF production. The quite intimate relationship between these two blast cell subpopulations in AML may play an important role on the growth of leukemic blast progenitors in vitro.

Adult↗

[Castleman's lymphoma associated with swelling of pancreas and pancytopenia].

A 73-year-old male was admitted because of slight fever. Systemic lymphadenopathy, polyclonal hypergammaglobulinemia, swelling of pancreas and submaxillary gland and progressing pancytopenia probably by immune mechanism were observed. Histological examination of lymph node showed no destruction of the structure and mild capillary proliferation in the follicle centers. Between follicles, many immunoblasts and mature plasma cells which were polyclonal and mild capillary proliferation were recognized. He was diagnosed as having multicentric Castleman's lymphoma. Administration of prednisolone 10 mg per day improved his symptoms and laboratory data. Then he has been followed up. Referring to the literatures, we discussed the relation between multicentric Castleman's lymphoma and the related diseases.

Aged↗

Effects of recombinant human tumor necrosis factor on the self-renewal capacity of leukemia blast progenitors in acute myeloblastic leukemia.

The effects of human recombinant tumor necrosis factor type alpha (rTNF alpha) on the blast progenitors from 14 acute myeloblastic leukemia (AML) patients and 1 chronic myelogenous leukemia patient in blastic crisis were studied in methylcellulose and suspension cultures. Blast progenitors renew themselves and/or undergo terminal divisions. Plating efficiency of primary colony formation (PE1) in methylcellulose, which is considered to reflect the terminal divisions of blast progenitors, was suppressed by rTFN alpha in a dose-dependent manner in all cases. Plating efficiency of secondary colony formation (PE2) and the recovery of clonogenic cells in suspension culture, which are considered to reflect the self-renewal capacity of blast progenitors, were also suppressed by rTNF alpha in a dose-dependent manner in almost all cases. rTNF alpha also inhibited both PE2 and clonogenic cells in suspension culture, even in relapsed AML patients who were very refractory to intensive chemotherapies. The results demonstrate that rTNF alpha inhibits not only terminal divisions but also the self-renewal capacity of leukemic blast progenitors. The finding that rTNF alpha suppressed the self-renewal capacity of leukemic blast progenitors proposes the utility of rTNF alpha to AML therapy.

Cell Division↗

Granulocyte colony-stimulating factor-dependent growth of an acute myeloblastic leukemia cell line.

We report herein the establishment and characterization of a granulocyte colony-stimulating factor (G-CSF)-dependent acute myeloblastic leukemia (AML) cell line. The cell line, designated as OCI/AML 1a, has been cultured in the presence of G-CSF and has shown exponential growth for over two years. The cells growing in suspension culture resembled myeloblasts on the basis of morphologic, cytochemical and surface phenotypic analyses. Other CSFs, interleukin-3 and granulocyte-macrophage colony-stimulating factor did not support the growth of OCI/AML 1a cells so well as G-CSF. The effect on the growth of OCI/AML 1a cells of G-CSF was almost completely abolished by neutralizing monoclonal anti-G-CSF antibody. These findings showed that OCI/AML 1a cells required G-CSF for growth. OCI/AML 1a cell line will be valuable for studies of the biological nature, proliferation and differentiation of leukemic cells. Furthermore, OCI/AML 1a cells should be useful for determining the mechanism by which G-CSF induces the growth of hemopoietic cells.

Blotting, Northern↗