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K Odaka

Publications and source records attributed to K Odaka.

At least 37 records · Page 2Linked to original sources
PubMed1985

Effect of activated lymphocytes on the regulation of hematopoiesis: suppression of in vitro granulopoiesis and erythropoiesis by OKT8+ Ia- T cells induced by concanavalin-A stimulation.

The effects of activated lymphocytes were studied in the regulation of in vitro hematopoiesis. Peripheral blood lymphocytes stimulated by concanavalin A (Con A) were cocultured with normal bone marrow cells in the assay system of hematopoietic stem cells. Con-A-stimulated lymphocytes and their supernatants showed significant suppression of in vitro growth of myeloid and erythroid progenitor cells (CFU-C, CFU-E, and BFU-E). Suppressive activity detected in the T-cell fraction was completely abolished by treatment with OKT3 or OKT8 monoclonal antibody and complement and 20 Gy radiation but not OKT4 or OKIa1 antibody and complement. These observations indicate that peripheral blood lymphocytes can be induced by Con-A stimulation to become suppressor T cells for myeloid and erythroid progenitor cells that are OKT8 positive, Ia negative, and radiosensitive. Together with our previous observation that CFU-C suppressor cells induced by alloantigen stimulation are radioresistant and OKT8- and Ia-positive T cells, it is suggested that in vitro hematopoiesis may be regulated by heterogeneous subpopulations of activated T-lymphocytes.

Antibodies, Monoclonal↗
PubMed1985

Immunological reconstitution after allogeneic and autologous bone marrow transplantation.

Immunological reconstitution was studied with regard to T cell subsets and their functions in patients who received intensive therapy and autologous or allogeneic marrow transplantation. One of the distinct features was the imbalance of T cell subsets. Long-standing inversion of the OKT4/OKT8 ratio was characteristic in both autotransplant and allotransplant patients. Significant differences were observed in recovery of T cell subsets and mitogenic responses between autotransplant and allotransplant patients and between transplant patients and normal controls. In contrast, low reactivities of mixed lymphocyte culture (MLC) recovered to normal levels within 1 yr in both groups of patients. Then the role of suppressor cells was investigated. During early posttransplant periods, MLC suppressor cells were operative in association with the development of low MLC reactivities because suppressor activity was inversely correlated with MLC reactivities at a significant level. Characterization of these MLC suppressor cells revealed that they were an OKT8- and Ia-positive, radioresistant T cell subset of peripheral blood lymphocytes from autologous and allogeneic marrow recipients. These observations suggest that the imbalance of T cell subsets and their abnormal reactivities may by responsible for the development of immunodeficiency and immunodysregulation in bone marrow transplant patients.

Antibodies, Monoclonal↗
PubMed1984

T lymphocyte reconstitution in long-term survivors after allogeneic and autologous marrow transplantation.

T cell subsets and their immune reactivities were studied in long-term survivors after bone marrow transplantation and the results of autotransplanted and allotransplanted patients were compared. These two groups of patients (4 autotransplants and 4 allotransplants) were roughly comparable in terms of their underlying diseases, pretransplant conditioning regimens, supportive care, and posttransplant sampling days for immunological studies. Significant differences were observed between autologous and allogeneic marrow recipients in the total number of OKT3-, OKT4-, OKT8-, and OKIa1 -positive cells. Similar differences were observed between transplant patients and normal controls. Decreased OKT4 cells and increased OKT8 cells resulted in inversion of the OKT4:OKT8 ratio, which was significantly lower in allotransplanted compared with autotransplanted patients, and both groups of transplant patients showed depressed responses in comparison with normal controls. In contrast, there were no significant differences in MLR reactivities between transplanted patients and normal controls. When mitogenic responses were analyzed in relation to T cell subsets, phytohemagglutinin responsiveness showed a significant correlation with OKT4:OKT8 ratios (P less than 0.01) and the proportions of cultured OKT4 cells (P less than 0.01). These observations suggest that T lymphocyte reconstitution is still incomplete or abnormal in long-term survivors regardless of the type of graft. Furthermore, abnormalities observed in these long-term survivors were characterized by an imbalance of T cell subsets that was more profound in allotransplanted than in autotransplanted patients.

Adolescent↗
PubMed1984

Effect of activated lymphocytes on the regulation of hematopoiesis: suppression of in vitro granulopoiesis by OKT8+Ia+T cells induced by alloantigen stimulation.

We studied the effects of alloantigen-stimulated lymphocytes in the regulation of hematopoiesis. Alloantigen-stimulated lymphocytes were harvested on days 2 to 3, days 6 to 7, or days 9 to 10 of MLC and were tested for their effects on granulocyte/macrophage progenitor cells (CFU-C). Dose-dependent suppression of CFU-C was observed when alloantigen-stimulated lymphocytes from days 6 to 7 and days 9 to 10 MLC were added to the cultures of autologous or allogeneic bone marrow cells for CFU-C assays. Suppressive activity was detected in the T cell fraction but not in the non-T cell fraction. For further characterization of these CFU-C/suppressor cells, alloantigen-stimulated lymphocytes were treated with radiation (2000 rad) or with monoclonal antibodies against T cell subsets and complement (C) before culture. Suppressive activity was completely abolished by treatment with OKT8 or OKIa1 antibodies and C whereas suppression was retained after radiation treatment. These observations suggest that CFU-C/suppressor cells can be induced by alloantigen stimulation in MLC and that they are radioresistant OKT8+ and Ia+ T cells.

Antibodies, Monoclonal↗
PubMed1984

Controlled study of therapeutic granulocyte transfusions in granulocytopenic patients with severe infections.

The effectiveness of therapeutic granulocyte transfusions was studied in a controlled trial involving 75 granulocytopenic patients with severe infections. Patients who had granulocyte counts of less than 200/mm3 and no response to antibiotic therapy were assigned to receive antibiotic therapy alone or granulocyte transfusions plus antibiotic therapy. Granulocytes were collected by filtration leukapheresis (FL), intermittent flow centrifuge leukapheresis (IFCL) or continuous flow centrifuge leukapheresis (CFCL). Therapeutic effects of granulocyte transfusions were evaluated on the basis of 20-day survival after entry into the study. The patients were divided into three groups: 1) 22 patients received antibiotic therapy alone for 29 infectious episodes (control group); 2) 27 patients received 131 transfusions of granulocytes collected by FL for 31 infectious episodes (FL group); 3) 26 patients received 139 transfusions of granulocytes collected by IFCL and CFCL for 27 infectious episodes (IFCL & CFCL group). The overall survival of the transfused patients was not significantly different from that of the untransfused patients. Similarly, there was no significant difference in survival between the transfused and untransfused patients when the data concerning septicemia were analyzed. When patients showed bone-marrow recovery, which was indicated by recovery of granulocytes to 500/mm3 or more during the study, 20-day survival was observed in 13 of 14 untransfused patients and in all of 26 transfused patients. In contrast, the survival rate for the patients without bone-marrow recovery was 13% (2/15) in the control group, 39% (7/18) in the FL group and 57% (8/14) in the IFCL & CFCL group respectively. Thus, the survival rate was significantly higher for the transfused than for the untransfused patients. These observations suggest that therapeutic granulocyte transfusions may be of limited value in improving the outcome of severe infections in persistently granulocytopenic patients. Since bone-marrow recovery is a critical factor for the prognosis of severe infections, therapeutic granulocyte transfusions do not provide any beneficial effects in granulocytopenic patients whose bone-marrow function will recover.

Adolescent↗
PubMed1983

[Autologous bone marrow transplantation in the treatment of nasopharyngeal carcinoma--report of 2 cases].

Two patients with nasopharyngeal carcinoma (NPC) were treated with "marrow-lethal" chemoradiotherapy and infusion of cryopreserved autologous marrow. Patient AUT 04 (unique patient number), a 28-year-old male, was referred to us because of the right cervical lymphadenopathy. He was diagnosed NPC at stage II (T1N2M0). A trial of combined-modality therapy using autologous bone marrow transplantation (auto-BMT) was scheduled for possible cure. Before auto-BMT, he was treated with a conventional dose of radiation to the nasopharyngeal and bilateral cervical areas. For the pretransplant marrow-lethal therapy, he received high-dose cyclophosphamide (CY), 120mg/kg, and 1,000 rad total body irradiation (TBI). Within 24 hr after TBI, previously cryopreserved-thawed autologous bone marrow cells (1.37 X 10(8)/kg) was infused to the patient. Rapid and complete hematologic recovery was observed and he is now alive in a disease-free remission state 28 months after transplantation. Patient AUT 08, a 18-year-old female, was referred to us for the treatment of head and neck tumor with auto-BMT. She was diagnosed NPC at stage IV (T4N2M0). After cryopreservation of bone marrow, she was treated with local radiation and doxorubicin (80mg X 2d). Then she was conditioned with high-dose CY and upper half body irradiation and received auto-BMT (marrow dose: 1.2 X 10(7)/kg). Successful engraftment was obtained with tumor response but she developed recurrence of the disease 12 months after transplantation. Although the data are too preliminary, auto-BMT is evaluated as one of the favorable treatment approaches for some selected patients with NPC.

Adolescent↗