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Biomedical subjects

H Tezuka

Publications and source records attributed to H Tezuka.

At least 55 records · Page 3Linked to original sources
PubMed1988

Establishment and characterization of a transplantable erythroblastic leukemia in C3H mice.

A disease with the characteristics of an erythroblastic leukemia was induced by X-ray irradiation of 300 Rads in C3H mice. The leukemia is transplantable in syngeneic mice by i.v. injection of the spleen cells. The mice show almost pure erythroid cells of various differentiation stages in peripheral blood. The number of total nucleated cells in the peripheral blood increased, but hematocrit and platelet number decreased. Reverse transcriptase activities were measured in spleen and liver of the mice and the data suggested that the leukemia was not induced by retrovirus infection. This leukemia is distinguishable, in this respect, from diseases reported by Friend or Rauscher. The leukemia will offer a good animal model for the studies on non-viral leukemogenesis and disorders of erythropoiesis.

Animals↗
PubMed1988

Stromal cell-dependent growth of leukemic cells from murine erythroblastic leukemia.

Transplantable erythroblastic leukemia was induced by 300-rad irradiation of C3H mice. Conditions for in vitro growth of the leukemic cells were studied. None of interleukin-3, granulocyte/macrophage colony-stimulating factor and erythropoietin could support the growth of the cells in vitro. In contrast, the leukemic cells grew into a stroma-dependent cell line, ELM-D, in close contact with the stromal cell layer of 900-rad-irradiated long-term bone marrow culture. A stroma-independent cell line, termed ELM-I-1, was further established from the non-adherent population in the co-culture of the leukemic cells, ELM-D, with stromal cells. Reverse transcriptase activity was not detectable in ELM-D or ELM-I-1 cells. Studies on binding and cross-linking of 125I-erythropoietin showed that ELM-I-1 cells had erythropoietin receptors, and two major radiolabeled protein products with molecular weights of 120 kDa and 140 kDa were detected on sodium dodecyl sulfate/polyacrylamide gel electrophoresis under reducing conditions.

Animals↗
PubMed1988

Natural killer and natural killer-like cell activity of peripheral blood and intrathyroidal mononuclear cells from patients with Graves' disease.

This study was undertaken to investigate the natural killer (NK) and natural killer-like (NK-like) cell cytotoxic activity toward autologous thyrocytes of peripheral blood mononuclear cells (PB-MNC) and thyroid gland mononuclear cells (TG-MNC) from previously hyperthyroid patients with Graves' disease, and the effects of recombinant interleukin-2 on such cytotoxic activity. The average cytotoxicities of PB-MNC from Graves' patients toward K562 cells (NK-sensitive cells), Raji cells (NK-resistant cells), and autologous thyrocytes were 23.9 +/- 10.8 (+/- SD) lytic units (LU), 7.4 +/- 3.8 LU, and 11.7 +/- 4.4 LU, respectively. There were no differences in the NK and NK-like cell activity of PB-MNC between Graves' disease patients and normal subjects. In contrast to PB-MNC from patients with Graves' disease, NK and NK-like cell activity was markedly decreased in TG-MNC (NK cell activity, 2.1 +/- 2.3 LU; NK-like cell activity, 1.5 +/- 1.5 LU). TG-MNC from Graves' patients had no cytotoxic activity against autologous thyrocytes. Using the monoclonal anti-Leu 7 and anti-CD16 antibodies and a two-color immunofluorescence method, the NK cell subsets were examined in PB-MNC and TG-MNC from Graves' patients. The percentage of CD16+ cells was significantly decreased in TG-MNC compared to PB-MNC, whereas there was no significant difference in the percentage of Leu 7+ cells between PB-MNC and TG-MNC. Incubation of TG-MNC with medium only did not increase the NK and NK-like cell activity of these cells. Furthermore, incubation of autologous PB-MNC with supernatants of minced thyroid tissues did not alter their NK and NK-like cell activity. The decreased NK and NK-like cell activity of TG-MNC was augmented when these cells were incubated with recombinant interleukin-2. These results suggest that the reduction of NK cell activity in TG-MNC may allow perpetuation of B-cell activation and lead to excessive production of autoantibody in thyroid tissue.

Adolescent↗
PubMed1988

Phenotypic analyses and concanavalin-A-induced suppressor cell dysfunction of intrathyroidal lymphocytes from patients with Graves' disease.

The expression of phenotypic markers and Concanavalin-A-induced suppressor activity was compared among mononuclear cells isolated from thyroid glands and peripheral blood of thionamide-treated patients with hyperthyroid Graves' disease and peripheral blood from normal subjects. Intrathyroidal lymphocytes were obtained by two different methods (TG-1 and TG-2 cells), gradient centrifugation of supernatants of minced thyroid tissue and overnight culture of thyroid debris after mechanical disaggregation and enzymatic digestion, respectively. The percentages of CD3+ cells (all mature T cells) among peripheral blood and TG-1 and TG-2 cells from Graves' patients were similar, but the percentages of B1+ cells (pan B cells) among the TG-1 and TG-2 cells were markedly increased compared to that in peripheral blood. The percentages of CD4+ cells among the TG-1 and TG-2 cells were significantly less than that in peripheral blood. The percentages of CD4+2H4+ cells among CD4+ cells in TG-1 and TG-2 cells also were significantly less than that in peripheral blood. The percentage of CD4+4B4+ cells among CD4+ cells in thyroid glands was markedly higher than that in peripheral blood. The percentages of CD8+ cells and CD8+CD11b- cells (cytotoxic T cells) in thyroid glands were significantly higher than those in peripheral blood from Graves' patients and peripheral blood from normal subjects. The CD8+CD11b+ cells were subdivided into two subpopulations on the basis of CD8 antigen density. The percentage of dull CD8+CD11b+ cells (natural killer cells) among TG-2 cells was lower than that in peripheral blood, but there was no significant difference in bright CD8+CD11b+ cells (suppressor-effector T cells) between thyroid glands and peripheral blood. The percent suppression induced by Concanavalin-A in both TG-1 and TG-2 cells was significantly decreased compared with that in peripheral blood. These results suggest that impairment of suppressor cell activity and an increased number of B cells exist in thyroid glands of patients with Graves' disease compared to those in peripheral blood. It, thus, appears likely that both B cell hyperactivity and suppressor T cell dysfunction may induce excess production of autoantibodies in the thyroid glands of such patients.

Adolescent↗
PubMed1988

In vitro cellular interactions among thyrocytes, T cells and monocytes from patients with Graves' disease.

In order to investigate the cellular interactions among thyrocytes, T cells and monocytes in thyroid glands from patients with Graves' disease, we determined alterations of HLA-DR antigen expression on thyrocytes and T cells, and the production of interferon-gamma during coculture of thyrocytes, T cells and monocytes obtained from patients with Graves' disease. Thyroid glands were obtained at operation from 17 patients with Graves' disease. When thyrocytes and autologous peripheral blood T cells were cocultured for 7 days, the percentage of HLA-DR antigen expression on thyrocytes was significantly increased by T cells and that on T cells was also significantly increased by thyrocytes. Addition of autologous monocytes to the mixtures of thyrocytes and T cells significantly increased the expression of HLA-DR antigens on both thyrocytes and T cells compared with mixtures without monocytes. In culture supernatants, interferon-gamma was detected in 4 of 14 cocultures of thyrocytes and T cells, in 5 of 10 cocultures of thyrocytes, T cells and monocytes, but not in any cultures of thyrocytes alone, T cells alone and T cells and monocytes. Induction of HLA-DR antigen expression on thyrocytes and T cells was blocked by addition of anti-interferon-gamma monoclonal antibody to the mixture. These results suggest that HLA-DR antigen positive thyrocytes are able to induce the HLA-DR antigen expression of T cells in the presence of monocytes, and the activated T cells are capable of producing interferon-gamma which acts on thyrocytes to induce and maintain the expression of HLA-DR antigens.

Adolescent↗
PubMed1988

The effects of cytokines, antithyroidal drugs and glucocorticoids on phagocytosis by thyroid cells.

The present study was undertaken to examine whether thyrocytes possess phagocytic activity and whether the phagocytic activity is influenced by cytokines, such as interleukin 1, 2 (IL 1, IL 2) and interferon-alpha, -beta, and -gamma (IFN-alpha, beta, and gamma), and drugs, such as methimazole and dexamethasone. Thyroid glands were obtained from patients with Graves' disease. Thyrocytes were prepared by collagenase digestion. Thyrocytes were pre-incubated in the presence or absence of cytokines and drugs at 37 degrees C for 20 h and were further incubated with fluoresceinated latex beads at 37 degrees C for 60 min. The number of phagocytic thyrocytes was determined by FACS IV. Phagocytosis of latex beads was indeed seen within thyrocytes and gradually increased in a time-dependent manner. The rate of phagocytosis in thyrocytes was extremely slow as compared with that in macrophages. Phagocytic activity was detected in thyrocytes from patients with Graves' disease and from normal thyroid tissue adjacent to thyroid cancer. Phagocytosis was inhibited by IL 1, but was enhanced by IL 2. Although the enhanced phagocytosis with IFN-beta was consistently seen, little effect was detected with IFN-alpha and -gamma. Both methimazole and dexamethasone markedly inhibited phagocytosis. These results indicated that thyrocytes had phagocytic properties and that their phagocytic activity was modulated by cytokines, antithyroidal drugs and dexamethasone.

Antithyroid Agents↗
PubMed1988

Clonal assay of mast cell progenitors in semi-solid culture with a high seeding efficiency.

In vitro clonal assay of murine mast cell progenitors was examined in semi-solid culture by using conditioned medium of a murine leukemic T-cell line (STIL-3) as the source of interleukin 3 (IL-3). In soft agar gel, mast cell colonies were formed with a seeding efficiency of 100-200 per 10(5) bone marrow cells, which was much higher than previously reported data. Macrophages were distinguishable from mast cells by their characteristic "foamy" appearance in toluidine blue and May-Grünwald-Giemsa stained preparations and by their capacity to phagocytize carbon particles. Thus, the present method may provide a sensitive assay technique for the quantitative evaluation of mast cell progenitors.

Animals↗
PubMed1988

[A case of adrenal myelolipoma].

We report a case of surgically resected adrenal myelolipoma. Myelolipoma of the adrenal gland is a rare, benign and nonfunctioning tumor. The present patient represents the 57th reported clinical case of this tumor. It consists of fatty and hematopoietic tissue. It is asymptomatic and usually found only at autopsy incidentally. Ultrasonography, computed tomography and fine needle biopsy help in the preoperative diagnosis of adrenal myelolipoma. Especially fine needle biopsy is recommended when the diagnosis is doubtful.

Adrenal Gland Neoplasms↗
PubMed1988

Synergy in antigen presentation by thyroid epithelial cells and monocytes from patients with Graves' disease.

The present study was undertaken to examine the ability of thyrocytes from Graves' patients to present purified protein derivative (PPD) to autologous peripheral blood T cells. Normal human thyrocytes which were pre-cultured with interferon-gamma were able to induce the proliferation of T cells in response to PPD antigen, but unstimulated thyrocytes failed to do. Thyrocytes from Graves' patients on which HLA-DR antigens were expressed have an ability to induce the proliferation of T cells. Thyrocytes from Graves' patients which were pulsed with PPD antigen for 4 h were capable of stimulating proliferation of the T cells. However, the stimulation index of T cells co-cultured with thyrocytes and PPD were significantly lower than that of T cells co-cultured with monocytes and PPD. Sub-optimal numbers of monocytes which by themselves were unable to support T-cell proliferation synergistically augmented antigen presentation by thyrocytes. These results suggest that cellular interactions among thyrocytes, monocytes and T cells may perpetuate immune or autoimmune responses in thyroid tissues from Graves' patients.

Adolescent↗
PubMed1988

Competitive induction of erythroid progenitors by relative concentration of BPA to erythropoietin: possible existence of intermediate compartment between BFU-E and CFU-E.

Crude preparations of erythropoietin (Epo) have been found to contain burst-promoting activity (BPA) as a contaminant. When anti-Epo antiserum was added to the culture of erythroid progenitor cells stimulated in vitro with crude Epo, the number of colonies derived from late erythroid progenitors (CFUe) was reduced, while that from early erythroid progenitors (BFUe) was increased. On the other hand, when the culture was stimulated with BPA-free Epo, which was purified from human urine, addition of anti-Epo antiserum enhanced neither BFUe nor CFUe. These results suggest that the ratio of BPA and Epo may be crucial in the assay of erythroid progenitors. Addition of anemic mouse spleen-conditioned medium (AMSCM) to the culture as a source of BPA resulted in the increase of BFUe and the reduction of CFUe under various concentrations of Epo. These findings might be explained by the existence of intermediate compartment of erythroid progenitors depending on both BPA and Epo.

Animals↗
PubMed1988

Suppression of genetic resistance to bone marrow grafts and natural killer activity by administration of fat emulsion.

Graft rejection is one of the major obstacles to successful bone marrow transplantation (BMT). If resistance to marrow grafting could be avoided, BMT could be used widely in treatment of hematological and immunological disorders. There has been evidence that natural killer (NK) cells play a major role in genetic resistance to BMT and that macrophages are also involved in genetic resistance. Agents toxic to macrophages such as silica and carrageenan have been found to have a suppressive effect on genetic resistance to BMT. Parenteral fat emulsions are known to accumulate in macrophages and to impair various functions of macrophages and those of the reticuloendothelial system. We show here that the administration of a fat emulsion, Intralipos 20%, to recipient mice can suppress genetic resistance to bone marrow grafts and NK cell activity probably through the impairment of the macrophage function. The administration of the fat emulsion might be a new tactic in conditioning protocols for human BMT in the future.

Animals↗
PubMed1987

Maintenance of granulopoiesis in long-term bone marrow cultures from W/Wv mice and effects of lipopolysaccharide on granulopoiesis in culture.

An attempt was made to establish long-term cultures of marrow cells from genetically anaemic W/Wv mice. Two batches of horse sera were used. One batch of horse serum (HS-lot A) supported long-term maintenance (up to 20 weeks) of granulopoiesis in vitro. The number of suspension cells in W/Wv marrow culture was maintained at the same level as that in the control +/+ culture, but the number of granulocyte-macrophage progenitor cells (GM-CFC) and the ratio of immature to mature granulocytes were at a lower level than those in +/+ culture. These data suggest that haemopoietic progenitors in W/Wv cultures maintain a higher level of differentiation, and hence an increased self-renewal than those in +/+ cultures. Another batch of horse serum (HS-lot B) was less effective in the maintenance of the cultures, and the cultures deteriorated within 10 weeks. Addition of bacterial lipopolysaccharide (LPS) induced increased granulopoiesis in +/+ cultures, whereas such treatment resulted in the depletion of suspension cells in W/Wv cultures. The results suggest that haemopoietic cells of W/Wv mouse cannot cope with the strong stimulus for differentiation that occurs after the administration of LPS, although the cells can continue a moderately increased self-renewal and differentiation, as indicated by the results in the culture with HS-lot A.

Anemia, Macrocytic↗
PubMed1987

Reduction in the suppressor-inducer T cell subset and increase in the helper T cell subset in thyroid tissue from patients with Graves' disease.

The expression of surface markers associated with activation and characterization was compared among T cells in thyroid glands and peripheral blood of 10 patients with Graves' hyperthyroidism receiving chronic antithyroid drug therapy, in peripheral blood of 15 patients with untreated hyperthyroid Graves' disease, and in peripheral blood of 21 normal subjects using two-color flow cytometry. In the chronically treated Graves' disease patients, the percentage of activated T cells (HLA-DR+ T cells) among total T cells was significantly higher in thyroid tissue than in peripheral blood, and the increase in percent activated T cells was also significant among both helper/inducer T cell (CD4+ cell) and suppressor/cytotoxic T cell (CD8+ cell) subsets. The percentage of activated T cells in peripheral blood was not significantly different between chronically treated hyperthyroid Graves' patients and normal subjects, whereas the percentage of activated T cells in the peripheral blood from untreated hyperthyroid Graves' disease patients was significantly higher than that in normal subjects or chronically treated hyperthyroid Graves' patients. The percentages of CD4+ cells and CD8+ cells among total T cells were not different between thyroid tissues and peripheral blood in patients with chronically treated hyperthyroid Graves' disease. When CD4+ were further divided into helper T cells (CD4+2H4- cells) and suppressor-inducer T cells (CD4+2H4+ cells) using two-color flow cytometry, the percentage of helper T cells among CD4+ cells was significantly higher in thyroid tissue than in peripheral blood, resulting in an increased ratio of CD4+2H4- cells to CD4+2H4+ cells. The percentage of CD4+2H4+ cells in peripheral blood, however, was not significantly different among untreated and chronically treated Graves' disease patients and normal subjects. From the findings of abnormalities in intrathyroidal T cell subsets, we suggest that the decrease in the function of suppressor T cells within the thyroids of Graves' disease patients may be due to a decrease in CD4+2H4+ cells within thyroid tissue.

Adolescent↗
PubMed1987

Dysfunction of suppressor T cells in thyroid glands from patients with Graves' disease.

To investigate the suppressor function of intrathyroidal (TG) T cells in Graves' disease, the percentage of suppressor T cell subsets and the suppressor function of TG and peripheral blood (PB) lymphocytes in Graves' disease were compared by determining the in vitro production of immunoglobulin G (IgG) in reconstituted mixtures of separated B, CD4+ (helper/suppressor-inducer T), and CD8+ (suppressor/cytotoxic T) cells. TG lymphocytes were obtained by gradient centrifugation of the supernatants of minced thyroid tissues. T Cells were separated by E-rosette formation, and CD4+ and CD8+ cell-rich populations were separated by a panning method using monoclonal anti-CD8 antibody. Mixtures of 5 X 10(4) B (PB1 or TG) cells, 2 X 10(4) CD4+ (PB or TG) cells, and 5 X 10(3) macrophages (PB or TG) were cultured with various numbers of CD8+ (PB) or CD8+ (TG) cells for 7 days with pokeweed mitogen, and IgG synthesis was determined by solid phase RIA. T cell subpopulations were quantitated by a direct immunofluorescence method using monoclonal anti-CD3, anti-CD4, and anti-CD8 antibodies. There was no difference in the percentages of CD8+ cells among total T cells between thyroid glands and peripheral blood from Graves' disease patients [mean PB, 39.8 +/- 9.8% (+/- SD); TG, 42.5 +/- 13.8%; n = 10]. IgG production by mixtures of B and CD4+ cells isolated from peripheral blood was not different from that by cells isolated from thyroid glands [mean PB, 1635 +/- 248 (+/- SE) ng/mL; TG, 1081 +/- 128 ng/mL; n = 19; P = NS]. The nonspecific suppressor activity of thyroid gland CD8+ cells was less than that of CD8+ (PB) cells [percent suppression of IgG production by mixtures of B (PB) and CD4+ (PB) cells, 12.5% vs. 57.0% (P less than 0.01); by mixtures of B (TG) and CD4+ (TG) cells, 5.8% vs. 38.9% (P less than 0.01)]. The suppressor-inducer function of CD4+ (TG) cells was also decreased compared with that of CD4+ (PB) cells. These results suggest that the impairment of suppressor cell activity may lead to excessive production of autoantibody in thyroid glands from patients with Graves' disease.

Adult↗
PubMed1987

The remarkable proliferation of helper T cell subset in response to autologous thyrocytes and intrathyroidal T cells from patients with Graves' disease.

We have studied cellular interactions among thyrocytes, intrathyroidal T cells and peripheral blood T cells from Graves' patients. In the autologous mixed lymphocyte reaction of Graves' patients, CD4+ cells were able to proliferate vigorously against autologous non-T cells, whereas CD8+ cells responded weakly to non-T cell stimulators. Furthermore, the proliferative response of the CD4+ 2H4+ suppressor-inducer T cell subset was increased like that of the CD4+ 2H4- helper T cell subset. In contrast to peripheral blood non-T cell stimulators, thyrocytes and intrathyroidal T cells had the ability to activate the CD4+ 2H4- helper T cell subset but were not able to cause proliferation both of CD4+ 2H4+ suppressor-inducer T cell and CD8+ suppressor/cytotoxic T cell subsets. The marked reduction in proliferative responses of CD4+ 2H4+ cells and CD8+ cells could not be attributed to a difference in kinetics or altered response to variable number of stimulator cells. On the basis of these findings, it is suggested that the concentration of the helper T cell subset may be progressively increased and suppressor circuits may be unable to be activated in thyroid tissues. These abnormalities in cellular interactions may induce the excessive production of autoantibodies.

Adolescent↗