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T Yokochi

Publications and source records attributed to T Yokochi.

At least 181 records · Page 10Linked to original sources

Experimental autoimmune hepatitis in mice after immunization with syngeneic liver proteins together with the polysaccharide of Klebsiella pneumoniae.

Experimental autoimmune hepatitis could be produced in SMA mice by monthly injections of syngeneic liver homogenate or liver-specific lipoprotein together with the polysaccharide of Klebsiella pneumoniae 03:K1 as a powerful adjuvant. Using a gel-diffusion technique, antibodies reacting with liver-specific lipoprotein and liver-specific membrane lipoprotein were detected in approximately 50% of sera from the immunized mice after an 8-mo period. After a full immunization schedule, 60%-80% of the livers of the sensitized mice developed infiltration of mono-nuclear cells consisting mainly of lymphocytes and plasma cells in portal areas, frequently associated with focal necrosis of hepatocytes. Moderate-to-severe piecemeal necrosis of hepatocytes appeared in 10 of 59 animals. However, a gradual decrease in the morphologic severity was observed 3-6 mo after cessation of injections. The transfer of splenic cells from animals with the damaged liver led to a hepatitis in recipients that was characterized by portal infiltration with mononuclear cells and by necrosis of liver parenchymal cells seen on day 14 after cell transfer. The suppressor cell activity determined by the ability of concanavalin A-activated cells to suppress blast transformation of splenic cells of normal SMA mice was significantly decreased (p less than 0.05) in mice immunized with a mixture of liver-specific lipoprotein and the polysaccaride of Klebsiella pneumoniae compared with mice immunized with the polysaccaride of Klebsiella pneumoniae alone or the polysaccaride of Klebsiella pneumoniae plus kidney lipoprotein.

Animals↗

Human erythroleukemia cell line (HEL) undergoes a drastic macrophage-like shift with TPA.

We investigated the effect of 12-O-tetradecanoyl-phorbol-13-acetate (TPA) on the human erythroleukemia cell line, HEL, and found that TPA addition (10(-6)-10(-8) M) to HEL cell cultures induces morphological, functional, and biochemical changes in HEL cells that are characteristic for macrophage-like cells. Apart from the drastic changes in morphology, the cells greatly enhance their phagocytic ability and acquire receptors for binding and degradation of chemically modified lipoproteins. At the biochemical level, a newly synthesized 85K glycoprotein is observed, and the cells are unresponsive to inducers of globin synthesis. Comparative observations with K562 cells indicate that TPA inhibits, as in HEL cells, spontaneous and induced globin synthesis, but induces minimal macrophage-like properties in these cells. The results with HEL cells are interpreted to indicate that TPA uncovers a latent monocyte-like phenotype in these cells.

Acid Phosphatase↗

Carbohydrate antigen profiles of human erythroleukemia cell lines HEL and K562.

The expression of major carbohydrate antigens carried by polylactosaminyl chains in human erythroleukemia cell lines, K562 and HEL, was investigated by applying monoclonal antibodies recognizing specific carbohydrate determinants. The two cell lines showed common differences in their glycolipid compositions: (1) the presence of significant amounts of ganglio-series glycolipids, which are absent in normal erythrocytes; and (2) a remarkable reduction in the amount of globo-series glycolipids, which are the major glycolipids in normal human erythrocytes. A variety of differences were also detected in the carbohydrate antigens carried by lacto-series glycolipids and glycoproteins having related carbohydrate chains. K562 cells were i+H-X+, with a minor population of I+ cells. HEL cells were I-i+H+X-. The presence of the I+ population in K562 cells is particularly noteworthy, since I-antigen is characteristic of adult mature erythrocytes and is absent in most human leukemic cell lines. Several clones showing I+, I+/-i+/-, or I-i+ specificities were isolated from K562 cells by cloning in either methylcellulose media or limiting dilution, and I+ and I- cells were sorted by FACS fluorometer. HEL cells and these K562 clones provide a useful experimental model for studying the biologic significance and enzymatic control in expression of cell surface polylactosamines.

ABO Blood-Group System↗

The surface antigen profile of HEL cells.

The surface antigen profile of HEL cells was probed with a panel of monoclonal antibodies that have been associated with various hemopoietic lineages. Although the list of antibodies tested is by no means complete, the following characteristic picture emerges. a. Affiliation of HEL cells with erythroid lineage has been secured by other than the globin criteria. In this respect differences with K562 cells have been mostly of a quantitative nature, with only a few exceptions. One notable exception is the presence of group H determinant in HEL cells. b. There is a strong expression in HEL cells of determinants present in the platelet/megakaryocytic series. K562 cells express only selective determinants for this lineage. c. In contrast to K562 cells, there is a strong expression in HEL cells of monocyte-associated determinants. Corroborating this are the cytochemical properties of the HEL cells [11] and their induction by TPA (12-0-tetradecanoyl-phorbol-13-acetate) to a macrophage-like phenotype [41]. d. Granulocyte-specific antigens have not been found in HEL cells, although shared antigenic determinants of granulocytes with other cells can be expressed. In contrast, K562 cells display several granulocyte-specific antigens. e. No T-cell-associated antigens are found in HEL cells, although some B-cell-associated determinants can be detected. The interpretation of the composite phenotype in HEL cells is, as yet, unclear. One fact stands out, however; the only two erythroid-associated lines available today also display a multilineage-affiliated phenotype that seems to have no parallel with the other cell lines thus far described.

Antigens, Surface↗

Further studies of the polysaccharide of Klebsiella pneumoniae possessing strong adjuvanticity. III. Augmentation of the antibody response to subcutaneously injected sheep red blood cells by the adjuvant polysaccharide.

The adjuvant action of the O3 antigen of Klebsiella (KO3) on the antibody response to sheep red blood cells (SRBC) was elucidated by injecting both KO3 and SRBC subcutaneously at the right inguinal region of SMA mice. We demonstrated that KO3 exhibits a novel ability to augment anti-SRBC plaque-forming cell responses in both the local lymph node and the spleen at a relatively late stage of immunization. Escherichia coli lipopolysaccharide, dextran sulfate and concanavalin A showed such an action only minimally. In parallel with the development of the adjuvant action, KO3 definitely activated B cells in the local lymph node polyclonally for either IgM or IgG synthesis, suggesting that the mechanism of the adjuvant action includes direct stimulation of B cells by KO3 at the late stage. Neither increase in trapping of lymphocytes in the local lymph node nor change in tissue distribution of antigen was shown to be primarily involved in the mechanism of the adjuvant action.

Adjuvants, Immunologic↗

B lymphoblast antigen (BB-1) expressed on Epstein-Barr virus-activated B cell blasts, B lymphoblastoid cell lines, and Burkitt's lymphomas.

Two new cell surface antigens expressed on B lymphoblastoid cell lines (B-LCL) were defined with cytotoxic mouse monoclonal antibodies. One marker, BB-1 (for B lymphoblast antigen-1), was detected on human and nonhuman primate B-LCL, Epstein-Barr virus (EBV)-activated B cell blasts, most Burkitt's lymphomas, and Ia+ B lymphoblast-like myelomas. Polyclonal B cell activators such as pokeweed mitogen (PWM) and lipopolysaccharide (LPS) also induced the expression of BB-1 on immunoglobulin (Ig)-positive cells. In contrast, BB-1 could not be detected on normal lymphoid tissues by complement-dependent cytotoxicity and immunofluorescence (IF) assays or by analysis with a fluorescence-activated cell sorter (FACS). T cell blasts, T cell leukemias, and pre-B cell or erythroblastic leukemia cell lines were also BB-1 negative. Of particular interest was the finding that BB-1 was expressed on the Jijoye lymphoma but only marginally on a subline of Jijoye, P3HR-1, that lacks receptors for EBV and produces a defective virus incapable of transforming lymphocytes. A second lymphoblast antigen (LB-1) unlike BB-1, was present on both T and B cell blasts and virus-transformed T- and B-LCL but not on normal lymphoid tissues.

Animals↗

Suppression of B-memory cell function by polyclonal lymphocyte activators.

When various polyclonal lymphocyte activators (PLA), such as the capsular polysaccharide of Klebsiella pneumoniae (CPS-K), E. coli lipopolysaccharide (LPS), concanavalin A (Con A), dextran sulfate (DS), phytohemagglutinin (PHA), and pokeweed mitogen (PWM) were injected into mice primed with sheep red blood cells (SRBC), anti-SRBC secondary plaque-forming cell (PFC) responses in vitro of their spleen cells to SRBC and to polyclonal B cell activatory (PBA) were more or less decreased. The decrease in the responsiveness was accompanied by the decrease in the number of SRBC-specific rosette-forming cells (RFC) of B-cell type (B memory cells). This resulted neither from emigration of RFC out of the spleen, nor from change of RFC to antibody-forming cells. Further, we revealed that the decreased responsiveness occurs exclusively in the B cell-rich fraction of the spleen cells from PLA-treated SRBC-primed mice, but not in their T cell-rich fraction. It is concluded therefore that PLA exhibited a common action to reduce selectively B-memory cell function by decreasing the number of B memory cells without differentiation to their end cells, although the strength of the action of various PLA varied.

Animals↗

Formation of mononuclear phagocyte (macrophage) colonies by mouse spleen cells in liquid culture. II. Its inhibition by the capsular polysaccharide of Klebsiella pneumoniae.

The effect of the capsular polysaccharide of Klebsiella pneumoniae type 1 Kasuya strain (CPS-K) on the formation of macrophage colonies in cultures of mouse spleen cells was investigated by the liquid culture technique during an incubation period of 7-8 days. CPS-K markedly inhibited further generation of macrophage colonies when added at any time after the beginning of culture, whereas it showed no destructive effect on macrophage colonies which were already formed before its addition. When CPS-K was present throughout the incubation period, such a low concentration as 0.05 micrograms/ml significantly inhibited colony formation, and the intensity of its inhibitory effect depended on its dose in the range of 0.005-50 micrograms/ml. The inhibitory effect persisted even if CPS-K was washed out after spleen cells were kept in contact with 20 micrograms of CPS-K per ml at 37 C for 6 hr. It was found that the inhibitory effect of CPS-K on colony formation was not mediated through its action on T cells, B cells or macrophages, and that it was not due to the generation of suppressor cells capable of inhibiting colony formation. It is concluded therefore that CPS-K directly inhibits the proliferation of macrophage colony-forming cells. The active substance responsible for the inhibitory effect of CPS-K on colony formation is the neutral polysaccharide fraction of CPS-K.

Animals↗

Adjuvant action of capsular polysaccharide of Klebsiella pneumoniae on antibody response. VIII. Its effect on the size and the number of cells of regional lymph node and other lymphoid organs.

Changes in the number of cells and the weight of various lymphoid organs of mice, such as the regional lymph node (right inguinal node), spleen, thymus, bone marrow, and peripheral blood, were followed after the subcutaneous injection of the capsular polysaccharide of Klebsiella pneumoniae (CPS-K). For comparison, the changes after injection of various polyclonal lymphocyte activators (PLA) including various preparations of bacterial lipopolysaccharide (LPS) were concurrently studied. The number of cells of all of the lymphoid organs tested and that of nucleated cells in the peripheral blood decreased significantly within a few days after injection of CPS-K, and increased later. Above all, the increase in the number of cells and in the weight of the regional lymph node was most prominent (about 10 times larger than that of the normal control). Such a marked increase in the number of cells of the regional lymph node was not induced by the injection of any preparation of LPS or any other PLA tested. The initial decrease in the number of cells after CPS-K injection was most marked and long lasting in the thymus. Although LPS prepared by Westphal's method from Escherichia coli 055 or Salmonella enteritidis exhibited a stronger decreasing effect on the number of cells of the thymus, the effect of LPS prepared by Westphal's method from E. coli O111 or that by Boivin's method from E. coli O55 was similar to that of CPS-K. It is concluded therefore that CPS-K has the ability to decrease the number of cells of various lymphoid organs, especially that of the thymus, initially after injection, which is a property in common with LPS, and CPS-K has a unique ability to increase markedly the cells of various lymphoid organs, especially those of the regional lymph node, at later stages after injection. Considering that CPS-K exhibits a much stronger adjuvant effect on the antibody response than does LPS or other polyclonal lymphocyte activators, it is suggested that this extraordinarily potent activity of CPS-K in increasing the number of cells of the regional lymph node is closely related to its strong adjuvant action.

Adjuvants, Immunologic↗

Formation of mononuclear phagocyte (macrophage) colonies by mouse spleen cells in liquid culture. I. Kinetics of appearance of colonies and characterization of macrophage colony-forming cells.

When spleen cells of the adult mouse were tested for the formation of mononuclear phagocyte (macrophage) colonies by the liquid culture technique with an incubation period of 7--8 days, about 100 macrophage colonies were produced from 1 X 10(6) cells. The number of macrophage colonies appearing after 2 days of incubation was small, but thereafter increased progressively up to at least 8 days. In the later stages of incubation (after day 6) large colonies consisting of more than 100 cells appeared. Macrophage colonies in the early stages consisted almost solely of macrophages. On day 6 significant numbers of small round mononuclear cells with no detectable phagocytic activity were seen in the center of large colonies, and by day 8 marked crowding of these cells had occurred. The peripheral region of the large colonies consisted mainly of macrophages and the intermediate region of middle-sized round or slightly stretched cells with weak phagocytic activity. Approximately two-thirds of the colony-forming cells still remained after glass-adherent cells were removed from the spleen cells by passing over a glass-bead column. In cultures of glass-nonadherent cells macrophage colonies were not generated in the early stage. The number of colony-forming cells did not change significantly even after actively phagocytic cells were rigorously removed from the spleen cells. In addition, no macrophage colonies were generated in cultures of spleen cells treated with mitomycin C.

Animals↗

Adjuvant action of capsular polysaccharide of Klebsiella pneumoniae on antibody response. IX. Its effect on the histology of the regional lymph node and other lymphoid organs.

The sequence of histological changes in the regional lymph node and other lymphoid organs of mice injected with the capsular polysaccharide of Klebsiella pneumoniae (CPS-K) or bacterial lipopolysaccharide (LPS) was followed. Injection of CPS-K, but not LPS, induced the following characteristic histological changes in the regional lymph node. In the early stage there was a marked decrease in the number of small lymphocytes, accompanied by the appearance of scattered fragmented nuclei and infiltration of polymorphonuclear neutrophilic leukocytes, and in the late stage there was marked proliferation of macrophage-like cells and pyroninophilic cells. Histological changes in the thymus and spleen and changes in cell populations in the bone marrow and peripheral blood after CPS-K injection were essentially the same as after LPS injection. Since CPS-K has a much stronger adjuvant action on antibody response than does LPS, it is suggested that the characteristic histological changes in the regional lymph node after injection of CPS-K are closely related to its extraordinarily strong adjuvant action.

Adjuvants, Immunologic↗