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A Mabuchi

Publications and source records attributed to A Mabuchi.

32 records · Page 2Linked to original sources
PubMed1990

[Liver regeneration and immune system--morphological and cytochemical studies of activated spleen cells during the liver regeneration after partial hepatectomy].

Morphological and cytochemical changes were investigated in spleen cells after 70% hepatectomy in mice. During liver regeneration after the hepatectomy, the spleen weight gradually rose to a peak at 6 day. In the spleen, the number of POD-positive myelocytic cells and NCAE-positive granulocytic cells also reached a peak 4 days after the operation and then decreased. On the other hand, ANBE-positive monocytic cells gradually increased up to 9 day and didn't decrease for this period. On day 9 of the culture, the boundary between the red and the white pulps of the spleen became unclear. In this spleen, the clusters of blast cells were sporadically observed. Splenic T cells cocultured with nonparenchymal adherent normal liver cell or nonparenchymal adherent normal liver cell supernatant developed into granulocyte colonies in earlier periods and monocyte colonies in later periods. These findings suggest that the factors released from liver cells may regulate strictly spleen cell activation. Blast cell formation in the culture with nonparenchymal adherent normal liver cell supernatant was amplified by anti interferon (alpha + beta) antibody. These facts indicate that the functional network of cytokines is formed by the interaction of various cytokines (IL-1, IL-6, CSF, IFN, etc.) in nonparenchymal adherent normal liver cell supernatant.

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PubMed1987

Antigen-specific T cell cluster formation on antigen-pulsed macrophage monolayers in mice.

We describe the quantitative measurement of antigen-specific clusters formed by antigen-pulsed macrophages and immunized T cells in mice. We have found the peripheral blood T cells show very little non-specific adhesion to macrophages in mice. By using this population of lymphocytes in the peripheral blood as the source of immunized T cells, we could quantitate antigen-specific cluster formation. On OVA-pulsed monolayers of peritoneal exudate macrophages from normal BALB/c mice, syngeneic peripheral blood T cells from donors immunized with the same antigen develop 20-40 clusters per 1,000 macrophages, whereas the same T cells on non-pulsed monolayers develop only 0-5 cluster-like accumulations of cells. On antigen-pulsed monolayers of macrophages from allogeneic (C57BL/6 or A/J) mice, clusters are developed only in the negative range (0-5/1,000 macrophages). Considering the observation by Braendstrup et al, these data seem to suggest that histocompatibility between macrophages and T cells is required to develop antigen-specific T cell clusters on antigen-pulsed macrophage monolayers, and that the genetic restriction of immune responsiveness may be directly expressed in this initial form of cellular interaction between antigen-bearing macrophages and specific T cells.

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PubMed1985

Regulation of immune response by preadministration of cells briefly pulsed with antigen in vitro. III. Functional change of antigen presenting cells.

An intravenous administration of syngeneic spleen cells (SPCs) caused the reduction of antigen presenting activity of splenic adherent cells (SACs). The antigen presenting activity of SACs was reduced 10 days after the intravenous injection of 5 X 10(7) antigen pulsed or antigen nonpulsed SPCs. In contrast, when mice were immunized 5 days after the intravenous injection of SPCs, antigen presenting activity was reduced in the mice injected with antigen pulsed SPCs, and not in the mice injected with antigen nonpulsed SPCs. This reduction was recovered by the administration of cyclophosphamide 3 days before the injection of antigen pulsed SPCs, suggesting that suppressor T cells played an important role in the reduction of antigen presenting activity.

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PubMed1984

Suppression of IgE antibody response by preadministration of antigen-pulsed spleen cells. II. Characteristics of immediate tolerance induction.

Intravenous administration of syngeneic spleen cells (SPC), briefly pulsed with antigen in vitro, resulted in a profound state of IgE antibody unresponsiveness. One of the mechanisms of this unresponsiveness is responsible for an immediate tolerance which is induced without any suppressor cells. Characteristics of this immediate tolerance were investigated. Administration of antigen-pulsed spleen cells 4 h before the immunization, suppressed the production of IgE antibody triggered by the subsequent immunization. Pretreatment with cyclophosphamide had no effect on this rapid suppression, and this suppressive state could not be transferred to normal syngeneic recipients by the injection of spleen cells from the tolerant mice used in our experiment. These observations suggest that suppressor cells do not play an important role in immediate tolerance. The extent of this immediate tolerance induced by the injection of antigen-pulsed SPC depends on the number of antigen-pulsed SPC and the dose of antigen to which SPC had been exposed. Injection route of antigen-pulsed SPC has a great influence on the induction of immediate tolerance. The order of suppressive extent is intravenous, greater than intraperitoneal greater than subcutaneous. This suppression is specific to the antigen pulsed to SPC. Carrier-specific T cells are the major target of suppression in immediate tolerance. Antigen-pulsed T cells induce immediate tolerance most effectively in the subpopulations of SPC.

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PubMed1982

Regulation of immune response by preadministration of cells briefly pulsed with antigen in vitro. I. Suppression of IgE antibody response by antigen pulsed spleen cells.

The intravenous administration of syngeneic spleen cells (SPCs) briefly pulsed with antigen in vitro, results in a profound state of IgE antibody unresponsiveness. In Balb/c mice, the primary response of anti-DNP, anti-beef insulin and anti-ovalbumin IgE antibody is completely suppressed by the administration of antigen-pulsed spleen cells, 1 X 10(7), 5 X 10(7) and 1 X 10(8), respectively. This suppression is antigen specific and effects both primary and secondary immune responses. Furthermore, the immune response to dinitrophenylated Keyhole limpet hemocyanin (DNP-KLH) is most extensively suppressed by DNP-KLH pulsed SPCs, intermediately suppressed by KLH-pulsed SPCs and minimally suppressed by dinitrophenylated mouse gamma globulin or dinitrophenylated mouse serum albumin pulsed SPCs. Suppressing directly cells specific for hapten and carrier, hapten carrier protein pulsed SPCs would caused the additive suppressive effect. The suppression is induced strongly by the intravenous administration of antigen pulsed spleen cells, slightly by the subcutaneous administration and is not induced by the intravenous administration of antigen solution in phosphate buffer saline. This suppression may be mediated by either of two different mechanisms: one of them is responsible for the immediate tolerance which is induced without any suppressor cells 1 day after the administration of antigen pulsed SPCs, and the other is responsible for the suppression transferred by suppressor cells or factors to normal mice 7 days after the administration of antigen pulsed SPCs. This method in which IgE antibody response is suppressed by the administration of cells briefly pulsed in vitro with antigen, provides a powerful tool to analyze the first step of antigen specific suppression developed in vivo by conventional antigens.

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PubMed1979

Partial purification, physicochemical characterization and biological function of a rosette-decreasing factor (RDF) extracted from guinea pig thymus.

A factor that decreases rosette formation between guinea pig T-cells and rabbit red blood cells (RRBC) was extracted from the thymus of the guinea pig. The active factor could be extracted from the spleen as well as the thymus, but not from the liver or kidney. The active factor of the thymic extract was found in the precipitates produced by 80% saturated ammonium sulfate and it was separated from the water-soluble fraction of the precipitates. The molecular weight of the partially purified substance was estimated to range between 10,000 and 30,000 by filtration through a diaflow membrane. From the studies on physicochemical characterization, it might be a heat-resistant basic peptide probably bound to a ribonucleotide moiety. This factor reduced rosette formation between RRBC and guinea pig T-cells, but did not reduce erythrocyte-antibody-complement rosette formation. This factor also inhibited mitogen (concanavalin A, phytohemagglutinin-P)- induced DNA synthesis of guinea pig lymphocytes and antigen-induced DNA synthesis of sensitized guinea pig lymphocytes.

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PubMed1978

Separation of RRBC-RFC and non-rosette forming cells (non-RFC) of guinea pig T-cell populations and their functional difference. 1. Response of RRBC-RFC and non-RFC to either Con-A or LPS.

Guinea pig lymph node cells suspension (LNC-O) was filtered through a glass wool column and the effluent (LNC-G) was further filtered through a nylon column. In this effluent (LNC-NE) about 30 per cent of the lymphocytes was identified as non-rosette forming cells (non-RFC). The non-RFC fraction was separated from LNC-NE fraction by Ficol-Conray specific gravity centrifugation or effluent cells reacted previously to rabbit red blood cells (RRBC). The upper layer after centrifugation, designated non-RFC fraction, was separated. In this fraction 96% of the cells were lymphocytes and about 95% of them were non-RFC, which lacked receptors for rabbit red blood cells (RRBC) or EAC and detectable surface immunoglobulin by conventional techniques. Though the response of the lymphocytes in the non-RFC fraction to mitogenic (Con-A, LPS) or antigenic stimulation was lower in comparison with that in RFC-rich fraction, the response of non-RFC to ConA exceeded the response to LPS. These facts suggest that at least a portion of the non-RFC may be cells from the T-cell line.

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PubMedDate not supplied

The liver as a potential hematolymphoid organ examined from modifications occurring in the systemic and intrahepatic hematolymphoid system during liver regeneration after partial hepatectomy.

In order to investigate whether or not the adult murine liver can function as one of the hematolymphoid organs, we studied the alteration of cellular characteristics in the systemic and intrahepatic hematolymphoid systems during liver regeneration after partial hepatectomy. Liver regeneration affects the systemic hematolymphoid system, as can been seen from the transient increase in colony forming unit in culture (CFU-C) frequency observed in the bone marrow at 20 hr and its gradual increase in the spleen up to the 6th day after partial hepatectomy. CFU-C were found not only in peripheral blood lymphocyte-rich fraction (PBL), but also in intrahepatic lymphocyte-rich fraction (IHL) of the normal adult liver. CFU-C frequency showed a weak increase in PBL and a dramatic increase, up to the 6th post-hepatectomy day, in IHL subfraction cells, forming a very strong liver association. Colonies, which were generated from IHL in a fibrin clot culture system, were mainly composed of granulocytes, macrophages and mast cells. Wheat germ agglutinin (WGA) positive cells too were detected in IHL and found to increase after partial hepatectomy. IHL of the normal liver were proliferated not only by IL-3 and GM-CSF but also by IL-2. The proliferative responses of IHL to these cytokines were further augmented on day 6 after partial hepatectomy. Similar results were obtained in peripheral blood and splenic lymphocyte-rich fractions. These observations, therefore, suggest that the adult murine liver has hematolymphoid cells as its component and has the function of a hematolymphoid organ closely associated with the systemic hematolymphoid system.

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PubMedDate not supplied

Production of granulocyte-macrophage colony-stimulating factor by adult murine parenchymal liver cells (hepatocytes).

In order to investigate the hematolymphoid system in the adult murine liver, we examined colony-stimulating factor (CSF) released from primary cultured liver cell fractions, parenchymal and nonparenchymal liver cells (more than 99% pure. Using a fibrin clot culture system, we found colony-stimulating activity not only in the culture supernatant from nonparenchymal fraction of normal liver cells (NP-NLC sup), but also in the culture supernatant from parenchymal fraction of normal liver cells (P-NLC sup). Clusters and colonies, which were generated in 4-day cultures of bone marrow cells or spleen cells with P-NLC sup or NP-NLC sup, were mainly composed of granulocytes (G), macrophages (M), and granulocytes and macrophages (GM). Both P-NLC sup and NP-NLC sup proliferated IC2, which is a GM-CSF and IL-3 dependent cell line, and this proliferation was completely inhibited by rabbit anti-murine GM-CSF antibody. Furthermore, both Northern blot analysis and in situ hybridization with specific cDNA probe for murine GM-CSF showed that parenchymal liver cells expressed GM-CSF mRNA transcripts. The present findings indicate that cultured murine parenchymal liver cells produce GM-CSF. The possibility, therefore, is suggested that parenchymal liver cells also play an important role in the regional hematolymphoid system of the liver.

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PubMedDate not supplied

Modification of T-lymphocyte subsets in peripheral blood, the liver, and the spleen during liver regeneration after partial hepatectomy of mice.

Flow cytometry analysis was performed to investigate the modifications to the T lymphocytes in peripheral blood, the spleen, and two intrahepatic lymphocyte fractions--the intrahepatic lymphocyte fraction 1 (IHL Fr.1), which is easily washed out from the liver by perfusion of collagenase solution, and the intrahepatic lymphocyte fraction 2 (IHL Fr.2), which remains in the liver after the perfusion--occurring in the liver regeneration process after partial hepatectomy of mice. The following findings were obtained: 1) The nontreated murine liver contains Thy 1.2+ cells, alpha beta TCR+ cells, gamma delta TCR+ cells, CD4+ cells, and CD8+ cells. 2) The percentage of each T-cell subset in IHL Fr.1 shows an intermediate value between that in the peripheral blood lymphocytes (PBL) and that in the IHL Fr.2. 3) One day after partial hepatectomy, the Thy 1.2+ cells, alpha beta TCR+ whole cells, and CD4+ cells in IHL Fr.2 all showed a transient, yet significant, decrease, but did not reveal any major change in the other fractions. 4) Both the alpha beta TCR dull+ cells and the CD8+ cells showed practically no change after partial hepatectomy in any of the fractions. This indicates that the alpha beta TCR dull+ cell/alpha beta TCR+ whole cell and the CD8+ cell/CD4+ cell ratios show a significant increase 1 day after partial hepatectomy only in the IHL Fr.2. Double-positive cells, which were scarcely found in the spleen of nontreated mice, appeared in the spleen after partial hepatectomy.(ABSTRACT TRUNCATED AT 250 WORDS)

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