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K Sugiura

Publications and source records attributed to K Sugiura.

At least 19 recordsLinked to original sources

Effect of human immunodeficiency virus-1 envelope glycoprotein on in vitro hematopoiesis of umbilical cord blood.

Although hypercellularity is a common bone marrow finding in patients with human immunodeficiency virus type 1 (HIV-1) infection, the effect of HIV-1 on the hematopoietic system, which has been investigated in in vitro studies, is still controversial. In this study, we have investigated the effects of HIV-1 envelope glycoprotein, gp160, on the differentiation of hematopoietic progenitor cells derived from cord blood. Culture of cord blood mononuclear cells with gp160 resulted in enhancement of the in vitro growth of myeloid hematopoietic progenitors. To investigate the mechanism of the enhancement, adherent cells, T cells, or CD34-bearing hematopoietic progenitors were isolated and cultivated with gp160 in a variety of culture conditions. We have shown that gp160 had no direct effect on highly purified hematopoietic progenitors but exerted its enhancing effect indirectly via T cells, by induction of a humoral colony-stimulating factor(s). The activity of gp160 on T cells was abrogated by preincubation of gp160 with recombinant CD4 molecule and goat anti-gp120 antibody. These data provide evidence for a novel biological activity of HIV envelope glycoprotein, that of T-cell-mediated stimulation of myelopoiesis. Binding of gp160 with the cell surface CD4 molecule appears to be necessary for secretion of the colony-stimulating factor(s).

Antibodies

Age-dependent increase of extrathymic T cells in the liver and their appearance in the periphery of older mice.

The liver is a major site of generation of extrathymic T cells with unique properties (e.g., expressing intermediate TCR and containing self-reactive clones). We investigated herein whether the levels of extrathymic alpha beta T cells varied in various organs as a function of age. A systematic examination of the number of mononuclear cells in various organs of BALB/c mice revealed that the number of hepatic MNC increased with age whereas the number of thymocytes decreased. These changes were more striking in mice fed under conventional conditions than under specific pathogen-free condition. The age-dependent changes in the number of mononuclear cells in the spleen and lymph nodes were minimal. Although the total proportion of alpha beta T cells in each organ remained constant, the staining patterns of TCR-alpha beta as shown by immunofluorescence profiles varied. The most prominent change was that intermediate TCR-alpha beta cells, which constituted a small population in the liver of young mice, expanded in the liver of older mice. Intermediate TCR cells appeared even in the periphery of older mice. These findings were confirmed by the appearance of extrathymic T cells with other unique properties, e.g., double-negative CD4-8- phenotype and CD44 expression. In athymic nude mice, only intermediate TCR cells were present in the liver and periphery. An age-dependent increase of intermediate TCR cells was also seen in these mice. Taken together with the result of bromodeoxyuridine-injection experiment, which showed an intensive in vivo proliferation of cells in the hepatic sinusoids, extrathymic T cells may differentiate predominantly in the liver and appeared even to the periphery in older mice.

Age Factors

Estrogen administration activates extrathymic T cell differentiation in the liver.

In addition to T cell differentiation in the thymus, we have recently reported that extrathymic T cell differentiation occurs preferentially in the sinusoids of the liver. Although this extrathymic pathway is relatively minor in normal mice, it becomes predominant in mice with autoimmune diseases, athymic mice, and aged mice. In the present study, injection of normal male C3H/He mice, 6-8 wk of age, with 1 mg of estrogen resulted in an increase in mononuclear cells (MNC) yielded from the liver and a drastic decrease in thymocytes approximately 10 d after such injection. This unique modulation was not observed with hydrocortisone injection (5 mg/mouse, i.p.) nor with irradiation (5 Gy/mouse). Rather, these immunosuppressive treatments induced a simultaneous decrease in cell number in both the liver and thymus. A time-kinetics study on the cell number and spontaneous cell proliferation revealed that an increase in spontaneous cell proliferation in the liver preceded the increase in the number of liver MNC, and a decrease in spontaneous cell proliferation in the thymus preceded the decrease in the number of thymocytes. At this time, an enrichment of alpha/beta T cells with intermediate T cell receptors (TCRs), including forbidden T cell oligoclones and V beta 8+ cells, which are characterized as extrathymic alpha/beta T cells with unique properties, took place in the liver. On the other hand, the thymic atrophy induced by estrogen resulted in a prominent decrease in immature double-positive (CD(4+)8+) alpha/beta T cells with dull TCRs. These results indicate that estrogen administration activates an extrathymic pathway of T cell differentiation in the liver and reciprocally inactivates the intrathymic pathway. As extrathymic T cells have unique characteristics such as autoreactivity, the present findings might be intimately related to a female predominance of autoimmune diseases and suggest a possible role of estrogen in this phenomenon.

Animals

Activation of extrathymic T cells in the liver and reciprocal inactivation of intrathymic T cells by bacterial stimulation.

We recently demonstrated that the liver might be a major site of extrathymic T cell differentiation, including both alpha beta and gamma delta T cells. This extrathymic pathway in the liver, which has a relatively minor role in normal young mice, is activated in mice under bacterial stimulation. In the present study, we investigated how the extrathymic and intrathymic T cell differentiations were mutually related in mice injected intravenously with 10(8) heat-killed Escherichia coli. Three days after stimulation, extrathymic T cells in the liver were observed to be prominently activated in terms of increases in the total number of cells yielded, spontaneous cell proliferation in in vitro culture, and intermediate alpha beta TCR cells. Intermediate alpha beta TCR cells were extrathymic T cells uniquely seen in the liver. However, at the same time intrathymic T cells were profoundly inactivated, showing decreases in the number of thymocytes (more than 90% atrophy), spontaneous cell proliferation, and dull TCR cells with double positive CD4+8+ phenotype. With time, these responses were reversed and normal states were regained. These results suggested that extrathymic and intrathymic T cells are always activated or inactivated in the opposite direction, and that the liver and the thymus are dynamic immune organs. It raises the possibility that the extrathymic T cell differentiation in the liver and the intrathymic T cell differentiation may be reciprocally regulated by certain factors.

Animals

Functional analyses of lpr gene in MRL/Mp-lpr/lpr mice. Role of lymph node stromal cells in lpr-lymphadenopathy.

To clarify the mechanism by which the lpr gene causes lymphadenopathy, we established an experimental system to induce lymph node (LN) swelling in unaffected mice. In MRL-(+)/+ mice that had been 5 Gy-irradiated and grafted with bone marrow cells (BMCs) plus LN from MRL-lpr/lpr mice, a remarkable enlargement of the LN grafts was seen. The enlarged grafts lacked normal LN structure and were indistinguishable from LNs of MRL-lpr/lpr mice. The induction of LN swelling by this method was achieved not only in [MRL-lpr/lpr-->MRL-(+)/+] but also in [MRL-lpr/lpr-->BALB/c], [MRL-lpr/lpr-->C3H], [B6-lpr/lpr-->B10.Thy1.1], and [B6-lpr/lpr-->BALB/c] combinations. Furthermore, the lpr/lpr LN grafts developed lymph node swelling even without the transplantation of BMCs. Most cells in the grafted LNs disappeared within a few days, and large clear fibroblast-like cells then became dominant for 1 to 4 weeks. Thereafter, lymphoid cells increased and had filled the graft by the 8th week. The LN grafts obtained from MRL-lpr/lpr (but not MRL-(+)/+) mice showed the ability to transfer LN node swelling into the secondary MRL-(+)/+ hosts two weeks after the primary transplantation. These results strongly suggest that the fibroblast-like LN stromal cells play a crucial role in lpr-associated lymphadenopathy.

Animals

Significance of different levels of the Edinburgh 2 coma scale calculated from the outcome of neurosurgical patients.

In the management of patients with acute cerebral disturbances, it is essential to determine precisely the degree of impaired consciousness. In order to secure the accuracy of observations, one must use a reliable coma scale. We have evaluated the Edinburgh 2 coma scale (E2CS) and explored the relationship between levels of the E2CS and the final outcome. Case notes and observation charts of the past 7 years were reviewed, covering neurosurgical operations on 406 patients, in each of whom the postoperative course was evaluated periodically by the E2CS and the outcome was determined by the Glasgow outcome scale. By matching the outcome with each level of impaired consciousness, about 22,000 pairs of data were obtained. In order to quantify the morbidity rate, different stages of the Glasgow outcome scale were rated from 100 through 0, arbitrarily. It was proved that levels of the E2CS were arranged in the correct order in respect to both mortality and morbidity rates. It was shown at the same time that each level has different prognostic significance and that the distance between each level is not identical. The recommendation is made to separate the levels on a chart not by an ordinal number but by the distance calculated on the basis of either mortality or morbidity rates. This will make it possible to get a rough estimate of the patients' prognoses by simply looking at a daily clinical chart.

Adolescent

[A clinical and ultrastructural study of Fechtner syndrome in two Japanese families].

This is a report of Fechtner syndrome in two Japanese families. Six members of family I and three members of family II were studied. All but one had macrothrombocytopenia and leukocyte inclusion bodies, four had deafness, four had persistent proteinuria and none had cataracts. Under a diagnosis of ITP, two of them had splenectomy which resulted in no response. History revealed, other family members with deafness and/or nephritis were confirmed in both families. Ultrastructural studies of leukocytes showed oval inclusion bodies with unclear borders containing many fine ribosome like granules and randomly scattered filaments. Ultrastructural studies of macrothrombocytes were unremarkable except for a well-developed open canalicular system. More than half of megakaryocytes had uneven basophilic speckles in the cytoplasm, which were positive for Unna-Pappenheim staining. Ultrastructurally, widening of demarcating systems and remaining ribosomes were noted in the cytoplasma of mature megakaryocytes.

Deafness

Lymphotoxin activates hepatic T cells and simultaneously induces profound thymic atrophy.

We have recently demonstrated that the liver may be a major site of extrathymic T-cell differentiation. This hepatic pathway was shown to be activated in mice injected with heat-killed bacteria. It is conceivable that the resulting activation of macrophages or lymphocytes, and the production of cytokines may be responsible for a subsequent activation of hepatic T cells. In this context, we investigated the possibility of whether certain cytokines may activate hepatic T cells. It was demonstrated that the administration of lymphotoxin [tumour necrosis factor-beta (TNF-beta)] more than doubled the number of hepatic mononuclear cells (MNC) yielded 3-5 days after the treatment. More strikingly, such treatment induced profound thymic atrophy and resulted in a decrease of more than 95% in the number of thymocytes. Spontaneous proliferation in an in vitro culture of hepatic MNC from treated mice increased, and inversely such activity of thymocytes decreased. The increased number of hepatic MNC was mainly due to an increase in intermediate alpha beta T-cell receptor (TcR) cells, which are extrathymic T cells uniquely seen in the liver. On the other hand, the thymic atrophy was caused by the prompt apoptotic death of dull alpha beta TcR cells with double-positive (DP) CD4+ CD8+ phenotype. These results indicate that lymphotoxin may be one of the factors that activates extrathymic T cells in the liver and at the same time inhibits intrathymic T-cell differentiation.

Animals

Ontogeny and development of extrathymic T cells in mouse liver.

We previously demonstrated that the liver may be a major site of extrathymic T-cell differentiation in mice. In the present study, the ontogeny and subsequent development of such T cells in the liver and other organs were investigated. This study was possible because these T cells have T-cell receptors (TcR) of intermediate intensity (i.e. intermediate TcR cells) and constitutively express a high level of interleukin-2 receptor beta chain (IL-2R beta). Therefore the two-colour staining for CD3 (or alpha beta TcR) and IL-2R beta identifies even a small proportion of intermediate TcR cells. The total numbers of mononuclear cells obtained from the liver, thymus and spleen varied from foetal to adult life. Especially in the liver, many haematopoietic cells were present in the parenchymal space at the foetal stage. There were no lymphocytes in the sinusoidal lumen at this period. In contrast, lymphocytes appeared in the hepatic sinusoids after birth and increased with ageing. Phenotypic analysis revealed that intermediate TcR cells appeared in the liver and spleen on Day 4 after birth. Bright TcR cells of thymic origin were also present in the peripheral organs on Day 4. Thereafter, intermediate TcR cells increased in the liver, whereas bright TcR cells increased in the periphery as a function of age. Similarly, thymectomized and congenitally athymic mice had mainly intermediate TcR cells in the liver and, to some extent, periphery. It is concluded that intermediate TcR cells, possibly of extrathymic origin, are generated only after birth and expand with ageing.

Aging

Enrichment of murine bone marrow natural suppressor activity in the fraction of hematopoietic progenitors with interleukin 3 receptor-associated antigen.

Natural suppressor (NS) activity has been identified in several sites of active hematopoiesis. In this study we characterized NS activity in murine bone marrow (BM) using monoclonal antibodies (mAbs) to interleukin 3 (IL-3) receptor-associated antigen (IL-3RAA) and various cytokines that exert a strong influence on hematopoiesis or lymphocyte interaction. NS activity of BM cells of relatively low density was enhanced by IL-3 or granulocyte-macrophage colony-stimulating factor (GM-CSF). When the BM cells were separated into IL-3RAA+ cells and IL-3RAA- cells, the IL-3RAA+ cells demonstrated potent NS activity, whereas IL-3RAA- cells had either no or weak NS activity. The IL-3RAA+ cells showed non-T- and non-B-cell phenotype and had high affinity to wheat germ agglutinin (WGA), a marker for hematopoietic progenitors. In assays for hematopoietic activity, it appeared that the early differentiating progenitors (day 8 spleen colony-forming units [CFU-S], granulocyte-macrophage colony-forming units [CFU-GM]) were enriched in the IL-3RAA+ cell population, whereas more immature multipotent progenitors (day 12 CFU-S, granulocyte erythrocyte macrophage megakaryocyte colony-forming units [CFU-GEMM]) were contained in the IL-3RAA- cell population. Both suppressor cells and IL-3RAA+ cells spontaneously developed from the IL-3RAA- cell population. These findings suggest that NS cells in murine BM are early hematopoietic progenitors and are probably committed to the myeloid lineage. Hybridoma cells established between the IL-3RAA+ cells and BW5147 cells produced suppressor factor(s). This finding suggests that the NS cells produce soluble mediator(s) that may be responsible for their suppressive action.

Animals

Reciprocal T cell responses in the liver and thymus of mice injected with syngeneic tumor cells.

We investigated the T cell responses in various tissues, especially in the liver and thymus, of mice injected with syngeneic tumors. This study was undertaken since recent evidence indicated that the liver is one of the important immune organs for T cell proliferation. When C3H/He mice were intraperitoneally injected with mitomycin-treated syngeneic MH134 tumors (1 x 10(7)/mouse), a transient increase of liver mononuclear cells (MNC) was induced, showing a peak at Day 4 after injection. Histological study of such liver showed a sinusoidal dilatation and an accumulation of MNC in the sinusoids. The most predominant MNC induced were double negative (CD4-8-) alpha beta T cells and gamma delta T cells. These gamma delta T cells varied, showing unique time-kinetics. Despite a continuous increase of whole liver MNC and alpha beta T cells, the proportion of gamma delta T cells in the liver decreased beginning 4 days after injection. In contrast with the response in the liver, a striking decrease in the cell number of thymocytes was induced after tumor injection, showing a basal level at Day 6. This hypocellularity in the thymus appears to be an inverted response of the lymphocytosis in the liver. At this time, a corresponding decrease in the proportion of double positive (CD4+8+) T cells was always seen in the thymus. Analysis of cell proliferative response showed that the increase of liver MNC after tumor injection was accompanied by augmented proliferation, whereas the decrease of thymocytes was accompanied by depressed proliferation. The present results indicate that there exists a unique, reciprocal response of T lymphocytes between the liver and thymus, and that the presence of tumor appears to stimulate T cell response in the liver but alternatively inactivates such response in the thymus.

Animals

Unusual alpha beta-T cells expanded in autoimmune lpr mice are probably a counterpart of normal T cells in the liver.

Autoimmune MRL-lpr/lpr (lpr) mice develop severe lymphadenopathy, characterized by the accumulation of alpha beta-T cells with CD4-8- double negative (DN) phenotype, at the onset of disease. We previously demonstrated that the liver is a major site for the proliferation of such DN alpha beta-T cells. Herein, we further demonstrate that a large proportion of alpha beta-T cells in the liver and other organs, except the thymus, of lpr mice have unique properties, such as DN phenotype, relatively dull TCR intensity, a preponderance of V beta 8+ cells, and Pgp-1 expression. Interestingly, alpha beta-T cells in the liver of normal mice were found to consist of T cells with intermediate intensity of TCR (i.e., brighter than thymic dull TCR and lower than thymic bright TCR) as well as with bright intensity of TCR in the immunofluorescence test. These hepatic alpha beta-T cells with intermediate TCR in normal mice were found to have properties similar to those of alpha beta-T cells in lpr mice. These results suggest that abnormal alpha beta-T cells in lpr mice are a counterpart of normal T cells in the liver. An abnormal expansion of such T cells in the liver might be fundamental to the pathogenesis involved in these autoimmune mice.

Animals

An appropriate in vitro culture condition for the induction of human TCR gamma delta + cells by heat-killed bacteria.

TCR gamma delta + cells proliferated when MNC were stimulated with various heat-killed bacteria. We investigated here the culture conditions for their maximum proliferation. MNC were cultured for 6 days with Streptococcus pyogenes, and for 3 days with T cell mitogens, PHA and anti-CD3 mAb, in medium supplemented with various concentrations (0.05-50%) of human sera. TCR gamma delta + and TCR gamma delta- CD2+3- double negative cells induced by Str. pyogenes required high concentrations of sera (greater than 6%) for their proliferation. Moreover, increased sera (up to 50%) greatly augmented their proliferation. On the other hand, TCR alpha beta + cell proliferation induced by T cell mitogens was supported by a small concentration (even 0.1%) of the sera, and the addition of high concentrations of sera (greater than 6%) somewhat suppressed responses. Similar serum requirement patterns were evident for the induction of cytotoxic cells. These results clearly demonstrated the existence of an appropriate culture condition for the proliferation of TCR gamma delta + cells induced in vitro.

Adult

Transplantation of wheat germ agglutinin-positive hematopoietic cells to prevent or induce systemic autoimmune disease.

Hematopoietic stem cell defects are thought to be involved in the etiopathogenesis of systemic autoimmune disease. Positively selected, stem cell-enriched populations of wheat germ agglutinin-positive (WGA+) low-density bone marrow and fetal liver cells from normal and autoimmune-prone mice were used to determine whether reciprocal transplantation of stem cells between normal and autoimmune-prone mice inhibits or causes development of autoimmune disease. NZB recipients of DBA/2 stem cell populations analyzed greater than 100 days after bone marrow or fetal liver cell transplantation showed decreased levels of anti-DNA antibodies and decreased glomerular lesions when compared with nontreated NZB mice or NZB recipients of NZB stem cell preparations. Female DBA/2 recipients of WGA+ NZB bone marrow cell or fetal liver cell transplants exhibited elevated serum autoantibody levels and developed glomerular lesions characteristic of NZB mice when analyzed greater than 100 days after transplantation. These pathological disturbances were not observed in DBA/2 recipients of DBA/2 stem cell preparations. The data indicate that WGA+ stem cells from autoimmune-prone NZB mice contain the genetic defects responsible for the development of systemic autoimmune disease.

Animals

[Spontaneous disappearance of a middle fossa arachnoid cyst--a case report].

A case of a middle fossa arachnoid cyst which spontaneously disappeared is reported. A 16 year old boy visited our out-patient clinic complaining of headache after a blunt head trauma by a motorcycle accident. The neurological examination was negative except for mild neck pain on the flexion and extension of neck. Plain x-ray of skull and neck were negative. CT scan demonstrated an arachnoid cyst in the left Sylvian fissure. It was planned to follow up the patient by CT scan. After 10 months, he was examined by CT scan, which revealed the spontaneous disappearance of the arachnoid cyst and some dilatation of the anterior horn of the lateral ventricle. The patient did not have any additional trauma or infection during the interval between two examinations. Spontaneous disappearance of arachnoid cyst was extremely rare as only 4 cases were reported previously. The basic mechanism of this natural cure was considered to be rupture of outer or inner membrane of arachnoid cyst which would facilitate absorption of its content.

Adolescent

[Deformation of brain and stress distribution caused by putaminal hemorrhage--numerical computer simulation by finite element method].

Deformation and stress distribution caused by putaminal hemorrhage in two-dimensional model brain were analyzed by computer simulation using finite element method. The model brain was composed of cerebral cortex, white matter, caudate nucleus, lenticular nucleus, thalamus and lateral ventricle. Young's modulus of gray and white matter was assumed to be 0.08 and 0.04 kgf/cm2, respectively, and Poisson's ratio was 0.47 for both of them. Bleeding of 100 mmHg pressure was represented by 4 vectors of force directing anterior, lateral, posterior and medial direction from the middle portion of putamen. Calculation of finite element method was carried out by a 16-bit personal computer. The calculated deformation of brain presented a hematoma cavity elongated from anterior to posterior direction at the lenticular nucleus. Mass effect of hematoma was noted from displacement of the anterior horn of the lateral ventricle and the internal capsule. Distribution of stress vector revealed the stress concentration at the lenticular nucleus while small stress was noted all over the model brain. Strength of principal stress was presented by contour-line and took the shape of concentric circles with a center at the putamen. This study suggested that the computer simulation by finite element method would be a useful technique to analyze the physical phenomenon of brain suffered from intracerebral hemorrhage.

Basal Ganglia Diseases

Long-term immunologic tolerance induction in chimeric mice after bone marrow transplantation across major histocompatibility barriers: persistent or redeveloping immunologic responsiveness after prolonged survival.

Employing allogeneic bone marrow chimeras [B6----C3H] (C3H/HeN mice lethally irradiated and then reconstituted with T cell-depleted C57BL/6J bone marrow), we investigated the kinetics of immunological reconstitution and the functional characteristics of the immune system at regular intervals following bone marrow transplantation (BMT). In chimeric mice, almost all spleen cells and peritoneal macrophages showed donor H-2 haplotype within 2 weeks after BMT. The differentiation and maturation of B lymphocytes and macrophages was largely complete by 2 weeks following BMT, whereas T cell functions such as Con A responsiveness and alloreactivity were not restored within 4 weeks. Newly developed T cells were found to be exclusively of donor origin but were tolerant of both donor type and host type major histocompatibility complex (MHC) determinants in assays of mixed lymphocyte reactions and capacity to generate cytotoxic T lymphocytes. Fully allogeneic chimeric mice survived up to one year after bone marrow transplantation without significant reactions or serious diseases. Neither graft-versus-host reaction (GVHR), host-versus-graft reaction (HVGR), nor the wasting diseases described. As compared to age-matched control mice, such fully allogeneic chimeras exhibited one year following BMT somewhat reduced but quite significant plaque forming cell responses to in vitro stimulation with a T-dependent antigen, SRBC. These findings suggest that BMT across MHC barriers may ultimately be useful in humans if all manifestations of GVHR are eliminated by completely removing all T cells from the bone marrow and if all hematopoietic resistance and all aspects of HVGR are eliminated by using sufficient immunosuppression and myeloablation.

Animals

[Estimation of prognosis in patients with putaminal hematoma].

In order to determine the factors affecting the functional prognosis of operated putaminal hematoma patients, the relationship between the final outcome and the acute stage clinical factors were analyzed by the use of multimodality analysis method (Hayashi's Qualification Type 2). Forty-five consecutive cases who admitted to and operated on during the last two years were included in this study (30 male and 15 female patients, the distribution of age was 40 to 75 years old). Clinical factors just prior to surgery were collected from the case record and categorized to calculate the Pearson's product moment correlation coefficient against the Glasgow Outcome Scale. Five clinical factors with the correlation coefficient above 0.5 (Edinbugh 2 coma scale (0.85), light reflex (0.67), respiratory status (0.61), age (0.58) and the side of the lesion (0.50) were used to apply the Hayashi's Qualification Type 2 analysis. By this method, each categories are given scores so that the different outcome separate maximally. The correct estimation ratio for outcome was 100% for good recovery, 30% for moderately disabled, 50% for severely disabled and 88% for death, over all correct estimation ratio being 69%. The mean scores for each outcome were 1 +/- 0.01 for good recovery (9 cases), 0.74 +/- 0.32 for moderately disabled (10 cases), 0.6 +/- 0.36 for severely disabled (10 cases) and -0.16 +/- 0.37 for dead (16 cases). There were statistical significance (p less than 0.01) between each outcome except for moderately disabled and severely disabled.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance