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S Hanazawa

Publications and source records attributed to S Hanazawa.

At least 73 records · Page 4Linked to original sources
PubMed1990

[Inducing effect of tumor necrosis factor-alpha on differentiation of U937 monocytic tumor cell line].

We used the human monocyte/macrophage-like tumor cell line U937 to examine whether tumor necrosis factor-alpha (TNF-alpha) induces differentiation of monocyte/macrophage progenitors. Incubation of these cells with recombinant human tumor necrosis factor-alpha (rhTNF-alpha) resulted in an increase in Fc rosette formation by the cells. RhTNF-alpha increased the rosette formation in dose- and culture time-dependent manners. And the highest Fc rosette formation was observed in culture medium supplemented with 10% serum. However, U937 cell growth was not inhibited by rhTNF-alpha. The stimulatory effect of rhTNF-alpha was completely inhibited when the factor and indomethacin (10(-6) M) were added simultaneously to the cells. Also, rhTNF-alpha increased NBT reducing activity of the cells. Additionally, rhTNF-alpha-treated U937 cells produced interleukin-1 in the cell density- and culture time-dependent fashions. These results demonstrate that rhTNF-alpha is a potent inducer of the differentiation of the monocyte/macrophage-like tumor cell line U937.

Cell Differentiation↗
PubMed1990

[Mouse interleukin-1 production by Actinobacillus actinomycetemcomitans Y4 lipopolysaccharide and augmenting effect of indomethacin on its production].

The present study demonstrates the ability of Actinobacillus actinomycetemcomitans lipopolysaccharide (LPS) to elicite interleukin-1 (IL-1) production and then augmenting effect of indomethacin on this production. LPS was isolated from A. actinomycetemcomitans Y4 by the hot phenol-water procedure (A-LPS). A marked IL-1 production by peritoneal macrophages treated with A-LPS was observed in the cells from C3H/HeN mice, but not in those from C3H/HeJ mice. LPSs from A. actinomycetemcomitans ATCC 29522 and 29523 exhibited the same inducing activity for IL-1 production as did A-LPS. The IL-1 production with A-LPS was inhibited drastically when the LPS was pretreated with polymyxin B. A-LPS-induced IL-1 production was augmented significantly by treatment of the cells with a inhibitor, indomethacin, but not with a lipooxygenase inhibitor, nordihydroguariatic acid. The augmenting effect occurred as early as 3 hr after treatment of indomethacin. In light of recent studies showing that IL-1 plays a regulatory role in bone remodeling systems, the present result suggest the possibility that A-LPS-induced IL-1 may play a significant role in mechanism(s) of alveolar bone resorption in juvenile periodontitis and also that its production may be regulated by prostaglandins.

Aggregatibacter actinomycetemcomitans↗
PubMed1989

An Epstein-Barr virus-transformed B cell line produces autoregulatory interleukin-1 that regulates bone remodeling.

In this study, we demonstrate that an Epstein-Barr virus-transformed B cell line, A-11, produced interleukin-1 (IL-1), a cytokine that regulates bone remodeling. A-11 cells produce IL-1 in a cell dose- and culture time-related manner. The IL-1 activity was neutralized by recombinant human IL-1 (rhIL-1) alpha antiserum, but not by rhIL-1 beta antiserum. The IL-1 was semi-purified by (NH4)2SO4 precipitation, Superose prep 12 gel filtration, and anion-exchange chromatography strongly stimulated in vitro bone resorption. The stimulatory effect of the purified IL-1 on bone resorption was prostaglandin independent. Purified IL-1 inhibited DNA and collagen synthesis in the osteoblastic cell line MC3T3-E1. However, it enhanced significantly the cellular activity of alkaline phosphatase (EC 3.1.3.1), a marker enzyme for differentiation of osteoblasts. On the other hand, A-11 cell proliferation was inhibited by addition of rhIL-1 alpha antiserum, but not by rhIL-1 beta antiserum. And cell proliferation was stimulated by exogenous rhIL-1 alpha and -beta.

Alkaline Phosphatase↗
PubMed1989

[The use of fibrin glue for the repair of experimental nasal CSF leak in rats].

Surgical repair of cerebrospinal fluid (CSF) leak requires the production of a seal competent to resist CSF pressure during the period of healing. Direct suturing, packing with muscle and fat grafts, and coverage with mucosal or muscle flaps have been effective in repairing most CSF leaks. Fibrin glue will improve the results of a CSF leak repair by providing better adhesion of the graft and improving the initial seal during healing. Experiments were performed on 39 rats to assess the effectiveness of fibrin glue in repairing experimentally produced CSF leaks. CSF leak was produced by creating defects at the cribriform plate. There were four experimental groups; 1. no treatment control; 2. fibrin adhesive alone; 3. muscle packing alone; 4. fibrin glue with muscle packing. The CSF leaks were evaluated 3 weeks after repairs. Persistent CSF leakage was noted in 89% of group 1, 55% of group 2, 33% of group 3, and 22% of group 4. The result in the muscle plus fibrin glue group suggests that fibrin glue, by its adhesive sealing properties, improves the results of muscle packing alone for the treatment of nasal CSF leak.

Animals↗
PubMed1989

[Biological characterization of Bacteroides intermedius specific monoclonal antibody].

One monoclonal antibody (BIF6) directed against Bacteroides intermedius Group I was developed by hybridoma technology. In the present study, we used culture medium from BIF6 antibody-producing cells to characterize the antibody. Its reactivity against B. intermedius (Group I, II), B. gingivalis, B. corporis, B. melaninogenicus, B. loescheii, and B. asaccharolyticus was detected by the enzyme-linked immunosorbent assay. BIF6 monoclonal antibody specifically reacted with B. intermedius Group I, but not with B. intermedius Group II. Also, the BIF6 did not react with other black-pigmented Bacteroides. Since BIF6 antibody reacted with some clinical isolates from subgingival plaques of adult periodontal patients, we suggest that this antibody may be useful as a tool in the clinic to identify B. intermedius Group I. Specific antigen of B. intermedius Group I recognized by BIF6 antibody was located on the outer membrane of the organism. And the specific antigen was inactivated by treatment for 20 min at 80 degrees C and at pH2 and 12. Also the antigen was sensitive to trypsin treatment.

Antibodies, Bacterial↗
PubMed1989

[Production of IL-1 like cytokine by cultured bone cells: inducing effect of Haemophilus actinomycetemcomitans lipopolysaccharide on the cytokine production].

We have studies the role that interleukin-1 (IL-1) and IL-1-like cytokine play in the mechanism of bone resorption that occurs in periodontal disease. To determine whether the bone cell itself produces IL-1-like cytokine, we examined bone cells migrating from fragments of newborn mouse calvaria. These bone cells were cultured in alpha-MEM with of without fetal calf serum. IL-1-like cytokine activity was measured by incorporation of [3H] thymidine into C3H/HeJ thymocytes treated with lipopolysaccharide (LPS) from Haemophilus actinomycetemcomitans, a bacterium found in juvenile periodontopathy. The bone cells produced a significant amount of IL-1-like cytokine. The maximum production of IL-1-like cytokine was observed at 24 hours with the LPS in serum-free alpha-MEM. IL-1-like cytokine production stimulated by LPS was marked in the bone cells from LPS high-responder C3H/HeN mice, but not in those from low-responder C3H/HeJ mice. Peak of IL-1-like cytokine activity in culture supernatants of the bone cells was detected in fractions with a molecular weight corresponding to 15,000 daltons.

Animals↗
PubMed1989

Recombinant interferon-gamma is a potent inhibitor of osteoblastic cell functions.

Interleukin-1 and tumor necrosis factor-stimulated bone resorption is mediated by osteoclast-activating factor elaborated by osteoblasts. Recombinant interferon-gamma inhibits stimulation of bone resorption by these cytokines. We examined here the effects of recombinant mouse interferon-gamma (rmIFN-G) on DNA and collagen synthesis, and on alkaline phosphatase (ALP) activity, in the osteoblastic cell line (MC3T3-E1) under confluent culture conditions. Addition of rmIFN-G to the cells markedly inhibited their DNA synthesis and ALP activity in dose- and culture time-related manner. Also we found that rmIFN-G decreased markedly collagen synthesis at day 3 after addition of the agent. These data indicate that rmIFN-G is a potent inhibitor of osteoblastic cell functions.

Alkaline Phosphatase↗
PubMed1989

[Inhibitory effect of recombinant human interferon gamma on human osteoblastic osteosarcoma cells (SaOS2)].

Recent studies have suggested that interleukin-1 or tumor necrosis factor-stimulated bone resorption is mediated by osteoclast-activating factor elaborated by osteoblastic cells. Since recombinant interferon gamma inhibits stimulation of bone resorption by these cytokines, we examined here the effects of recombinant human interferon gamma (rhIFN-G) on DNA synthesis and alkaline phosphatase (ALP) activity of a human osteoblastic osteosarcoma cell line, SaOS2, under preconfluent culture conditions. Addition of rhIFN-G to the cells markedly inhibited their DNA synthesis and ALP activity in a dose-dependent fashion. However, the inhibition was not dependent on the culture time. The highest inhibitory effect was observed in 10% serum-containing culture medium. The inhibitory effect on DNA synthesis was not eliminated by addition of indomethacin, a cyclooxygenase inhibitor. Furthermore, combination of rhIFN-G and recombinant human tumor necrosis factor alpha inhibited their DNA synthesis and the ALP activity in synergistic fashion. Therefore, these data suggest that rhIFN-G is a potent inhibitor for human osteoblastic cells.

Alkaline Phosphatase↗
PubMed1988

Effects of recombinant human interleukin 1 alpha and interleukin 1 beta on cell growth and alkaline phosphatase of the mouse osteoblastic cell line MC3T3-E1.

Recombinant human interleukin 1 (rhIL-1)alpha and rhIL-1 beta were examined for their effects on DNA synthesis, cell growth and alkaline phosphatase activity of the mouse osteoblastic cell line MC3T3-E1. The relative activity of rhIL-1 alpha and rhIL-1 beta was compared in terms of the units which induced half-maximal [3H]thymidine uptake into mouse thymocyte cultures exposed to IL-1. Both rhIL-1 alpha and rhIL-1 beta significantly inhibited DNA synthesis and division of the cells in a concentration- and cultivation time-dependent fashion. In contrast, rhIL-1 alpha and rhIL-1 beta markedly increased alkaline phosphatase activity, which is a marker of osteoblastic differentiation. This activity in cells treated with rhIL-1 alpha and rhIL-1 beta increased about 2.0- and 1.7-fold, respectively, compared with that of control cultures. Inhibition of the DNA synthesis and stimulation of alkaline phosphatase activity by both types of rhIL-1 were completely neutralized by treatment with their respective polyclonal antisera. Also, inhibition of DNA synthesis was unaffected by the addition of cyclooxygenase and lipoxygenase inhibitors, and stimulation of alkaline phosphatase activity was unaffected by the addition of indomethacin. These results indicate that both rhIL-1 alpha and rhIL-1 beta have qualitatively similar biological effects on osteoblastic cells. They also suggest that IL-1 is an important modulator of the growth and differentiation of osteoblasts.

Alkaline Phosphatase↗
PubMed1988

Inductive effect of recombinant human interleukin-1 alpha and beta on differentiation of macrophage-like tumor cell line P388D1.

We used the mouse monocyte/macrophage-like tumor cell line P388D1 to test whether or not interleukin-1 (IL-1) stimulates differentiation of monocyte/macrophage progenitors. Incubation of these cells with recombinant human interleukin-1 (rhIL-1) alpha and beta resulted in their increased adherence, stimulation of nonspecific esterase activity, and increased Fc rosette formation. rhIL-1s inhibited cell growth and stimulated Fc rosette formation in a dose-dependent fashion. The cell growth inhibition due to rhIL-1s depended on the concentration of serum in culture medium. Synergism between rhIL-1 and calcium ionophore A23187 was found for the cell growth inhibition and Fc rosette formation. The presence of ethylene glycol bis- (beta-aminoethyl ether) N,N,N,N,-tetraacetic acid(EGTA) in the medium abolished the stimulatory effect of rhIL-1 on Fc rosette formation of the cell line. These results demonstrate that rhIL-1s are a potent inducer of the differentiation of the macrophage-like tumor cell line P388D1.

Animals↗
PubMed1988

Stimulatory effect on bone resorption of interleukin-1-like cytokine produced by an osteoblast-rich population of mouse calvarial cells.

We reported previously that an osteoblast-rich population of mouse calvarial cells treated with lipopolysaccharide produced on interleukin-1 (IL-1)-like cytokine that closely resembles IL-1. In the present study, we examined whether or not the IL-1-like cytokine stimulates bone resorption. As a result we found that the cytokine stimulate bone resorption significantly, and the stimulatory effect was dependent on cytokine dose and length of culture time. The stimulation of bone resorption and IL-1-like cytokine activity appear to be in parallel. Since the stimulatory effect of the cytokine was not abolished in the presence of indomethacin, the cytokine may stimulate bone resorption in a prostaglandin metabolite-independent manner. These results suggest the possibility that the IL-1-like cytokine may be involved as an autoregulatory factor in the bone-remodeling system.

Animals↗
PubMed1988

Neurogenic neoplasms in the head and neck region.

Thirteen cases of neurogenic tumor in the head and neck region experienced during the past fifteen years were reported. Six of them were neurilemmomas, three neurofibromas associated with von Recklinghausen's disease, two ganglioneuromas and two paragangliomas (chemodectomas). Representative cases were reported in detail in conjunction with considerations regarding diagnosis, treatment, and histopathologic findings by reviewing pertinent papers.

Adult↗
PubMed1988

Bacteroides gingivalis fimbriae stimulate production of thymocyte-activating factor by human gingival fibroblasts.

In a previous report (Y. Ohmori, S. Hanazawa, S. Amano, T. Miyoshi, K. Hirose, and S. Kitano, infect. Immun. 55:947-954, 1987), we showed that human gingival fibroblasts spontaneously produce thymocyte-activating factor (FTAF), which stimulates mitogen-induced thymocyte proliferation. In the present study, we examined the effect of Bacteroides gingivalis fimbriae on FTAF production by the cells, because the fimbriae may be involved in attachment of the organism to periodontal tissues. We show here that the fimbriae bind to the cells, which may subsequently lead to the stimulation of FTAF production by the cells.

Animals↗
PubMed1987

Biological characterization of interleukin-1-like cytokine produced by cultured bone cells from newborn mouse calvaria.

We have investigated the role of interleukin-1 (IL-1) and IL-1-like factor in the regulatory mechanisms of a bone remodeling system. To determine whether the bone cell itself produces IL-1-like cytokine, we examined bone cells cultured from newborn mouse calvaria. Bone cells migrating from fragments of newborn mouse calvaria were used in this study. We also used bone cells obtained by consecutive digestion of the calvaria with enzymes. These bone cells were cultured in fetal calf serum-containing alpha-MEM. IL-1-like cytokine activity was measured by incorporation of [3H]thymidine into C3H/HeJ thymocytes stimulated with PHA. When treated with lipopolysaccharide (LPS) from Escherichia coli 0111 B4, the cultured bone cells produced a significant amount of IL-1-like cytokine. The maximum concentration of IL-1-like cytokine was observed in culture supernatants of the bone cells cultured for 24 hours with the LPS in serum-free medium. The IL-1-like cytokine closely resembles IL-1 in some of its biological characteristics: stimulation of mitogen-induced thymocyte proliferation, stimulation of fibroblast proliferation, pyrogenicity, and molecular weight. These results show that cultured bone cells from newborn mouse calvariae produce an IL-1-like cytokine that closely resembles IL-1.

Animals↗