Biomedical subjects

N Ohno

Publications and source records attributed to N Ohno.

At least 163 records · Page 9Linked to original sources

PubMed1994

Relationship between the tissue distribution and antitumor activity of highly branched (1-->3)-beta-D-glucan, SSG.

Distribution of 3H-labeled (1-->3)-beta-D-glucan([3H]SSG) obtained from the culture filtrate of Sclerotinia sclerotiorum IFO 9395, in various tissues in tumor-bearing mice was examined. [3H]SSG administered intra-peritoneally was mainly detected in liver, spleen, kidney and tumor masses. In contrast to i.p. administration, intra-lesionally administered [3H]SSG was not released from the tumor. Similarly, in a double grafted tumor system, [3H]SSG was located in the administered tumor and not distributed in the distant site tumor, in spite of the fact that significant antitumor effect was shown in both tumor sites in this system. Winn assay confirmed the activation of the systemic antitumor immunity. These results suggested that the distribution of glucans would be one important factor in determining their antitumor effects. However, this would not always be necessary if systemic immunity could be induced.

Animals↗

PubMed1994

Preparation and antigen specificity of an anti-(1-->3)-beta-D-glucan antibody.

Antibody for (1-->6)-branched (1-->3)-beta-D-glucan was prepared using rodents. An antitumor (1-->6)-beta-monoglucosyl branched (1-->3)-beta-D-glucan (GRN: grifolan) was conjugated with bovine serum albumin and used as an immunogen. The antibody titer in serum was determined by ELISA using biotin-conjugated GRN. Administration of the antigen raised the antibody titer only in the rabbit, with mouse and rat showing no significant antibody titer for the glucan. The antigen specificity of the anti-GRN antibody was determined by competitive ELISA. The rabbit anti-GRN antibody bound to structurally related antitumor (1-->6)-branched (1-->3)-beta-D-glucans such as lentinan, schizophyllan and SSG, whereas it did not react with linear (1-->3)-beta-D-glucan, curdlan or GRN-derivatives obtained by periodate-oxidation and Smith degradation. These facts strongly suggest that the hapten site of the antibody was the monoglucosyl branched moiety of (1-->3)-beta-D-glucan. These results indicate that this antibody would be a useful probe for the detection of (1-->6)-branched antitumor glucans administered to the host.

Adjuvants, Immunologic↗

PubMed1994

Enhancement of cytokine production by macrophages stimulated with (1-->3)-beta-D-glucan, grifolan (GRN), isolated from Grifola frondosa.

The ability of grifolan (GRN), a purified fungal (1-->3)-beta-D-glucan, to induce various cytokines from macrophages was examined in vitro. Interleukin-6 (IL-6) activity in supernatants from the culture of macrophage cell line, RAW264.7 was dependent on increasing doses of GRN. The level of IL-6 induced with 500 micrograms/ml of GRN was comparable to that induced with lipopolysaccharide (LPS) 10 micrograms/ml. Enhancement of the mRNA level of IL-6 by treatment with GRN was detected by reverse transcriptase-polymerase chain reaction (RT-PCR). The effect of GRN on production of IL-6 was also observed using peritoneal macrophages from C3H/HeJ mice which did not respond to endotoxins. This data suggested that the ability of GRN to activate IL-6 production of macrophages is not due to contamination of endotoxins in the preparation. Enhanced production of cytokine by GRN was observed not only with IL-6, but also with interleukin-1 (IL-1) and tumor necrosis factor alpha (TNF alpha). In the production of TNF alpha, GRN was more effective than LPS used in this study. Other soluble or gel-forming(1-->3)-beta-D-glucans from various sources did not enhance the production of such cytokines although they are structurally similar to GRN. The above results indicate that GRN is a novel macrophage activator which augments cytokine production without dependence on endotoxins.

Adjuvants, Immunologic↗

PubMed1994

Biological activity and structural characterization of alkaline-soluble polysaccharides from the kernels of Prunus mume Sieb. et Zacc.

The fruits of Prunus mume Sieb. et Zacc. (Japanese name, ume) have been used as a traditional drug and health food. In order to study the active components of P. mume, the polysaccharide fractions were extracted with cold water, hot water and aqueous sodium hydroxide from the kernels of P. mume. We found that some of the polysaccharide fractions exhibited various types of biological activities such as mitogenesis, activation of the alternative pathway of complement and activation of clot formation in human plasma. A polysaccharide, P-1, obtained from the cold 0.5 M NaOH extract was purified by ion-exchange chromatography and gel-filtration, P-1 contained 62.0% neutral sugar as glucose and 38.4% uronic acid (as galacturonic acid), and was free from protein. The neutral sugars of P-1 were arabinose, xylose, rhamnose and galactose in a molar ratio of 9.4:3.4:1.1:1.0, following analysis by gas-liquid chromatography. In addition, galacturonic acid was identified by thin-layer chromatography. The molecular weight of P-1 was found to be more than 2,000,000 by gel-filtration on Toyopearl HW 65F. P-1 showed mitogenic activity towards spleen cells of both C3H/HeN and C3H/HeJ, suggesting that it was free from bacterial endotoxic lipopolysaccharides.

Animals↗

PubMed1994

Changes in immune mediators in mouse lung produced by administration of soluble (1-->3)-beta-D-glucan.

In this study, we showed that systemic administration of SSG, a highly branched soluble (1-->3)-beta-D-glucan obtained from Sclerotinia sclerotiorum, induced immunological changes in the alveolar space of mice in vivo, assessed by analysing some immune mediators in bronchoalveolar lavage (BAL) fluid. A single i.v. administration of SSG (250 micrograms/mouse) induced a rapid but transient leakage of the serum components, IgG and fibronectin, into the alveolar space. This was apparent 12 h post-administration and reached a peak on day 2. Similar kinetic changes were found for lysosomal enzyme activities and interferon gamma (IFN gamma) concentrations in BAL which are markers of activated alveolar macrophages (AMs) or pulmonary T cells. BAL prepared from SSG-treated mice stimulated lysosomal enzyme release from AMs in vitro. However, SSG did not provoke the chronic accumulation of serum proteins in alveoli and did not induce the release of detectable amounts of nitric oxide and the inflammatory cytokines, IL-1, IL-6 and TNF alpha, into BAL. However, their mRNAs were detected in lung tissue using the reverse-transcriptase polymerase chain reaction (RT-PCR) technique. Similar results were observed for multiple i.v. administration (250 micrograms, once a day for 10 consecutive days), and there were a little differences between single and multiple administration. In summary, systemic administration of SSG induces immune responses, including activation of AMs and lymphocytes, but does not provoke chronic inflammation in the alveolar space when administered either as single or multiple doses. This finding is very important for the clinical application of SSG in immunocompromised hosts as a biological response modifier (BRM) without toxic-side effects on lung tissue.

Animals↗

PubMed1994

Analysis of cytokine mRNAs induced by the administration of a highly branched (1-->3)-beta-D-glucan, OL-2.

OL-2, a highly branched (1-->3)-beta-D-glucan, is an antitumor glucan showing strong hematopoietic activity with weaker adjuvant activity than schizophyllan (SPG), another antitumor glucan and one which is used clinically. This paper deals with the gene expression of cytokines in mice by OL-2 and SPG in order to characterize their immunopharmacological activity. Gene expression was examined by a reverse transcriptase-polymerase chain reaction method after intraperitoneal administration of OL-2 or SPG (250 micrograms/mouse). The OL-2 administered mice strongly expressed the interleukin 1 receptor antagonist (IL-1ra) gene but SPG administered mice did not. The difference would be strongly related to the antigen-specific response between OL-2 and SPG. In the genes related to haematopoiesis, OL-2 induced G-CSF and GM-CSF, but SPG induced IL-3. These differences would relate to the pattern of haematopoietic response. Comparing the cytokine gene expression in ICR and AKR mice by OL-2 administration, the changes in cytokine gene expression were less in AKR mice administered OL-2. These findings suggest that the immunopharmacological characteristics of OL-2 are closely related, at least in part, to the activation of the complement system. The data shown in this paper also suggest that cytokine gene expression by beta-glucan would be significantly affected by the structure of these glucans.

Animals↗

PubMed1994

Lysozyme regulates LPS-induced interleukin-6 release in mice.

Bacterial lipopolysaccharide (LPS) stimulates the production and release of endogenous mediators [e.g., tumor necrosis factor (TNF), interleukins-1 and -6 (IL-1 and IL-6), and Platelet Activating Factor [PAF] responsible for the pathophysiologic changes and the mortality associated with sepsis. We recently demonstrated that lysozyme (LZM) bound to LPS (LZM-LPS complex) suppresses LPS-induced tumor necrosis factor-alpha (TNF-alpha) production in vivo. In the present study, we investigated the effect of LZM-LPS complex formation on LPS-induced IL-6 production, both in vitro and in vivo. With the addition of LZM-LPS complex, TNF-alpha and IL-6 release was significantly reduced compared with that by LPS in a dose-dependent manner in mouse macrophage-like cells, RAW264.7. IL-6 production in serum by LPS in carrageenan (CAR)-primed mice peaked at 2 hr following injection. LZM-LPS and LZM-Escherichia coli cell complex (as 1 microgram of LPS per mouse) released significantly reduced concentrations of IL-6 in serum (P < 0.01 and P < 0.001 versus CAR-pretreated LPS- or cell-injected mice). These results emphasize the important role of LZM in vivo in the neutralization of endotoxin. However, in the case of IL-6, by administration of a lethal dose of LPS (as 100 micrograms of LPS per mouse), the IL-6 level was reduced by LZM, but a significant concentration of IL-6 was still released; although the TNF- alpha concentration was negligible in this experimental condition. Thus, it is suggested that LZM might regulate the systemic inflammation induced during Gram-negative bacterial infections by inhibiting the release of cytokines in serum.

Animals↗

PubMed1994

[Antitumor effect of SN-38, active form of CPT-11, on human colorectal cancer cell line].

The in vitro sensitivity testing for four human colorectal cancer cell lines to seven chemotherapeutic drugs including CPT-11, derivative of camptothecin, and its active form SN-38 were determined. MTT assay revealed that SN-38 was the most active for all four cell lines tested and its IC50's were very close to its clinically achievable plasma concentration. Relationship between exposure time and cytocidal effect of SN-38 was also investigated using MTT assay, topoisomerase-I (Topo-I) immunoblot analysis and DNA relaxation-assay, showing that IC50 value, Topo-I protein and Topo-I activity were decreased soon after the administration of SN-38 and reached to the plateau level at 24 hours. We conclude that SN-38 is very potent for colorectal cancer and the optimal schedule of CPT-11 can be the more continuous form of administration capable of as long as 24 hours exposure of its active metabolite, SN-38.

Antineoplastic Agents, Phytogenic↗

PubMed1994

[Oral administration of low-dose etoposide for maintenance chemotherapy in adult T cell leukemia patients].

We studied the effectiveness of low-dose, oral administration of etoposide for maintenance chemotherapy of patients with adult T cell leukemia (ATL). Sixteen patients (9 males and 7 females) in remission (9 in complete remission and 7 partial remission) were orally administered 25 or 50 mg/day of etoposide. Median response duration of all the patients to the therapy was 18.6 months, ranging from 5.0 to 34.0 months. Thirteen out of the 16 patients relapsed, and 9 of them died of tumor progression. Appetite loss occurred in one case, without any other severe side effects. It has been suggested, therefore, that oral administration of the etoposide is useful for maintenance chemotherapy in ATL patients.

Administration, Oral↗

PubMed1993

Suramin selectively inhibits the non-adrenergic non-cholinergic inhibitory junction potential in the guinea-pig stomach.

In smooth muscle cells of the guinea-pig stomach fundus, transmural nerve stimulation evoked a cholinergic excitatory junction potential (e.j.p.) and, in the presence of atropine, a non-adrenergic non-cholinergic (NANC) inhibitory junction potential (i.j.p.). Suramin (> 10(-5) M), a putative inhibitor of the P2 purinoceptor, enhanced the e.j.p. amplitude and inhibited the i.j.p., with no significant effect on the membrane potential. Thus, a possible involvement of ATP in the generation of the NANC i.j.p. has to be considered.

Animals↗

PubMed1993

Expression and function of the interleukin 7 receptor in murine lymphocytes.

A monoclonal antibody, A7R34, that recognizes the high-affinity interleukin 7 receptor (IL-7Ra) and blocks the binding between IL-7 and IL-7Ra has been produced. Cell surface staining with A7R34 demonstrated that IL-7Ra is expressed in both B- and T-cell lineages. In the bone marrow, immature B-lineage cells that do not express surface IgM were IL-7Ra+. In the thymus, IL-7Ra was detected in CD4-8- T cells and also in CD4 or CD8 single-positive cells but not in CD4+8+ double-positive cells. In the peripheral lymphoid tissues, both CD4 and CD8 single-positive cells were the major cell types that express IL-7Ra. Addition of A7R34 to a long-term B-precursor-cell culture inhibited proliferation of the B-lineage cells, indicating that IL-7 is an absolute requirement for in vitro B-cell genesis. Consistent with this in vitro result, continuous injection of A7R34 into an adult mouse resulted in a decrease of B-precursor cells and also of thymocytes, whereas a considerable fraction of mature B and T cells in the peripheral tissues persisted over 2 weeks of the experiment. When A7R34 injection is started from day 14 of gestation, it is possible to produce mice that lack B cells. These results indicate that IL-7 is an essential molecule for generation of both B and T cells in murine bone marrow and thymus, respectively. Moreover, IL-7Ra would be the sole receptor system regulating these processes.

Animals↗

PubMed1993

Heterogeneity of antibodies in Goodpasture syndrome reacting with type IV collagen.

Sera from patients with antiglomerular basement membrane (anti-GBM) antibodies associated with Goodpasture syndrome (GP) or glomerulonephritis were tested by ELISA and electroimmunoblot against whole basement membrane collagen (type IV) isolated from bovine anterior lens capsule (ALC) and bacterial collagenase resistant domains of the collagen molecule, that is, the NC-1 and 7-S domains isolated from either ALC or bovine and human glomerular basement membrane (GBM). Reactivity was high with the NC-1 domain by both the ELISA and the electroimmunoblot techniques. Some of the anti-GBM sera reacted with both the NC-1 and 7-S domains of both human and bovine type IV collagen. At a time when the patients' sera reacted weakly with a collagenase digest of human GBM using a radioimmunoassay, the reactivity with the NC-1 domain was also low, but some of the sera continued to react with the 7-S domain. The data suggest that there may be heterogeneity in the nature of autoantibodies with respect to collagen type IV domain reactivity in the sera of patients with anti-GBM antibody disease.

Animals↗

PubMed1993

Identification of antigenic epitopes in type IV collagen by use of synthetic peptides.

Peptides representing potential antigenic regions of the NC-1 and 7-S domains of the human alpha 1 and alpha 2, and bovine alpha 3 chains of type IV collagen were synthesized either chemically or by the recombinant DNA technique and tested by ELISA using antibodies raised in rabbits against the whole type IV collagen or the NC-1 domain. Sera from patients with Goodpasture syndrome (GP) or with acute poststreptococcal glomerulonephritis (APSGN) were also tested. The location of antigenic determinants was predicted from the primary and secondary structure of the chains, that is, aromaticity, hydrophilicity and presence of beta-turns. All synthetic peptides reacted with the antiserum to type IV collagen (anti-Col IV). Whereas all peptides arising from the NC-1 domain reacted with anti-NC-1, intact 7-S or peptides of the alpha 1 or alpha 2 chain of the 7-S domain did not react. However intact 7-S reacted with anti-Col IV. Two synthetic peptides from the NC-1 domain of alpha 1, (a.a. 71-90 and a.a. 176-190), one from the alpha 2 (a.a. 70-83) and four from the alpha 3 chain (a.a. 72-89, a.a. 104-117, a.a. 133-145, a.a. 185-203) reacted with anti-NC-1 and anti-COL IV. The above peptides, except alpha 3 (72-89) and alpha 3 (185-203), were tested and found to be reactive with sera from patients with GP.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗

PubMed1993

Preparation of in-vivo rat lung model for ischemia-reperfusion injury.

An in-vivo rat lung model for ischemia-reperfusion injury was prepared. The left lung was collapsed after hilar stripping, and the left main pulmonary artery and bronchus were clamped. After the determined period of clamping the left main pulmonary artery and bronchus were declamped and the right main pulmonary artery was clamped. Arterial gas analyses were performed, 1, 10, and 20 minutes after reperfusion. The wet/dry lung eight ratio was calculated and lungs were histologically examined. Before clamping, PaO2 was 102-155 mmHg in all animals. The experimental animals were divided into 4 groups; Group I: temperature 19 degrees C, humidity 55% and duration of clamping 120 minutes (n = 2); Group II: 23 degrees C, 55% and 120 minutes (n = 4); Group III: 23 degrees C, 55% and 90 minutes (n = 5); Group IV: 23 degrees C, 65% and 75 minutes (n = 9). In Group IV, PaO2 decreased significantly in all 9 animals immediately after reperfusion, and at 1, 10, and 20 minutes it was 53.2 +/- 6.1 mmHg, 53.4 +/- 10.2 mmHg, and 67.0 +/- 10.2 mmHg, respectively. Pulmonary edema was observed histologically in 7 of the 9 animals. In-vivo rat lung models for ischemia-reperfusion injury are affected by the surrounding conditions. We established a stable model by setting ischemic time, temperature, and humidity at 75 minutes, 23 degrees C, and 65%, respectively.

Animals↗

PubMed1993

Expression of interleukin 1 family mRNAs by a highly branched (1-->3)-beta-D-glucan, OL-2.

OL-2, a highly branched (1-->3)-beta-D-glucan, is an antitumor glucan showing strong hematopoietic activity with weaker adjuvant activity than schizophyllan (SPG), also an antitumor glucan and one which is clinically used. This paper deals with the gene expression of the interleukin 1 (IL-1) family in mice by OL-2 and SPG in order to characterize the immunopharmacological activity. Gene expression was examined by reverse transcriptase-polymerase chain reaction method. Intraperitoneal administration of OL-2 (250 micrograms/mouse) expressed all three genes of IL-1 alpha, beta, and IL-1 receptor antagonist (IL-1ra) in the peritoneal exudate cells, while SPG induced a strength of IL-1 alpha mRNA comparable to that by OL-2 but a weaker level of IL-1 beta mRNA. SPG did not induce IL-1ra. Similar patterns were seen in spleen and liver by OL-2 or SPG administration. These findings suggest that the immunopharmacological characteristics of (1-->3)-beta-D-glucan are regulated under the gene expression of the IL-1 family.

Animals↗

PubMed1993

Serum components induce beta-D-glucan-inhibitable uptake of zymosan particles by murine peritoneal macrophages.

Effects of murine serum (NMS) treatment on (1-->3)-beta-D-glucan inhibitable uptake of zymosan particles (ZYM) (GIZUP) by murine peritoneal macrophages (PM) and the structural specificity of the inhibition were examined. ZYM uptake by PM treated with NMS was enhanced in comparison with those treated with medium, and in a concentration- and incubation time-dependent manner. The enhanced ZYM uptake was significantly reduced by the pretreatment of PM with soluble (1-->3)-beta-D-glucans. These facts suggest that NMS enhances GIZUP. The effect disappeared by the treatment of NMS with gelatin-Sepharose which removed fibronectin (FN) from the serum, suggesting a significant contribution of FN on GIZUP. In addition, the administration of beta-glucan in vivo elevated the concentration of FN in serum by acute phase response and enhanced GIZUP, suggesting the positive contribution of acute phase responses on beta-glucan mediated immunopharmacological activities. Of particular interest, the inhibition was shown by both antitumor active and inactive glucans. These facts suggested that the recognition of beta-glucans by PM, which would proceed at a relatively early period of whole activation pathways, would not be enough to fully activate the host to show antitumor activity.

Animals↗

PubMed1993

Immunopharmacological characterization of a highly branched fungal (1-->3)-beta-D-glucan, OL-2, isolated from Omphalia lapidescens.

The immunopharmacological activities of a fungal (1-->3)-beta-D-glucan, OL-2, isolated from "Leiwan" Omphalia lapidescens were examined. Intraperitoneal (i.p.) administration of OL-2 to ICR mice induced a significant number of peritoneal exudate cells (PEC) and white blood cells over the period of a few days. Spleen cell numbers were also increased by i.p. administration of OL-2 at about a week. These changes reverted to the normal level within a month. Responses of spleen cells and bone marrow cells (BM) to colony stimulating factors (CSF) were augmented by OL-2 administration assessed by cell proliferation assay. Sera from OL-2 administered mice contained an increased concentration of colony stimulating activity. Gene expressions of interleukin-1 beta, interleukin-6, and tumor necrosis factor alpha in the spleen were also increased. These results suggested the activation of hematopoietic responses, and would well relate to the incremental increase in PEC, white blood cell and spleen cell numbers. OL-2 also increased the serum concentration of fibronectin and complement component C-3. However, OL-2 did not show adjuvant activity to SRBC and antitumor activity against the solid form of Sarcoma 180 by i.p. administration. Yet, OL-2 did not interfere with the antitumor activity of SSG against the same tumor system. These facts suggested that OL-2 could enhance nonspecific host defense mechanisms by enhancing hematopoietic responses, but would not enhance or inhibit the specific immunity mediated by lymphocytes.(ABSTRACT TRUNCATED AT 250 WORDS)

Adjuvants, Immunologic↗

PubMed1993

Inhibitory effect of beta-glucans on zymosan-mediated hydrogen peroxide production by murine peritoneal macrophages in vitro.

Effects of the pretreatment of murine peritoneal macrophages with several polysaccharides on the production of H2O2 induced with unopsonized zymosan were examined. Pretreatment with most of (1-->3)-beta-D-glucans for 6 h at 37 degrees C inhibited the zymosan-mediated H2O2 production by macrophages. The phorbol myristate acetate (PMA)-mediated H2O2 production was not affected by the pretreatment. The pretreatment of macrophages with (1-->3)-beta-D-glucans decreased the ability to ingest unopsonized zymosan, but did not affect the ingestion of IgG-coated sheep red blood cells (IgG-SRBC). These results suggested that the pretreatment with (1-->3)-beta-D-glucans interfered with the interaction of macrophages to zymosan and that the occupation of the receptor for the (1-->3)-beta-D-glucans inhibited zymosan-mediated production of H2O2 by macrophages. Chemical modification by substitution with carboxymethyl groups or hydroxyethyl groups of a (1-->6)-branched (1-->3)-beta-D-glucan reduced the inhibitory effect of pretreatment on zymosan-mediated H2O2 production. The above results indicated the possibility that murine peritoneal macrophages possess certain receptors for beta-anomeric glucans, and one ligand specificity of the receptors is to restrict the intact (1-->3)-beta-D-glucosyl back bone.

Animals↗