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F Sendo

Publications and source records attributed to F Sendo.

At least 91 records · Page 5Linked to original sources
PubMed1988

Enhancement by recombinant interferon-gamma of spontaneous tumor cytostasis by human neutrophils.

Human peripheral neutrophils treated with recombinant human interferon-gamma (IFN) inhibited tritiated thymidine (3H-TdR) uptake by various tumor cells. The concentration-response curve of IFN required for induction of cytostatic activity of neutrophils showed two peaks. Short time incubation of neutrophils with IFN at 4 degrees C was sufficient for inducing neutrophil cytostasis. When neutrophils pretreated with IFN for 5 min at 4 degrees C were further treated with trypsin, cytostasis by the treated neutrophils was decreased depending on the concentration of trypsin, whereas cytostasis by neutrophils pretreated with IFN for 180 min at 37 degrees C was not inhibited by trypsin treatment. Cytostatic activity induced by IFN was inhibited by pretreatment of IFN with anti-IFN-monoclonal antibody.

Animals↗
PubMed1987

Production of factor(s) that render polymorphonuclear leukocytes cytostatic from spleen cells stimulated with a streptococcal preparation, OK-432.

We previously reported the augmentation of tumor cytotoxicity of polymorphonuclear leukocytes (PMN) by in vivo administration of a streptococcal preparation, OK-432 (S. Watabe et al., J. Natl. Cancer Inst., 72: 1365-1370, 1984). The present study was undertaken to elucidate the mechanisms of the phenomena. Mouse and rat spleen cells were stimulated in vitro with OK-432. The culture supernatants from the stimulated spleen cells (OK sup) contained factor(s) that rendered mouse and rat PMN cytostatic [neutrophil activating factor (NAF)]. The stimulation of spleen cells with a small dose of OK-432 (0.05 micrograms/ml) resulted in the production of maximum NAF, and NAF was produced soon (12 h) after OK-432 stimulation. NAF was partially inactivated with 60 degrees C 30-min treatment, and completely inactivated with 100 degrees C 10 min. NAF was sensitive to pH 2 treatment. The treatment of PMN with OK sup for 5 min at 37 degrees C was sufficient to induce cytostatic activity of PMN. That OK sup contained gamma-interferon and recombinant gamma-interferon showed NAF activity indicate that gamma-interferon is a NAF in OK sup.

Animals↗
PubMed1987

In vivo antitumor effect of lymphokine-activated rodent polymorphonuclear leukocytes.

In vivo tumor inhibitory activity of polymorphonuclear leukocytes (PMN) treated in vitro with lymphokine(s) (LK) was investigated with Winn's assay. Culture supernatants of BALB/c mouse spleen cells incubated with a streptococcal preparation, OK-432, were used as an LK source. With the use of a [3H]uridine release assay, RL male-1 tumor cells were lysed to some extent by peritoneal BALB/c mouse PMN treated with this LK preparation. With Winn's assay, LK-treated PMN from BALB/c mice completely inhibited the growth of the admixed syngeneic tumor at a high effector to target ratio, when normal mice were used as recipients. When X-irradiated mice or nude mice were used as recipients, the tumor growth was partially inhibited by admixed LK-treated PMN, but the tumor began to grow gradually and finally killed the recipient mice, even when a high effector target ratio was used. When nude mice which had been given i.v. transfers of nylon wool column effluent spleen cells were used as recipients, the tumor inhibitory activity of LK-treated PMN was recovered to the same level as when normal mice were used as recipients. On the other hand, tumor inhibition by admixed LK-treated PMN in nude mice was not recovered by the transfer of X-irradiated nylon column effluent T-cells. As a mechanism of tumor inhibition by LK-treated PMN, a possible role of LK-treated PMN in reduction of tumor load is discussed.

2-Chloroadenosine↗
PubMed1987

Tumor cytotoxicity of polymorphonuclear leukocytes in beige mice: linkage of high responsiveness to linear beta-1,3-D-glucan with the beige gene.

Beige mice (bg/bg) have many functional defects in their leukocytes and these phenotypes are inherited autosomal recessively. We studied the tumor cytotoxicity of polymorphonuclear leukocytes (PMN) obtained from bg/bg. The intensity of tumor cytotoxicity of PMN induced by linear beta-1,3-D-glucan was significantly higher in bg/bg PMN than in PMN of heterozygous control mice (bg/+). To analyze this phenomenon more precisely from the genetic viewpoint, we determined the tumor cytotoxicity of PMN from mice obtained by several mating experiments. (a) The intensity of linear beta-1,3-D-glucan-induced PMN cytotoxicity was found to be genetically defined and linked completely with the beige gene. In litter mates obtained from bg/+(female) X bg/bg(male), bg/bg(female) X bg/+(male), and bg/+(female) X bg/+(male) mating, PMN from only bg/bg showed significantly higher tumor cytotoxicity than those from bg/+ or mice that do not possess the beige gene (+/+). (b) The tumor cytotoxicity induced by other stimulants (phorbol myristate acetate and cytokines) was not significantly higher in bg/bg than bg/+ or +/+ PMN. It was concluded that the high responsiveness to linear beta-1,3-D-glucan in terms of tumor cytotoxicity of PMN was determined by the locus that is linked to the beige gene and is expressed autosomal recessively.

Animals↗
PubMed1987

T cell mitogenicity of a novel beta-D-galactoside-specific lectin from the beetle, Allomyrina dichotoma (allo A).

We examined the lymphocyte mitogenicity of a novel beta-D-galactoside-specific lectin from the beetle Allomyrina dichotoma, named allo A. Allo A was mitogenic to spleen cells of various strains of mice and rats and to human peripheral blood lymphocytes. When the selectivity of mitogenicity to T or B lymphocytes was examined with mouse spleen cells, allo A was selectively mitogenic to T-enriched spleen cells, which indicates that allo A is a T cell mitogen. Thymocytes from non-treated mice hardly responded to allo A, while those from cortisone-treated mice did to a great extent, indicating that allo A is mitogenic to mature thymocytes. The lymphocyte activation with allo A was inhibited by lactose, but not by melibiose, N-acetyl-D-glucosamine, or methyl-alpha-D-mannoside, which suggests that cell surface molecules containing beta-D-galactosyl residues are of importance in the structure of allo A receptors on the cell surface.

Animals↗
PubMed1987

A monoclonal antibody reacting with the zona pellucida of the oviductal egg but not with that of the ovarian egg of the golden hamster.

A monoclonal antibody (mAb) designated AZPO-8 was produced by hybridizing a mouse myeloma with spleen cells from BALB/c mice immunized with materials obtained from the hamster oviduct. With an immunofluorescence test, AZPO-8 reacted with the zona pellucida (ZP) of ovulated eggs in the oviduct (ZP-OVI) but not with the zona pellucida of eggs in the ovary (ZP-OVA). Using indirect enzyme immunostaining, this mAb reacted with epithelial cells of the oviduct, the uterus (especially the cervical epithelium) and the gastric mucosa, but not with other hamster tissues examined. The reactivity of antigen-positive tissues was abrogated by pretreatment of the tissues with periodic acid. Western blotting analysis revealed that AZPO-8 reacted with substances of broad molecular weight range, and the strongest reactivity was detected at a molecular weight of approximately 200,000 in both cases when extract of ZP-OVI or the hamster oviduct was applied on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) gel. AZPO-8 showed strong hemagglutination activity only to group A human red blood cells. These results indicated that (1) ZP-OVI had an antigen that was not detected on ZP-OVA, (2) ZP-OVI and the oviduct shared the same antigenicity, and (3) the antigenic determinant reactive with the mAb might be carbohydrate in nature. A possible role of this antigen in fertilization was discussed.

Animals↗
PubMed1987

Studies on the immunological disturbance in murine schistosomiasis japonica from the viewpoint of the interleukin cascade reaction.

We examined the mechanisms of disturbed T-lymphocyte function that occurred during Schistosoma japonicum infection of BALB/c mice from the viewpoint of the interleukin cascade reaction. Each point of the interleukin cascade reaction was examined. First, IL-1 production by adherent peritoneal or spleen cells, as a source of macrophages, was normal or rather enhanced during the infection, the values being 100-180% of the control. Secondly, proliferative response to exogenous IL-1 of thymocytes from S. japonicum-infected mice progressively decreased during 3-7 weeks of infection. Thirdly, IL-2 production of S. japonicum-infected mice was significantly inhibited, even at 2 weeks of infection, and the activity was 10-20% of the control at 5-8 weeks of infection. Diminished IL-2 production was not caused by suppressive factors, such as PGE2 or suppressor macrophages, or a decrease in the number of IL-2 producing T cells. Finally, the response to exogenous IL-2 in S. japonicum-infected mice was suppressed markedly by 4 weeks of infection, and the responsiveness was reduced to 20% of the control at 8 weeks of infection. The mechanisms of disturbances in T-cell functions in S. japonicum-infected mice are discussed.

Animals↗
PubMed1986

Enhancement of the expression of a rat neutrophil-specific cell surface antigen by activation with phorbol myristate acetate and concanavalin A.

A monoclonal antibody against rat neutrophils, RP-1, was produced by hybridizing a mouse myeloma (P3-X63-Ag8.653) with BALB/c mouse spleen cells sensitized with peritoneal neutrophils from Wistar-King-Aptakeman/Hok rats. RP-1 specifically reacted to neutrophils and bone marrow cells from rats of various strains. The expression of an antigen reactive to RP-1 on rat peritoneal neutrophils was enhanced by stimulation with phorbol myristate acetate and concanavalin A. The experimental result that the expression of an antigen reactive with another anti-neutrophil monoclonal antibody was not enhanced by stimulation with phorbol myristate acetate indicates that the antibody-binding capacity of stimulated neutrophils was not nonspecifically enhanced. The enhancement of antigen expression was temperature dependent. A glycolytic inhibitor, 2-deoxy-D-glucose, and an inhibitor of intracellular calcium mobilization, 3,4,5-trimethoxybenzoic acid 8-(diethylamino)-octyl ester hydrochloride, which inhibited hydrogen peroxide release from stimulated neutrophils, did not inhibit enhancement of the expression of an antigen reactive with RP-1.

Animals↗
PubMed1986

Heterogeneous profiles of a factor that renders neutrophils cytotoxic obtained from a concanavalin A-stimulated spleen cell culture in partial purification process.

Concanavalin A (Con A)-stimulated rat spleen cells were cultured in a serum-free conditioned medium. This culture supernatant contained a certain factor(s) that renders neutrophil cytotoxic for various tumor cells. The factor was tentatively termed neutrophil-activating factor (NAF). Rat NAF was partially purified from the serum-free culture supernatant by using ion exchange chromatography of DEAE-Sephadex A-50, gel filtration of Sephadex G-100, and affinity chromatography of Con A-Sepharose 4B. NAF activity was eluted in broad fractions by the ion exchange chromatography and the gel filtration. Moreover, on the Con A column, some NAF activities were bound to the column, but other activities passed through the column. These results showed the heterogeneity or polydispersity of NAF activity in both molecular size and charge-based separation properties. Monoclonal antibodies were produced by fusing BALB/c myeloma cells (P3-X63 Ag8.653) with spleen cells from syngeneic mice immunized with partially purified NAF (pNAF) obtained from the gel filtration. Absorbent beads which were linked with one monoclonal antibody (ANAF-10) partially absorbed NAF activity from supernatants of a Con A-stimulated spleen cell culture. Further purification of pNAF was performed with the use of affinity chromatography of ANAF-10-linked Sepharose. Through these procedures, the NAF activity was concentrated about 10,000-fold. Heterogeneity of NAF activity, however, did not disappear in even this affinity chromatography. On the other hand, 125I-labeled material of the final product migrated to one major band corresponding with an m.w. of about 20,000 as determined by SDS-PAGE analysis, and NAF activity was detected in the same band.

Animals↗
PubMed1986

A T cell leukemia line produces factor(s) that render rat neutrophils cytotoxic.

Proteose-peptone-induced intraperitoneal neutrophils from rats were activated in terms of tumor cytotoxicity by pretreatment with culture supernatants from a human T cell leukemia line, Jurkat (culture sup). Culture sup-treated neutrophils showed cytotoxicity against various tumor cell lines. The cytotoxicity of culture sup-treated neutrophils was dependent on the number of neutrophils and the concentration of culture sup. Cytostasis by activated neutrophils was observed very early in the assay incubation period (within 6 hr), but cytolysis first occurred at 24 hr after the start of incubation. Factor(s) in culture sup responsible for the activation of cytotoxic neutrophils were stable to temperature and pH treatments, and their molecular weight was higher than 10,000. The responsible factor(s) for activation of cytotoxic neutrophils were different from interleukin-2, serum-derived factor, and bacterial lipopolysaccharide.

Animals↗
PubMed1985

Inhibition of mouse natural killer cytotoxicity by heparin.

The effect of heparin on mouse natural killer (NK) cytotoxicity was investigated. Heparin greatly inhibited NK activity at a concentration of more than 10 units/ml. Inhibition of NK cytotoxicity was observed only when heparin was present in the reaction mixture of the cytotoxicity assay. The results of kinetic study of NK inhibition and target-effector binding assay proposed the possibility that heparin inhibits NK cytotoxicity after the binding of effector cells to target cells. Dextran sulfate, the heparin analog, which has potent negative charge also had an inhibitory effect on NK activity. Fractionation of heparin on Sephadex A-25 column revealed the parallelism of the negative charge and the inhibitory effect of heparin on NK cytotoxicity. These results demonstrated that polyanion could modulate NK cytotoxicity.

Animals↗
PubMed1985

Characteristics of the anti-sheep red blood cell heterophile antibodies produced during Schistosoma japonicum infection in mice.

Heterophile antibodies (Ab) against sheep red blood cells were shown to have developed in mice experimentally infected with Schistosoma japonicum (SJ). Incidence of the elevated Ab levels was markedly high in the period of 6-10 weeks following infection. By means of absorption tests, the heterophile Ab could be distinguished from classical human heterophile Ab of Paul-Bunnell, Hanganutzui-Deicher, and Forssman types. Antigen(s) cross-reactive with the heterophile Ab was found only in goat red blood cells (RBC) but absent on RBC of other species, in various tissue homogenates of syngeneic mice, or in SJ parasites and their eggs. The Ab activity seems to be mainly localized in immunoglobulin classes other than IgM.

Absorption↗
PubMed1985

Decreased response to interleukin-2 of cancer patients in terms of augmentation of natural killer cell activity.

The effects of interleukin-2 (IL-2) on natural killer (NK) cell activity were examined in both healthy persons and cancer patients. The NK activity of peripheral blood lymphocytes from 29 healthy donors was augmented by IL-2 treatment in all cases. However, in 14 out of 50 cancer patients NK activity was not augmented by IL-2. The rate of NK augmentation in a group of cancer patients was significantly lower than that in a healthy control group. When the cancer patients were divided into each clinical stage, NK augmentation was as follows: in stage I, 3 out of 3; in stage II, 11 out of 12; in stage III, 10 out of 18; and in stage IV, 12 out of 17. The rate of NK augmentation was significantly lower in cancer patients of stages III and IV. The rate of NK augmentation was also dependent on the performance status (PS) of cancer patients. The NK augmentation of cancer patients of PS 0 to 2 was not significantly different from that of normal controls, whereas the rate of NK augmentation was significantly lower in cancer patients of PS 3 and 4.

Digestive System Neoplasms↗
PubMed1984

Carbohydrates as antigenic determinants of tumor-associated antigens recognized by monoclonal anti-tumor antibodies produced in a syngeneic system.

Two monoclonal antibodies (KH-1 and KH-2) against a transplanted fibrosarcoma (KMT-17) in WKA rats were produced by fusing a mouse myeloma (P3-X63-Ag8.653) with spleen cells from syngeneic rats hyperimmunized with KMT-17. Both antibodies showed complement-dependent cytotoxicity against KMT-17. By absorption of cytotoxicity, KH-1 reacted with homologous tumor, other syngeneic fibrosarcomas (KMT-80 and KMT-75), and lung and kidney from normal rats. However, KH-2 reacted with many kinds of tumors and various normal tissues. Antigen specificity was tested by complement fixation and/or solid-phase radioimmunoassay using glycolipids isolated from KMT-17 cells and authentic glycolipids. KH-1 reacted with globotriglycosyl ceramide which was not detected on KMT-17 cells and in cross-reacted weakly with IV3-alpha-galactosyl-lactoneotetraglycosyl ceramide, one of the major glycolipids of KMT-17. The immune reaction was inhibited by alpha-methyl-galactose. KH-2 reacted with lactosyl ceramide and lactoneotetraglycosyl ceramide. The reaction was more potently inhibited by lactose than by beta-methyl-galactose. Antibodies with similar specificity to either KH-1 or KH-2 were elevated in syngeneic rat sera after serial immunization with viable KMT-17 cells.

Animals↗
PubMed1984

The presence of anti-sheep red blood cell heterophile antibodies and their characteristics in murine schistosomiasis japonica.

Sensitive methods of an enzyme-linked immunosorbent assay (ELISA) using red blood cells (RBC) have been developed and were applied to the detection of anti-sheep red blood cell (SRBC) heterophile antibodies (Ab) present in sera of Schistosoma japonicum (SJ)-infected mice. The indirect hemagglutination test (IHA) was used for the purpose as well. By these methods a significant increase in the heterophile Ab levels was demonstrated in the mice particularly after 6-10 weeks of infection. The heterophile Ab in SJ-infected mice were predominantly immunoglobulins resistant to 2-mercaptoethanol treatment and had temperature-independent reactivity. In an attempt to investigate the immunological specificity of the heterophile Ab, various absorption tests were performed; Davidsohn's differential absorption test revealed that the heterophile Ab were distinct from Forssman antibody, Paul-Bunnell antibody and heterophile agglutinins known to appear in serum sickness. The heterophile Ab were absorbed only with SRBC and goat red blood cells, not with other species of RBC such as human O Rh-, O Rh+, A Rh+, B Rh+, mouse, ox, chicken, horse, rabbit, guinea pig, and rat RBC, or syngeneic tissue homogenates including brain, lung, liver, spleen, kidney, muscle, and thymus. This heterophile antibody response is not a consequence of a specific immune response directed to the antigens of SJ parasites, since absorption of the heterophile Ab with SJ adult worms or an egg preparation did not reduce the heterophile Ab level.

Animals↗
PubMed1984

Hemolytic factors in Schistosoma japonicum eggs.

Extracts of Schistosoma japonicum eggs were found to exhibit hemolytic activity on erythrocytes of various species. The hemolytic reaction took place more rapidly at 37 degrees C than at 4 degrees C and did not require divalent cations. The degree of hemolysis was dependent on the concentration of the egg extracts. The hemolytic factors seemed to be lipid in nature because of being heat-stable and soluble in chloroform solvent. Further analysis by means of thin-layer chromatography showed that hemolytic activity in the extracts was due to free fatty acids. Analysis by gas chromatography revealed that fatty acids in the egg extracts consist of myristic, palmitic, palmitoleic, stearic, oleic, linoleic, linolenic, and arachidonic acids. Among them, based on the experiments with commercially available fatty acids, arachidonic acid was the most intensively hemolytic, followed by linoleic, linolenic, oleic, palmitoleic, and myristic acids in that order, whereas palmitic acid showed weak activity only in the presence of divalent cations. From the estimated calculation, it was assumed that 1 mg of protein of the egg extracts contains as much as 0.22 mg of free fatty acids.

Animals↗