Immunopharmacological studies on TBX, a new antiallergic drug (1). Inhibitory effects on passive cutaneous anaphylaxis in rats and guinea pigs

The effects of 9-methyl-3-(1H-tetrazol-5-yl)-4H-pyrido[1,2-a]pyrimidin-4-one potassium salt (TBX), a new antiallergic drug, on passive cutaneous anaphylaxis (PCA) mediated by homologous IgE or IgG antibody were investigated in rats and guinea pigs. TBX (i.v. and p.o.) clearly inhibited IgE- and IgGa-mediated homologous PCAs in rats, without showing any inhibition of the skin reactions caused by histamine, serotonin and bradykinin in contrast to the inhibition of prostaglandin E1-induced skin reaction. Neither adrenalectomy nor propranolol treatment modified TBX's inhibition of the former PCA. With regard to tachyphylaxis to TBX, it was demonstrable in IgE-mediated homologous PCA in rats when they were pretreated with TBX (0.5 mg/kg, i.v.), followed 60 min later by a second dose of the drug (0.05 mg/kg, i.v.). There was no cross-tachyphylaxis between disodium cromoglycate (DSCG) and TBX. Homologous PCA caused by guinea pig IgE was also inhibited in a dose-dependent fashion by i.v. and p.o. administrations of TBX, although higher doses of TBX were needed to inhibit guinea pig PCA than the rat one. Interestingly, TBX showed more potent inhibition of both rat and guinea pig homologous PCAs than DSCG or tranilast. The results obtained indicate that TBX is an orally effective antiallergic agent displaying no antagonistic actions on the chemical mediators released.

Immunopharmacological studies on TBX, a new antiallergic drug (2). Inhibitory effects on histamine release from peritoneal mast cells and lung fragments of rats

The ability of 9-methyl-3-(1H-tetrazol-5-yl)-4H-pyrido[1,2-a]pyrimidin-4-one potassium salt (TBX) to inhibit histamine release from both peritoneal exudate cells (PEC) containing mast cells and lung fragments of rats was investigated in vitro. Low concentrations of TBX dose-dependently inhibited IgE-mediated histamine release from PEC of passively sensitized animals; its IC50 was 5.1 x 10(-9) g/ml. When TBX was added simultaneously with the antigen challenge, the highest inhibition was obtained. In contrast, extension of preincubation time with the agent resulted in a marked decrease in the inhibition of histamine release. The potent inhibition of histamine release by TBX was observed equally in glucose-free as well as complete Tyrode's solution, whereas TBX reduced its inhibitory action in Ca2+-free or D2O-supplemented medium. In addition, TBX inhibited compound 48/80- but not calcium ionophore A23187-induced histamine release from normal PEC. With regard to the intracellular cyclic AMP level in normal PEC, it was significantly enhanced by a high concentration of TBX (10(-3) g/ml). TBX also inhibited antigen-induced histamine release from lung fragments of actively immunized animals. Interestingly, TBX displayed non-competitive inhibition of cyclic AMP-dependent phosphodiesterase derived from lung homogenates; its K1 value was 8.70 x 10(-4) M.

[Antiallergic effects of mequitazine. 2. In vivo experiments]

Antiallergic effects of mequitazine were investigated in vivo and compared with those of ketotifen and disodium cromoglycate (DSCG). The results obtained were as follows: 1) Mequitazine in doses of 2 and 5 mg/kg given, p.o., 1 hr prior to antigen challenge inhibited dose-dependently the 48-hr passive cutaneous anaphylaxis in rats. Five mg/kg of mequitazine showed almost the same extent of inhibitory activity as that of 1 mg/kg of ketotifen. An i.v. administration of 1 mg/kg DSCG 1 min before antigen challenge also showed a marked inhibition. 2) The experimental asthma induced by challenge with an i.v. injection of antigen in passively sensitized guinea pigs was fairly inhibited by the pretreatment with 5 mg/kg of mequitazine administered p.o., although 2 mg/kg of this drug showed only a slight inhibition. 3) The experimental asthma induced by aerosolized antigen was also fairly inhibited by the pretreatment with 5 mg/kg of mequitazine given p.o.

[Antiallergic effects of mequitazine. 1. In vitro experiments]

The antiallergic effects of 10-(3-quinuclidinylmethyl)phenothiazine (mequitazine) were investigated in vitro. The results obtained were as follows: 1) In the isolated trachea and lung parenchyma of guinea pigs, mequitazine showed a fairly potent antagonistic action against contractions induced by both histamine (Hi) and acetylcholine (ACh). Mequitazine was much less potent in antihistaminic action and slightly more potent in anticholinergic action than ketotifen. The contractions of the preparation by leukotriene (LT) D4 were antagonized by mequitazine, although the potency was moderate, showing an IC50 value of 2.3 x 10(-5) g/ml in the trachea and 5.1 x 10(-5)g/ml in the lung parenchyma. Mequitazine had no effect on the contraction of the trachea by PGF2 alpha, but inhibited that of the lung parenchyma with pA2 = 7.0. 2) Mequitazine (10(-6) g/ml) slightly inhibited the Schultz-Dale reaction of the isolated guinea pig trachea, while ketotifen at the same concentration did not show any effect. 3) The contraction of the isolated guinea pig trachea by Ca2+ influx was slightly inhibited by mequitazine (10(-5) g/ml). 4) Mequitazine competitively inhibited the cyclic AMP-dependent phosphodiesterase activity from the rat lung with a potency of 10 times and 5 times more than those of ketotifen and theophylline, respectively. 5) Mequitazine (10(-6) to 10(-5) M) suppressed both the anaphylactic and phospholipase A2-induced histamine release from the peritoneal cells of rats. 6) Mequitazine (10(-5) g/ml) also inhibited the anaphylactic and Ca ionophore-induced histamine release from the leukocytes of the atopic patients and normal subjects. 7) The anaphylactic releases of histamine, LTB4 and peptide LT from the human lung fragments were dose-dependently inhibited by mequitazine (10(-7) approximately 10(-5) g/ml).

Antitumor activity, mitogenicity, and lethal toxicity of chemically synthesized monosaccharide analogs of lipid A

Antitumor activity of three derivatives of chemically synthesized diacyloxyacylglucosamine-4-phosphate (acyl-GlcN-4P) linked 3-deoxy-D-manno-2-octulosonic acid (KDO) and 12 derivatives of acyl-GlcN-4P or acyloxyacylglucosamine-6-phosphate (acyl-GlcN-6P) with chiral acyloxyacyl groups at the C-2 and C-3 positions was examined. Ehrlich carcinoma cells (1 x 10(4] were inoculated i.p. into ddY mice on day 0, and these compounds (100 micrograms/d/mouse) were administered i.p. on days -5, -2, +1, +3, and +5. Although the antitumor activity of the acyl-GlcN-4P linked KDO was weaker than that of the natural lipopolysaccharide, groups of mice administered A-301 with di-3-hexadecanoyloxytetradecanoyl [(R)C14-O-C16] at C-2, -3, and A-303 with di-3-tetradecanoyloxytetradecanoyl [(R)C14-O-C14] showed longer mean survival times than the control group. However, KDO-attachment appeared not to enhance the antitumor activity of acyl-GlcN-4P. The group of mice administered acyl-GlcN-4P (A-145) or acyl-GlcN-6P (A-144 and A-146), which have an acyloxyacyl group at C-2, -3, showed prolonged survival times when compared to the control group, but the differences were not significant. On the other hand, when compound A-107 with [(S)C14-O-C14] at the C-2 position and 6-phosphate was administered to 5 mice, 3 mice survived for 25 d. Furthermore, mitogenicity for splenocytes of C57BL/6 mice and lethal toxicity in C57BL/6 mice sensitized with D-galactosamine were observed with the acyl-GlcN-4P or -6P derivatives with (R) or (S) isomers of fatty acid.(ABSTRACT TRUNCATED AT 250 WORDS)

Biological activities of chemically synthesized N-acetylneuraminic acid-(alpha 2----6)-monosaccharide analogs of lipid A

The mitogenicity and lethal toxicity of chemically synthesized lipid A analogs, in which 2,3-acyloxyacylglucosamine-4-phosphate linked to tetraacetyl-N-acetylneuraminic acid (compound A-207) or to N-acetylneuraminic acid (compound A-307), were examined. Although the mitogenic activity of the synthetic compounds was weaker than that of bacterial LPS, doses of 10-50 micrograms/ml of A-207 and 5-10 micrograms/ml of A-307 were capable of increasing incorporation of [3H]thymidine into cultured spleen cells of C57BL/6 mice. Lethal toxicity of A-207 was observed at 10 micrograms/mouse in C57BL/6 mice sensitized with D-galactosamine hydrochloride. However, the attachment of tetraacetyl-N-acetylneuraminic acid or N-acetylneuraminic acid does not appear to enhance the biological activity of acyloxyacylglucosamine-4-phosphate.

Immunopharmacological actions of the new antiallergic drug butyl 3'-(1H-tetrazol-5-yl)oxanilate. 5th communication: effects on immunological reactions in mice and humans

The effects of butyl 3'-(1H-tetrazol-5-yl)oxanilate (WP-833), a new antiallergic drug, on immunological reactions in mice and humans were studied in view of possible side effects. Hemagglutinin formation in mice immunized with sheep red blood cells was not suppressed by WP-833 administered i.p. or p.o. for 3 days either before or after immunization. In addition, the same treatments with WP-833 showed no suppression of hapten-specific immunoglobulin E (IgE) or immunoglobulin G (IgG) antibody formation in mice immunized with dinitrophenyl-conjugated ovalbumin mixed with alum. The proliferation of human peripheral blood lymphocytes induced by concanavalin A, phytohemagglutinin-P, pokeweed mitogen, protein A or Cowan I was not suppressed by WP-833. Nitroblue tetrazolium reduction test, phagocytosis and chemotaxis in human neutrophils were not inhibited by WP-833.

Immunopharmacological actions of the new antiallergic drug butyl 3'-(1H-tetrazol-5-yl)oxanilate. 3rd communication: inhibitory effects on histamine release from lung fragments, Schultz-Dale reaction in isolated tracheal muscle and experimental asthma in guinea pigs

The inhibitory effects of butyl 3'-(1H-tetrazol-5-yl) oxanilate (WP-833), a new antiallergic drug, on histamine release from lung fragments, Schultz-Dale (SD) reaction in isolated tracheal muscle and experimental asthma were investigated in guinea pigs passively sensitized with homologous immunoglobulin E (IgE) serum. WP-833 dose-dependently inhibited antigen-induced histamine release from lung fragments. In addition, synergism as to inhibition of histamine release was observed with a combination of WP-833 and isoprenaline but not with that of WP-833 and theophylline. WP-833 also inhibited antigen-mediated SD reaction of isolated tracheal muscle without showing antagonistic actions upon histamine- and leukotriene D4-induced contraction of normal tracheal muscle. Experimental asthma was clearly inhibited in a dose-dependent fashion by oral administration of WP-833.

Immunopharmacological actions of the new antiallergic drug butyl 3'-(1H-tetrazol-5-yl)oxanilate. 1st communication: effects on type I to type IV allergic reactions in animal models

The effects of butyl 3'-(1H-tetrazol-5-yl)oxanilate (WP-833), a new antiallergic drug, on type I to type IV allergic reactions were investigated by employing various animal models. WP-833 (i.v. and p.o.) dose-dependently inhibited homologous or heterologous passive cutaneous anaphylaxis (PCA) mediated by rat or mouse immunoglobulin E (IgE) in rats. Homologous PCA caused by guinea pig IgE was also inhibited by WP-833. In addition, WP-833 had inhibitory actions upon homologous PCA induced by rat or guinea pig IgG. However, WP-833 showed no inhibition of rat skin reactions caused by histamine, serotonin and bradykinin, contrasting with the inhibition of prostaglandin E1-induced skin reaction. Furthermore, both adrenalectomy and propranolol treatment exerted no influences on the inhibition of IgE-mediated homologous PCA in rats by WP-833. In contrast to above findings demonstrating that WP-833 clearly inhibited type I allergic reaction, systemic Forssman shock in guinea pigs and reversed cutaneous anaphylaxis in rats (type II), passive Arthus reaction in rats (type III), and contact dermatitis and tuberculin reaction in mice (type IV) were unaffected by WP-833 even in higher doses than in those capable of completely inhibiting type I allergic reaction.

Immunopharmacological actions of the new antiallergic drug butyl 3'-(1H-tetrazol-5-yl)oxanilate. 4th communication: effects on histamine release from human leukocytes and from human and monkey lung fragments

The effects of butyl 3'-(1H-tetrazol-5-yl)oxanilate (WP-833), a new antiallergic drug, on histamine release from human leukocytes and from human and monkey lung fragments were investigated. WP-833 showed no inhibition of antigen, anti-immunoglobulin E (IgE)- and calcium ionophore A23187-induced histamine release from leukocytes of atopic patients allergic to house dust mite. In addition, no influences of WP-833 on the levels of cyclic adenosine monophosphate and guanosine monophosphate in leukocytes from healthy subjects were observed. However, antigen- or anti-IgE-mediated histamine release from human and monkey lung fragments passively sensitized in vitro with human serum IgE sensitive to mite antigen was clearly inhibited by WP-833. Interestingly, prolonged pretreatment of lung fragments with WP-833 resulted in a decay in inhibition of anaphylactic histamine release. Spontaneous histamine release from human leukocytes and monkey lung fragments were not inhibited by WP-833.

Immunopharmacological actions of the new antiallergic drug butyl 3'-(1H-tetrazol-5-yl)oxanilate. 2nd communication: inhibitory effects on histamine release from rat mast cells and lung fragments

The effects of butyl 3'-(1H-tetrazol-5-yl)oxanilate (WP-833), a new antiallergic drug, on its ability to inhibit histamine release from both peritoneal mast cells and lung fragments of rats were investigated. WP-833 inhibited in a dose-dependent fashion immunoglobulin E (IgE)-mediated histamine release from mast cells. Such potent inhibition was observed in glucose-free as well as complete Tyrode's solution but neither in Ca2+-free nor D2O-supplemented Tyrode's solution. In addition, WP-833 significantly increased intracellular cyclic adenosine monophosphate (AMP) levels in purified mast cells. On the other hand, WP-833 inhibited compound 48/80-but not calcium ionophore A23187-induced histamine release from normal mast cells. Also both IgE- and IgG-mediated histamine release from lung fragments were inhibited by WP-833. WP-833 showed non-competitive inhibition of cyclic AMP-dependent phosphodiesterase derived from lung preparations.

Biological activities of chemically synthesized 2-keto-3-deoxyoctonic acid-(alpha 2----6)-D-glucosamine analogs of lipid A

The mitogenicity, lethal toxicity, and Shwartzman reaction of three derivatives of chemically synthesized 2-keto-3-deoxyoctonic acid-linked 2,3-diacyloxyacylglucosamine-4-phosphate (KDO-GlcN-4-P) were determined. The compounds, A-301 (with di-3-hexadecanoyloxytetradecanoyl at the C-2 and C-3 positions), A-303 (di-3-tetradecanoyloxytetradecanoyl), and A-305 (3-dodecanoyloxytetradecanoyl and 3-tetradecanoyloxytetradecanoyl), induced a significant incorporation of [3H]thymidine into splenocytes of C57BL/6 mice. The compounds A-301 and A-303 showed lethality at a high dose of 50 micrograms per mouse in C57BL/6 mice sensitized with D-galactosamine, whereas A-305 caused toxicity even at a dose of 10 micrograms per mouse. However, the three compounds did not elicit the local Shwartzman reaction in rabbits. These findings indicate that the addition of 2-keto-3-deoxyoctonic acid enhances the mitogenic activity of 2,3-diacyloxyacylglucosamine-4-phosphate but does not affect the lethal toxicity and the induction of Shwartzman reaction.

Biological activities of lipopolysaccharide-like substance (LLS) extracted from Leptospira interrogans serovar canicola strain Moulton

The biological activities of lipopolysaccharide-like substance (LLS) extracted from Leptospira interrogans serovar canicola strain Moulton by the hot phenol-water method were studied in mice. The addition of 12.5 micrograms/ml or more of LLS fraction increased the incorporation of [3H]thymidine into in vitro cultured spleen cells of C57BL/6 mice, while the activity of the LLS fraction was about 20 times weaker than that of Salmonella typhimurium lipopolysaccharide (LPS). Pretreatment of murine spleen cells with rabbit anti-mouse thymocyte antiserum did not diminish the mitogenic activity of leptospiral LLS, and the LLS could not increase the incorporation of [3H]thymidine into thymocytes, suggesting that LLS acts on a B-lymphocyte population of lymphocytes. When sheep erythrocytes and LLS fraction were injected intraperitoneally into BALB/c mice, LLS exhibited an enhancing effect on antibody response in vivo. However, lethal toxicity of the LLS fraction was about 500 times lower than that of LPS in C57BL/6 mice loaded with galactosamine. No antitumor activity of leptospiral LLS (250-1,000 micrograms/mouse) against the ascites form of Ehrlich carcinoma in ddY mice was observed. The biological activities of the LLS fraction from the organism were weaker than those of gram-negative bacterial LPS, suggesting that Leptospira possesses no typical LPS.

Effect of butyl 3-(1H-tetrazol-5-Yl) oxanilate (MTB) on immunological or non-immunological histamine and SRS(-A) release from guinea-pig, monkey and human lung tissue

We investigated the influence of butyl 3-(1H-tetrazol-5-yl) oxanilate (MTB) on the release of histamine and slow reacting substance of anaphylaxis (SRS-A) in vitro. MTB dose-dependently inhibited the release of not only histamine but also SRS-A from passively sensitized guinea-pig lung, while disodium cromoglycate (DSCG) hardly affected either release. MTB also resulted in a dose-dependent inhibition of the release of these mediators from the passively sensitized cynomolgus and rhesus monkey and that from human lung at concentrations similar to those inhibiting the release in the guinea-pig. Relatively lower inhibitory activities on the releases of both mediators from the cynomolgus monkey and human lung, but no effects on those from the rhesus monkey were observed with DSCG. MTB dose-dependently inhibited only SRS release from guinea-pig lung induced by phospholipase A2, although the compound did not show any inhibitory activity on the release of those from the calcium ionophore (A23187)-stimulated one. On the other hand, the release of SRS, but not that of histamine from the lung stimulated with A23187 as well as phospholipase A2 was inhibited by N-(3,4-dimethoxycinnamoyl)-anthranilic acid (tranilast, N-5'). From these results, MTB was a potent inhibitor of the anaphylactic release of the mediators, particularly SRS-A. It was suggested that the inhibitory mechanism of MTB is different from those of DSCG and N-5'.

Chemical properties of lipopolysaccharide-like substance (LLS) extracted from Leptospira interrogans serovar canicola strain Moulton

The aqueous layer was isolated from Leptospira interrogans serovar canicola strain Moulton by the hot phenol-water method. After ultracentrifugation, the precipitate was designated as lipopolysaccharide-like substance (LLS) fraction and the chemical composition was compared with that of bacterial LPS. The LLS fraction consists of 35.2% carbohydrate, 3.8% amino sugar, 36.4% lipid, 15.2% protein, and 0.3% phosphorus. Neutral sugars were detected as rhamnose, arabinose, xylose, 4-O-methylmannose, mannose, galactose, and a small amount of erythrose, fucose and glucose by gas-liquid chromatography (GLC), but 2-keto-3-deoxyoctonic acid was not detected in the LLS by thiobarbituric acid test and high voltage paper electrophoresis. Fatty acids detected by GLC were decanoic acid (C10: 0), dodecanoic acid (C12: 0), dodecenoic acid (C12: 1), tridecenoic acid (C13: 1), tetradecanoic acid (C14: 0), hexadecanoic acid (C16: 0), hexadecenoic acid (C16: 1), and octadecenoic acid (C18: 1). With SDS-polyacrylamide gel electrophoresis, bacterial LPS showed many orderly bands, while the banding pattern of the leptospiral LLS was very simple. These findings demonstrate that the physicochemical properties and chemical composition of LLS fraction from Leptospira are different from those of LPS extracted from gram-negative bacteria such as Enterobacteriaceae, and suggesting that Leptospira has no typical LPS.

[Immunopharmacological approach to the modulation of IgE antibody formation]

Soluble factors released by both T and B cells are involved in the class-specific regulation of IgE antibody formation; some factors have affinity for IgE, whereas others do not. The induction phase of the primary and secondary IgE antibody response is highly sensitive to treatment with such factors or some drugs. In contrast, persistent IgE antibody formation is mostly insensitive to the same treatments, indicating that this phase differs apparently from the induction phase. Thus, it is very important to note the marked differences between the regulatory mechanisms of these two phases when drugs responsible for the suppression of IgE antibody response are developed. In the present review, the recent advances pertaining to the regulation of IgE antibody formation in animals and humans are described in view of immunopharmacology.

Modulation of IgE synthesis by IgE-binding factors released by T cells of asthmatic patients with elevated serum IgE

The culture supernatants of unstimulated T cells (TCS) from asthmatic patients with elevated serum IgE were tested for IgE-binding factors (IgE-BFs) displaying the IgE-potentiating activity. The IgE-BFs were detected by their ability to inhibit the rosetting of RPMI 8866 cells with ox erythrocytes coupled with mouse monoclonal antibody (E-Mab) specific to Fc receptors for IgE (Fc epsilon R). TCS showing the rosette-inhibiting activity significantly enhanced the spontaneous IgE synthesis by B cells of allergic individuals. Interestingly, rosette-inhibiting factors could be removed by absorption with IgE-Sepharose from which they were subsequently eluated with acid buffer, indicating that the rosette inhibition was indeed mediated by IgE-BFs. In addition, such IgE-BFs had affinity for concanavalin A and lost their IgE-potentiating activity after treatment with trypsin and neuraminidase. In contrast, T cells treated with tunicamycin released IgE-suppressing factors capable of inhibiting the IgE-potentiating activity of TCS derived from untreated T cells. On the other hand, the culture supernatants from subpopulations depleted of Fc epsilon R+ T cells but not of Fc gamma R+ T cells contained neither rosette-inhibiting factors nor IgE-potentiating factors, suggesting that IgE-BFs were released by in vivo pre-activated Fc epsilon R+ T cells. With regard to circulating Fc epsilon R+ T cells determined by E-Mab, they were significantly higher in asthmatic patients with elevated serum IgE (0.77 +/- 0.15%) than in normal subjects (0.17 +/- 0.07%) in spite of a very small proportion of T cells bearing Fc epsilon R.

Enhancement of IgE synthesis and histamine release by T cell factors derived from atopic patients with bronchial asthma

Culture supernatants of unstimulated T cells (TCS) derived from normal donors or from atopic patients with bronchial asthma were tested for their ability to regulate the spontaneous IgE synthesis by B cells of normal and atopic subjects. The same TCS were also tested for their influence on the histamine release from leukocytes of house dust mites-sensitive patients. Addition of TCS to B cell cultures from allergic donors induced a dose-dependent increase of the spontaneous IgE production without affecting the synthesis of IgG, IgM, and IgA. The potentiating activity of TCS was observed only in B cell cultures spontaneously producing IgE; TCS were still active on irradiated B cells. The maximal IgE-enhancing activity was observed when TCS were added at the onset of B cell cultures. The supernatants of T cells lysed at day 0 did not contain IgE-potentiating factors. The antigen-induced but not the spontaneous histamine release from leukocytes of house dust mite-sensitive patients was enhanced by pretreatment with TCS from allergic donors. The enhancing activities of TCS on IgE synthesis and on histamine release could be removed by absorption with IgE-Sepharose and subsequently recovered by elution with glycine buffer. The results indicate that T cells of patients with asthma spontaneously release IgE-binding factors capable of increasing both the spontaneous IgE synthesis by B cells and the antigen-induced histamine release.

Allergic bronchopulmonary aspergillosis due to Aspergillus oryzae

A 19-year-old female student with allergic bronchopulmonary aspergillosis (ABPA) due to Aspergillus oryzae is reported. This organism was used for fermentation starter to make soybean paste in her father's workshop adjacent to the home where she lived. ABPA might be considered an occupational disease in certain situations.

Determination of ascorbic acid in human urine by high-performance liquid chromatography coupled with fluorimetry after post-column derivatization with benzamidine

High-performance liquid chromatography on two Asahipak GS-320 hydrophilic gel columns (50 X 0.76 cm I.D.), connected in series, with 0.015 M tartrate buffer (pH 3.0), containing 2 mM ethylenediaminetetraacetate and 0.05% beta-thiodiglycol as eluent allowed the separation of glucose, diketogulonic acid + diketogluconic acid, dehydroisoascorbic acid, dehydroascorbic acid, ascorbic acid, and isoascorbic acid within 55 min. Ascorbic acid in a urine sample was stabilized by the addition of an equal volume of 5% metaphosphoric acid solution, containing 0.5% of beta-thiodiglycol. Filtration of the mixture through a column of Dowex 50W-X8 (H+) facilitated the determination of ascorbic acid and isoascorbic acid in human urine. Samples could be analyzed every 20 min.

Immunopharmacological actions of an extract isolated from inflamed skin of rabbits inoculated with vaccinia virus (neurotropin); enhancing effect on delayed type hypersensitivity response through the induction of Lyt-1+2- T cells

To clarify the immunopharmacological action of an extract isolated from inflamed skin of rabbits inoculated with vaccinia virus (Neurotropin), its effect on delayed type hypersensitivity (DTH) response to sheep red blood cells (SRBC) in mice was examined. Neurotropin enhanced the DTH response in C57BL/6 mice which were low responders to SRBC, but not in either BALB/c or C3H/He mice (high responders) when administered i.p. for 4 consecutive days prior to sensitization. However, Neurotropin did not affect the formation of plaque-forming cells to SRBC in C57BL/6 mice under the condition where it enhanced the DTH response. We further examined the mechanism by which Neurotropin enhanced the DTH response in C57BL/6 mice by means of cell transfer experiments. Spleen cells from mice administered Neurotropin i.p. for 4 days, but not saline, could enhance the DTH response when transferred i.v. into normal syngeneic mice just before sensitization. However, the treatment of the spleen cells with anti-Thy-1.2 + complement (C) or with anti-Lyt-1.2 + C, but not with anti-Lyt-2.2 + C, abrogated its enhancing effect. The depletion of macrophages from the cells had no effect. On the other hand, the spleen cells from mice administered Neurotropin had no enhancing effect in the effector phase of DTH response, and they showed a helper T cell activity in a DTH helper T cell assay system in which cyclophosphamide-treated mice were used as recipients. These results suggest that Neurotropin enhances the DTH response in low responder mice through the induction of Lyt-1+2- DTH helper T cells.

Immunopharmacological actions of the new antiallergic drug 11-oxo-11H-pyrido[2,1-b]quinazoline-2-carboxylic acid. Effects on type I hypersensitivity reactions in human leukocytes and in human and monkey lungs

The effects of 11-oxo-11H-pyrido[2,1-b]-quinazoline-2-carboxylic acid (Sm 857), a new antiallergic drug, on histamine release from human leukocytes and from human and monkey lungs were investigated. Sm 857 dose-dependently inhibited histamine release induced by mite antigen, anti-human IgE, calcium ionophore A23187 (A23187) and protein A from peripheral leukocytes of atopic patients, but had no effect on the levels of cyclic AMP and GMP in human leukocytes. In addition, antigen- or anti-human IgE-induced anaphylactic histamine release from human and monkey lung fragments passively sensitized with human reaginic serum sensitive to mite antigen as well as A23187-induced histamine release from non-sensitized monkey lung fragments, were inhibited dose-dependently by Sm 857. However, no inhibition of spontaneous histamine release from human leukocytes or monkey lung fragments by Sm 857 was observed.

[Effect of interferon-alpha (MOR-22) on human NK cell activity]

We studied the effect of human lymphoblastoid interferon (IFN-alpha; MOR-22) on the natural killer (NK) cell activity of human peripheral blood lymphocytes (PBL). The NK cell activity of PBL from 12 healthy donors against K562 target cells was augmented by an average of 3.8 times by pretreatment with IFN 1,000 IU/ml for 2h. Augmentation was observed after pretreatment with IFN at a concentration of 10 IU/ml for 2 h or 1,000 IU/ml for 30 min. Augmented NK cell activity brought about by pretreatment with IFN showed a wide cytotoxic spectrum against human tumor cell lines. The sensitivities of the cell lines to NK cell activity were independent of the cell origin or antiproliferative effect of IFN. It was suggested that the NK cells activated by IFN might be a population expressing the Leu-11 positive marker because of nearly complete depletion of NK activity by pretreatment with anti-Leu-11b and complement. These results suggest that the activation of NK cells by IFN may play an important role in the antitumor effect of IFN.

[Study on human lymphoblastoid interferon-alpha (MOR-22): Part III. Antitumor effect on nude mouse-transplanted human tumors]

The effects of human lymphoblastoid interferon-alpha (MOR-22) on the growth of xenografted human tumors in nude mice were examined. IFN-alpha was administered subcutaneously to mice with renal tumor (ACHN), intratumorally for glioblastoma (U-373MG) or intravenously with uterine cervical tumor (HeLa S3). The dosages of IFN-alpha were 2 X 10(4)-5 X 10(5) IU/mouse for ACHN tumor, 1 X 10(5)-5 X 10(5) IU/mouse for U-373MG tumor and 3 X 10(4)-1 X 10(5) IU/mouse for HeLa S3 tumor. IFN-alpha inhibited the growth of these tumors in a dose-dependent manner.

[Antiproliferative activities of interferon-alpha]

The antiproliferative activities of human lymphoblastoid interferon-alpha (MOR-22) against 22 cultured human cell lines were examined. Daudi cells and ACHN cells were highly sensitive to interferon compared with other human cells. The cell lines derived from renal and brain tumors showed concentration-dependent growth inhibition as determined from a 7-day growth curve but the concentration dependency was different in various cell lines. It was shown that longer exposure to interferon was necessary to obtain antiproliferative activity, and cell growth inhibition was completely reversible by washing the cultures. It was suggested that interferon had a time-dependent antiproliferative action.

Estimation of catecholamines by ion-exchange chromatography on Asahipak ES-502C, using glycylglycine as the post-derivatizing agent

The estimation of catecholamines in human urine was carried out by ion-exchange chromatography on a column of a weakly acidic ion exchanger with an hydrophilic matrix. The catecholamines were first adsorbed onto Amberlite CG-50 (buffered at pH 6.5 with 0.4 M phosphate buffer) and selectively eluted by 0.66 M boric acid solution. They were then separated from impurities that responded to fluorometric detection by isocratic elution from a column of Asahipak ES-502C, a cross-linked vinyl alcohol copolymer with carboxymethyl groups, at 60 degrees C. The mobile phase was 0.05 M sodium succinate buffer pH 5.25 containing 0.015 M borate and 0.5 mM ethylenediaminetetraacetate. Isoproterenol was used as the internal standard; epinephrine, norepinephrine, isoproterenol and dopamine were eluted in this order. One sample could be analyzed every 35 min. The detection limits were 0.2 ng for epinephrine and norepinephrine, 0.6 ng for dopamine. The elution pattern was quite reproducible; the elution volumes of the catecholamines had not changed after 500 determinations.

Separation of ascorbic acid, dehydroascorbic acid, diketogulonic acid and glucose by isocratic elution from a column of a hydrophilic gel

High-performance liquid chromatography on an Asahipak GS-320 hydrophilic gel column with tartrate buffer (0.015 M, pH 3.0) containing 2 mM ethylenediaminetetraacetate and 0.05% beta-thiodiglycol as the eluent allowed the separation of glucose, diketogulonic acid, dehydroascorbic acid and ascorbic acid within 30 min. Fluorimetric monitoring of these compounds in the eluate with benzamidine at alkaline pH and at 90 degrees C in the presence of potassium sulphite allowed the determination of nanogram amounts of ascorbic acid, dehydroascorbic acid and diketogulonic acid. This method was applied to the determination of ascorbic acid in fruit juice.

Antitumor activity of Sphaerotilus natans and its slime fraction in mice

Antitumor activity of the whole cell and slime of an aquatic sheathed bacterium, Sphaerotilus natans IAM 12068, against ascites form of Ehrlich carcinoma in ddY mice was investigated. Intraperitoneal injection of whole cells and the slime fraction showed remarkable antitumor activity against mice inoculated with 10(4) to 10(5) tumor cells, the slime fraction being more effective. To examine the chemical nature of the active principle in the slime fraction, separation by Sepharose 4B gel filtration was carried out and two fractions designated as GF-P-1 and GF-P-2, which are mainly composed of protein, carbohydrate, and lipid, were obtained. GF-P-1 fraction, which contains large amounts of fucose and unidentified sugar as neutral sugar, showed marked antitumor activity at half the dose of the slime fraction, whereas the antitumor activity of GF-P-2, which is composed mainly of protein, was weak. This finding indicates that GF-P-1 fraction of S. natans slime may be a main active principle. The consistently demonstrable antitumor activity of GF-P-1 was abrogated by treatment of mice with silica, an anti-macrophage agent, suggesting that the antitumor activity of GF-P-1 depends on the activation of macrophages.

[Immunopharmacological actions of neurotropin (4). Effect of neurotropin on mouse peritoneal macrophages]

It was reported that neurotropin (NSP), an extract isolated from the inflamed skins of rabbits inoculated with vaccinia virus, activates murine T cell functions participating in cell-mediated immunity. The present study was undertaken to examine the effect of NSP on plastic dish-adherent macrophages (M phi) from ddY mice in vitro. Total activities of beta-glucuronidase and N-acetyl-beta-D-glucosaminidase in resident peritoneal M phi was slightly enhanced when the M phi were cultured with NSP (10-1000 micrograms/ml) for 48 and 96 hr, but no enhancement was noted in 24 hr culture. Intracellular activity of lactate dehydrogenase (LDH) was also strongly enhanced in a dose-dependent manner by culturing with NSP for 48 and 96 hr. The enhanced LDH activity in the M phi cultured with NSP for 96 hr was completely inhibited by cycloheximide, an inhibitor of protein synthesis. In addition, consumption of glucose in the culture media by the M phi was also enhanced by culturing with NSP for 96 hr. Intracellular activity of LDH and glucose consumption of plastic dish-nonadherent cells from normal mouse peritoneal cells, however, was not enhanced by NSP in 96 hr culture. In regard to allogeneic M phi-mediated cytostatic activity to P815-X2 mastocytoma, NSP had no effect on cytostatic activities of the resident and thioglycollate-induced M phi, although NSP by itself dose-dependently inhibited the growth of P815-X2 mastocytoma without affecting cell viability. These results suggest that NSP biochemically activates mouse peritoneal M phi in vitro, but the M phi activated by NSP can not inhibit the growth of P815-X2 mastocytoma.

Phospholipases of Leptospira. I. Presence of phospholipase A1 and lysophospholipase in Leptospira biflexa

The hydrolysis of phosphatidylethanolamine, phosphatidylcholine, lysophosphatidylcholine, and trioleoylglycerol by Leptospira biflexa strain Urawa was studied in vitro. Phospholipase A1 was identified by the formation of 32P- and 14C-labeled lysoderivatives from 32P-phosphatidylcholine, 32P-phosphatidylethanolamine, or 1-acyl-2-[1-14C]oleoyl-sn-glycero-3-phosphorylcholine. Phospholipase A1 activity was independent of lipase in the microorganism since 14C-labeled trioleoylglycerol was scarcely attacked under the same conditions in which the phospholipids were hydrolyzed. Lysophospholipase activity was also demonstrated using 32P- and non-labeled lysophosphatidylcholine. The activity of phospholipase A1 was found in a broad range of pH but no optimal pH was determined. The pH optimum of lysophospholipase was 8.0. Both enzymes were labile to heat. Phospholipase C activity, however, could not be detected because no radioactive di- and monoacylglycerol was found in the experiment with 1-acyl-2-[1-14C]-oleoyl-sn-glycero-3-phosphorylcholine as the substrate. It was inferred that phosphatidylethanolamine, which was the major component of phospholipids in leptospirae, was hydrolyzed serially by phospholipase A (A1 and/or A2?) and lysophospholipase to glycerophosphorylethanolamine via 2-acyl-type-lyso-derivative as one metabolic pathway of the substrate.

Chemical compositions of cell walls and polysaccharide fractions of spirochetes

Cellular polysaccharide fractions of various representative members of genera of the family Spirochaetaceae were obtained by the ammonium hydroxide extraction method. The sugar composition of the polysaccharide preparations was complex and many kinds of sugars such as rhamnose, fucose, ribose, xylose, mannose, galactose, and glucose were detected in all of the spirochetes tested. Of particular interest was the presence of 4-O-methylmannose as a constituent polysaccharide in members of the genus Leptospira. This sugar was not detected in the polysaccharides of Spirochaeta, Borrelia, and Treponema. The chemical compositions of cell wall fractions were also examined. 4-O-Methylmannose was detected in the cell wall polysaccharides of the genus Leptospira but not in cell walls prepared from the Spirochaeta, Borrelia, and Treponema. The diaminopimelic acid present in cell wall peptidoglycans of the genus Leptospira was meso-diaminopimelic acid (A2pm). The molar ratios of alanine, glutamic acid, A2pm, glycine, muramic acid, and glucosamine in leptospiral cell walls were found to be approximately 2:1:1:1:1:1. In contrast to the Leptospira, the peptidoglycans of genera Spirochaeta, Borrelia, and Treponema contained ornithine (Orn) but not A2pm. Since 4-O-methylmannose and A2pm were found in the cell wall fractions of genus Leptospira but not in Spirochaeta, Borrelia, or Treponema, it was suggested that the chemical compositions of the cell wall might become an important criterion for the chemotaxonomy of Spirochaetales.

Sugar synthesis in Leptospira. II. Presence of glyoxylate cycle enzymes

The presence and some properties of the key enzymes of the glyoxylate cycle, isocitrate lyase (threo-Ds-isocitrate glyoxylate-lyase, EC 4.1.3.1) and malate synthase (L-malate glyoxylate-lyase (CoA-acetylating) EC 4.1.3.2), were investigated in Leptospira biflexa. Isocitrate lyase activity was found for the first time in the organism. The enzyme was induced by ethanol but not by acetate. The optimum pH was 6.8. The activity was inhibited by phosphoenolpyruvate, a specific inhibitor of isocitrate lyase. The optimum pH of malate synthase of L. biflexa was about 8.5. The Km value for glyoxylate was 3.0 X 10(-3) M and the activity was inhibited by glycolate, the inhibitor. The results strongly suggested the presence of a glyoxylate cycle in Leptospira. The possibility that the glyoxylate cycle plays an essential role in the synthesis of sugars, amino acids and other cellular components as an anaplerotic pathway of the tricarboxylic acid cycle in Leptospira was discussed.