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M Suko

Publications and source records attributed to M Suko.

At least 55 records · Page 3Linked to original sources

Food-dependent, exercise-induced anaphylaxis: a study on 11 Japanese cases.

Eleven patients with food-dependent, exercise-induced anaphylaxis were studied. Seven patients experienced anaphylactic symptoms only after eating certain foods, such as shellfish, wheat, and grape before exercise. In the remaining four patients, no specific food could be identified, but the act of eating itself predisposed to anaphylaxis. Their anaphylactic symptoms were all clearly distinguished from cholinergic urticaria by history. Patients who developed anaphylactic symptoms before 20 years of age (N = 7) were atopic themselves or had atopic first-degree relatives. Six patients had increased serum IgE levels, and IgE antibodies against the causative food allergens were detected by the skin prick test or RAST in four cases. In contrast, patients who developed the symptoms after 30 years of age (N = 4) appeared to have a less atopic background, and IgE levels were within normal range except in one case. Three of four patients in the latter group developed symptoms after ingesting food made of wheat followed by exercise. All patients were sensitive to wheat as determined by the skin prick test. In six of 11 patients, a considerable rise in plasma histamine concentration was observed after exercise challenge with treadmill alone, and food intake followed by exercise induced a further increase in one patient.

Adolescent↗

T-cell-dependent accumulation of eosinophils in the lung and its inhibition by monoclonal anti-interleukin-5.

The transnasal administration of an extract of the parasite Ascaris suum to C57BL/6 mice for 3 weeks produced marked eosinophilia in the bronchoalveolar lavage (BAL) fluid. The oral administration of ciclosporin significantly suppressed the pulmonary eosinophilia. Athymic C57BL/6-nu/nu mice failed to develop pulmonary eosinophilia. These data indicate that the pulmonary eosinophilia caused by this parasite extract is T-cell-dependent. Genetically mast-cell-deficient (WB x C57BL/6) F1-W/Wv (W/Wv) mice developed marked eosinophilia in the BAL, which shows that mast cells are not necessary in the formation of lung eosinophilia in this model. Monoclonal antimurine interleukin-5 injected intraperitoneally clearly inhibited the infiltration of eosinophils in the lung, suggesting that T-cell-derived interleukin-5 is essential.

Animals↗

Interleukin-4 gene expression and IgE responsiveness.

Interleukin-4 (IL-4) gene expression by stimulation with concanavalin A (Con A) in murine spleen cells was examined. The amount of IL-4 mRNA induced by Con A was greatest in spleen cells obtained from IgE high responder strains of mice. A trace amount of IL-4 mRNA was induced in spleen cells from IgE low responder (SJL) mice. The amount of IL-4 mRNA induced in spleen cells from an IgE intermediate responder (C57BL/6) was smaller than that from high responders, but significantly greater than that from low responders. Spleen cells from IgE nonresponders (SJA/9) developed only a negligible amount of IL-4 mRNA. IL-4 mRNA was detected in human peripheral blood mononuclear cells (PBMC) stimulated with Con A. The IL-4 gene expression seemed to be greater in PBMC obtained from highly atopic patients and was decreased in PBMC from individuals showing hypo-IgE immunoglobulinemia (less than 10 IU/ml). The results obtained in the present study may indicate that high and low IgE responder traits are determined depending on their levels of IL-4 mRNA expression.

Animals↗

Inhibition of allergen-induced bronchoconstriction in sensitized guinea pigs by orally administered allergen.

Crude mite extract (CME) was orally administered to guinea pigs sensitized to CME. It was shown that such treatment reduces the bronchoconstrictive response upon allergen provocation. Isolated tracheae taken from guinea pigs orally administered CME allergen showed less contraction in response to CME as compared to those obtained from sensitized but not orally treated animals. The oral administration of allergens seemed to attenuate the bronchial hyperresponsiveness of sensitized animals to a non-specific chemical stimulus (histamine). IgE antibodies titrated by 8 days passive cutaneous anaphylaxis, and IgG1 and IgG2 antibodies measured by ELISA were comparable in the sera obtained from animals before and after CME treatment.

Administration, Oral↗

Synthesis of biologically active recombinant Der f II.

A cDNA library corresponding to mite protein was screened employing anti-Der f II antibody. Two possible clones containing plasmids pFL1 and pFL11 were obtained. The two plasmids had insertions of about 500 basepairs. The DNA sequences of the two insertions were determined, from which the amino acid sequences were deduced. The amino acid sequence of the purified native Der f II protein could be determined to 45 residues from the N terminus. As a result of comparison, we concluded that the cDNAs prepared from live Dermatophagoides farinae mite corresponded to the mite allergen Der f II. The recombinant Der f II was biologically active.

Allergens↗

Interleukin-4 gene expression in human peripheral blood mononuclear cells.

Interleukin-4 (IL-4) mRNA was detected in normal human peripheral blood mononuclear cells (PBMC) stimulated with concanavalin A by Northern blot analysis. The signal was undetectable in PBMC before the stimulation, but became detectable 3 hrs after the stimulation and reached a maximum in 3-6 h and disappeared gradually thereafter. Immunosuppressive drugs such as ciclosporin, hydrocortisone and prednisolone inhibited the IL-4 mRNA expression dose dependently. Interferon-gamma did not show any inhibitory effect on IL-4 gene expression.

Blotting, Northern↗

Cloning and expression of cDNA coding for the major house dust mite allergen Der f II in Escherichia coli.

A cDNA library corresponding to mite protein was screened using anti-Der f II, a major allergen from the house dust mite Dermatophagoides farinae, antibody. Three possible clones were obtained that contained cDNA fragments coding for Der f II, and the nucleotide sequences of the fragments were determined. There were minor differences observed affecting the deduced amino acid sequence among the three cDNA fragments. The amino acid sequence of the purified native Der f II protein could be analyzed to 45 residues from the N-terminus. As a result of comparison, all the three cDNA fragments code for a mature protein with a derived molecular weight of about 14,000. The amino acid sequence was not homologous to any known protein sequences and it contained six cysteine residues and no N-glycosylation sites.

Allergens↗

[Histamine release test of patients allergic to the house dust mite, Dermatophagoides farinae--analysis according to various clinical backgrounds].

Since the histamine release test is more complicated than some of the other tests, there are smaller number of clinical studies employing this method. In this study, we selected 25 males and 20 females, allergic to the house dust mite, to undergo the histamine release test challenged by 7 serial concentrations of the mite allergen diluted from 10 times to 10 million times the original allergen at a concentration of 0.01%. Histamine release was expressed as a percentage of the total histamine concentration contained in the cells. Allergen induced dose response curve of histamine release was drawn for each patient, and in order to characterize each curve, 5 different indices were selected and were averaged according to the clinical backgrounds of the patients. Significant increases in histamine release were observed in males under 25 and females above 26 years of age. Histamine release rate in patients with RAST score of above 3+ was significantly more enhanced than in those with RAST score of below 2+, though this result was significant only for those under 25 years of age. Blood samples taken in June-August, and September-November, showed significant increases in the histamine release, though the indices for enhancement differed in both seasons. When analyzed according to the numbers of years the patient was desensitized, the results showed, contrary to our expectations, a more increased release in the desensitized group than in the non-desensitized group.

Adolescent↗

The effect of platelet-activating factor on [14C]aminopyrine uptake by isolated guinea pig parietal cells.

C16- and C18- platelet-activating factor (PAF) at 10(-6) M enhanced the uptake of [14C]aminopyrine (AP) by isolated guinea pig parietal cells. This increase was inhibited by a PAF antagonist CV-6209. In a medium with a low calcium (Ca2+) concentration (2 uM), this increase was not observed, which indicates that the increase of AP uptake by PAF is dependent on extracellular Ca2+. PAF and lyso-PAF showed no effect on AP uptake in the presence of histamine or carbachol.

Aminopyrine↗

Bronchial responsiveness to mite allergen in atopic dermatitis without asthma.

Eight patients with atopic dermatitis (AD) without a history of asthmatic episodes and 8 patients with mite-allergic bronchial asthma (BA) were subjected to bronchial inhalation challenge with a nonspecific stimulus (acetylcholine) and an immunologically specific stimulus (house dust mite allergen). AD patients had a significantly greater concentration of IgE (p less than 0.01) and antimite IgE antibody (p less than 0.05) than BA patients. Nonspecific bronchial hyperreactivities of AD patients distributed from normal to asthmatic range. After allergen challenge, all 8 AD patients and all 8 BA patients showed an immediate asthmatic response (IAR). The mite extract concentration to induce an IAR was significantly (p less than 0.01) greater in AD patients than in BA patients. A late asthmatic response was observed in 6 out of 8 BA patients, whereas it was not observed in any AD patient. Our results showed that AD patients are less reactive to a specific mite allergen than BA patients in spite of greater concentrations of antimite IgE antibody. They suggest that this difference in the bronchial reactivity to the allergen concerns the difference in the onset of clinical symptoms and that a certain level of bronchial hyperreactivity to the allergen is a prerequisite for the development of asthmatic symptoms.

Adolescent↗

Interleukin-4 gene expression in high and low IgE responder mice.

Interleukin-4 (IL-4) gene expression in murine spleen cells was examined by stimulation with concanavalin A (Con A). Spleen cells from a DBA/2 strain of mice, a high IgE responder, expressed IL-4 mRNA within 3 h after incubation with Con A. Maximal IL-4 mRNA expression was observed 6-9 h after stimulation. The amount of IL-4 mRNA induced by Con A was greatest in spleen cells obtained from high IgE responder strains of mice. A trace amount of mRNA was induced in spleen cells from low IgE responder (SJL) mice. The amount of mRNA induced in spleen cells from an intermediate IgE responder (C57BL/6) was smaller than that from high responders, but significantly greater than that from low responders. Spleen cells from IgE nonresponders (SJA/9) developed only a negligible amount of IL-4 mRNA after stimulation with Con A. Time course and optimal concentration of Con A for the expression of IL-4 mRNA were essentially the same in high (DBA/2) and low (SJL) responder strains of mice. The decreased expression of IL-4 mRNA in low IgE responder spleen cells upon stimulation was not due to the decrease in Thy-1-positive cells or L3T4-positive cells in the spleen. The results obtained in the present study may indicate that high and low IgE responder traits are determined depending on their levels of IL-4 mRNA expression.

Animals↗

Experimental pulmonary eosinophilia in mice by Ascaris suum extract.

The transnasal administration of an extract of the parasite Ascaris suum (Asc) to C57BL/6 mice for 3 wk produced marked eosinophilia in the bronchoalveolar lavage (BAL) fluid. This pulmonary eosinophilia was not accompanied by blood eosinophilia. The oral administration of cyclosporin, 50 mg/kg body weight, every other day significantly suppressed the pulmonary eosinophilia. Athymic C57BL/6-nu/nu mice failed to develop pulmonary eosinophilia. These data indicate that pulmonary eosinophilia caused by this parasite extract is T-cell-dependent. Genetically mast-cell-deficient (WB X C57BL/6)F1-W/WV (W/WV) mice developed marked eosinophilia in the BAL, which shows that mast cells are not necessary in the formation of eosinophilia in BAL in this model. C57BL/6, W/WV, and Balb-C mice that developed eosinophilia in the BAL also showed elevated total IgE levels and IgE titers against Asc in the sera. On the other hand, C57BL/6-nu/nu mice and IgE low-responder SJL mice, which developed little eosinophilia, did not show elevated total IgE levels and IgE titers against Asc in the sera. However, oral administration of cyclosporin, 50 mg/kg, which inhibited eosinophilia in the BAL in C57BL/6 mice, did not significantly inhibit the elevation of total IgE or IgE against Asc in the sera. This indicates that serum IgE production is not required for the formation of eosinophilia.

Animals↗

Cigarette smoking induces formation of 8-hydroxydeoxyguanosine, one of the oxidative DNA damages in human peripheral leukocytes.

Active oxygen species (AOS) such as O2- and H2O2 have been shown to be generated from both gas and tar phases of cigarette smoke and it has been suggested that they are involved in carcinogenesis due to cigarette smoking. Therefore, we investigated the effect of cigarette smoking on oxidative DNA damages in human peripheral blood cells using 8-hydroxydeoxy-guanosine (8-OH-dG) as a marker. From ten healthy male volunteers aged 20-22 years, 5 ml of blood was taken before and 10 minutes after smoking 2 cigarettes in 10 minutes. After lysis of blood cell membranes leukocyte DNA was isolated using a DNA extractor and 8-OH-dG levels were determined using high performance liquid chromatography (HPLC) with electrochemical detection. The mean levels of 8-OH-dG increased significantly (P less than 0.05) from 3.3 +/- 0.8/10(6) dG (mean +/- SD) to 5.1 +/- 2.5 after smoking. These results indicate that cigarette smoking induces oxidative DNA damage in peripheral blood cells in a relatively short time.

8-Hydroxy-2'-Deoxyguanosine↗

[Procoagulant activity of alveolar macrophages in bleomycin-induced lung fibrosis in rats].

Interstitial and intraalveolar fibrin deposition is a prominent feature in adult respiratory distress syndrome and is also observed in the inflammatory phase of interstitial lung disease (ILD). It is suggested that the coagulation abnormality in these disorders may be implicated in the pathogenesis of subsequent fibrosis of the lung. In this study, we examined the procoagulant activity (PCA) of alveolar macrophages during the development of bleomycin-induced lung fibrosis in rats. The PCA of alveolar macrophages was significantly increased at 2, 7 and 14 days after the intratracheal administration of bleomycin compared with that of control rats. The greatest PCA was observed at 7 days after the bleomycin injection, the inflammatory phase in the development of lung fibrosis. Increased PCA returned to the normal value at 21 days, while the fibrotic process advanced and the collagen content increased in the lung. Alveolar macrophages at 7 days after the administration of bleomycin or saline were separated into five density fractions on discontinuous Percoll gradients. The increase in the percentage of low-density macrophages was observed in bleomycin-injected rats. The greatest PCA was demonstrated in the lowest-density fraction (specific gravity less than 1.030), while reduced activities were observed in the higher-density fractions, in each group. The increased PCA of alveolar macrophages during lung injury was due in part to the increase of low-density subpopulation, which had greater PCA, although the fibrin deposition in the development of lung fibrosis remained to be defined, the increase of coagulation pathways may contribute to the progression of interstitial fibrotic lung diseases.

Animals↗

[3 cases of food-dependent exercise-induced anaphylaxis in which aspirin intake exacerbated anaphylactic symptoms].

Exercise-induced anaphylaxis (EIAn) is a distinct form of physical allergy. As one of the predisposing factors of EIAn, food intake is often cited, and such cases are classified as food-dependent EIAn. Another factor reported is the administration of drugs. Recently we had 3 patients with food-dependent EIAn who showed more severe symptoms when they took aspirin orally. None of them had shown symptoms when they took aspirin alone. Symptoms were provoked only when they took aspirin for common cold, headache or toothache followed by certain foods and exercise. Two out of the 3 patients had experienced food-dependent EIAn before. However, after taking aspirin, their anaphylactic symptoms were more severe with more slight degree of exercise. Results of exercise challenge by treadmill showed that exercise alone induced an increase in plasma histamine concentrations in 2 out of the 3 patients 5 to 15 minutes after the challenge. These data suggest the possibility that our patients have an increased histamine releasability from mast cells responding to exercise, and that aspirin intake might enhance the process.

Adult↗

[Bronchial responsiveness to methacholine in the mouse tested by a new apparatus measuring respiratory resistance].

We developed a new apparatus for the measurement of mouse respiratory resistance (Rrs) by an oscillation method. Bronchial responsiveness to methacholine was studied in mice sensitized or not with egg albumin using this apparatus. All of the sensitized mice showed clearly increased bronchial reactivity upon nasal challenge with methacholine compared to normal control mice. The lung obtained from a sensitized mouse showed remarkable contraction of the bronchial smooth muscle, submucosal edema and cell infiltration around the bronchi. These results indicate that mouse Rrs is successfully measured by our newly developed apparatus and suggested that repeated sensitization of mice with allergen render their airway hyperreactive to methacholine.

Animals↗

Cloning and sequencing of cDNAs corresponding to mite major allergen Der f II.

A cDNA library corresponding to mite protein was screened employing anti-Der f II antibody. Two possible clones were obtained, which contained plasmids, pFL1 and pFL11, respectively. Both plasmids had insertions of about 500 base pairs. The DNA sequences of the two insertions were determined, from which the amino acid sequences were deduced. The amino acid sequence of the purified native Der f II protein could be determined to 45 residues from the N-terminus. As a result of comparison, we concluded that the cDNAs prepared from live mite Dermatophagoides farinae corresponded to the mite allergen, Der f II.

Allergens↗