Shinpei Torii

16-Kilodalton Rice Protein Is One of the Major Allergens in Rice Grain Extract and Responsible for Cross-Allergenicity between Cereal Grains in the Poaceae Family

Cross-allergenicity between five cereal grains including rice, wheat, corn, Japanese millet (Panicum crus-galli L. var. frumentaceum Trin.) and Italian millet (Setaria italica Beauv. var. germanica schrad.) was examined by radioallergosorbent test (RAST) and RAST inhibition assay. There were significant close correlations between every combinations of RAST values for the five cereal grain extracts. RAST inhibition assay of each extract against RAST discs coupled with other cereal grain extracts indicated marked cross-reactivity of IgE binding between these cereal grain extracts. Rice protein 16KD (RP16KD) was shown to be one of major allergens in rice grain extracts by immunoblotting analysis, histamine release assay from human leukocytes and RAST inhibition. Next, the involvement of RP16KD in the cross-allergenicity between these cereals was investigated. RAST values for RP16KD significantly correlated with that for Italian millet as well as rice but not with those for corn and wheat. There was a trend of positive correlation between RAST values for RP16KD and Japanese millet. In the RAST inhibition assay using sera with positive RAST for these five cereal grain extracts and RP16KD, RP16KD inhibited IgE binding to these all cereal discs in a dose-dependent manner. Similarly, all of the five cereal grain extracts showed an effective decrease in IgE binding to the RP16KD disc. These results indicated possible participation of IgE binding structure on RP16KD in cross-allergenicity between these cereal grain extracts in the Poaceae family.

Detection of IgE antibody against Candida albicans enolase and its crossreactivity to Saccharomyces cerevisiae enolase

Candida albicans 46 kDa protein, a glycolytic enolase enzyme, is an important allergen of the yeast. The purpose of the study was to detect circulating IgE and IgG antibodies against C. albicans enolase (CAE). We isolated CAE using sequential DEAE Sephacel and Pl 1 column chromatography from spheroptasts of C. albicans, and delected IgE and IgG antibody against CAE by immunoblotting. Crossreactivity of enolose of C. albicans and Saccharomyces cerevisiae was also examined by immunoblotting and immunoblot inhibition test. Among 54 sera with positive IgE RAST to C. albicans, IgE antibody against CAE was detected in 20 sera (37%) and IgG antibody in 27 sera (50%). The allergenic potency of CAE was confirmed using a skin‐prick test in three patients. Simultaneous IgE binding to S. cerevisiae enolase was only observed in four out of 20 sera reacting to CAE. Pre‐treatment of sera with CAE completely inhibited IgE binding to S. cerevisiae enolase. Whereas the latter only partially inhibited IgE binding to CAE. These results suggest that CAE shares some crossreacting epitopes with S. cerevisiae enolase, representing minor components of CAE but dominant segments of S. cerevisiae enolase.

Effect of dietary α-linolenate/linoleate balance on leukotriene production and histamine release in rats

Rats were fed semi-purified diets supplemented either with safflower seed oil rich in linoleate (18:2n-6) or with perilla seed oil rich in α-linolenate (18:3n-3) through two generations. In the major phospholipids of polymorphonuclear leukocytes (PMNs), the proportions of n-6 polyunsaturated fatty acids (18:2, 20:4, 22:4 and 22:5) were higher but those of n-3 acids (20:5, 22:5 and 22:6) were lower in the safflower group than in the perilla group. When stimulated with a calcium ionophore, the PMNs from the safflower group produced 27 % more leukotriene (LT) B4 than those from the perilla group. The formation of LTB5 which has biological activities less than 110 those of LTB4, was negligible in the safflower group but was 40 ng/107 PMN cells in the perilla group. The amount of the total LTB formed in the perilla group tended to be more than in the safflower group. The formation of SRS-A (slow-reacting substances of anaphylaxis) by PMNs was determined by measuring the spasmogenic activities of LTs on guinea pig ileum. SRS-A activity was 59 % higher in the safflower group than in the perilla group. In contrast, histamine release from rat peritoneal mast cells was not significantly different between the two groups. Thus, the increasing the α-linolenate/ linoleate ratio of diets results in the decreased formation of LTs derived from 20:4n-6 in PMNs. This may be beneficial in lowering the severity of allergic and inflammatory responses caused by LTs, and thereby shifting the pathological symptoms to normal self-defense mechanism.

Role of tachykinin and bradykinin receptors and mast cells in gaseous formaldehyde-induced airway microvascular leakage in rats

We have investigated the effects of CP-99,994 [(+)-(2s,3s)-3-(2-methoxybenzylamino)-2-phenylpiperidine], a tachykinin NK1 receptor antagonist, HOE 140 (D-Arg[Hyp3,Thi5,D-Tic7,Oic8]bradykinin), a bradykinin B2 receptor antagonist, and ketotifen (4-(1-methyl-4-piperidylidene)4 H-benzo[4,5]cycloheptal[1,2-b]thiophen-10(9H)-one hydrogen fumarate), a histamine H1 receptor antagonist with mast cell-stabilizing properties, on microvascular leakage induced by gaseous formaldehyde. Extravasation of Evans blue dye into airway tissues was used as an index of airway microvascular leakage. Leakage of dye in the trachea and main bronchi increased significantly in a concentration-dependent fashion after 10 min inhalation of formaldehyde (5-45 parts per million (ppm)). The airway response induced by 10 min inhalation of 15 ppm formaldehyde (trachea: 119.5 +/- 13.9 ng/mg, n = 7; main bronchi: 139.6 +/- 7.9 ng/mg, n = 7) was abolished by the administration of CP-99,994 (3 and 6 mg/kg i.v.), but not by the administration of HOE 140 (0.65 mg/kg i.v.) nor ketotifen (1 mg/kg i.v.). The increase in vascular permeability induced by formaldehyde in the rat airway was mediated predominantly by NK1 receptor stimulation. Activation of bradykinin receptors and mast cells did not appear to play an important role in this airway response.

Necrotizing toxoplasmic encephalitis in a child with the X-linked hyper-IgM syndrome

Abstract We report on a 9-year-old boy with the hyper-IgM syndrome who presented with rapid impairment of consciousness. The brain CT scan showed multiple round lucencies, and the brain histology revealed necrotizing toxoplasmic encephalitis. This patient, whose CD40/CD40 ligand system was impaired, indicates the importance of this system for defence against toxoplasmic infection. Conclusion Although disseminated toxoplasmosis is a rare complication of the hyper-IgM syndrome, it must be included in the differential diagnosis of infections.

Clonal haematopoiesis in children with acquired aplastic anaemia

Summary. The methylation pattern of three X‐linked genes, phosphoglycerate kinase (PGK), hypoxanthine phosphoribosyl transferase (HPRT) and DXS255 detected by hypervariable M27β probe, was analysed to determine the proportion of aplastic anaemia (AA) with clonal haematopoiesis in Japanese children. Methylation analysis was performed on DNA from separated granulocytes and compared to that of bone marrow derived fibroblasts to exclude selective lyonization in all somatic cells. Of 20 female patients examined, the methylation pattern of at least one gene was informative in granulocyte DNA from 18 patients (90%). Of these, 8/20 patients (40%) were heterozygous for PGK, 8/18 (44%) were heterozygous for HPRT and 17/18 (94%) were heterozygous for DXS255. In 14/18 patients both alleles were equally methylated. Four patients exhibited a unilateral methylation pattern in their granulocytes. The same unilateral pattern was again demonstrated in fibroblasts from two of the four patients suggesting that in the latter one X chromosome was selectively inactivated in all of the somatic cells. The remaining two patients showed a unilateral methylation pattern that was restricted to their granulocytes, suggesting the existence of true clonal haematopoiesis. They responded well to antilymphocyte globulin (ALG) and presently have no evidence of a clonal disorder such as myelodysplastic syndrome (MDS) or paroxysmal nocturnal haemoglobinuria (PNH). Although these results indicate that some children with AA exhibit clonal haematopoiesis, analysis of a greater number of subjects will be required to establish the clinical value of clonal haematopoiesis in patients with AA.

The prevalence of IgE sensitization to formaldehyde in asthmatic children

Background:  Formaldehyde (FA) is well documented as a cause of occupational asthma. Recently, attention has been paid to FA as an allergen and a pollutant that enhances allergic sensitization. We have investigated the prevalence of FA‐specific IgE in asthmatic children and the correlation between IgE sensitization to FA and the severity of asthma.

Modulation of eosinophil chemotactic activities to leukotriene B4 by n-3 polyunsaturated fatty acids

Eosinophil accumulation induced by leukotriene B4 appears to be involved in the pathogenesis of allergic diseases. We evaluated the effects of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) on chemotaxis to leukotriene B4 in guinea pig peritoneal eosinophils. Guinea pigs that were sensitized to polymyxin B were administered an intraperitoneal injection of polymyxin B (1 mg/animal) alone or combined with DHA (15 or 50 mg/kg, i.p.), EPA (50 or 100 mg/kg, i.p.), or with linoleic acid (LA) (100 mg/kg, i.p.). Forty hours later, eosinophils were obtained from the intraperitoneal lavage fluid and purified. The chemotactic and chemokinetic responses of eosinophils to leukotriene B4 were measured using a 96-well microchemotaxis chamber. DHA significantly decreased the chemotactic and chemokinetic responses of eosinophils in a dose-dependent fashion. A higher dose of EPA also significantly inhibited both of those responses, whereas LA had no effect. Our results suggested a possible mechanism for the improvement of allergic diseases by dietary supplementation with n-3 PUFA.

A case retaining contact urticaria against egg white after gaining tolerance to ingestion

A girl, 5.7 years old, gained tolerance to egg white ingestion in spite of high immunoglobulin E (IgE) antibody titers to egg white but retained contact urticaria against egg white. She developed atopic dermatitis on her face at 2 months of age and showed high IgE antibody titers to egg white and cows milk. Accidental ingestion of egg products initiated immediate symptoms such as wheezing, urticaria, erythema and edema of the eyelids and conjunctiva three times. These symptoms were confirmed by challenge tests using boiled egg white at 3.9 years of age. She also reacted positively to a 20 min patch test on her volar arm with raw egg white. However, there were no reactions to the oral challenge test by boiled egg and freeze‐dried egg white at 5.1 and 5.7 years of age, respectively. This non‐responsiveness was confirmed by a double‐blind, placebo‐controlled food challenge using freeze‐dried egg white. Nevertheless, she showed positive reactions to a 20 min patch test with freeze‐dried egg white. Her IgE antibody titers to the egg white components including ovomucoid, ovalbumin, ovotransferrin and lysozyme as well as egg white were high from 2.9 to 5.7 years old. Her IgE antibody titers for the ovomucoid fragments digested by pepsin, chymotrypsin and trypsin were not lower than those of positive control subjects. The binding activity of IgE antibody to ovomucoid, however, decreased from 2.9 to 5.6 years as shown by radioallergosorbent test (RAST) inhibition assays. The IgE antibody showed weaker binding activity to pepsin‐ and chymotrypsin‐digested ovomucoid that were filtered through cut‐off 10 000 filter at the age of 2.1 and 5.7 years. We speculated that the maturation of secretion of digestive enzymes was involved in the mechanisms of the acquisition of tolerance to egg white ingestion in spite of the persistence of contact urticaria.

Production of granulomatous inflammation in lungs of rat pups and adults by Sephadex beads.

Granulomatous inflammation is a process that involves mononuclear leukocytes as well as other inflammatory cells. The heterogeneity of its appearance may be due to the variety of cytokines and chemokines that are involved. In this study, we compared granuloma formation and bronchoalveolar leukocyte differential in the lungs of rats (2- and 8-wk-old) that were treated intravenously with Sephadex beads. In addition, the kinetics of cytokine and chemokine production was determined in these groups. In adults, the beads caused lung granulomas associated with infiltration of eosinophils and neutrophils and increased eosinophil and neutrophil counts in the bronchoalveolar lavage fluid within 16 h. In pups, the granulomas were formed slowly and did not reach the size achieved in adults. Eosinophils and neutrophils were sparsely found in the periphery of the granulomas, even at 32 h. Pups were also unable to respond rapidly to Sephadex bead treatment with eosinophil and neutrophil infiltration in the bronchoalveolar lavage fluid. Tumor necrosis factor-α was significantly increased in both groups, but the cytokine was lower in pups than in adults. Interferon-γ and eotaxin were increased only in adults, and IL-4 and regulated on activation, normal T cell expressed, and secreted was increased only in pups. In conclusion, the i.v. administration of Sephadex beads produced granulomatous inflammation in the lungs of adult rats, but pups were unable to respond as rapidly to the treatment. In addition, the difference in response between the two age groups was associated with the kinetics of cytokine and chemokine production.