Lipocalin-type prostaglandin D synthase and egg white cystatin react with IgE antibodies from children with egg allergy.

BACKGROUND: Ovalbumin, ovomucoid, ovotransferrin, lysozyme, and ovomucin are known to be major allergens found in egg white. Egg white protein is composed of over 30 proteins; many of which have neither been identified nor their allergenicities characterized. This study set out to analyze whether unknown proteins that bind to IgE antibodies in serum from patients with egg allergy exist in egg white. METHODS: Diluted egg white proteins were separated by 2-dimensional (2-D) gel electrophoresis. Immunolabeling was performed on individual patient sera from 19 child patients with egg white allergy and 11 negative control subjects. Spots of egg white proteins that bound to the patients' IgE were identified by mass spectrometry-based proteomics. RESULTS: Egg white proteins were separated into 63 spots. Twenty-five of the 63 reacted with egg allergy patients' sera, and 10 of the 25 reactive spots showed IgE-reactivity to controls as well. Specific bindings to the IgE from egg allergy patients were found in 15 spots; one of which was confirmed as ovotransferrin. Among the other 14 protein spots, egg white cystatin and lipocalin-type prostaglandin D synthase (L-PGDS) were newly identified proteins that reacted with IgE in patients with egg allergy. CONCLUSIONS: We demonstrated that L-PGDS and cystatin reacted with serum IgE in patients with egg allergy. Our proteomics-based analysis in egg white gives a comprehensive map of proteins bound with IgE and should assist in enabling more accurate diagnoses and recommendations of desensitizing treatments for individual patients.

Relationship between the benefits of suplatast tosilate, a Th2 cytokine inhibitor, and gene polymorphisms in children with bronchial asthma.

Although currently available antiasthmatic drugs are effective for many patients with bronchial asthma, some patients do not respond well to medications or exhibit more frequent adverse effects compared to other patients. Antiasthmatic treatment should be tailored individually according to the predispositions and pathophysiological conditions of patients. No reports have been made concerning the relationships between the effects of Th2 cytokine inhibitors and gene polymorphisms. The present study was therefore performed to investigate the relationships between gene polymorphisms known to be involved in allergy and cytokine production in peripheral blood mononuclear cells and the clinical efficacy of suplatast tosilate, a Th2 cytokine inhibitor, to clarify factors determining responses to treatment. A total of 20 children were enrolled in the study. The children were enrolled in a run-in period of 2 weeks and then received suplatast tosilate orally for 8 weeks. The children or their parents were instructed to keep an asthma diary to record changes in signs/symptoms of bronchial asthma before and after treatment. Concentrations of interferon (IFN)-γ and interleukin (IL)-4 in the supernatant were determined using ELISA methods. Using the invader assay method, the genotypes of polymorphisms of the genes were determined. Treatment with suplatast tosilate was more effective in children without the -444 A/C polymorphism of the LTC4 synthase gene and in children without the IL-13 variant R110Q. In children who responded well, production of IFN-γ was significantly increased after treatment. In this study, responses to suplatast tosilate were associated with SNPs of the LTC4 synthase and IL-13 gene as well as change in the production of IFN-γ before and after drug administration.

The response of bovine beta-lactoglobulin-specific T-cell clones to single amino acid substitution of T-cell core epitope.

Cow's milk is one of the most common food allergens in the first year of life, with approximately 2.5% of infants experiencing an allergic reaction to it. Beta-lactoglobulin (BLG) is one of the major allergens in cow's milk. Previously, we reported that four of six T-cell clones (TCC) which were established from cow's milk allergy patients recognized BLGp97-117 as the core sequence and also recognized BLG in association with the human leucocyte antigen (HLA)-DRB1*0405 allele. Using two of these four TCCs, we evaluated the T-cell response to BLG peptides with single amino acid substitution or deletion and identified BLGp102-112 as the minimum essential region in BLGp97-117. In the alanine-scan assay, the proliferative responses of TCCs to pE108A disappeared, and the proliferative responses of TCCs to pC106A decreased. In the analog peptide proliferation assay, pY102S had retained some T-cell response to the two TCCs. Collecting these results, we propose a motif for the interaction between the HLA-DRB1*0405 allele and antigen peptide, and suggest that BLGp105-108 are important residues to retain the TCR/BLG-peptide/HLA complex. pY102A and pY102S are partial agonists for the T-cell receptor. These peptides might be considered as candidate peptides for the modification of the T-cell response to BLG in cow's milk allergy.

Lymphocyte Responses to Chymotrypsin- or Trypsin V-Digested beta-Lactoglobulin in Patients with Cow's Milk Allergy.

: Chymotrypsin- or trypsin V- (a mixture of trypsin and chymotrypsin) digested beta-lactoglobulin (BLG) peptides were prepared and were confirmed to have much less immunoglobulin (lg)G and lgE reactivity compared with intact BLG by IgG inhibition enzymelinked immunosorbent assay and IgE dot blotting. The lymphocyte responses to intact BLG and these peptides were examined using peripheral blood mononuclear cells (PBMCs) from 10 patients with cow's milk allergy. The PBMCs from most patients had lower lymphocyte responses to chymotrypsin- and trypsin V-digested BLG peptides than those to intact BLG. However, PBMCs from one and two patients retained significant proliferative responses to both peptides and to only the former peptide, respectively. Interferon-c production stimulated by chymotrypsin-digested peptides was still detectable in all five patients tested. Chymotrypsindigested BLG reduced lgE reactivity but still induced some lymphocyte responses.

A novel single-nucleotide substitution, Glu 4 Lys, in the leukotriene C4 synthase gene associated with allergic diseases.

Cysteinyl leukotrienes (cysLTs) play important roles in bronchial asthma, and can mediate bronchial smooth muscle constriction and increase mucous secretion, vascular permeability and cellular infiltration. We identified a novel heterozygous single-nucleotide substitution 10G>A (Glu 4 Lys) in the first exon of the leukotriene C4 synthase gene (LTC4S). This substitution was detected in 5 of 141 allergic patients, but not in 110 nonallergic subjects. There was a difference in the Glu 4 Lys frequency between the allergic patients and nonallergic subjects (Fisher's exact test, p=0.0460). The five patients with Glu 4 Lys had allergic diseases such as bronchial asthma and/or allergic dermatitis. Furthermore, a familial analysis of Glu 4 Lys revealed a link with allergic diseases. Thus, our results suggest that Glu 4 Lys in the LTC4S might be associated with allergic diseases.

Isolation of proliferation factor of immature T-cell clone in concanavalin A-stimulated splenocyte culture supernatant.

An athymic mouse-derived immature T-cell clone, N-9F, was not maintained by interleukin-2 alone but required another soluble factor, contained in concanavalin A-stimulated rat splenocyte culture supernatant, namely T cell growth factor (TCGF), for its proliferation. An N-9F-proliferation factor (NPF) was isolated in a pure form from TCGF. N-9F cells and immature thymocytes proliferated in the presence of NPF at 10-11-10-8 g/ml in a dose-dependent manner, but adult thymocytes were not stimulated by NPF. NPF increased DNA synthesis of N-9F. NPF increased CD4 and CD8 double negative thymocytes and CD8 single positive thymocytes in fetal thymus organ culture. A hamster anti-NPF antiserum possessing the capacity to neutralize N-9F proliferation activity of NPF decreased double negative thymocytes. The amino-terminal amino acid sequence of NPF was identified to be Ser-Leu-Pro-Cys-Asp-Ile-Cys-Lys-Thr-Val-Val-Thr-Glu-Ala-Cys-Asn-Leu-Leu-Lys-Asp- and was identical to that of rat saposin A. The apparent molecular weight of NPF, 16000, was comparable to that of saposin A. A rabbit anti-mouse recombinant His-tag (mrH)-saposin A antibody recognized a 16000 MW molecule in TCGF. A Hitrap-saposin A antibody column bound NPF and pulled down the NPF activity in TCGF. Thus, NPF in TCGF was a saposin A-like protein possessing the capacity for growth and differentiation of immature thymocytes.

[Evaluation before and after pranlukast administration with the QOL questionnaire (revised version 2001) for pediatric patients with bronchial asthma and their parents or caregivers].

We conducted a longitudinal investigation with the QOL questionnaire (revised version 2001) before and after the 4-week-administration of a leukotriene receptor antagonist pranlukast. A significant improvement in the < 4 yrs group was observed at week 1, and that in > or = 4 yrs group at week 2. Under these conditions, the overall QOL score, physical domains and mental domains, significantly improved in both the < 4 yrs group and the > or = 4 yrs group. Overall, a slight correlation was observed between ratio changes in QOL scores and differences in symptom scores. However, no correlation was found in part of patients, suggesting that the QOL questionnaire allows measurement of mental changes in the patients themselves and their parents or caregivers for therapeutic effects which cannot be determined with ordinary physical findings only. In "event present" group, a significant difference in physical and mental domains was revealed by the comparison of QOL scores before and after administration. And furthermore in "event absence" group, the p-value for physical domain and mental domain was 0.0505 and 0.0912 in the < 4 yrs group, respectively, 0.0101 and 0.0446 in the > or = 4 yrs group, respectively. The above results led us to consider the QOL questionnaire (revised version 2001) useful for routine medical care. Furthermore, pranlukast was considered useful for improvement not only of physical symptoms of bronchial asthma but also of the patient's QOL, although the placebo effects in this open trial must be considered.