• Clinical and Experimental Pediatrics
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• v.54 no.10
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• pp.414-421
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• 2011

Purpose: Recently, an increase in the number of patients sensitized to rice allergen with or without clinical symptoms has been reported. This study was designed to determine the major allergens in rice and their clinical significance. Methods: Twenty-four children (15 boys and 9 girls; mean age, 16.3 months) with allergic disease, who were sensitized to rice antigen (by UniCAP) in the Pediatric Allergy Respiratory Center at Soonchunhyang University Hospital, were enrolled in this study. The allergenicity of various types of rice (raw, cooked, and heat-treated, simulated gastric fluid [SGF], and simulated intestinal fluid [SIF]) was investigated using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoglobulin E (IgE) immunoblots. The patients' medical records, including laboratory data and allergy symptoms after ingestion of rice were reviewed. Results: Patients were sensitized to an average of 13.5 food antigens and their mean total IgE was 6,888.7 kU/L. In SDS-PAGE, more than 16 protein bands were observed in the raw rice, whereas only 14-16 kDa and 31-35 kDa protein bands were observed in cooked rice. The common SDS-PAGE protein bands observed in SGF-, SIF-, and heat-treated rice were 9, 14, and 31 kDa. In a heated-rice IgE immunoblot, protein bands of 9, 14, and 31-33 kDa were found in 27.8%, 38.9%, and 38.9% of all sera, respectively, and in 50%, 50%, and 75%, of ser a from the 4 symptomatic patients, respectively. Conclusion: The 9-, 14-, and 31-kDa protein bands appeared to be the major allergens responsible for rice allergy symptoms.

• Food Science and Biotechnology
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• v.15 no.3
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• pp.385-391
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• 2006

In Korea, different kinds of genetically modified (GM) crops are under development, including GM-rice expressing insecticidal crystal (Cry) proteins of Bacillus thuringiensis (Bt) modified to change a single amino acid. In this study, amino acid (aa) sequences of modified Cry proteins were compared to that of known allergens, and Cry proteins expressed in GM-rice were identified by using Cry protein specific polyclonal antibody. The antigen-antibody reactions were compared between GM and commercial rice to assess the allergic risk of Cry proteins. This analysis showed no known allergen to have more than 35% aa sequence homology with modified Cry proteins in Bt rice over an 80 aa window or to have more than 8 consecutive identical aa. Sera from allergic patients showed some IgE reactivity via immunoblotting and enzyme-linked immunosorbent assay (ELISA), although no differences were seen between GM and commercial rice. Based on these results we conclude that GM rice with modified Cry proteins has no differences in its protein composition or allergenicity relative to commercial rice.

• Korean Journal of Agricultural Science
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• v.45 no.2
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• pp.248-257
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• 2018

Overexpression of AtCYP78A7, a gene encoding a cytochrome P450 protein, has been reported to improve tolerance to drought stress in genetically modified (GM) rice (Oryza sativa L.). The aim of this study was to evaluate the potential allergenicity and acute oral toxicity of the AtCYP78A7 protein expressed in GM rice. Bioinformatics analysis of the amino acid sequence of AtCYP78A7 did not identify any similarities with any known allergens or toxins. It showed that no known allergen had more than a 35% amino acid sequence homology with the AtCYP78A7 protein over an 80 amino acid window or more than 8 consecutive identical amino acids. The gene encoding the AtCYP78A7 protein was cloned in the pGEX-4T-1 vector and expressed in E. coli. Then, the AtCYP78A7 protein was purified and analyzed for acute oral toxicity. The AtCYP78A7 protein was fed at a dose of 2,000 mg/kg body weight in mice, and the changes in mortalities, clinical findings, and body weight were monitored for 14 days after the dosing. Necropsy was carried out on day 14. The protein did not cause any adverse effects when it was orally administered to mice at 2000 mg/kg body weight. These results indicate that the AtCYP78A7 protein expressed in GM rice would not be a potential allergen or toxin.

• Journal of Life Science
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• v.17 no.11
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• pp.1492-1496
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• 2007

In vitro IgE class switching could be induced through co-culture of CD40L-expressing KU812 cells and CD40-expressing B cells in the presence of IL-4 or IL-13. It has been generated several B cell lines, which produce rice allergen (RA)-specific IgM antibody by in witγo immunization (IVI) using peripheral blood lymphocyte (PBL). In this study, induction of RA-specific IgE antibody by KU812 cells was attempted. Before co-culture, we determined the CD40 expression in RA-specific B cell lines, RA9G11 and the CD40 ligand (CD40L) expression in activated KU812 cells by treatments with phorbol myristate acetate (PMA) and ionomycin for 6 hrs. Flow cytometric analysis shown that RA9G11 and activated KU812 cells expressed high level of CD40 and CD40L, respectively. RA9G11 cells were cultured with activated KU812 cells for 12 days in the presence of IL-4 for IgE class switching. Mature $C{\varepsilon}$ mRNA level and RA-specific IgE spot forming cells (SFC) were observed in all culture condition, and especially, high level of RA-specific IgE synthesis was determined the same ratio of RA9G11 and activated KU812 cells in the presence of 50U IL-4. Therefore, induction of RA-specific IgE synthesis by activated KU812 cells can be contributed in the application for allergic therapy and prevention.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.9 no.1
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• pp.80-84
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• 2006

Rice allergen has low antigenicity, and thus, anaphylactoid reactions to rice are exceedingly rare. We experienced a case of isolated rice allergy in a 5 month-old girl who had been fed a milk formula without incident. However, after feeding a powdered weaning milk formula containing rice, she developed symptoms of projectile vomiting and diarrhea, at this time rice specific antigen tests were all negative. One month later a challenge test was performed using a rice gruel, and her symptoms recurred. Endoscopic and microscopic findings showed hyperemic mucosa in the duodenum and subtotal villous atrophy. Thereafter, she showed no adverse reaction to almost all foods appropriate for her age, but after feeding rice gruel at 10 months, she developed symptoms of cyanosis and vomiting. However, none of the allergic symptoms were demonstrated at 13 months upon repeated challenge test. Currently, she is 28 months old and tolerates all foods including rice.

• Food Science and Biotechnology
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• v.16 no.6
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• pp.935-942
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• 2007

The stem bark of Rhus verniciflua (RVSB) has been used in herbal medicine to treat diabetes mellitus and stomach ailments for thousands of years in Korea, despite its content of the plant allergen, urushiol. A new biological approach for the removal of urushiol from RVSB using mushrooms is described. All mushroom species (11 sp.) employed in this study were able to grow on RVSB, although the growth rate (mm/day) was lower than the control (sawdust). The components of urushiol congeners [C15 triene (m/z 314), C15 diene (m/z 316), C15 monoene (m/z 318), and C15 saturated (m/z 320)] were purified by HPLC and identified by GC-MS. A C15:3 (3-pentadecatrienly catechol) was found to be most abundant in RVSB. Urushiol analogues decreased remarkably from 154.15 to 10.73 mg/100 g (approximately 93%) by Fomitella fraxinea, whereas Trametes vercicolor showed only a 1.46% degradation capacity despite its 2 fold higher growth rate. Similarly, laccase activity was found to be high for F. fraxinea and low for T. vercicolor. Moreover, approximately 98% detoxification was accomplished by F. fraxinea cultivated on RVSB supplemented with 20%(w/w) rice bran. These findings suggest that mushrooms can be used in the detoxification of RVSB.