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Impact of Microwaving on the Protein Content and Microbial Levels of Whole Wheat Flour for Use in Oral Immunotherapy
AB276 Abstracts
865
The Utility of BAT in Diagnosing Treenut Allergy
MONDAY
Michael R. Goldberg, MD, PhD1, Michael Y. Appel, PhD1, Liat Nachshon, MD1, Mor Carmel, RD1, Michael B. Levy, MD, FAAAAI1, and Arnon Elizur, MD2,3; 1Allergy, Immunology and Pediatric Pulmonary Institute, Assaf Harofeh Medical Center, Beer Yaakov, Israel, 2Department of Pediatrics, Sackler School of Medicine, Tel Aviv, Israel, 3Allergy, Immunology and Pediatric Pulmonology, Assaf Harofeh Medical Center, Beer Yaakov, Israel. RATIONALE: Patients with known allergy to a single tree-nut are often sensitized to other tree-nuts, requiring an oral food challenge (OFC) for definitive diagnosis. Since OFCs are time-consuming and not without risk, we evaluated the utility of the basophil activation test (BAT) to diagnose true clinical allergy. METHODS: Patients with a history of reaction to tree nuts (walnut, hazelnut, cashew, pistachio, almond, and pecan) were evaluated. OFCs were performed to confirm clinical reactivity for all nuts except if they were being currently consumed or clinically contraindicated based on a recent severe reaction. Induced basophil CD63 expression was determined and evaluated against the patients’ clinical allergic status for each nut, respectively. RESULTS: The allergic status of patients was determined (walnut:23/30 [77%], hazelnut: 7/28 [25%], cashew: 12/28 [43%], pistachio: 6/27 [22%], pecan: 13/28 [46%]). No patients were found allergic to almond (0/29). The performance of BAT for allergy diagnosis was evaluated by Receiver operating characteristic (ROC) curve analysis, yielding an area under the curve (AUC) 6 SE of 0.9660.035, 0.8760.067, 0.9960.014, 0.9160.059, 0.9360.060 for walnut, hazelnut, cashew, pistachio, and pecan, respectively. Using a critical test value of 5% CD63 induction, we obtained paired sensitivities and specificities of 96%, 86% (walnut); 86%,76% (hazelnut); 83%,100% (cashew); 100%, 86% (pistachio); 85%, 100% (pecan). False positive BAT (>5% CD63) were observed for 3/14 (21%) of patients with zero or one nut allergies, and 6/16 (38%) patients with multiple nut allergies. CONCLUSIONS: Depending on the nut tested, BAT may obviate the need for OFC to diagnose or rule out treenut allergy.
866
Impact of Microwaving on the Protein Content and Microbial Levels of Whole Wheat Flour for Use in Oral Immunotherapy
Anusha Penumarti, PhD1, Nicole Szczepanski1, Janelle Kesselring1, Elizabeth Gabel1, Edwin Kim, MD1, A. Wesley Burks, MD2, and Michael D. Kulis, PhD1; 1University of North Carolina, Chapel Hill, NC, 2University of North Carolina at Chapel Hill, Chapel Hill, NC. RATIONALE: Food products used in Oral Immunotherapy studies conducted under INDs have to meet specific criteria for allergen content and bioburden. We studied the effect of microwaving on the protein content and bioburden of whole wheat flour proteins (Tri a 19 and Tri a 37). METHODS: SDS-PAGE analysis coupled with densitometric scanning was conducted on whole wheat flour subjected to microwaving at 1000 Watts for increasing lengths of time (0min, 1min, 2min, 4min, 7min and 10min) to determine the effect of microwaving on protein content. Thermally processed and unprocessed whole wheat flour was tested for the presence of Escherichia coli, Salmonella, aerobic bacteria, mold and yeast levels. RESULTS: Microwaving wheat flour for varying times resulted in <10% variance in the content of Tri a 19 and Tri a 37 proteins as revealed by SDSPAGE and densitometry analysis. Bioburden testing revealed a significant decrease in aerobic plate count (>2500 cfu/g at 0 min to 470 cfu/g at 10 min), yeast (>2500 cfu/g at 0 min to <10 cfu/g at 10 min), mold (150 cfu/g at 0 min to <10 cfu/g at 10 min), Escherichia coli and Salmonella levels (Presumptive/10 g at 0 min to Negative/10 g at 10 min) with microwaving.
J ALLERGY CLIN IMMUNOL FEBRUARY 2017
Importantly, the levels of these microbes after 10 minutes of microwaving met criteria established by USDA for an orally delivered drug product. CONCLUSIONS: Microwaving of whole wheat flour leads to a significant decrease of bioburden levels without significantly altering the protein content. Future studies will determine the effect of microwaving on the allergenicity of wheat proteins using Western blotting, ELISA and basophil activation testing.
865
The Utility of BAT in Diagnosing Treenut Allergy
MONDAY
Michael R. Goldberg, MD, PhD1, Michael Y. Appel, PhD1, Liat Nachshon, MD1, Mor Carmel, RD1, Michael B. Levy, MD, FAAAAI1, and Arnon Elizur, MD2,3; 1Allergy, Immunology and Pediatric Pulmonary Institute, Assaf Harofeh Medical Center, Beer Yaakov, Israel, 2Department of Pediatrics, Sackler School of Medicine, Tel Aviv, Israel, 3Allergy, Immunology and Pediatric Pulmonology, Assaf Harofeh Medical Center, Beer Yaakov, Israel. RATIONALE: Patients with known allergy to a single tree-nut are often sensitized to other tree-nuts, requiring an oral food challenge (OFC) for definitive diagnosis. Since OFCs are time-consuming and not without risk, we evaluated the utility of the basophil activation test (BAT) to diagnose true clinical allergy. METHODS: Patients with a history of reaction to tree nuts (walnut, hazelnut, cashew, pistachio, almond, and pecan) were evaluated. OFCs were performed to confirm clinical reactivity for all nuts except if they were being currently consumed or clinically contraindicated based on a recent severe reaction. Induced basophil CD63 expression was determined and evaluated against the patients’ clinical allergic status for each nut, respectively. RESULTS: The allergic status of patients was determined (walnut:23/30 [77%], hazelnut: 7/28 [25%], cashew: 12/28 [43%], pistachio: 6/27 [22%], pecan: 13/28 [46%]). No patients were found allergic to almond (0/29). The performance of BAT for allergy diagnosis was evaluated by Receiver operating characteristic (ROC) curve analysis, yielding an area under the curve (AUC) 6 SE of 0.9660.035, 0.8760.067, 0.9960.014, 0.9160.059, 0.9360.060 for walnut, hazelnut, cashew, pistachio, and pecan, respectively. Using a critical test value of 5% CD63 induction, we obtained paired sensitivities and specificities of 96%, 86% (walnut); 86%,76% (hazelnut); 83%,100% (cashew); 100%, 86% (pistachio); 85%, 100% (pecan). False positive BAT (>5% CD63) were observed for 3/14 (21%) of patients with zero or one nut allergies, and 6/16 (38%) patients with multiple nut allergies. CONCLUSIONS: Depending on the nut tested, BAT may obviate the need for OFC to diagnose or rule out treenut allergy.
866
Impact of Microwaving on the Protein Content and Microbial Levels of Whole Wheat Flour for Use in Oral Immunotherapy
Anusha Penumarti, PhD1, Nicole Szczepanski1, Janelle Kesselring1, Elizabeth Gabel1, Edwin Kim, MD1, A. Wesley Burks, MD2, and Michael D. Kulis, PhD1; 1University of North Carolina, Chapel Hill, NC, 2University of North Carolina at Chapel Hill, Chapel Hill, NC. RATIONALE: Food products used in Oral Immunotherapy studies conducted under INDs have to meet specific criteria for allergen content and bioburden. We studied the effect of microwaving on the protein content and bioburden of whole wheat flour proteins (Tri a 19 and Tri a 37). METHODS: SDS-PAGE analysis coupled with densitometric scanning was conducted on whole wheat flour subjected to microwaving at 1000 Watts for increasing lengths of time (0min, 1min, 2min, 4min, 7min and 10min) to determine the effect of microwaving on protein content. Thermally processed and unprocessed whole wheat flour was tested for the presence of Escherichia coli, Salmonella, aerobic bacteria, mold and yeast levels. RESULTS: Microwaving wheat flour for varying times resulted in <10% variance in the content of Tri a 19 and Tri a 37 proteins as revealed by SDSPAGE and densitometry analysis. Bioburden testing revealed a significant decrease in aerobic plate count (>2500 cfu/g at 0 min to 470 cfu/g at 10 min), yeast (>2500 cfu/g at 0 min to <10 cfu/g at 10 min), mold (150 cfu/g at 0 min to <10 cfu/g at 10 min), Escherichia coli and Salmonella levels (Presumptive/10 g at 0 min to Negative/10 g at 10 min) with microwaving.
J ALLERGY CLIN IMMUNOL FEBRUARY 2017
Importantly, the levels of these microbes after 10 minutes of microwaving met criteria established by USDA for an orally delivered drug product. CONCLUSIONS: Microwaving of whole wheat flour leads to a significant decrease of bioburden levels without significantly altering the protein content. Future studies will determine the effect of microwaving on the allergenicity of wheat proteins using Western blotting, ELISA and basophil activation testing.