- Email: [email protected]
In vitro Hypoallergenicity of Peanut Protein-Blueberry Polyphenol Aggregate Particles
Abstracts AB139
J ALLERGY CLIN IMMUNOL VOLUME 139, NUMBER 2
In vitro Hypoallergenicity of Peanut ProteinBlueberry Polyphenol Aggregate Particles
Nathalie Plundrich1, Rishipal Bansode2, Leonard Williams2, and Mary Ann Lila1; 1North Carolina State University, Plants for Human Health Institute, Kannapolis, NC, 2North Carolina Agricultural and Technical State University, Center for Excellence in Post-Harvest Technologies, Kannapolis, NC. RATIONALE: The effector phase of the peanut (PN) allergic reaction involves crosslinking of PN allergen epitopes with PN-specific IgE located on mast cell and basophil surfaces causing them to degranulate and to release inflammatory compounds. Plant-derived polyphenolic compounds are able to bind to proteins. In this study, stable aggregate particles comprised of PN proteins and blueberry pomace polyphenols were investigated for their allergen response potential by binding to IgE in vitro. METHODS: Peanut protein-blueberry pomace polyphenol aggregate particles were created by complexing lowbush blueberry (Vaccinium angustifolium) pomace polyphenols with roasted PN flour. Particles containing 5 to 40% polyphenols were created. For the detection of PN-specific IgE binding by PN proteins, immunoblotting was performed with pooled plasma from seven PN-allergic individuals. RBL-2H3 mast cells were exposed to aggregate particles or PN flour and evaluated for markers of degranulation (b-hexosaminidase and histamine). RESULTS: IgE binding capacity to PN proteins in aggregate particles was significantly decreased (p<0.05) in the 15, 30 and 40% polyphenol samples by 21, 30 and 31% compared to uncomplexed PN proteins, respectively. Anti-DNP-IgE-sensitized RBL-2H3 cells challenged with DNP-BSA and Ionomycin in the presence of aggregate particles were evaluated for their release of b-hexosaminidase and histamine. Aggregate particles with lower %polyphenol concentrations appeared to mitigate Ionomycin induced-degranulation. CONCLUSIONS: Results suggest the modification of PN proteins with blueberry pomace polyphenols led to the formation of aggregate particles with reduced allergenic potential. Future trials are warranted to investigate the immunomodulatory mechanisms of the aggregate particles.
444
Building a Pediatric Food Allergy Natural History Registry
Jesse Blumenstock, MS (c)1, Serena Chan, PhD2, Ruixuan Zhou3, Marjorie Yarbrough, MPH1, Madeline Walkner4, Paul J. Bryce, PhD5,6, Anne Marie Singh, MD7,8, and Ruchi S. Gupta, MD, MPH1,9; 1Northwestern University, Chicago, IL, 2Univeristy of Illinois, Champaign, IL, 3 University of Illinois, Champaign, IL, 4Ann and Robert H Lurie Children’s Hospital - Chicago, Chicago, IL, 5Northwestern Feinberg School of Medicine, Chicago, IL, 6Division of Allergy-Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, 7Division of Allergy & Immunology, Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL, 8 Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, IL, 9 Ann and Robert H. Lurie Children’s Hospital of Chicago, Chicago, IL. RATIONALE: Despite affecting up to 6 million children nationwide, the natural history of food allergy is not well understood. Food allergy affects individuals through both clinical manifestations and its impact on family and community. To obtain a comprehensive understanding of the natural course of food allergy and its effects, we have developed a prospective pediatric food allergy registry. METHODS: We have begun recruiting families with one or more children with food allergy into a prospective registry. We are analyzing children’s medical records and surveying caregivers about reaction history and how food allergy affects their child and their family. This data will be analyzed to determine reaction patterns, predictors of tolerance and severity, and psychosocial effects. RESULTS: Currently, 182 families are enrolled from two clinics. Followup surveys cover quality of life, GI symptoms, parental social support, anxiety and child-peer relations, self-efficacy, accidental ingestion, therapy
choice, food allergy knowledge, school/daycare experience, and management of comorbid conditions. Preliminary results of completed subjects (N5158) indicate respondents are mostly male (65.2%), white (76.6%), with an average age of 6.4 years (SD53.7). The majority of respondents (34.2%, N554) are currently allergic to five or more foods. Peanut (67.1%, N5106), tree nuts (65.2%, N5103), and egg (32.3%, N551) are the most prevalent allergens. CONCLUSIONS: As additional data is collected, we will analyze parentreported survey responses in conjunction with lab and food challenge data to determine predictors of tolerance, severity, and psychosocial effects of food allergy on the lives of children and their families.
445
Tolerance of Partially Hydrolyzed Whey Formula in Cow's Milk Allergic Patients
Maureen S. Egan, MD1, Tricia D. Lee, MD2, Jade Andrade2, Galina Grishina, MS2, Michelle Mishoe2, Gustavo Gimenez, MSc2, Hugh A. Sampson, MD, FAAAAI3, and Supinda Bunyavanich3,4; 1Section of Allergy & Immunology, Department of Pediatrics. Children’s Hospital of Colorado., Denver, CO, 2Division of Allergy & Immunology, Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY, 3 Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY, 4Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY. RATIONALE: The identification of children with cow’s milk allergy (CMA) who can tolerate partially hydrolyzed whey formula (pHWF) could enable their use of pHWF, which is better tasting and less expensive than hypoallergenic formulas. We sought to identify the current prevalence and immune profiles of children with CMA who tolerate pHWF. METHODS: Children with cow’s milk sensitization (by skin prick test (SPT) or specific IgE (sIgE)) and recent reaction to cow’s milk underwent oral food challenge (OFC) to pHWF, SPT, sIgE and laboratory testing, including a Luminex-based peptide assay (LPA) to fully characterize their CMA. LPA is a high-throughput assay that examines IgE binding to sequential allergenic epitopes in milk. RESULTS: The first 10 patients, mean age 61.8 months (range 11 months to 10.8 years), all failed OFC to pHWF. Recruitment was terminated based on statistical calculations supporting marginal benefit to additional recruitment. Among the participants, milk sIgE ranged from 1.16 kUA/L to >100 kUA/L. Reaction to pHWF was independent of sensitization profile (casein-predominant, whey predominant, vs. casein and whey cosensitization). Immunoblots and LPA supported that the patients reacted to residual casein in pHWF. LPA demonstrated differential binding of 10 casein protein epitopes based on SPT and casein sIgE. CONCLUSIONS: The prevalence of pHWF tolerance was 0% in a USbased cohort of CMA children, with immune profiling supporting that residual casein in pHWF was responsible. This low rate of tolerance is in contrast to previously reported rates from small European studies. Consistent with current guidelines, pHWF should be avoided in children with CMA.
SUNDAY
443
J ALLERGY CLIN IMMUNOL VOLUME 139, NUMBER 2
In vitro Hypoallergenicity of Peanut ProteinBlueberry Polyphenol Aggregate Particles
Nathalie Plundrich1, Rishipal Bansode2, Leonard Williams2, and Mary Ann Lila1; 1North Carolina State University, Plants for Human Health Institute, Kannapolis, NC, 2North Carolina Agricultural and Technical State University, Center for Excellence in Post-Harvest Technologies, Kannapolis, NC. RATIONALE: The effector phase of the peanut (PN) allergic reaction involves crosslinking of PN allergen epitopes with PN-specific IgE located on mast cell and basophil surfaces causing them to degranulate and to release inflammatory compounds. Plant-derived polyphenolic compounds are able to bind to proteins. In this study, stable aggregate particles comprised of PN proteins and blueberry pomace polyphenols were investigated for their allergen response potential by binding to IgE in vitro. METHODS: Peanut protein-blueberry pomace polyphenol aggregate particles were created by complexing lowbush blueberry (Vaccinium angustifolium) pomace polyphenols with roasted PN flour. Particles containing 5 to 40% polyphenols were created. For the detection of PN-specific IgE binding by PN proteins, immunoblotting was performed with pooled plasma from seven PN-allergic individuals. RBL-2H3 mast cells were exposed to aggregate particles or PN flour and evaluated for markers of degranulation (b-hexosaminidase and histamine). RESULTS: IgE binding capacity to PN proteins in aggregate particles was significantly decreased (p<0.05) in the 15, 30 and 40% polyphenol samples by 21, 30 and 31% compared to uncomplexed PN proteins, respectively. Anti-DNP-IgE-sensitized RBL-2H3 cells challenged with DNP-BSA and Ionomycin in the presence of aggregate particles were evaluated for their release of b-hexosaminidase and histamine. Aggregate particles with lower %polyphenol concentrations appeared to mitigate Ionomycin induced-degranulation. CONCLUSIONS: Results suggest the modification of PN proteins with blueberry pomace polyphenols led to the formation of aggregate particles with reduced allergenic potential. Future trials are warranted to investigate the immunomodulatory mechanisms of the aggregate particles.
444
Building a Pediatric Food Allergy Natural History Registry
Jesse Blumenstock, MS (c)1, Serena Chan, PhD2, Ruixuan Zhou3, Marjorie Yarbrough, MPH1, Madeline Walkner4, Paul J. Bryce, PhD5,6, Anne Marie Singh, MD7,8, and Ruchi S. Gupta, MD, MPH1,9; 1Northwestern University, Chicago, IL, 2Univeristy of Illinois, Champaign, IL, 3 University of Illinois, Champaign, IL, 4Ann and Robert H Lurie Children’s Hospital - Chicago, Chicago, IL, 5Northwestern Feinberg School of Medicine, Chicago, IL, 6Division of Allergy-Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, 7Division of Allergy & Immunology, Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL, 8 Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, IL, 9 Ann and Robert H. Lurie Children’s Hospital of Chicago, Chicago, IL. RATIONALE: Despite affecting up to 6 million children nationwide, the natural history of food allergy is not well understood. Food allergy affects individuals through both clinical manifestations and its impact on family and community. To obtain a comprehensive understanding of the natural course of food allergy and its effects, we have developed a prospective pediatric food allergy registry. METHODS: We have begun recruiting families with one or more children with food allergy into a prospective registry. We are analyzing children’s medical records and surveying caregivers about reaction history and how food allergy affects their child and their family. This data will be analyzed to determine reaction patterns, predictors of tolerance and severity, and psychosocial effects. RESULTS: Currently, 182 families are enrolled from two clinics. Followup surveys cover quality of life, GI symptoms, parental social support, anxiety and child-peer relations, self-efficacy, accidental ingestion, therapy
choice, food allergy knowledge, school/daycare experience, and management of comorbid conditions. Preliminary results of completed subjects (N5158) indicate respondents are mostly male (65.2%), white (76.6%), with an average age of 6.4 years (SD53.7). The majority of respondents (34.2%, N554) are currently allergic to five or more foods. Peanut (67.1%, N5106), tree nuts (65.2%, N5103), and egg (32.3%, N551) are the most prevalent allergens. CONCLUSIONS: As additional data is collected, we will analyze parentreported survey responses in conjunction with lab and food challenge data to determine predictors of tolerance, severity, and psychosocial effects of food allergy on the lives of children and their families.
445
Tolerance of Partially Hydrolyzed Whey Formula in Cow's Milk Allergic Patients
Maureen S. Egan, MD1, Tricia D. Lee, MD2, Jade Andrade2, Galina Grishina, MS2, Michelle Mishoe2, Gustavo Gimenez, MSc2, Hugh A. Sampson, MD, FAAAAI3, and Supinda Bunyavanich3,4; 1Section of Allergy & Immunology, Department of Pediatrics. Children’s Hospital of Colorado., Denver, CO, 2Division of Allergy & Immunology, Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY, 3 Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY, 4Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY. RATIONALE: The identification of children with cow’s milk allergy (CMA) who can tolerate partially hydrolyzed whey formula (pHWF) could enable their use of pHWF, which is better tasting and less expensive than hypoallergenic formulas. We sought to identify the current prevalence and immune profiles of children with CMA who tolerate pHWF. METHODS: Children with cow’s milk sensitization (by skin prick test (SPT) or specific IgE (sIgE)) and recent reaction to cow’s milk underwent oral food challenge (OFC) to pHWF, SPT, sIgE and laboratory testing, including a Luminex-based peptide assay (LPA) to fully characterize their CMA. LPA is a high-throughput assay that examines IgE binding to sequential allergenic epitopes in milk. RESULTS: The first 10 patients, mean age 61.8 months (range 11 months to 10.8 years), all failed OFC to pHWF. Recruitment was terminated based on statistical calculations supporting marginal benefit to additional recruitment. Among the participants, milk sIgE ranged from 1.16 kUA/L to >100 kUA/L. Reaction to pHWF was independent of sensitization profile (casein-predominant, whey predominant, vs. casein and whey cosensitization). Immunoblots and LPA supported that the patients reacted to residual casein in pHWF. LPA demonstrated differential binding of 10 casein protein epitopes based on SPT and casein sIgE. CONCLUSIONS: The prevalence of pHWF tolerance was 0% in a USbased cohort of CMA children, with immune profiling supporting that residual casein in pHWF was responsible. This low rate of tolerance is in contrast to previously reported rates from small European studies. Consistent with current guidelines, pHWF should be avoided in children with CMA.
SUNDAY
443