title: Characterization of Antibodies for Grain-Specific Gluten Detection.
abstract: Gluten ingestion causes immunoglobulin E (IgE)-mediated allergy or celiac disease in sensitive individuals, and a strict gluten-free diet greatly limits food choices. Immunoassays such as enzyme-linked immunosorbent assay (ELISA) are used to quantify gluten to ensure labeling compliance of gluten-free foods. Anti-gluten antibodies may not exhibit equal affinity to gluten from wheat, rye, and barley. Moreover, because wheat gluten is commonly used as a calibrator in ELISA, accurate gluten quantitation from rye and barley contaminated foods may be compromised. Immunoassays utilizing grain-specific antibodies and calibrators may help improve gluten quantitation. In this study, polyclonal antibodies raised against gluten-containing grain-specific peptides were characterized for their immunoreactivity to gluten from different grain sources. Strong immunoreactivity to multiple gluten polypeptides from wheat, rye, and barley was observed in the range 34 to 43 kDa with anti-gliadin, 11 to 15 and 72 to 95 kDa with anti-secalin, and 30 to 43 kDa with anti-hordein peptide antibodies, respectively. Minimal or no cross-reactivity with gluten from other grains was observed among these antibodies. The anti-consensus peptide antibody raised against a repetitive amino acid sequence of proline and glutamine exhibited immunoreactivity to gluten from wheat, rye, barley, and oat. The antibodies exhibited similar immunoreactivity with most of the corresponding grain cultivars by ELISA. The high specificity and minimal cross-reactivity of grain-specific antibodies suggest their potential use in immunoassays for accurate gluten quantitation.
authors.affiliation: Immunobiology Branch, Office of Applied Research and Safety Assessment, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, 8301 Muirkirk Road, Laurel, MD, 20708, U.S.A.
authors.forename: Girdhari M
authors.initials: GM
authors.lastname: Sharma
authors.affiliation: Immunobiology Branch, Office of Applied Research and Safety Assessment, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, 8301 Muirkirk Road, Laurel, MD, 20708, U.S.A.
authors.forename: Prasad
authors.initials: P
authors.lastname: Rallabhandi
authors.affiliation: Immunobiology Branch, Office of Applied Research and Safety Assessment, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, 8301 Muirkirk Road, Laurel, MD, 20708, U.S.A.
authors.forename: Kristina M
authors.initials: KM
authors.lastname: Williams
authors.affiliation: Joint Inst. for Food Safety and Applied Nutrition, Univ. of Maryland, 5201, Paint Branch Parkway, College Park, MD, 20742, U.S.A.
authors.forename: Autusa
authors.initials: A
authors.lastname: Pahlavan
mesh_terms: D002446:Celiac Disease / Q000178:diet therapy; D003429:Cross Reactions; D055050:Diet, Gluten-Free; D002523:Edible Grain / Q000737:chemistry*; D004797:Enzyme-Linked Immunosorbent Assay; D005903:Gliadin / Q000276:immunology; D005983:Glutens / Q000032:analysis* / Q000276:immunology; D001467:Hordeum / Q000737:chemistry*; D006801:Humans; D007073:Immunoglobulin E / Q000032:analysis*; D010455:Peptides / Q000032:analysis; D012434:Secale / Q000737:chemistry*; D012680:Sensitivity and Specificity; D014908:Triticum / Q000737:chemistry*
chemical_list: D010455:Peptides; D007073:Immunoglobulin E; D005983:Glutens; D005903:Gliadin
keywords: antibodies; gluten; grain-specific; immunoassay