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  • Jefferson Adams
    Jefferson Adams
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    Microwave Treatments of Wheat Can Confuse R5-antibody ELISA Gluten Tests

      Microwave treatments of wheat can trick R5-antibody ELISA tests to misread actual gluten content.

    Caption: Photo: CC--Marcin Wichary

    Celiac.com 02/17/2017 - In recent tests, researchers found that microwave treatment (MWT) of wet wheat kernels caused a striking reduction in R5-antibody-based ELISA gluten readings, reducing the readings to under 20 ppm, so that wheat could theoretically be labeled as gluten-free. However, the actual gluten content of the wheat remained unchanged. Just the test reading changed.

    The research team included C Gianfrani, G Mamone, B la Gatta, A Camarca, L Di Stasio, F Maurano, S Picascia, V Capozzi, G Perna, G Picariello, A Di Luccia. They are variously affiliated with the Institute of Protein Biochemistry, CNR, Naples, Italy, the Institute of Food Sciences, CNR Avellino, Italy, the Department of the Sciences of Agriculture, Food and Environment at the University of Foggia, Italy, the Institute of Food Sciences, CNR Avellino, Italy; Department of Agriculture, University of Naples, Portici (Na), Italy, the Department of Clinical and Experimental Medicine, University of Foggia, Foggia (Italy) and National Institute of Nuclear Physics, Section of Bari, Italy, and the Department of the Sciences of Agriculture, Food and Environment, University of Foggia, Italy.

    The failure of R5 Elisa to register gluten in MWT stands in stark contrast to analysis of gluten peptides by G12 antibody-based ELISA, mass spectrometry-based proteomics, and in vitro assay with T cells of celiac subjects, all three of which gave consistent results both before and after MWT.

    As to what caused the R5 Elisa to misread the MWT samples, an SDS-PAGE analysis and Raman spectroscopy showed that MWT reduced the alcohol solubility of gliadins, and altered the access of R5-antibody to the gluten epitopes. Thus, MWT neither destroys gluten nor modifies chemically the toxic epitopes, this contradicts claims that MWT of wheat kernels detoxifies gluten.

    This study provides evidence that R5-antibody ELISA alone is not effective to determine gluten levels in thermally treated wheat products.

    Gluten epitopes in processed wheat should be monitored using strategies based on combined immunoassays with T cells from celiacs, G12-antibody ELISA after proteolysis and proper molecular characterization.

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    Question 1: are companies that produce gluten free products using the R5 Elisa test alone to verify that their products are gluten free? Even in this country, there is no guarantee that some unscrupulous manufacturer would use bare minimum testing standards to produce a product for consumption while gaining maximum profit at our expense. Question 2: with cost cutting practices being used in all aspects of the health care industry, food/non-food industries, how do people know what tests are being used to verify the presence of celiac Disease (and other non-celiac diseases) when they truly do not know what's going on with their health? Even with information so readily available from so many sources, we, the patient and consumer, are vulnerable to exposure to gluten contamination which could have detrimental and devastating effects no matter how careful we are! With each visit to the emergency room because of gluten contamination, vigilance on my part becomes paramount to living the best way I know how. It would be nice to know that measures for testing were also paramount as well.

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    Important information to know! Would these microwave waves be the equivalent of at home microwaves or something more industrial? Separate issue: Has anyone else noticed issues with microwave food in general? (For example, there are times I make a safe meal at home and do not get sick, but if I microwave the same gluten free meal at work for lunch the next day, I get ill--similar to gluten, though a bit different. I know microwaves work fast by breaking the cell walls of food, but I'm not sure why I would feel ill due to that.)

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    Article: Microwave treatments of wheat can trick R5-antibody ELISA tests to misread actual gluten content. I was wondering what the government was going to do with the unsaleable wheat that is rotting in the silos. Celiac is a wide-ranging disease. Intake of gluten, yeast or yeast extract, egg, dairy, seed or flower oils results in dumping. Only cold pressed oils do not contain toxins. I told a co-worker; "If you want to know what foods and additives are toxic to the body, let me know, I'll ingest it and get right back to you!"

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  • About Me

    Jefferson Adams earned his B.A. and M.F.A. at Arizona State University, and has authored more than 2,000 articles on celiac disease. His coursework includes studies in biology, anatomy, medicine, and science. He previously served as Health News Examiner for Examiner.com, and provided health and medical content for Sharecare.com. Jefferson has spoken about celiac disease to the media, including an appearance on the KQED radio show Forum, and is the editor of the book "Cereal Killers" by Scott Adams and Ron Hoggan, Ed.D.

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    Researchers Discover Gluten-Degrading Bacteria in Mouth and Upper Gastro-Intestinal Tract
    Celiac.com 03/24/2014 - Two new studies have confirmed colonization of gluten-degrading bacteria in the human mouth and in the upper gastrointestinal tracts respectively.
    Both studies come out of the Department of Periodontology and Oral Biology, Boston University Henry M. Goldman School of Dental Medicine in Boston, Massachusetts. The research teams included Maram Zamakhchari, Guoxian Wei, Floyd Dewhirst, Jaeseop Lee, Detlef Schuppan, Frank G. Oppenheim, and Eva J. Helmerhorst.
    Gluten is notoriously hard for mammals to digest, because gliadin proteins resist mammalian proteolytic enzymes in the gut, so researchers wanted to find sources of gluten-digesting microbial enzymes from the upper gastro-intestinal tract. These microbial enzymes have the potential to neutralize the gluten peptides that act as celiac disease triggers.
    In the first study the researchers assessed proteolytic activity in suspended dental plaque towards a) gliadin-derived paranitroanilide(pNA)-linked synthetic enzyme substrates a mixture of natural gliadins and c) synthetic highly immunogenic gliadin peptides (33-mer of α2-gliadin and 26-mer of γ-gliadin).
    In addition, they conducted gliadin zymography to establish the approximate molecular weights and pH activity profiles of the gliadin-degrading oral enzymes and performed liquid iso-electric focusing to determine overall enzyme iso-electric points.
    Their results provide the first known evidence of gluten-degrading microorganisms associated with the upper gastro-intestinal tract.
    Such microorganisms may play a hitherto unappreciated role in the digestion of dietary gluten and thus protection from celiac disease in subjects at risk.
    In the second study, the team employed a selective plating strategy using gluten agar to obtain oral microorganisms with gluten-degrading capacity. They then used16S rDNA gene sequencing to carry out microbial speciations.
    To determine enzyme activity, they used gliadin-derived enzymatic substrates, gliadins in solution, gliadin zymography, and 33-mer a-gliadin and 26-mer c-gliadin immunogenic peptides.
    They separated fragments of the gliadin peptides by RP-HPLC, and structurally characterized them using mass spectrometry. They found that strains Rothia mucilaginosa and Rothia aeria showed high gluten-degrading activity. For example, gliadins (250 mg/ml) added to Rothia cell suspensions (OD620 1.2) degraded by 50% after 30 minutes of incubation.
    Importantly, the 33-mer and 26-mer immunogenic peptides were also cleaved, primarily C-terminal to Xaa-Pro-Gln (XPQ) and Xaa-Pro-Tyr (XPY). The major gliadin-degrading enzymes produced by the Rothia strains were 70–75 kDa in size, and the enzyme expressed by Rothia aeria was active over a wide pH range (pH 3–10).
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    Taken together, these studies suggest a potential for these bacteria to fuel the development of compounds that can degrade of harmful gluten peptides that trigger celiac disease in susceptible individuals.
    Source:
    PLoS One. 2011;6(9):e24455. doi: 10.1371/journal.pone.0024455. http://www.ncbi.nlm.nih.gov/pubmed/20948997

    Jefferson Adams
    Study Reviews Gluten Modification Efforts in Celiac Disease Therapies
    Celiac.com 03/31/2014 - Celiac disease is an autoimmune disorder that occurs in genetically susceptible individuals who carry the genetic markers HLA DQ2 or DQ8. About one in three people carry these genetic markers, while researchers estimate that the global prevalence of celiac disease is somewhere between one- and two-percent.
    A gluten-free diet remains the only treatment for celiac disease, but researchers are looking into new therapies aimed at gluten modification.
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    Unfortunately, the full study is only available to subscribers, but anyone with the inclination to subscribe can read it online.
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    Jefferson Adams
    Celiac.com 05/07/2014 - Current treatment for celiac disease is to eat only foods which are gluten-free. But, what about foods processed to remove gluten? Is it safe for people with celiac disease to eat foods that have been processed to remove gluten?
    Processing may render gluten-containing foods technically safe celiac patients, but so far live safety testing can only be performed on actual patients, not in laboratory computer models.
    A team of researchers recently set out to test the safety of germinated rye sourdough in a celiac disease model based on the adoptive transfer of prolamin-primed memory T cells into lymphopenic mice. The research team included T.L. Freitag, J. Loponen, M. Messing, V. Zevallos, L.C. Andersson, T. Sontag-Strohm, P. Saavalainen, D. Schuppan, H. Salovaara, S. Meri. They are variously affiliated with the Department of Bacteriology and Immunology at the Haartman Institute of the University of Helsinki in Helsinki, Finland.
    For their study, they modified a celiac disease mouse model to test antigenicity and inflammatory effects of germinated rye sourdough, a food product characterized by extensive prolamin hydrolysis.
    The team then injected Lymphopenic Rag1(-/-) or nude mice with splenic CD4(+)CD62L(-)CD44 high-memory T cells from gliadin- or secalin-immunized wild-type donor mice.
    The team found that:
    Rag1(-/-) recipients challenged with wheat or rye gluten lost more body weight and developed more severe histological duodenitis than mice on gluten-free diet. This correlated with increased secretion of IFNγ, IL-2, and IL-17 by secalin-restimulated splenocytes. In vitro gluten testing using competitive R5 ELISA showed widespread degradation of the gluten R5 epitope in germinated rye sourdough. However, in nude mice challenged with germinated rye sourdough (vs. native rye sourdough), serum anti-secalin IgG/CD4(+) T helper 1-associated IgG2c titers were only reduced, but not eliminated. In addition, they found no reductions in body weight loss, histological duodenitis, or T cell cytokine secretion in Rag1(-/-) recipients challenged accordingly.
    From the results, they concluded that Prolamin-primed CD4(+)CD62L(-)CD44 high-memory T cells do induce gluten-sensitive enteropathy in Rag1(-/-) mice.
    Moreover, germination of rye sourdough does not completely hydrolyze the secalin peptides, which retain B and T cell stimulatory capacity and remain harmful to the intestinal mucosa in this celiac disease model.
    Current antibody-based prolamin detection methods may fail to detect antigenic gluten fragments in processed cereal food products.
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    Am J Physiol Gastrointest Liver Physiol. 2014 Mar;306(6):G526-34. doi: 10.1152/ajpgi.00136.2013. Epub 2014 Jan 23.

    Jefferson Adams
    AN-PEP Digestive Enzymes Degrade Gluten Better Than Most Other Digestive Enzymes
    Celiac.com 06/22/2015 - Currently available digestive enzymes do not fully degrade gluten, and are thus of questionable use for people with celiac disease or gluten intolerance, say a team of researchers. Prior research had shown that post-proline cutting enzyme effectively degrade the immunogenic gluten peptides. Several existing digestive enzyme supplements claim to promote gluten degradation.
    The research team set out to assess the degradation of immunogenic gluten epitopes by currently available digestive enzymes. The team included G. Janssen, C. Christis, Y. Kooy-Winkelaar, L. Edens, D. Smith, P. van Veelen, and F. Koning. They are variously affiliated with the Department of Immunohematology and Blood Transfusion, Leiden University Medical Centre, Leiden, The Netherlands, DSM Food Specialties in Delft, The Netherlands, and DSM Food Specialties in South Bend, Indiana, USA.
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    They found that the enzyme supplements leave the nine immunogenic epitopes of the 26-mer and 33-mer gliadin fragments largely intact. This is due to the high proline content of gluten molecules, which prevents gastrointestinal proteases from fully degrading them, leaving large proline-rich gluten fragments intact, including an immunogenic 33-mer from α-gliadin and a 26-mer from γ-gliadin.
    These latter peptides can trigger pro-inflammatory T cell responses resulting in tissue remodeling, malnutrition and a variety of other complications.
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    Source:
    PLoS One. 2015 Jun 1;10(6):e0128065. doi: 10.1371/journal.pone.0128065.

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