Can we have allergen-free foods?

Biotechnology can be used to reduce allergenicity. Much attention has been focused on the possibility that modification of foods through recombinant DNA technology could unintentionally introduce new allergens but developers and regulators take steps to assess allergenicity of novel proteins. However it is also possible to reduce allergenicity of foods by determining which proteins are responsible for the allergic reaction and then to alter them so that they no longer trigger an immune response in sensitive individuals. While it may not be possible to alter all of the allergenic proteins in some foods, there is potential to open up a whole new range of foods for those who cannot consume them now

Threshold Dose for Shrimp: A Risk Characterization Based on Objective Reactions in Clinical Studies

A DBPCFC [double-blind, placebo-controlled food challenge] of shrimp-allergic adults was conducted to obtain individual threshold doses. Results of this study and published research were combined and a population threshold for shrimp was determined from dose-distribution modeling. The shrimp-allergic population seems to have a higher threshold compared to other populations for other food allergens. Additional shrimp challenges should be done to confirm these initial results

An adjuvant free mouse model of oral allergenic sensitization to rice seeds protein

<p>Abstract</p> <p>Background</p> <p>Rice is commonly known as a staple crop consumed worldwide, though with several rice proteins being reported for allergic properties in clinical studies. Thus, there is a growing need for the development of an animal model to better understand the allergenicity of rice proteins and the immunological and pathophysiological mechanisms underlying the development of food allergy.</p> <p>Methods</p> <p>Groups of BALB/c mice were sensitized daily with freshly homogenized rice flour (30 mg or 80 mg) without adjuvant by intragastric gavage. In addition, the mice were challenged with extracted rice flour proteins at several time points intragastrically. Hypersensitivity symptoms in mice were evaluated according to a scoring system. Vascular leakage, ELISA of rice protein-specific IgE, histopathology of small intestine, and passive cutaneous anaphylaxis were conducted on challenged mice.</p> <p>Results</p> <p>An adjuvant free mouse model of rice allergy was established with sensitized mice showing increased scratching behaviors and increased vascular permeability. Rice protein-specific IgE was detected after eighteen days of sensitization and from the fifth challenge onwards. Inflammatory damage to the epithelium in the small intestine of mice was observed beyond one month of sensitization. Passive cutaneous anaphylaxis results confirmed the positive rice allergy in the mouse model.</p> <p>Conclusions</p> <p>We introduced a BALB/c mouse model of rice allergy with simple oral sensitization without the use of adjuvant. This model would serve as a useful tool for further analysis on the immunopathogenic mechanisms of the various rice allergens, for the evaluation of the hypersensitivity of rice or other cereal grains, and to serve as a platform for the development of immunotherapies against rice allergens.</p

AglH, a thermophilic UDP‑<i>N</i>‑acetylglucosamine‑1‑phosphate:dolichyl phosphate GlcNAc‑1‑phosphotransferase initiating protein<i> N</i>‑glycosylation pathway in <i>Sulfolobus acidocaldarius</i>, is capable of complementing the eukaryal Alg7

AglH, a predicted UDP-GlcNAc-1-phosphate:dolichyl phosphate GlcNAc-1-phosphotransferase, is initiating the protein N-glycosylation pathway in the thermoacidophilic crenarchaeon Sulfolobus acidocaldarius. AglH successfully replaced the endogenous GlcNAc-1-phosphotransferase activity of Alg7 in a conditional lethal Saccharomyces cerevisiae strain, in which the first step of the eukaryal protein N-glycosylation process was repressed. This study is one of the few examples of cross-domain complementation demonstrating a conserved polyprenyl phosphate transferase reaction within the eukaryal and archaeal domain like it was demonstrated for Methanococcus voltae (Shams-Eldin et al. 2008). The topology prediction and the alignment of the AglH membrane protein with GlcNAc-1-phosphotransferases from the three domains of life show significant conservation of amino acids within the different proposed cytoplasmic loops. Alanine mutations of selected conserved amino acids in the putative cytoplasmic loops II (D(100)), IV (F(220)) and V (F(264)) demonstrated the importance of these amino acids for cross-domain AlgH activity in in vitro complementation assays in S. cerevisiae. Furthermore, antibiotic treatment interfering directly with the activity of dolichyl phosphate GlcNAc-1-phosphotransferases confirmed the essentiality of N-glycosylation for cell survival

Agricultural biotechnology and the poor : proceedings of an international conference, Washington, D.C., 21-22 October 1999. Potential health risks of genetically modified organisms: how can allergens be assessed and minimized?

Chapter "Potential health risks of genetically modified organisms: how can allergens be assessed and minimized?" from "Agricultural biotechnology and the poor : proceedings of an international conference, Washington, D.C., 21-22 October 1999"

Prevalence of crab asthma in crab plant workers in Newfoundland and Labrador

Objectives. The aim of the study was to determine the prevalence of snow crab sensitisation and occupational asthma. Study design. Prevalence study of symptoms, pulmonary function testing and allergy testing to crab was conducted in four crab plants of different design in Newfoundland and Labrador, Canada. Methods. Plants workers in four crab plants were interviewed and offered skin testing, RAST, pulmonary function testing and peak flow monitoring before and during crab processing. Results. 38% (n=78) had atopy. 18% (n=39) had certain or highly probable crab asthma. The prevalence of sensitisation in different crab plants varied from 50% (n=19) to 15% (n=16) and the prevalence of certain or highly probable crab asthma varied from 50% (n=19) to 9% (n=3). Conclusion. Crab asthma and sensitisation to snow crab is a major health problem for snow crab plant workers in Newfoundland and Labrado

Snow crab allergy and asthma among Greenlandic workers &#x2013; a pilot study

Objectives. To study snow crab sensitization, occupational allergy and asthma in the snow crab industry in Greenland, as high rates have been found in Canada, but no reports have emerged from the same industry in Greenland. Study design. Pilot survey. Methods. Twenty workers (19 of Inuit and 1 of other origin) in a snow crab (Chionoecetes opilio) and Atlantic shrimp (Pandalus borealis) processing plant in Greenland were assessed with skin prick tests (SPTs) with common aeroallergens and specific allergens from snow crab and shrimp extracts, spirometry, blood sampling for total IgE and specific IgE determination. Eighteen workers contributed a questionnaire-based medical interview. Results. Positive skin prick test reactions were common to snow crab (40%) and shrimp (20%). Specific IgE to snow crab were positive in 4 workers (21%). Two workers had elevated total IgE levels. Symptoms suggestive of asthma were common (45%). Work-related symptoms of skin rash, rhinitis, and/or conjunctivitis were reported by 50%, and symptoms from the lower airways by 39%. Combining history of work-related symptoms with results from specific SPTs and/or specific IgE determination suggested that 11 and 22% of workers suffered from probable and possible occupational asthma, respectively, whereas 22% had possible occupational dermatitis or rhinitis. Conclusions. Greenlander Inuit do not appear to be protected against sensitization to snow crab or shrimp when occupationally exposed to these. This pilot study suggests that occupational allergy and asthma may be as common a problem in Greenlandic workers as in Canadian

Threshold Dose for Shrimp: A Risk Characterization Based On Objective Reactions in Clinical Studies

A DBPCFC [double-blind, placebo-controlled food challenge] of shrimp-allergic adults was conducted to obtain individual threshold doses. Results of this study and published research were combined and a population threshold for shrimp was determined from dose-distribution modeling. The shrimp-allergic population seems to have a higher threshold compared to other populations for other food allergens. Additional shrimp challenges should be done to confirm these initial results