Improved ELISA method for screening human antigen-specific IgE and its application for monitoring specific IgE for novel proteins in genetically modified foods

2015 Evidence Analysis Library Systematic Review on Advanced Technology in Food Production

In the late 20th century, plant breeders began using molecular biology techniques such as recombinant DNA, also known as genetic engineering, along with traditional cross-breeding. Ten plant and one animal food have been approved for commercialization in the United States. Today, foods and ingredients from genetically engineered (GE) crops are present throughout the food supply, which has led to varying levels of acceptance. Much discussion exists among consumers and health professionals about the believability of statements made regarding benefits or risks of GE foods. The aim of this systematic review was to examine the evidence on the association of consumption of GE foods and ingredients derived from them on human health, specifically allergenicity, food safety, pesticide consumption, nutrient adequacy, inflammation, and antibiotic resistance. An expert panel conducted a systematic review on advanced technology in food production. The 30 developed questions focused on effects of human consumption of GE foods and the effects of human consumption of foods containing pesticide residues on human health. Primary research published from 1994 to 2014 were identified using PubMed and Agricultural Online Access databases. Additional studies were identified by searching references of review articles. Twenty-one studies met the inclusion criteria. Relevant research addressed five of 30 questions. Four questions focused on food allergenicity, the fifth on nutrient adequacy, and all received a Grade III (limited/weak) rating. No human studies addressed 25 questions on the consumption of foods produced using genetic engineering technologies on gene translocation, cancer, food safety, phenotype expression, inflammation and inflammatory markers, or antibiotic resistance. These questions received a Grade V (grade not assignable). Evidence from human studies did not reveal an association between adverse health effects and consumption of foods produced using genetic engineering technologies. Although the number of available human studies is small, they support that there are no clear adverse health effects-as they relate to allergenicity and nutrient adequacy-associated with consumption of GE foods. The present systematic review is aligned with a recent report by the National Academy of Sciences that included human and animal research.

ELISA method for monitoring human serum IgE specific for Cry1Ab introduced into genetically modified corn

Enzyme-linked immunosorbent assay (ELISA) is the most convenient method of monitoring the occurrence of IgE antibodies specific for novel proteins in genetically modified (GM) foods. The levels of IgE specific for a recombinant protein, Cry1Ab, were determined using an ELISA method. A soluble form of the Cry1Ab protein purified from pCold1 vector-transformed Escherichia coli pTf16/BL21 was used as the ELISA coating antigen, and 1M NaCl was used as the washing buffer to remove IgE non-specifically bound to the coated antigen. Sera from 44 patients allergic to major food allergens were obtained, diluted 20-fold, tested, and found no identifiable IgE above background levels. We also tested sera from patients with corn allergy against whole extracts of non-GM and GM-corn (MON 810) using immunoblotting. The staining patterns were similar for the two types of corn. These results indicate that significant levels of IgE antibodies specific to Cry1Ab were not found in the sera of Japanese patients with food allergies.