Food Allergy Safety Assessment: An Introduction

Food allergy is a common, important, and probably increasing health problem that currently affects between 1% and 2% of adults and approximately 5% of children in North America and Europe (1). With an increasing interest in the development of novel foods, including those derived from genetically modified crops, some debate has developed about possible sources of adverse health effects and the need for appropriate safety assessment strategies (2–8). A major focus of attention has been the potential for allergenicity, and particularly consideration of whether novel proteins expressed in transgenic plants will be able to induce de novo sensitization and=or elicit allergic reactions in those who are already sensitized (9–14). The need for accurate assessments of the allergenic potential of novel proteins provides toxicologists with some significant, but nevertheless intriguing, challenges. One of the major issues is the basis for differences between proteins with respect to sensitization potential. Although something is known of the physicochemical features that characterize chemical allergens, the properties that confer on proteins the ability to cause allergic sensitization are less well defined (15). Clearly, a more detailed appreciation of the molecular, structural, and functional requirements for the effective induction of sensitization will facilitate new approaches to safety assessment in the future. In the meantime, however, a battery of experimental methods are available that collectively provide a sound basis for the identification and characterization of proteins that have an inherent potential to cause sensitization. The majority of these were included in a decision tree approach to allergenicity assessment that was recommended by a task force of the International Food Biotechnology Council and the Allergy and Immunology Institute of the International Life Sciences Institute (16). This represented the first coherent and systematic strategy for evaluating the sensitizing potential of novel