Interactions between dietary proteins and the human system: implications for oral tolerance and food-related diseases.

Mounting evidence suggests that there are a number of important, but poorly understand, interactions between dietary proteins and the human immune system. The usual response of the human immune system to dietary proteins seems to be that of oral tolerance, a phenomenon involving up-regulation of protective gut localized immune mechanisms and down-regulation of potentially harmful systemic immunity to the protein in question. Abrogation of oral tolerance may play an important role in the development of food allergies and food enteropathies. Immune mechanisms underlying oral tolerance are therefore discussed in light of current understanding of such food-related diseases as IgE mediated food allergies and gluten sensitive enteropathy. Possible development of oral vaccines to immune-related diseases like multiple sclerosis and rheumatoid arthritis is also discussed.