Induction of oral tolerance to cow's milk proteins in rats fed with a whey protein hydrolysate

Abstract

Animal models have shown that oral administration of an antigen induces a specific immunologic tolerance to this antigen. Induction of such an oral tolerance has been well documented with intact proteins. The purpose of our study was to determine whether oral tolerance to cow's milk proteins (CMP) can be induced also with protein peptides contained in either partially hydrolysed or extensively hydrolysed cow's milk formulas. Five-week-old Sprague-Dawley rats were fed cow's milk formulas ad libitum before they were parenterally challenged with CMP. The modulation of specific IgE anti-CMP antibodies and intestinal mast cell stimulation were measured. Results showed that preventive feeding of rats with a partially hydrolysed cow's milk formula suppresses specific IgE anti-CMP antibodies as well as IgE mediated mediator release (rat mast cell protease RMCPII) from intestinal mast cells. An extensively hydrolysed cow's milk formula was unable to achieve the induction of such an oral tolerance. Our experiments show that selected peptides of CMP may induce a specific oral tolerance to CMP.