Immunoregulatory peptides in bovine milk

Bovine milk is known to contain a number of peptide fractions that can affe ct immune function. The vast majority of immunoregulatory peptides that hav e been characterised are hydrolysate derivatives of major milk proteins. Re cent research has also indicated that the metabolic activity of probiotic l actic acid bacteria can generate de novo immunoregulatory peptides from mil k, via enzymatic degradation of parent milk protein molecules. In contrast, relatively little is known of endogenous, preformed immunoregulatory pepti des in milk that may be relevant to modulating human health. The natural in vivo role of preformed and enzymatically derived peptides is likely to be one of regulation of the neonatal (bovine) gastrointestinal tract immune sy stem, in order to modulate immune function with respect to the development of immunocompetence and avoidance of undesirable immunological responses (e .g. tolerance, and hypersensitivity to nutrients). There is scope for the f urther characterisation of both the origin and function of milk-derived imm unoregulatory peptides, so that their potential to influence human health c an he fully appraised. This review highlights our current knowledge of milk -derived immunoregulatory peptides, and outlines areas that are of relevanc e for further research.