Enhancement of Mucosal Antibody Responses by Dietary Whey Protein Concentrate

Abstract

The effect of dietary bovine whey protein concentrate (WPC) on gut mucosal antibody responses to orally-administered antigens was investigated in BALB/c mice. Test mice were fed a diet containing 20% (w/w) total protein of a novel WPC (ALACEN 472) for 12 weeks. Test and control (chow-fed) mice were immunized orally with cholera toxin (CT) and ovalbumin (OVA) at different times throughout the dietary regime, and gut mucosal antibody responses were assessed at the end of the experiment. Both groups of mice produced mucosal antibodies against CT and OVA, although responses were significantly higher among WPC-fed mice, regardless of the time-point at which immunizations were administered throughout the study. WPC had no significant effect on blood lymphocyte phenotype expression or splenic T or B cell mitogenesis, suggesting that the immunomodulatory action was not due to systemic lymphocyte activation. This study confirms previous reports that dietary WPC can potentiate humoral immunity in mice, and provides the first evidence that WPC can enhance mucosal antibody responses to orally-administered antigens.