Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 13 4 2014 08 15 231 239 EN Cuicui Duan Key Laboratory of Dairy Science, Ministry of Education, Northeast Agricultural University, Harbin 150030, China. Lijie Yang Key Laboratory of Dairy Science, Ministry of Education, Northeast Agricultural University, Harbin 150030, China. Aili Li Key Laboratory of Dairy Science, Ministry of Education, Northeast Agricultural University, Harbin 150030, China. Rui Zhao Key Laboratory of Dairy Science, Ministry of Education, Northeast Agricultural University, Harbin 150030, China. Gui-Cheng Huo Key Laboratory of Dairy Science, Ministry of Education, Northeast Agricultural University, Harbin 150030, China. 2015 10 16 Cow’s milk whey consists of many protein components and some of them are antigens to human and known to modulate immune responses. Enzymatic hydrolysis is a useful method to modify proteins with allergenicity. The objective of this study was to identify whether the in vitro enzymatic hydrolysis could reduce the allergenicity of whey protein concentrates (WPC). In  this study, WPC were hydrolyzed by trypsin and twenty-four BALB/c mice were divided into three groups and fed with WPC formula and WPC hydrolysates formula, while the control mice received milk-free diet. The results revealed that there was no significant difference between the body weights among all groups. WPC-fed mice produced an elevated spleen lymphocyte proliferation level than WPC hydrolysates-fed mice and also produced higher levels of WPC-specific IgE in intestinal tract and serum in comparison to WPC hydrolysates-fed mice and control group. Significant up-regulation of plasma histamine levels were also observed and showed the same trend with IgE. The secretions of IL-4 and IL-5 were significantly enhanced by WPC. WPC significantly suppressed  the  secretion of  IFN-γ  while hydrolysates of  WPC significantly increased the secretion of IFN-γ compared to control group. These results suggest that hydrolysis may play a role to reduce the allergenicity of WPC. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/451 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/451/386