Immunomodulatory properties of the milk whey products obtained by enzymatic and microbial hydrolysis

P>The objective of this study was to investigate the in vitro immunomodulatory effect of milk whey through enzymatic hydrolysis, microbial fermentation and two-stage hydrolytic reactions (enzymatic and microbial reactions) by analysing cytokine profiles. Results indicated that the milk whey sample fermented by Lactobacillus kefiranofaciens M1 and two-stage hydrolytic reactions (hydrolysed by Alcalase and then fermented by L. kefiranofaciens M1) could significantly induce the production of tumour necrosis factor (TNF)-alpha and IL-12 compared with the milk whey control and enzymatic treatments. Further characterisation of the immunomodulatory factor by membrane filtration and mutanolysin hydrolysation, the stimulatory activity for IL-12 and TNF-alpha production was found to be reduced and to be correlated positively with the cell wall components in L. kefiranofaciens M1. In addition, Th2-polarised splenocytes revealed that L. kefiranofaciens M1 had both IL-12 inducing and IL-4 repressing activities. These results suggested that L. kefiranofaciens M1 could direct the Th1/Th2 balance toward Th1.