Immunomodulatory function of lactic acid bacteria

Using mice, we found that oral administration of Bifidobacterium breve YIT4 064 (B. breve) activated the humoral immune system, augmented anti-rotaviru s IgA production or anti-influenza virus (IFV) IgG production and protected against rotavirus infection or influenza infection, respectively. Furtherm ore, when the B. breve was given to infants from an infant home, there was a significant reduction of the frequency of rotavirus shedding in stool sam ples during the administration of the bacteria. It was also found, again us ing mice, that oral administration of Lactobacillus casei strain Shirota (L cS) stimulated type 1 helper T (Th1) cells, activated the cellular immune s ystem and inhibited incidence of tumors and IgE production. These results d emonstrated that these two strains of lactic acid bacteria modulated the di fferent immune systems each in its own way and prevented against various di seases.