The Modulating Effect Of Lactic Acid Bacteria On Immune System

In this research, the mice were fed with the milk suspension(2.0~3.0×1010 cfu/ml) and fermented milk(2.0~3.0×108 cfu/ml) which were made of Lactic Acid Bacteria L.casei zhang and L.acidophilus MG2-1 by different dosages. Use ELISA method to determine IgG content in the blood and SIgA content in the gut at 5th, 10th, 15th, 20th, 25th, 30th intervals, use FCM to determine the T cell CD3+, CD4+,CD8+ in the blood and calculate the change of CD4+/CD8+ ratio. The result showed that: (1) the IgG content in the blood and SIgA content in the gut of the mice which were fed with Lactic Acid Bacteria L. casei.zhang and L.acidophilus MG2-1 were significantly increased compared with the mice which were not fed(p<0.05, p<0.01), and there was also some significant differences between milk suspension groups, fermented milk groups and the different dosages (p<0.05, p<0.01). SIgA and IgG content have the tendency that was increased with time. (2) the proportion of T cell CD3+, CD4+,CD8+ in the blood was increased after fed with the milk suspension and fermented milk which were made of Lactic Acid Bacteria L.casei zhang and L.acidophilus MG2-1, optimize the CD4+/CD8+ ratio (p<0.05, p<0.01).Then we did another research, the chick were fed with milk suspension and fermented milk which were made of Lactic Acid Bacteria L.casei zhang and L.acidophilus MG2-1 by different dosages. The chick were vaccinated with ND two times at 10 days age and 28 days age, then determined the valence of HI antibody at 7th, 14th day after second vaccination. The result showed that compare with CK (did not fed with Lactic Acid Bacteria L.casei zhang and L.acidophilus MG2-1), the antibody level of each experimental group was all reached to significant and extremely significant (p<0.05, p<0.01), and the antibody level was enhanced by 0.61~1.77(log2).