Effect of exopolysaccharides from Lactobacillus paracasei VL8cooperated with Con A on spleen lymphocyte proliferation and induction of cytokine in mice

The strains of lactobacillus paracasei VL8 was isolated form viili as base as described previously, futher researching of the immunomodulation of VL8-EPS was investigated. Firstly, preparation of mouse spleen lymphocytes and the proliferation of spleen lymphocytes in mice with different concentrations of VL8-EPS were determined by MTT.The contents of IL-2, IFN-γand IL-6 were determined by using ELISA.The results showed that VL8-EPS at a concentration ranging from 12.5 μg/m L to800 μg/m L resulted in a significant increase of spleen lymphocyte proliferation, VL8-EPS could also enhance the effect of Con A-induced spleen lymphocyte proliferation and the induction effects was higher than that of single application of VL8-EPS.Moreover, VL8-EPS could significantly increase the secretion level of IL-2, IFN-γ and IL-6 in Con A-induced spleen lymphocyte. In summary, VL8-EPS can effectively increase spleen lymphocyte proliferation and enhance the effect of Con Ainduced spleen cell growth. VL8-EPS has the ability to enhance immune responses by increasing the secretion of cytokine. It showed that VL8-EPS could regulate the immune mechanisms partly.