[ evaluation of probiotic effect of L.acidophilus on the immune responses in BALB/C mice against transplanted tumor derived from breast tissue]

Antitumor effect of lactic acid bacteria have been shown in many studies, this effect maybe due to the immunomodulatory properties of these bacteria. In present work we have studied the effect of Lactobacillus [L] acidophilus on the immune responses of BALB/c mice against transplanted tumor derived from breast tissue. 6-8 week-old in-bred BALB/c mice, each weighing 25-30 g, were used. The mice were divided into two groups each consisted of 9 mice as test and control groups. The L.acidophilus ATCC4356 strain was used in this study. It was inoculated in MRS agar and cultivated overnight under anaerobic conditions then collected and resuspended in PBS. After preparation of proper amount of this suspension it was orally [2.7 x 10[8] CFU/ml] administered to the mice with a gastric feeding 2 weeks before tumor transplantation and 3 weeks after that, with 3 days break and 7 days administration. The control mice received an equal volume of PBS during the study. Results of the present work showed that L. acidophilus can increase the production of immunomodulatory cytokine IL-12 and decrease the TGF-alpha which can suppress immune response. Moreover, the growth rate of tumor in group which received L. acidophilus were decreased and the results of delayed type hypersensitivity [DTH] of this group in 48h were better than control group. The results of our study suggest that daily use of L. acidophilus can regulate immune response with Th1 dominance and may be helpful for cancer immunotherapy, but further studies are needed to investigate the other mechanisms of this effect

[ probiotic effects of Lactobacillus casei in BALB/c mice on the Tumor growth rate bearing breast cancer]

Antitumor effect of lactic acid bacteria [LAB] have been shown in many studies, this effect maybe as a result of immunomodulatory properties of these bacteria. In present work, we have studied the effect of Lactobacillus casei on the tumour growth rate in BALB/c mices bearing breast cancer. 6-8 week-old In-bred BALB/c mice, each weighing 25-30 g, were used. There are two experimental group consisted of 9 mices that they were used as controls in each assay. The L.casei ATCCT 39392 strain used in this study was inoculated in MRS broth and cultivated for a day at 37 °C under anaerobic conditions, collected by centrifugation and resuspend in PBS. After preparation of proper amount of these suspension it was orally administered to the mice with a gastric feeding, Control mice received an equal volume of PBS in duration of study. Results of this study showed that oral administration of L.casei can inhibit the tumour growth and increased the local inflammation in DTH assay as a result of increase in immune responses efficiency. In conclusion oral administration of Lactobacillus casei may regulate immune responses skewed Th1 balance and maybe helpful for cancer immunotherapy, but further studies is needed to investigate the other mechanisms of this effect