Department of Microbiology, School of Public Health and Institute of Health Researches, Tehran University of Medical Sciences, PO Box 14155-6446, Tehran, Iran.
Br J Nutr. 2010 Jul;104(2):227-32. doi: 10.1017/S0007114510000516. Epub 2010 Mar 2.
Lactic acid bacteria can affect the maturation of immune cells and their products not only in the gut but also on the systemic immune organs such as lymph nodes and spleen. In the present work, we studied the effects of oral administration of Lactobacillus acidophilus on the immune responses of BALB/c mice bearing transplanted breast tumour. Two groups of female inbred BALB/c mice, each containing nine mice as test and control, were used. The L. acidophilus ATCC4356 strain was inoculated in DeMan-Rogosa-Sharpe broth and cultivated for 24 h at 37 degrees C. Then, it was collected by centrifugation, and was washed and suspended in PBS. Afterwards, 0.5 ml/d of this suspension, which contained 2.7 x 108 colony forming units/ml of bacteria, was orally administered to the mice by gavage, 14 d before tumour transplantation and 30 d after that with 3-d intervals. Similar to the test mice, the control mice received an equal volume of PBS. The results showed that oral administration of L. acidophilus increased the production of IL-12 (P < 0.05) and decreased the level of transforming growth factor beta (P = 0.05) in the splenocyte culture. Moreover, the growth rate of tumour in the test mice decreased (P < 0.01), and the results of delayed-type hypersensitivity assay after 48 h were risen (P < 0.05) in comparison with the controls. Results suggest that daily consumption of L. acidophilus can improve the production of immunomodulatory cytokine IL-12 in the splenocyte culture, which was stimulated by tumour antigen in BALB/c mice bearing transplanted breast tumour. But further studies are needed to find out some other possible mechanisms of this effect.
乳酸菌不仅可以影响肠道中的免疫细胞及其产物的成熟，还可以影响淋巴结和脾脏等全身免疫器官中的免疫细胞及其产物的成熟。在本研究中，我们研究了嗜酸乳杆菌口服给药对携带移植性乳腺癌的 BALB/c 小鼠免疫应答的影响。使用两组雌性近交系 BALB/c 小鼠，每组 9 只作为实验组和对照组。将嗜酸乳杆菌 ATCC4356 菌株接种于德氏乳杆菌-沙氏培养基中，在 37°C 下培养 24 小时。然后通过离心收集，并用 PBS 洗涤和悬浮。之后，通过灌胃向小鼠口服 0.5ml/d 的悬浮液，其中含有 2.7×108 个菌落形成单位/ml 的细菌，在肿瘤移植前 14 天和移植后 30 天，每隔 3 天进行一次。与实验组小鼠相似，对照组小鼠接受等量的 PBS。结果表明，嗜酸乳杆菌的口服给药增加了脾细胞培养物中 IL-12 的产生（P<0.05），降低了转化生长因子-β的水平（P=0.05）。此外，实验组小鼠肿瘤的生长速度降低（P<0.01），与对照组相比，48 小时后迟发型超敏反应试验的结果升高（P<0.05）。结果表明，每天食用嗜酸乳杆菌可以改善携带移植性乳腺癌的 BALB/c 小鼠脾细胞培养物中免疫调节细胞因子 IL-12 的产生，而这种作用可能与肿瘤抗原刺激有关。但是，需要进一步的研究来发现这种作用的其他可能机制。
