Immune-stimulating effects of lactic acid bacteria in vivo and in vitro
Immune-stimulating effects of lactic acid bacteria in vivo and in vitro
复制标题
DOI：
10.1017/s0029665110001710
复制
发表时间：
2010-08-01
影响因子：
7
通讯作者：
Meyer, Alexa L.
中科院分区：
文献类型：
--
作者：
Elmadfa, Ibrahim;Klein, Petra;Meyer, Alexa L.
乳酸菌（LAB）的健康促进作用得到了广泛认可，使其成为受欢迎的功能性食品成分。市售益生菌产品通常被宣传为也能够改善健康受试者的免疫防御。然而，虽然乳酸菌的效果存在菌株特异性差异，但传统酸奶细菌也被证明是有益的。为了比较常规和益生菌LAB的免疫效果，年轻健康女性接受市售益生菌发酵乳制品或常规酸奶四周。两种治疗均显示出相当的效果，导致对刺激物的免疫反应更强（对癌细胞的天然细胞毒性、促分裂原诱导的T淋巴细胞活化和刺激的细胞因子产生）。为了研究这些作用背后的机制，在细胞水平上对常规（德氏乳杆菌）和益生菌（鼠李糖乳杆菌GO）、LAB进行了体外比较。有趣的是，L. rhamnosusGG在诱导树突状细胞（DC）成熟方面更有效，所述树突状细胞在指导对刺激的免疫应答中起实质性作用。反过来，L. delbrueckii引起促炎细胞因子以及IL-10的更高分泌。然而，这些作用仅在DC和LAB直接孵育后观察到，而不是在两者被肠细胞样Caco-2细胞层分开时观察到。LAB还以类似的方式诱导外周血单核细胞中的细胞因子分泌，并且这种作用在Caco-2细胞模型中降低，表明肠道上皮细胞的调节影响。虽然传统和益生菌菌株都能调节免疫反应，但特定的特性可能为某些疾病的治疗提供治疗选择。
The health-promoting effects of lactic acid bacteria (LAB) are well recognised, making them a popular functional food ingredient. Commercially available probiotic products are often promoted as capable of improving immune defences also in healthy subjects. However, while strain-specific differences exist in the effects of LAB, conventional yoghurt bacteria have proved beneficial as well. For comparing the immunological effects of conventional and probiotic LAB, young healthy women received either a commercially available probiotic fermented milk product or a conventional yoghurt for four weeks. Both treatments showed comparable effects resulting in a stronger immunological reaction to stimuli (natural cytotoxicity against cancer cells, mitogen-induced T-lymphocyte activation and stimulated cytokine production). To study the mechanisms behind these effects, conventional (Lactobacillus delbrueckii) and probiotic (Lactobacillus rhamnosus GO), LAB were compared in vitro at the cellular level. Interestingly, L. rhamnosus GG was more potent in inducing maturation of dendritic cells (DC) that play a substantial role in directing the immune response to stimuli. In turn, L. delbrueckii provoked a higher secretion of proinflammatory cytokines as well as IL-10. These effects were, however, observed only after direct incubation of DC and LAB, not when both were separated by a layer of enterocyte-like Caco-2 cells. LAB also induced cytokine secretion in peripheral blood mononuclear cells in a similar manner and this effect was reduced in a Caco-2 cell model, suggesting a modulating influence of gut epithelial cells. While both conventional and probiotic strains modulate the immune response, specific properties may offer therapeutic options in the treatment of certain diseases.