Ya Tuo, Zhang Qijin, Chu Fuliang, Merritt Justin, Bilige Menhe, Sun Tiansong, Du Ruiting, Zhang Heping
The Key Laboratory of Dairy Biotechnology and Bioengineering, Education Ministry of PR China, Department of Food Science and Engineering, Inner Mongolia Agricultural University, Huhhot, PR China.
BMC Immunol. 2008 Nov 19;9:68. doi: 10.1186/1471-2172-9-68.
There is increasing evidence to suggest an immunomodulation function both within the intestines and systemically upon consuming probiotic species. We recently isolated a novel LAB, Lactobacillus caseiZhang (LcZhang) from koumiss. LcZhang exhibited favorable probiotic properties, such as acid resistance, bile resistance, gastrointestinal (GI) colonization ability, etc. In order to examine the immunomodulatory qualities of LcZhang, we administered LcZhang to healthy mice with varying doses of either live or heat-killed LcZhang and measured various parameters of the host immune response.
The study was performed in four separate experiments via oral administration of live and heat-killed LcZhang to BALB/c mice for several consecutive days. We investigated the immunomodulating capacity of LcZhang in vivo by analyzing the profile of cytokines, T cell subpopulations, and immunoglobulin concentrations induced in blood serum and intestinal fluid in BALB/c mice. Only live bacteria elicited a wide range of immune responses, which include the increased production of interferon-gamma (IFN-gamma), and depression of tumor necrosis factor-alpha (TNF-alpha) levels. In addition, interleukin-2 (IL-2) and IL-2 receptor gene transcription increased significantly, but the proportion of T cell subsets appeared to be unaffected. We also observed that LcZhang was capable of inducing gut mucosal responses by enhancing the production of secretory Immunoglobulin A (sIgA) as well influencing the systemic immunity via the cytokines released to the circulating blood.
The present work shows that the dose-dependent administration of LcZhang is capable of influencing immune responses, implying that it may be a valuable strain for probiotic use in humans.
越来越多的证据表明，食用益生菌后，肠道内和全身都会产生免疫调节功能。我们最近从马奶酒中分离出一种新型乳酸菌——干酪乳杆菌Zhang（LcZhang）。LcZhang具有良好的益生菌特性，如耐酸性、耐胆汁性、胃肠道（GI）定植能力等。为了研究LcZhang的免疫调节特性，我们给健康小鼠施用不同剂量的活的或热灭活的LcZhang，并测量宿主免疫反应的各种参数。
该研究通过连续数天给BALB/c小鼠口服活的和热灭活的LcZhang，在四个独立的实验中进行。我们通过分析BALB/c小鼠血清和肠液中诱导的细胞因子谱、T细胞亚群和免疫球蛋白浓度，研究了LcZhang在体内的免疫调节能力。只有活细菌引发了广泛的免疫反应，包括干扰素-γ（IFN-γ）产量增加和肿瘤坏死因子-α（TNF-α）水平降低。此外，白细胞介素-2（IL-2）和IL-2受体基因转录显著增加，但T细胞亚群的比例似乎未受影响。我们还观察到，LcZhang能够通过增强分泌型免疫球蛋白A（sIgA）的产生来诱导肠道黏膜反应，并通过释放到循环血液中的细胞因子影响全身免疫。
目前的研究表明，剂量依赖性施用LcZhang能够影响免疫反应，这意味着它可能是一种有价值的益生菌菌株，可用于人类。
