Immunoendocrinology, Division of Medical Biology, Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
Department of Obstetrics and Gynaecology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
Mol Nutr Food Res. 2017 Oct;61(10). doi: 10.1002/mnfr.201700171. Epub 2017 Jul 20.
In vivo studies demonstrating that only specific dietary-fibers contribute to immunity are still inconclusive, as measuring immune effects in healthy humans remains difficult. We applied a relatively inefficacious vaccination-challenge to study chain length-dependent effects of inulin-type fructan (ITF) dietary fibers on human immunity.
ITFs with two different 'degree of polymerization-' (DP)-profiles were tested in vitro for effects on PBMC-cytokines and TLR2 activation. In a double-blind placebo-controlled trial, 40 healthy volunteers (18-29 years) were divided into three groups and supplemented from day 1 to day 14 with DP10-60 ITF, DP2-25 ITF (both n = 13), or fructose placebo (n = 14), 8 g/day. On day 7, all volunteers were vaccinated against hepatitis B. Anti-HbsAg-titer development and lymphocyte subsets were studied. In vitro, DP10-60 ITFs stimulated a Th1-like cytokine profile and stimulated TLR2 more strongly than DP2-25 ITFs. In vivo, DP10-60 increased anti-HBsAg titers, Th1-cells, and transitional B-cells. Both ITFs increased CD45RO CTLs at day 35, and CD161 cytokine producing NK-cells at day 21 and 35.
Support of immunity is determined by the chain length of ITFs. Only long-chain ITFs support immunity against pathogenic hepB-epitopes introduced by vaccination. Our findings demonstrate that specific dietary fibers need to be selected for immunity support.
体内研究表明，只有特定的膳食纤维对免疫有贡献，但仍没有定论，因为在健康人群中测量免疫效果仍然很困难。我们应用一种相对低效的疫苗接种挑战来研究菊粉型果聚糖（ITF）膳食纤维对人体免疫的链长依赖性影响。
体外测试了两种不同“聚合度”（DP）-谱的 ITF 对 PBMC-细胞因子和 TLR2 激活的影响。在一项双盲安慰剂对照试验中，40 名健康志愿者（18-29 岁）分为三组，从第 1 天到第 14 天每天补充 DP10-60 ITF、DP2-25 ITF（每组 n = 13）或果糖安慰剂（n = 14），剂量为 8 g/天。第 7 天，所有志愿者接种乙型肝炎疫苗。研究了抗-HbsAg 滴度的发展和淋巴细胞亚群。体外，DP10-60 ITF 刺激产生 Th1 样细胞因子谱，并比 DP2-25 ITF 更强地刺激 TLR2。体内，DP10-60 增加了抗-HBsAg 滴度、Th1 细胞和过渡 B 细胞。两种 ITF 均在第 35 天增加 CD45RO CTL，在第 21 天和第 35 天增加 CD161 细胞因子产生 NK 细胞。
免疫支持取决于 ITF 的链长。只有长链 ITF 支持针对疫苗接种引入的致病 HepB-表位的免疫。我们的研究结果表明，需要选择特定的膳食纤维来支持免疫。
