DuPont Nutrition and Health, Active Nutrition, Sokeritehtaantie 20, 02460 Kantvik, Finland.
Department of Health, NIZO Food Research, PO Box 20, 6710 BA Ede, The Netherlands.
Br J Nutr. 2014 Feb;111(3):465-73. doi: 10.1017/S0007114513002547. Epub 2013 Aug 12.
To assess the effect of Lactobacillus acidophilus (American Type Culture Collection (ATCC) 700396) on enterotoxigenic Escherichia coli (ETEC) infection, in the present study, a parallel, double-blind, placebo-controlled 4-week intervention was performed in healthy males. The subjects largely consumed their habitual diet, but had to abstain from consuming dairy foods generally high in Ca. The subjects were randomised into the L. acidophilus (dose 10⁹ colony-forming units twice daily; n 20) or the placebo (n 19) group. After an adaptation period of 2 weeks, the subjects were orally infected with a live, but attenuated, ETEC vaccine, able to induce mild, short-lived symptoms. Before and after the challenge, the subjects recorded stool consistency, bowel habits, and frequency and severity of gastrointestinal complaints. The ETEC challenge led to a significant increase in faecal output on the 2nd day and a concomitant increase in Bristol stool scale scores. Likewise, abdominal pain, bloating, flatulence, fever, headache and nausea peaked 1 d after the oral challenge. The concentrations of faecal calprotectin and IgA peaked 2 d after and that of serum IgM peaked 9 and 15 d after the oral challenge. The concentrations of serum IgA and IgG were unaffected. The ETEC challenge led to a reduction in the number of Bacteroides-Prevotella, Bifidobacterium, Clostridium cluster XIVab and total faecal bacteria. Probiotic treatment was associated with a larger increase in Bristol stool scale scores and more fever, headache and nausea after the ETEC challenge compared with the placebo treatment. These differences were, however, small and with substantial variation within the groups. Oral application of an attenuated live ETEC vaccine provides a useful model for food-borne infections. Supplementation with L. acidophilus ATCC 700396, however, was ineffective in reducing ETEC infection symptoms in healthy men.
为了评估嗜酸乳杆菌（美国典型培养物保藏中心（ATCC）700396）对肠产毒性大肠杆菌（ETEC）感染的影响，本研究在健康男性中进行了一项平行、双盲、安慰剂对照的 4 周干预。受试者主要食用他们习惯的饮食，但必须避免食用通常富含 Ca 的乳制品。受试者被随机分为嗜酸乳杆菌（剂量 10⁹ 菌落形成单位，每日两次；n=20）或安慰剂（n=19）组。经过 2 周的适应期后，受试者口服了一种活但减毒的 ETEC 疫苗，该疫苗能够引起轻微的、短暂的症状。在挑战前后，受试者记录了粪便稠度、排便习惯以及胃肠道不适的频率和严重程度。ETEC 挑战导致第 2 天粪便排出量显著增加，同时布里斯托粪便量表评分升高。同样，腹痛、腹胀、气胀、发热、头痛和恶心在口服挑战后 1 天达到峰值。粪便钙卫蛋白和 IgA 的浓度在口服挑战后 2 天达到峰值，血清 IgM 的浓度在口服挑战后 9 天和 15 天达到峰值。血清 IgA 和 IgG 的浓度不受影响。ETEC 挑战导致双歧杆菌、拟杆菌、梭菌簇 XIVab 和总粪便细菌数量减少。与安慰剂治疗相比，益生菌治疗后 ETEC 挑战后布里斯托粪便量表评分升高更多，发热、头痛和恶心更多。然而，这些差异很小，且组内差异很大。口服应用减毒活 ETEC 疫苗提供了一种有用的食源性感染模型。然而，补充嗜酸乳杆菌 ATCC 700396 并不能有效减轻健康男性的 ETEC 感染症状。
