Shimada T, Cheng L, Shi H B, Hayashi A, Motonaga C, Tang J, Enomoto K, Enomoto T
Central Research Laboratories, Nichinichi Pharmaceutical Co Ltd, Mie, Japan.
J Investig Allergol Clin Immunol. 2007;17(2):70-6.
Recent epidemiological studies have indicated that early life receipt of antibiotics may be associated with an increased risk of developing atopic disorder. Lysed Enterococcus faecalis FK-23 (LFK), a probiotic product of E faecalis, has been shown to have inhibitory effects on allergen-induced immune responses in mice.
The purpose of this study was to evaluate the effects of LFK on immune responses and intestinal microflora in antibiotic-treated, and allergen-sensitized weaning mice.
Three-week-old BALB/c mice were sensitized with cedar pollen allergen to establish the experimental model. The allergen-induced peritoneal accumulation of eosinophils, serum levels of total and allergen-specific immunoglobulin (Ig) E and IgG2a, and the intestinal bacterial flora were determined in the control, antibiotic, LFK and antibiotic-LFK groups (n = 7 in all groups). Orally administered erythromycin, one kind of macrolide antibiotic, was used for the experiments.
There was no significant difference in the allergen-induced peritoneal accumulation of eosinophils and serum specific IgE and IgG2a levels in erythromycin-treated mice compared to a control group. However, the ratio of serum total IgE to IgG2a levels was significantly increased in erythromycin-treated mice relative to that found either in LFK-treated mice or in erythromycin-treated mice with LFK supplementation. The total aerobes, total anaerobes and Enterococcus species of intestinal microflora were not significantly different among all groups. Lactobacillus species were distinctly eliminated in the mice exposed to erythromycin on day 7 and totally recovered in erythromycin-treated mice with LFK intervention on day 28, but could not be recovered in the erythromycin-treated mice without LFK intervention.
Our results suggest that LFK may improve the intestinal ecosystem disturbed by antibiotic use, and thereby prevent subsequent development of atopy. However, whether different antibiotics have different effects on immune responses needs to be addressed further.
近期的流行病学研究表明，生命早期接受抗生素治疗可能会增加患特应性疾病的风险。粪肠球菌FK-23裂解物（LFK）是粪肠球菌的一种益生菌产品，已被证明对小鼠过敏原诱导的免疫反应具有抑制作用。
本研究旨在评估LFK对经抗生素治疗且对过敏原致敏的断奶小鼠免疫反应和肠道微生物群的影响。
用雪松花粉过敏原致敏3周龄的BALB/c小鼠以建立实验模型。在对照组、抗生素组、LFK组和抗生素-LFK组（每组n = 7）中测定过敏原诱导的嗜酸性粒细胞在腹膜中的积聚、血清总免疫球蛋白（Ig）E和过敏原特异性IgE及IgG2a水平，以及肠道细菌菌群。实验使用口服给予的一种大环内酯类抗生素红霉素。
与对照组相比，红霉素治疗的小鼠中，过敏原诱导的嗜酸性粒细胞在腹膜中的积聚以及血清特异性IgE和IgG2a水平没有显著差异。然而，与LFK治疗的小鼠或补充LFK的红霉素治疗的小鼠相比，红霉素治疗的小鼠血清总IgE与IgG2a水平的比值显著升高。所有组之间肠道微生物群的需氧菌总数、厌氧菌总数和肠球菌种类没有显著差异。在第7天暴露于红霉素的小鼠中，乳酸杆菌种类明显减少，在第28天接受LFK干预的红霉素治疗的小鼠中完全恢复，但在未接受LFK干预的红霉素治疗的小鼠中无法恢复。
我们的结果表明，LFK可能改善因使用抗生素而受到干扰的肠道生态系统，从而预防随后特应性疾病的发生。然而，不同抗生素对免疫反应是否有不同影响需要进一步研究。
