摘要目的 探讨经热处理及酶裂解的肠球菌faecalis FK-23菌株(简称LFK)和经热处理的肠球菌faecium sp.TN-3菌株(简称TN)对实验性变应性鼻炎(allergic rhinitis,AR)的抗变态反应作用.方法 BALB/c小鼠24只完全随机分为4组:阳性对照组、LFK组、TN组、阴性对照组.采用卵清蛋白(ovalbumin,OVA)腹腔注射及鼻腔激发建立AR小鼠模型,阴性对照组以生理盐水代替OVA进行腹腔注射及鼻腔激发.LFK组和TN组分别给予相应的益生菌制品对小鼠进行经口灌胃,每次0.5 ml(60 mg),每日1次,共计42 d；阳性和阴性对照组用生理盐水灌胃处理.观察经灌胃干预后第21、27、35天小鼠搔鼻和喷嚏次数.第42天取小鼠鼻部组织进行HE染色,观察鼻黏膜嗜酸粒细胞的浸润程度.采用酶联免疫吸附试验检测小鼠血清和脾细胞培养液中γ干扰素(interferon,IFN)、白细胞介素(interleukin,IL)4和OVA特异性IgE水平.结果 ①在27 d,LFK组小鼠的搔鼻次数与阳性对照组相比明显减少,差异有统计学意义(=2.95,P=0.028)；在35 d,LFK组、TN组小鼠的搔鼻次数(f值分别为3.75和3.06,P值分别为0.005和0.011)和喷嚏次数(t值分别为2.56和3.35,P值分别为0.038和0.01)均明显减少,与阳性对照组相比差异有统计学意义.②在42 d,小鼠鼻黏膜组织切片HE染色显示,LFK组、TN组的嗜酸粒细胞计数与阳性对照组相比均明显减少(t值分别为3.44和2.97,P值分别为0.014和0.025),但两组的嗜酸粒细胞计数仍明显高于阴性对照组(t值分别为2.54和3.39,P值分别为0.044和0.015).③在42 d,LFK组小鼠的血清IL-4和OVA特异性IgE水平、脾细胞培养液中IFN-γ和IL-4水平与阳性对照组相比,差异均无统计学意义(P值均＞0.05).TN组小鼠血清IFN-γ水平为(27.07 ±3.83) pg/ml,明显高于LFK组的(14.83 ±0.99) pg/ml,差异有统计学意义(Z=2.49,P=0.016),但与阴性对照组的(37.12±1.65) pg/ml相比差异无统计学意义(Z=1.18,P=0.343).TN组小鼠血清IL-4水平为(34.48±7.53) pg/ml,明显低于阳性对照组的(58.68±6.59) pg/ml,差异有统计学意义(Z=2.11,P=0.035),但明显高于阴性对照组的(20.22±1.75) pg/ml,差异有统计学意义(Z=2.31,P=0.021).TN组小鼠脾细胞培养液中IFN-γ水平明显高于LFK组(Z=2.72,P=0.03)和阳性对照组(Z =2.30,P=0.029),而IL-4水平(Z=2.12,P=0.034)以及血清OVA特异性IgE水平(Z=2.31,P=0.021)明显低于阳性对照组,差异均有统计学意义.结论 在AR小鼠模型,经口给予益生菌制品LFK或TN均可减轻鼻部变应性症状,减少鼻黏膜组织的嗜酸粒细胞浸润.TN具有显著的调节细胞因子IFN-γ和IL-4水平的作用,且对抗原特异性IgE水平具有明显的抑制作用.

abstractsObjective The aim of this study was to investigate the anti-allergic effects of lysozyme/ heat-treated Enterococcus faecalis FK-23 (LFK) and heat-treated Enterococcus faecium sp.TN-3 (TN) on experimental allergic rhinitis (AR).Methods A total of twenty-four BALB/c mice were divided into four groups randomly:(1) positive control group,(2) LFK-fed group,(3) TN-fed group,and (4) negative control group.To establish the murine AR model,intraperitoneal injection and nasal drip with ovalbumin (OVA) were performed.Saline was used instead of OVA for negative control.Probiotic preparations of LFK and TN were orally administrated for 42 days [60 mg (0.5 ml)/d] in LFK-fed and TN-fed mice,respectively.The positive and negative control mice received saline orally for 42 days.Nasal rubbing and sneezing were monitored on d 21,d 27,and d 35.After the final challenge,mice were sacrificed on d 42,and eosinophilic infiltration into the nasal mucosa was quantified (H&E stain).IFN-γ,IL-4 and OVAspecific IgE levels in the sera and splenocyte culture supernatants were determined by ELISA kits.Results Nasal rubbing of LFK-fed mice was significantly reduced compared to the positive control group on day 27 (t =2.95,P =0.028).Both in the LFK-fed and TN-fed mice,nasal rubbing (t value was 3.75 and 3.06,P value was 0.005 and 0.011,respectively) and sneezing (t value was 2.56 and 3.35,P value was 0.038and 0.01,respectively) were significantly decreased compared to the positive control group on d 35.The H&E strain section of nasal tissue showed that eosinophil influx into the nasal mucosa decreased significantly both in the LFK-fed and TN-fed mice compared to the positive control group on day 42 (t value was 3.44 and 2.97,P value was 0.014 and 0.025,respectively) ; however,the LFK-fed mice and TN-fed mice had significant eosinophil influx into the nasal mucosa than that in the negative control group (t value was 2.54 and 3.39,P value was 0.044 and 0.015,respectively).There were no significant differences in the serum levels of IL-4 and OVA-specific IgE,as well as the levels of IFN-γ and IL-4 in splenocyte culture supernatants between the LFK-fed group and positive control group on d 42 (all P ＞ 0.05).Interestingly,the TN-fed mice had significantly higher serum levels of IFN-γ compared to the LFK-fed mice [TN-fed mice:(27.07 ±3.83) pg/ml,LFK-fed mice:(14.83 ±0.99) pg/ml; Z =2.49,P =0.016],but not the negative control group [negative control group:(37.12 ± 1.65) pg/ml ;Z =1.18,P =0.343] on day 42.The serum levels of IL-4 were significantly lower in the TN-fed mice than those in the positive control group [TN-fed mice:(34.48 ± 7.53) pg/ml,positive control group:(58.68 ± 6.59) pg/ml ; Z =2.11,P =0.035] ; however,the levels were significantly higher in the TN-fed mice than those in the negative control group [negative control group:(20.22 ± 1.75) pg/ml; Z =2.31,P =0.021].The TN-fed mice had significantly higher levels of IFN-γin splenocyte culture supernatants compared to the LFK-fed mice (Z =2.72,P =0.03) and the positive control group (Z =2.30,P =0.029),whilst the splenocyte culture supernatant levels of IL-4 (Z =2.12,P =0.034) and the serum levels of OVA-specific IgE (Z =2.31,P =0.021) were significantly lower in the TN-fed mice compared to the positive control mice.Conclusions It is suggested that oral administration of probiotic LFK or TN may alleviate nasal symptoms and reduce nasal eosinophilia in the murine AR model.TN supplementation has obviously regulatory effects on the cytokine levels of IFN-γand IL-4,and significantly inhibitory effects on antigen-specific IgE levels.