对虾原肌球蛋白致敏小鼠模型的构建及乳酸菌肠黏膜免疫效应对致敏性的影响

以原肌球蛋白（tropomyosin，TM）为主要过敏原，腹腔注射6 周龄BALB/c雌、雄小鼠，从第14天开始给治疗组小鼠口服灌胃长双歧杆菌婴儿亚种（Bifidobacterium longum subsp.）1.2202或芽孢乳酸菌09.712（Bacillus coagulans 09.712），连续灌胃20 d。根据小鼠腹泻情况、过敏症状评分、血清中组胺（histamine，HIS）质量浓度、TM特异性免疫球蛋白（immunoglobulin，Ig）E水平变化构建TM致敏及益生菌治疗小鼠模型；通过氯乙酸萘酚酯酶染色、高碘酸希夫试剂特殊染色法检测各组小鼠肠道部位的肥大细胞和杯状细胞，通过免疫组化法检测各组小鼠肠道部位的CD4＋ T细胞和嗜酸性粒细胞；探究肠黏膜免疫在TM致敏及益生菌缓解TM致敏作用中的机理。结果表明：雌性小鼠更适用于构建TM致敏模型；益生菌灌胃可以通过降低血清中HIS质量浓度和IgE水平缓解肠黏膜免疫反应，减轻TM过敏症状。本研究从肠黏膜免疫反应角度探究了其在TM致敏中的作用，为食物过敏的研究提供参考。

Construction of Tropomyosin-Sensitized Mouse Model and Effect of Lactic Acid Bacteria-Induced Intestinal Mucosal Immunity on Allergenicity

This study was devised to elucidate the role of intestinal mucosal immunity in the sensitization of mice by tropomyosin (TM) and in the alleviation of allergy symptoms by probiotics. Female and male BALB/c mice were sensitized and challenged by intraperitoneal (IP) injection of TM and were treated by oral administration of Bifidobacterium longum subsp. 1.2202 or Bacillus coagulans 09.712 for 20 consecutive days starting from Day 14. Anaphylaxis and diarrhea were evaluated, serum immunoglobulin(Ig)E and histamine (HIS) levels were determined. Intestinal mucosal mast cells and goblet cells were detected by histological analysis. Eosinophils and CD4＋ T cells were identified by immunohistochemistry. The results showed that female mice were more suitable for building TM-induced mouse model and probiotics could alleviate the allergy symptoms by downregulating intestinal mucosal immune response as manifested by decreased levels of HIS and TM-specific IgE. These results provide a theoretical basis for the mechanistic study of TM-induced food allergy and for understanding the therapeutic effect of probiotics on food allergy.