Li Fei, Li Hai-qi
Department of Primary Child Care, Children's Hospital, Chongqing University of Medical Sciences, Chongqing 400014, China.
Zhonghua Er Ke Za Zhi. 2006 Apr;44(4):294-8.
To valuate the intestinal mucosal secretary IgA (sIgA) responses to the ovalbumin-induced allergy in mice, to provide some clues for the exploration of mechanisms and therapeutic methods in the children's food allergy.
Female BALB/c mice aged 6 weeks fed on the ovalbulmin-free diet, were randomly divided into 2 groups with 8 mice in each. The mice in group Ch were sensitized with ovalbumin (OVA) intraperitoneal injection two times and challenged intragastrically 3 times. Two days after the last challenge with oral OVA, the mice were sacrificed and the samples were collected. The mice in group Ns were given intraperitoneal and intragastrical normal saline as control. The levels of total IgA and OVA-specific IgA in the intestinal mucus of the mice were determined by ELISA; the immunohistochemical methods were adopted to observe IgA(+) plasmacytes in lamina propria (LP) and surface membrane IgA (smIgA)(+) lymphocytes in peyer's patch (PP); the IL-4 mRNA expression in LP was assessed by RT-PCR. The IL-4 mRNA expression in PP was evaluated by in situ hybridization.
After the mice in Ch group were sensitized and challenged with OVA, the levels of the total IgA and the OVA-specific IgA in mucus remarkably increased (P < 0.01 respectively), the amounts of the IgA(+) plasmacytes in LP and the smIgA(+) lymphocytes in PP significantly increased (P < 0.01 respectively); a significantly positive correlation was found among the total IgA levels, the OVA-specific IgA levels, the IgA(+) plasmacyte counts in LP and the smIgA(+) lymphocyte counts in PP (P < 0.01 respectively); the mRNA expressions of IL-4 in LP and in PP were significantly augmented (P < 0.01 respectively); significantly positive correlations were found either between the IL-4 mRNA expression and the IgA(+) plasmacyte counts in LP (P < 0.01) or between the IL-4 mRNA expression and the smIgA(+) lymphocyte counts in PP (P < 0.01).
The intestinal mucosal sIgA responses are abnormally augmented in the ovalbumine-induced allergic mice, which may be partly due to the increased expression of IL-4 mRNA in gut.
评估小鼠肠道黏膜分泌型免疫球蛋白A（sIgA）对卵清蛋白诱导的过敏反应，为儿童食物过敏的机制探索及治疗方法提供线索。
6周龄无卵清蛋白饮食的雌性BALB/c小鼠，随机分为2组，每组8只。Ch组小鼠腹腔注射卵清蛋白（OVA）致敏2次，灌胃激发3次。末次口服OVA激发后2天处死小鼠并采集样本。Ns组小鼠腹腔及灌胃给予生理盐水作为对照。采用ELISA法检测小鼠肠道黏液中总IgA和OVA特异性IgA水平；采用免疫组化方法观察固有层（LP）中IgA（+）浆细胞及派伊尔结（PP）中表面膜IgA（smIgA）（+）淋巴细胞；采用RT-PCR法检测LP中IL-4 mRNA表达。采用原位杂交法评估PP中IL-4 mRNA表达。
Ch组小鼠经OVA致敏和激发后，黏液中总IgA和OVA特异性IgA水平显著升高（分别为P < 0.01），LP中IgA（+）浆细胞数量及PP中smIgA（+）淋巴细胞数量显著增加（分别为P < 0.01）；总IgA水平、OVA特异性IgA水平、LP中IgA（+）浆细胞计数及PP中smIgA（+）淋巴细胞计数之间存在显著正相关（分别为P < 0.01）；LP和PP中IL-4 mRNA表达显著增强（分别为P < 0.01）；IL-4 mRNA表达与LP中IgA（+）浆细胞计数之间（P < 0.01）以及IL-4 mRNA表达与PP中smIgA（+）淋巴细胞计数之间（P < 0.01）均存在显著正相关。
卵清蛋白诱导的过敏性小鼠肠道黏膜sIgA反应异常增强，这可能部分归因于肠道中IL-4 mRNA表达增加。
