PDF(Pubmed)
Abstract：
BACKGROUND: Tropomyosins (TM) from vertebrates are generally non-allergenic, while invertebrate homologs are potent pan-allergens. This study aims to compare the risk of sensitization between chicken TM and shrimp TM through affecting the intestinal epithelial barrier integrity and type 2 mucosal immune activation.
METHODS: Epithelial activation and/or barrier effects upon exposure to 2-50 μg/mL chicken TM, shrimp TM or ovalbumin (OVA) as a control allergen, were studied using Caco-2, HT-29MTX, or HT-29 intestinal epithelial cells. Monocyte-derived dendritic cells (moDC), cocultured with HT-29 cells or moDC alone, were exposed to 50 μg/mL chicken TM or shrimp TM. Primed moDC were cocultured with naïve Th cells. Intestinal barrier integrity (TEER), gene expression, cytokine secretion and immune cell phenotypes were determined in these human in vitro models.
RESULTS: Shrimp TM, but not chicken TM or OVA exposure, profoundly disrupted intestinal barrier integrity and increased alarmin genes expression in Caco-2 cells. Proinflammatory cytokine secretion in HT-29 cells was only enhanced upon shrimp TM or OVA, but not chicken TM, exposure. Shrimp TM enhanced the maturation of moDC and chemokine secretion in the presence or absence of HT-29 cells, while only in the absence of epithelial cells chicken TM activated moDC. Direct exposure of moDC to shrimp TM increased IL13 and TNFα secretion by Th cells cocultured with these primed moDC, while shrimp TM exposure via HT-29 cells cocultured with moDC sequentially increased IL13 expression and IL4 secretion in Th cells.
CONCLUSIONS: Shrimp TM, but not chicken TM, disrupted the epithelial barrier while triggering type 2 mucosal immune activation, both of which are key events in allergic sensitization.
METHODS: Epithelial activation and/or barrier effects upon exposure to 2-50 μg/mL chicken TM, shrimp TM or ovalbumin (OVA) as a control allergen, were studied using Caco-2, HT-29MTX, or HT-29 intestinal epithelial cells. Monocyte-derived dendritic cells (moDC), cocultured with HT-29 cells or moDC alone, were exposed to 50 μg/mL chicken TM or shrimp TM. Primed moDC were cocultured with naïve Th cells. Intestinal barrier integrity (TEER), gene expression, cytokine secretion and immune cell phenotypes were determined in these human in vitro models.
RESULTS: Shrimp TM, but not chicken TM or OVA exposure, profoundly disrupted intestinal barrier integrity and increased alarmin genes expression in Caco-2 cells. Proinflammatory cytokine secretion in HT-29 cells was only enhanced upon shrimp TM or OVA, but not chicken TM, exposure. Shrimp TM enhanced the maturation of moDC and chemokine secretion in the presence or absence of HT-29 cells, while only in the absence of epithelial cells chicken TM activated moDC. Direct exposure of moDC to shrimp TM increased IL13 and TNFα secretion by Th cells cocultured with these primed moDC, while shrimp TM exposure via HT-29 cells cocultured with moDC sequentially increased IL13 expression and IL4 secretion in Th cells.
CONCLUSIONS: Shrimp TM, but not chicken TM, disrupted the epithelial barrier while triggering type 2 mucosal immune activation, both of which are key events in allergic sensitization.
摘要：
背景：来自脊椎动物的原肌球蛋白（TM）通常是非过敏性的，而无脊椎动物同源物是有效的泛过敏原。本研究旨在比较鸡TM和虾TM通过影响肠上皮屏障完整性和2型粘膜免疫激活致敏的风险。
方法：暴露于2-50μg/mL鸡TM后的上皮激活和/或屏障效应，虾TM或卵清蛋白（OVA）作为对照过敏原，使用Caco-2，HT-29MTX，或HT-29肠上皮细胞。单核细胞来源的树突状细胞（moDC），与HT-29细胞或单独的moDC共培养，暴露于50μg/mL鸡TM或虾TM。将引发的moDC与初始Th细胞共培养。肠屏障完整性（TEER），基因表达，在这些人体外模型中确定细胞因子分泌和免疫细胞表型。
结果：虾TM，但不是鸡TM或OVA暴露，在Caco-2细胞中严重破坏了肠屏障的完整性并增加了alarmin基因的表达。HT-29细胞中的促炎细胞因子分泌仅在虾TM或OVA时增强，但不是鸡肉TM，暴露。在有或没有HT-29细胞的情况下，虾TM增强了moDC和趋化因子分泌的成熟，而只在缺乏上皮细胞的鸡TM激活moDC。将moDC直接暴露于虾TM会增加与这些引发的moDC共培养的Th细胞的IL13和TNFα分泌，而通过HT-29细胞与moDC共培养的虾TM暴露会依次增加Th细胞中IL13的表达和IL4的分泌。
结论：虾TM，但不是鸡肉TM，破坏上皮屏障，同时触发2型粘膜免疫激活，两者都是过敏致敏的关键事件。
方法：暴露于2-50μg/mL鸡TM后的上皮激活和/或屏障效应，虾TM或卵清蛋白（OVA）作为对照过敏原，使用Caco-2，HT-29MTX，或HT-29肠上皮细胞。单核细胞来源的树突状细胞（moDC），与HT-29细胞或单独的moDC共培养，暴露于50μg/mL鸡TM或虾TM。将引发的moDC与初始Th细胞共培养。肠屏障完整性（TEER），基因表达，在这些人体外模型中确定细胞因子分泌和免疫细胞表型。
结果：虾TM，但不是鸡TM或OVA暴露，在Caco-2细胞中严重破坏了肠屏障的完整性并增加了alarmin基因的表达。HT-29细胞中的促炎细胞因子分泌仅在虾TM或OVA时增强，但不是鸡肉TM，暴露。在有或没有HT-29细胞的情况下，虾TM增强了moDC和趋化因子分泌的成熟，而只在缺乏上皮细胞的鸡TM激活moDC。将moDC直接暴露于虾TM会增加与这些引发的moDC共培养的Th细胞的IL13和TNFα分泌，而通过HT-29细胞与moDC共培养的虾TM暴露会依次增加Th细胞中IL13的表达和IL4的分泌。
结论：虾TM，但不是鸡肉TM，破坏上皮屏障，同时触发2型粘膜免疫激活，两者都是过敏致敏的关键事件。
