Benedé Sara, Pérez-Rodríguez Leticia, Martínez-Blanco Mónica, Molina Elena, López-Fandiño Rosina
Instituto de Investigación en Ciencias de la Alimentación (CIAL, CSIC-UAM), 28049 Madrid, Spain.
Foods. 2021 Mar 9;10(3):561. doi: 10.3390/foods10030561.
House dust mite (HDM) induces Th2 responses in lungs and skin, but its effects in the intestine are poorly known. We aimed to study the involvement of HDM in the initial events that would promote sensitization through the oral route and eventually lead to allergy development.
BALB/c mice were exposed intragastrically to proteolytically active and inactive HDM, as such, or in combination with egg white (EW), and inflammatory and type 2 responses were evaluated. Oral administration of HDM, by virtue of its proteolytic activity, promoted the expression, in the small intestine, of genes encoding tight junction proteins, proinflammatory and Th2-biasing cytokines, and it caused expansion of group 2 innate immune cells, upregulation of Th2 cytokines, and dendritic cell migration and activation. In lymphoid tissues, its proteolytically inactivated counterpart also exerted an influence on the expression of surface DC molecules involved in interactions with T cells and in Th2 cell differentiation, which was confirmed in in vitro experiments. However, in our experimental setting we did not find evidence for the promotion of sensitization to coadministered EW.
Orally administered HDM upregulates tissue damage factors and also acts as an activator of innate immune cells behaving similarly to potent oral Th2 adjuvants.
屋尘螨（HDM）可在肺部和皮肤诱导Th2反应，但其在肠道中的作用尚不清楚。我们旨在研究HDM在通过口服途径促进致敏并最终导致过敏发生的初始事件中的作用。
将BALB/c小鼠经胃内给予具有蛋白水解活性和无活性的HDM，单独给予或与蛋清（EW）联合给予，并评估炎症反应和2型反应。由于其蛋白水解活性，口服HDM可促进小肠中编码紧密连接蛋白、促炎和偏向Th2的细胞因子的基因表达，并导致2型固有免疫细胞扩增、Th2细胞因子上调以及树突状细胞迁移和活化。在淋巴组织中，其蛋白水解失活的对应物也对参与与T细胞相互作用和Th2细胞分化的表面树突状细胞分子的表达产生影响，这在体外实验中得到证实。然而，在我们的实验环境中，未发现促进对共同给予的EW致敏的证据。
口服HDM可上调组织损伤因子，并且还作为一种固有免疫细胞激活剂，其作用类似于强效口服Th2佐剂。
