Prenatal control of offspring airway responsiveness

我们最近发现野生型小鼠之间的气道生理学存在根本性差异 由野生型母亲所生的小鼠和由IL5过表达母亲或屋尘螨（HDM）所生的野生型小鼠 敏感的母亲这些母亲的成年野生型后代的气道反应更灵敏， 需要胎儿嗜酸性粒细胞增多的效应，其是母体IL 5穿过胎盘的结果。 随后的致敏和挑战与屋尘螨产生更严重的支气管收缩。 该项目的中心假设是，妊娠期间高循环IL 5诱导胎儿 嗜酸性粒细胞增多，这会导致气道神经支配的永久性变化， 支气管收缩在这个项目中，我们建议确定气道高反应性的机制， 这些WT后代是IL 5转基因母体的后代。我们将描述气道神经结构的变化， 递质和受体表达。我们提出三个具体目标： 具体目的#1：测试母体IL 5tg和母体HDM激发对反射的影响 支气管收缩、副交感神经功能和平滑肌功能。康贝特人将以 在母体HDM激发模型中，母体胎儿转移IL 5的作用，并测试母体和胎儿转移IL 5的作用。 胎儿嗜酸性粒细胞增多症在这些影响。我们还将剖析严重的、致命的支气管收缩的机制 并且当这些成年后代受到抗原攻击时增强气道炎症。 特定目的#2：测试子宫内暴露于IL 5是否会改变结构或神经递质含量 感觉神经和副交感神经我们将使用我们的新成像方法来确定上皮和 平滑肌神经支配，并量化感觉和 副交感神经 具体目标#3：确定气道上皮神经营养因子在以下方面的作用：1）对 抗原激发，2）严重气道高反应性，和3）维持气道神经重塑， IL5tg母亲的成年后代和HDM致敏和激发母亲的成年后代。我们将 将我们对神经营养因子表达的初步研究扩展到包括不同的小鼠模型， 目标#1中的治疗，并确定通过用抗体阻断而升高的神经营养因子的作用 以及用受体拮抗剂治疗动物。

We have recently shown that there is a fundamental difference in airway physiology between wildtype mice born to wildtype mothers and wildtype mice born to IL5 overexpressing mothers or housedust mite (HDM) sensitized mothers. The airways of adult wildtype offspring of these mothers are much more responsive, an effect that requires fetal eosinophilia that develops as the result of maternal IL5 crossing the placenta. Subsequent sensitization and challenge with housedust mite yields much more severe bronchoconstriction. The central hypothesis of this project is that high circulating IL5 during pregnancy induces fetal eosinophilia, and that this causes permanent changes in airway innervation that increase bronchoconstriction. In this project, we propose to determine the mechanisms of airway hyperreactivity in these WT offspring of IL5 transgenic mothers. We will characterize changes in airway nerve structure, transmitters, and receptor expression. We propose three specific aims: SPECIFIC AIM #1: Test the effects of maternal IL5tg and maternal HDM challenge on reflex bronchoconstriction, parasympathetic nerve function, and smooth muscle function. We will determine the role of maternal fetal transfer of IL5 in the maternal HDM challenge model, and test the role of maternal and fetal eosinophilia in these effects. We will also dissect the mechanisms of severe, lethal bronchoconstriction and potentiated airway inflammation when these adult offspring are antigen challenged. SPECIFIC AIM #2: Test whether exposure to IL5 in utero alters the architecture or neurotransmitter content of sensory and parasympathetic nerves. We will use our novel imaging method to determine epithelial and smooth muscle innervation, and to quantify changes in neurotransmitter expression in sensory and parasympathetic nerves. SPECIFIC AIM #3: To determine the role of airway epithelial neurotrophins in 1) heightened response to antigen challenge, 2) severe airway hyperresponsiveness, and 3) maintenance of airway nerve remodeling in adult offspring of IL5tg mothers and in adult offspring of HDM sensitized and challenged mothers. We will extend our preliminary studies of neurotrophin expression to include the different mouse models and treatments in Aim #1, and determine the roles of neurotrophins that are elevated by blocking with antibodies and treating animals with receptor antagonists.