TSG6 in IgE mediated Food Allergy

描述(申请人提供)：食物过敏和食物过敏是虚弱和危及生命的情况。为了更好地了解食物过敏反应的分子机制，我们实验室广泛研究了口服过敏原诱导的IgE依赖型肠道过敏反应的小鼠模型(1)。有趣的是，我们最近发现这一模型的特征是分泌蛋白TSG6mRNA、肿瘤坏死因子诱导基因6的表达增加。同时，我们还发现TSG6mRNA在人类食物过敏相关疾病嗜酸性食管炎(EE)中表达上调(2)。综上所述，这些观察将我们的注意力集中在揭示TSG6在食物过敏相关反应中的作用上。TSG6是一种有效的中性粒细胞募集抑制剂；一些研究通过增加与透明质酸的结合倾向间接地将TSG6与淋巴细胞黏附和激活联系在一起(6-8)；TSG6增加了蛋白酶的活性。我们目前的研究将集中于了解TSG6在小鼠和人类食物过敏相关反应中的表达和作用。目的：研究TSG6在小鼠和人食物过敏相关反应中的表达。为此，我们假设在实验性肠过敏、实验性EE和人类EE的诱导过程中，TSG6的mRNA和蛋白水平将上调。我们将定义在这两个系统中表达TSG6的动力学和细胞类型。实时荧光定量聚合酶链式反应和酶联免疫吸附试验将被用来定量小鼠的基因和蛋白表达。将通过免疫组织化学、原位杂交和流式细胞仪分析来确定TSG6在胃肠道中的表达模式。目的II：明确TSG6在实验性肠道过敏反应中的作用。为了达到这个目的，我们假设TSG6基因缺陷的小鼠会患上与Th2相关的疾病，即延缓腹泻的发生。因此，我们将使用ELISA、流式细胞术和组织染色技术评估各种临床、病理和免疫学终点。目的III：明确TSG6在实验性EE中的作用。为此，我们假设TSG6将促进EE的发展，特别是在嗜酸性粒细胞募集和组织重塑方面，同时抑制中性粒细胞炎症。TSG6基因缺陷的小鼠将受到实验性EE的影响，适应性和先天免疫反应的发展将被评估，以及使用ELISA法、免疫组织化学和蛋白酶活性分析来评估组织重塑。潜在影响：我们希望这项研究将揭开与IgE介导的炎症有关的新的分子机制，并将有助于更好地了解这种疾病。我们相信，这项研究将是开发以TSG6为靶点治疗IgE介导的食物过敏相关疾病的新治疗方法的里程碑。食物过敏和食物过敏是使人虚弱和危及生命的疾病。这些拨款申请的总体目标是揭示TSG6在食物过敏相关反应中的作用。

DESCRIPTION (provided by applicant): Food allergy and food anaphylaxis are debilitating and life threatening conditions. In order to better understand the molecular mechanisms underlying food anaphylaxis, our laboratory has extensively studied a murine model of oral allergen-induced IgE-dependent intestinal anaphylaxis (1). Interestingly, we recently uncovered that this model was characterized by an increased expression of the secreted protein TSG6 mRNA, tumor necrosis factor induced gene 6. At the same time, we also discovered that TSG6 mRNA was upregulated in a human food allergy related disease, eosinophilic esophagitis (EE) (2). Taken together, these sets of observations have focused our attention on uncovering the role of TSG6 in food allergy related responses. TSG6 is a potent inhibitor of neutrophil recruitment; some studies have indirectly associated TSG6 to lymphoid cell adhesion and activation through its propensity to increase binding to hyaluroan (6-8); and TSG6 increases protease activity. Our present study will focus on understanding the expression and role of TSG6 in food allergy-related responses in mice and humans. Aim I: To characterize TSG6 expression in murine and human food allergy related responses. In this aim, we hypothesize that TSG6 mRNA and protein levels will be upregulated during induction of experimental intestinal anaphylaxis, experimental EE, and human EE. We will define the kinetics and cell types that express TSG6 in both systems. Real-time PCR and ELISA will be used to quantify the mRNA and protein expression in mice. Immunohistochemistry, in situ hybridization, and flow cytometry analysis will be carried out to identify the TSG6 expression pattern in the gastrointestinal tract. Aim II: To define the role of TSG6 in vivo in experimental intestinal anaphylaxis. In this aim, we hypothesize that TSG6-deficient mice will develop attenuated Th2-associated diseases, i.e., a delay in diarrhea occurrence. Accordingly, we will assess a variety of clinical, pathological, and immunological endpoints using ELISA, flow cytometry, and tissue staining techniques. Aim III: To define the role of TSG6 in experimental EE. In this aim, we hypothesize that TSG6 will promote the development of EE, especially in eosinophil recruitment and tissue remodeling while inhibiting neutrophilic inflammation. TSG6-deficient mice will be subjected to experimental EE and the development of adaptive and innate immune responses will be assessed, as well as tissue remodeling using ELISA, immunohistochemistry, and protease activity assays. Potential impact: We are hopeful that this study will unravel new molecular mechanisms involved in IgE- mediated inflammation and will help provide a better understanding of the disease. We believe that this study will be a milestone in the development of new therapeutic approaches aiming to target TSG6 for IgE-mediated food allergy related diseases. Food allergy and food anaphylaxis are debilitating and life threatening conditions. The overall goal of these grant application is to uncover the role of TSG6 in food allergy related responses.