Plasma Serum Based Biomarkers in Sublingual Oral Immunotherapy for Milk Allergy

基于血浆血清的生物标志物用于舌下口服免疫疗法治疗牛奶过敏

• 批准号: 8424318
• 负责人: JOHN T. SCHROEDER
• 金额: $ 20.25万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-02-15 至 2015-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8424318
• 关键词: Accounting; Acids; Address; Adolescence; Adult; Adverse reactions; Affect; Aftercare; Allergen Immunotherapy; Allergens; Allergic; Antibodies; Area; Basophils; Biological Assay; Biological Markers; Blood; CD34 gene; Cattle; Child; Clinical; Complex; Data; Dendritic Cells; Development; Diet; Disease; Effectiveness; Elements; Food; Food Contamination; Food Hypersensitivity; Food Processing; Future; Goals; Hand; Histamine; Histamine Release; Hypersensitivity; IgE; IgG4; Immune response; Immunoglobulin G; Immunoglobulins; Immunotherapy; In Vitro; Individual; Institution; Interferons; Interleukin-4; Link; Liquid substance; Mediating; Milk; Milk Hypersensitivity; Milk Proteins; Monitor; Oral; Patient Care; Patients; Pilot Projects; Plasma; Play; Pre-Post Tests; Process; Production; Reaction; Recording of previous events; Relative (related person); Reporting; Research Project Grants; Restaurants; Risk; Role; Safety; Sampling; Serum; Specimen; Testing; Time; Work; adult stem cell; airborne allergen; assay development; base; clinical efficacy; clinically relevant; crosslink; cytokine; desensitization; effective therapy; follow-up; food allergen; human SYK protein; in vitro testing; novel strategies; omalizumab; oral immunotherapy; passive sensitization; receptor; research study; response

DESCRIPTION (provided by applicant): Cow's milk allergy (CMA) is the most common food allergy in young children and is now likely to persist into adolescence and adulthood. Strict milk avoidance remains the only treatment for this allergy but accidental reactions, which are often severe, are extremely common, frequently due to the hidden presence of food allergens in processed foods and cross-contamination of foods. Recent studies from our institution and elsewhere have identified oral and sublingual allergen immunotherapy (OIT and SLIT) as promising approaches for treatment of CMA. Studies demonstrate that most children with IgE-mediated CMA can be desensitized to cow's milk protein, both safely and efficaciously. However, the specific mechanisms by which this treatment appears to work remain unknown, and questions remain to whether this increased tolerance to milk after treatment is permanent, or rather represents a transient desensitization which could place patients at significant risk of future reactions if milk was ever discontinued from their diet. Our long-range goal is to develop in vitro tests that help predict risks to adverse reactions to food as well as the safety/clinical efficacy of OIT/SLIT. The best chance of developing a routine test to make such predictions is best achieved with the versatility that serum/plasma provides. Our novel approach of using culture-derived basophils (CDBA) grown from adult stem cells should facilitate identification of plasma markers. Therefore, the proposal consists of 2 aims: Aim 1 involves analyzing plasma from CMA children undergoing SLIT and OIT for "blocking activity" by comparing pre and post specimens in passively sensitizing CDBA for subsequent challenge with milk allergen. The advantage of using CDBA is that they have never been exposed to immunoglobulins (IgE/IgG), which may otherwise confound the ability to detect blocking IgG4 antibody. Similar experiments will test pre- and post- OIT/SLIT plasma specimens for effects on plasmacytoid dendritic cells (pDCs), predicting that post-OIT/SLIT plasma (with greater IgG4 levels) will augment innate immune responses (TLR9) that are seemingly impaired in allergic individuals. Aim 2 explores the existing hypothesis that circulating allergen-IgE complexes are in plasma of CMA subjects and that these can be detected by inducing phenotypic/functional responses in CDBA and/or normal basophil. Plasma specimens from CMA subjects will be tested in flow-based assays for their ability to induce basophil spontaneous histamine release (SHR), the expression of markers (CD63/CD203c) linked to IgE-dependent activation as well as those (syk kinase) that are down regulated with prolonged Fc5RI cross-linking. These assays could result in new plasma-based tests useful in predicting whether one is at risk for adverse reactions and for predicting the clinical efficacy during successful OIT/SLIT. With food specific immunotherapy being potentially the most exciting area in the history of food allergy research, this project, with clinical and mechanistic endpoints should have immediate impact on the care of patients with food allergy.

描述（由申请人提供）：牛奶过敏（CMA）是幼儿中最常见的食物过敏，现在可能会持续到青春期和成年期。严格避免牛奶仍然是这种过敏的唯一治疗方法，但意外反应非常常见，通常很严重，通常是由于加工食品中隐藏的食物过敏原和食品交叉污染造成的。我们机构和其他地方的最新研究已确定口腔和舌下过敏原免疫疗法（OIT 和 SLIT）是治疗 CMA 的有前途的方法。研究表明，大多数患有 IgE 介导的 CMA 的儿童可以安全有效地对牛奶蛋白进行脱敏。然而，这种治疗起作用的具体机制仍然未知，而且治疗后对牛奶的耐受性增加是否是永久性的，或者更确切地说代表短暂的脱敏，如果牛奶曾经存在，可能会使患者面临未来反应的重大风险。停止饮食。我们的长期目标是开发体外测试，帮助预测食品不良反应的风险以及 OIT/SLIT 的安全性/临床疗效。开发常规测试来进行此类预测的最佳机会是通过血清/血浆提供的多功能性来实现。我们使用从成体干细胞生长的培养物衍生的嗜碱性粒细胞（CDBA）的新方法应该有助于血浆标记物的鉴定。因此，该提案包含 2 个目标： 目标 1 涉及通过比较被动致敏 CDBA 之前和之后的样本来分析接受 SLIT 和 OIT 的 CMA 儿童血浆的“阻断活性”，以用于随后的牛奶过敏原挑战。使用 CDBA 的优点是它们从未接触过免疫球蛋白 (IgE/IgG)，否则可能会混淆检测阻断 IgG4 抗体的能力。类似的实验将测试 OIT/SLIT 前后血浆样本对浆细胞样树突状细胞 (pDC) 的影响，预测 OIT/SLIT 后血浆（具有更高的 IgG4 水平）将增强看似受损的先天免疫反应 (TLR9​​)在过敏体质的人中。目标 2 探讨了现有的假设，即循环过敏原-IgE 复合物存在于 CMA 受试者的血浆中，并且可以通过诱导 CDBA 和/或正常嗜碱性粒细胞的表型/功能反应来检测这些复合物。来自 CMA 受试者的血浆样本将通过基于流式的测定来测试其诱导嗜碱性粒细胞自发组胺释放 (SHR) 的能力、与 IgE 依赖性激活相关的标记物 (CD63/CD203c) 的表达以及那些 (syk 激酶)随着 Fc5RI 交联时间的延长而下调。这些测定可能会产生新的基于血浆的测试，可用于预测一个人是否面临不良反应的风险，并预测成功的 OIT/SLIT 期间的临床疗效。由于食物特异性免疫疗法可能是食物过敏研究史上最令人兴奋的领域，因此该项目及其临床和机制终点应该会对食物过敏患者的护理产生直接影响。