A New Cytokine-Based Immunoassay for the Diagnosis of Lyme Disease

描述（由申请人提供）：莱姆病（LD）由硬蜱传播的螺旋体伯氏疏螺旋体（Bb）引起，是美国最常见的病媒传播疾病。尽管采取了公共卫生预防措施，但每年的确诊病例发病率已上升至近3万例，其中绝大多数发生在东北部。播散性感染会导致皮肤、心脏、关节和神经系统疾病，并且可能更难治疗。虽然在感染早期使用抗生素可达到临床治愈，但延迟使用抗生素可能会导致严重的并发症。 诊断和治疗可能导致大量的发病率和可能持续存在的不明症状的医疗保健支出。因此，及时准确地诊断LD对于优化治疗和预防疾病的长期后遗症至关重要。目前，检测Bb反应性抗体的血清学试验是LD诊断的主要方法，但在感染早期敏感性低，不能区分先前暴露于Bb与活动性感染，并且不能用于评估对治疗的反应。该提案旨在通过开发基于在皮肤中表达的和/或在哺乳动物宿主中Bb感染和持久性所需的新的Bb抗原组的LD的新的诊断细胞因子测定来改进当前的血清学测试。该提案的R21阶段将首先使用多重细胞因子测定来确定重组Bb蛋白/合成肽是否引起从新诊断的活动性LD患者获得的全血中产生细胞因子。然后，我们将优化测定条件，包括细胞因子选择和Bb蛋白组合，以产生将在R33阶段进一步验证的精制全血细胞因子测定。在R33阶段进行的大量LD受试者和对照的前瞻性研究中，我们将定义全血细胞因子测定的灵敏度和特异性，并确定测定中的阳性反应是否与抗生素治疗后的持续症状相关。作为补充当前血清学试验的策略，全血细胞因子测定将提高LD诊断的组合灵敏度和特异性，特别是在单独的血清学试验表现不佳的情况下。 公共卫生相关性：莱姆病，由于感染蜱传螺旋体伯氏疏螺旋体，是最常见的病媒传播的疾病在美国。及时诊断感染对于治疗的最佳反应和预防长期后遗症非常重要。本项目将评估全血细胞因子检测的实用性， 播散型B。用于监测治疗效果。

DESCRIPTION (provided by applicant): Lyme disease (LD), caused by the Ixodes tick-borne spirochete Borrelia burgdorferi (Bb), is the most common vector-borne disease in the United States. Despite public health preventive measures, the annual confirmed case incidence has risen to nearly 30,000, the vast majority of which occur in the Northeast. Disseminated infection causes disease in the skin, heart, joints and nervous system and can be more difficult to treat. Although antibiotics achieve clinical cure when administered in early stages of infection, delay in diagnosis and treatment can lead to substantial morbidity and health care expenditures for unexplained symptoms that may persist. Timely and accurate diagnosis of LD, therefore, is essential for optimizing treatment and preventing long-term sequelae of the disease. Currently, serologic tests that detect Bb-reactive antibodies are the mainstay of LD diagnostics, but have low sensitivity early in infection, do not distinguish previous exposure to Bb from active infectio, and cannot be used to assess response to therapy. This proposal seeks to improve upon current serologic tests by developing a new diagnostic cytokine assay for LD based on a novel panel of Bb antigens expressed in the skin and/ or required for Bb infection and persistence in the mammalian host. The R21 phase of the proposal will first use a multiplex cytokine assay to determine whether recombinant Bb proteins/synthetic peptides elicit cytokine production from whole blood obtained from patients with newly diagnosed, active LD. We will then optimize the assay conditions, including cytokine selection and Bb protein combination, to produce a refined whole blood cytokine assay that will be further validated in the R33 phase. In a prospective study of a large number of LD subjects and controls conducted during the R33 phase, we will define the sensitivity and specificity of the whole blood cytokine assay and determine whether positive responses in the assay are associated with persistent symptoms after antibiotic treatment. As a strategy that complements current serologic tests, the whole blood cytokine assay will improve the combined sensitivity and specificity of LD diagnostics, especially in situations in which the serologic tests alone under-perform. PUBLIC HEALTH RELEVANCE: Lyme disease, due to infection with the tick-borne spirochete Borrelia burgdorferi, is the most common vector-borne disease in the United States. Timely diagnosis of infection is important for optimal response to therapy and to prevent long-term sequelae. This project will assess the utility of a whole blood cytokine assay for the detection of disseminated B. burgdorferi infection and for monitoring efficacy of treatment.