Biomarker discovery for immunodiagnosis of invasive candidiasis

描述（由申请人提供）：侵袭性念珠菌病（IC）是危重环境中对患者最严重的威胁之一。在美国，每年有多达6万个案例，与IC相关的总成本可能高达每年20 - 40亿美元。早期诊断是影响患者预后的最关键因素之一。该项目的目标是一种快速和廉价的免疫测定方法，将使用血清作为样本来识别IC的存在。这是对念珠菌病诊断的未满足需求，特别是对患者护理点附近的测试。目标人群将是那些先进的医疗干预和使用强效细胞毒性药物导致念珠菌深层感染扩散的个体。总体假设是念珠菌的蛋白抗原以可作为疾病生物标志物的浓度进入血液。该方法将对两种或两种以上不同抗原的存在进行免疫测定，1)在引起IC的念珠菌属中共享，2)在感染期间流入血液。同时检测多种抗原可显著提高预测价值。该产品将通过侧流免疫测定（LFI）和/或酶联免疫测定（ELISA）平台进行检测。到目前为止，我们已经使用了一种新的生物标志物发现过程，称为体内微生物抗原发现（InMAD），以鉴定5种候选蛋白质。Specific Aim 1将重复该实验，并确定至少5个额外的候选生物标志物（总共10个蛋白质）。目标2将使用来自动物模型和人类的IC血清样本确认至少5种蛋白质是真正的生物标志物。如果I期成功，II期申请将I)生成针对生物标记蛋白的单克隆抗体，II)构建LFI或ELISA格式的原型免疫分析，iii)进行IC诊断的临床前研究。

DESCRIPTION (provided by applicant): Invasive candidiasis (IC) is one of the most serious threats to patients in a critical setting. With as many as 60,000 cases per year in the U.S., the total cost associated with IC in the U.S. may be as high as $2-4 billion/year. One of the most critical factors influencing patient outcome is early diagnosis. The goal of this project is a rapi and inexpensive immunoassay that will use serum as a sample to identify the presence of IC. This is an unmet need for diagnosis of candidiasis, particularly for tests near the point of patien care. The target population will be individuals for whom advanced medical intervention and use of potent cytotoxic drugs have led to a proliferation of deep-seated infection by Candida spp. The overall hypothesis is that protein antigens of Candida spp. are shed into blood in concentrations that would be biomarkers for disease. The approach will be immunoassay for the presence of two or more distinct antigens that i) are shared across Candida spp. that cause IC and ii) are shed into blood during infection. Simultaneous detection of multiple antigens will markedly enhance the predictive value. The product will be assays with the lateral flow immunoassay (LFI) and/or enzyme-linked immunoassay (ELISA) platforms. To date, we have used a novel biomarker discover process termed In vivo Microbial Antigen Discovery (InMAD) to identify 5 candidate proteins. Specific Aim 1 will repeat this experiment and identify at least 5 additional candidate biomarkers (total of 10 proteins). Aim 2 will confirm at least 5 proteins as genuine biomarkers using IC serum samples from animal models and humans. If Phase I is successful, a Phase II application would i) generate monoclonal antibodies to biomarker proteins, ii) construct prototype immunoassays in LFI or ELISA format and iii) perform pre-clinical studies for diagnosis of IC.