OSPA-NEGATIVE ELISA FOR LYME DISEASE

一种标准化的血清诊断莱姆病测试存在着重大的公共卫生需求，该测试可将感染与由于接种外表面蛋白A （OspA）而导致的假阳性区分开来。将开发一种新的酶联免疫吸附试验（ELISA），使用缺乏OspA抗原的伯氏疏螺旋体抗原制剂，OspA抗原是最近获FDA批准的莱姆病疫苗的主要成分。接种者产生OspA抗体，无论是否发生实际感染，通常都会导致血清检测结果呈阳性；传统的莱姆病elisa使用伯氏疏螺旋体的全细胞裂解物，包括表达的OspA。在I期使用三种不同的方法（变异菌株选择、质粒基因破坏和重组抗原表达）启动的三种不同的ospa阴性抗原候选制剂将以ELISA格式进行评估。敏感性和特异性将通过莱姆病早期和晚期血清、正常人血清和其他感染性或自身免疫性疾病患者血清来确定。性能最好的ELISA将在商业参考实验室环境中进一步开发和广泛评价。我们预计，随着OspA疫苗的广泛应用，新的OspA阴性ELISA将取代目前基于标准伯氏疏螺旋体菌株全细胞裂解物的ELISA。拟议的商业应用：这项研究将导致人类莱姆病的血清学ELISA诊断，用于商业参考实验室。

A significant public health need exists for a standardized serodiagnostic Lyme disease test that distinguishes infection from false positives due to outer surface protein A (OspA) vaccination. A new enzyme-linked immunosorbent assay (ELISA) will be developed using Borrelia burgdorferi antigen preparations that lack OspA antigen, the primary constituent of the Lyme disease vaccine recently approved by the FDA. Vaccine recipients generate OspA antibodies typically causing seropositive test results whether or not actual infection occurred; conventional Lyme disease ELISAs use whole-cell lysates of B. burgdorferi including expressed OspA. Three different OspA-negative antigen candidate preparations initiated in Phase I using three different approaches -- variant strain selection, plasmid gene disruption, and recombinant antigen expression -- will be evaluated in ELISA formats. Sensitivity and specificity will be determined using serum panels representing early and late stages of Lyme disease, normal human sera, and sera from patients with other infectious or autoimmune diseases. The best performing ELISA will be further developed and evaluated extensively in a commercial reference laboratory setting. We anticipate that as the OspA vaccine becomes widely used, the new OspA-negative ELISA will supplant current ELISAs based on whole-cell lysates of standard B. burgdorferi strains. PROPOSED COMMERCIAL APPLICATIONS: This research will lead to a serologic ELISA diagnostic for human Lyme disease for use in commercial reference laboratories.