OSPA-NEGATIVE ELISA FOR LYME DISEASE

一个重要的公共卫生需求是标准化的血清诊断莱姆病检测，以区分由于接种外表面蛋白A(OspA)疫苗而导致的感染和假阳性。使用缺乏OspA抗原的伯氏疏螺旋体抗原制剂将开发一种新的酶联免疫吸附试验(ELISA)，OspA抗原是最近获得FDA批准的莱姆病疫苗的主要成分。疫苗接受者产生OspA抗体，通常会导致血清阳性测试结果，无论是否实际发生感染；传统的莱姆病ELISA使用包括表达的OspA在内的伯氏杆菌全细胞裂解物。在第一阶段启动的三种不同的OspA阴性抗原候选制剂将以ELISA形式进行评估，这些候选制剂使用三种不同的方法--变异菌株选择、质粒基因中断和重组抗原表达。敏感性和特异性将使用代表莱姆病早期和晚期的血清试板、正常人血清和其他感染性或自身免疫性疾病患者的血清来确定。最好的酶联免疫吸附试验将在商业参考实验室环境中进一步开发和广泛评估。我们预计，随着OspA疫苗的广泛应用，新的OspA阴性的ELISA将取代目前基于标准伯氏杆菌全细胞裂解物的ELISA。建议的商业应用：这项研究将导致用于商业参考实验室的人类莱姆病的血清学ELISA法诊断。

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.