UCLA

Healthcare decisions rely heavily on in vitro diagnostic (IVD) tests. Biomarkers are often employed to develop disease specific IVDs. Reliable early-stage disease detection combined with noninvasive modes of sample collection is the main objective of molecular diagnostics. Saliva is a biofluid rich in diagnostic indicators for both oral and systemic disorders. The innovative diagnostic platform, electric field-induced release and measurement (EFIRM or AmperialTM), utilizes a unique cyclic electric field to enhance sensitivity and specificity of saliva and plasma biomarker detection. With the global impact of Coronavirus disease 2019 (COVID-19), IVDs that can enable a larger scale of testing would be immensely beneficial. A quantitative EFIRM assay for anti-SARS-CoV-2 Spike IgG in saliva was developed with analytical specificity of 99.9999994% with 100% sensitivity for hospitalized and 88% for asymptomatic patients. Additionally, positive predictive value of 96% was achieved suggesting it to be an effective tool for population screening. Employing this CLIA validated test in the antibody kinetics study, 30% of vaccinated individuals had >90% drop from peak antibody levels. Through collaborative efforts, a comprehensive COVID-19 test to detect SARS-CoV-2 viral RNA (vRNA), antigen, and host antibody (IgG, IgM, and IgA) was developed, outperforming existing authorized antigen tests with 7-times enhanced limit of detection. This test can detect active infection and level of antibodies in protective immunity to provide pandemic surveillance and guide vaccine development. Driven by the technological advancements, the EFIRM platform was applied toward early detection of an autoimmune disease, primary Sj�gren’s syndrome (pSS). pSS diagnosis is complex and often delayed by 3-5 years. With correlation of antibody level in serum and saliva, we hypothesized that saliva autoantibody (anti-SSA/Ro-52) can be detected in pSS and its disease precursor as clinical manifestations often begins with dry mouth and dry eyes (sicca symptoms). A highly sensitive anti-SSA/Ro-52 immunoassay was developed to detect anti-SSA/Ro-52 in 80% of pSS and 60% non-pSS sicca seronegative cohorts. Our findings suggest that the proposed EFIRM assays can improve early and accurate diagnosis of COVID-19 and primary Sj�gren’s syndrome. Future works in developing multiplex capability and point-of-care modalities are of top priorities.