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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.

We developed a 4-parameter clinical assay using Electric Field Induced Release and Measurement (EFIRM) technology to simultaneously assess SARS-CoV-2 RNA (vRNA), nucleocapsid antigen, host binding (BAb) and neutralizing antibody (NAb) levels from a drop of saliva with performance that equals or surpasses current EUA-approved tests. The vRNA and antigen assays achieved lower limit of detection (LOD) of 100 copies/reaction and 3.5 TCID₅₀/mL, respectively. The vRNA assay differentiated between acutely infected (n=10) and infection-naïve patients (n=33) with an AUC of 0.9818, sensitivity of 90%, and specificity of 100%. The antigen assay similarly differentiated these patient populations with an AUC of 1.000. The BAb assay detected BAbs with an LOD of 39 pg/mL and distinguished acutely infected (n=35), vaccinated with prior infection (n=13), and vaccinated infection-naïve patients (n=13) from control (n=81) with AUC of 0.9481, 1.000, and 0.9962, respectively. The NAb assay detected NAbs with an LOD of 31.6 Unit/mL and differentiated between COVID-19 recovered or vaccinated patients (n=31) and pre-pandemic controls (n=60) with an AUC 0.923, sensitivity of 87.10%, and specificity of 86.67%. Our multiparameter assay represents a significant technological advancement to simultaneously address SARS-CoV-2 infection and immunity, and it lays the foundation for tackling potential future pandemics., Competing Interests: COMPETING INTERESTS O.Y. is the scientific advisory board for CytoDyn (stock options and cash) and board of directors for Applied Medical (stock and cash). D.W. gets a consulting fee from AIONCO/Avellino and has stock options in AIONCO/Avellino. Other authors declared no conflict of interests.

The clinical spectrum of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the strain of coronavirus that caused the COVID-19 pandemic, is broad, extending from asymptomatic infection to severe immunopulmonary reactions that, if not categorized properly, may be life-threatening. Researchers rate COVID-19 patients on a scale from 1 to 8 according to the severity level of COVID-19, 1 being healthy and 8 being extremely sick, based on a multitude of factors including number of clinic visits, days since the first sign of symptoms, and more. However, there are two issues with the current state of severity level designation. Firstly, there exists variation among researchers in determining these patient scores, which may lead to improper treatment. Secondly, researchers use a variety of metrics to determine patient severity level, including metrics involving plasma collection that require invasive procedures. This project aims to remedy both issues by introducing a machine learning framework that unifies severity level designations based on noninvasive saliva biomarkers. Our results show that we can successfully use machine learning on salivaomics data to predict the severity level of COVID-19 patients, indicating the presence of viral load using saliva biomarkers., Competing Interests: Conflicts of Interest David Wong has equity in Liquid Diagnostics LLC and RNAmeTRIX.

The emergence of Omicron and Delta variants of SARS-CoV-2 has begun a number of discussions regarding breakthrough infection, waning immunity, need and timing for vaccine boosters and whether existing mRNA vaccines for the wildtype strain are adequate. Our work leverages a biosensor-based technique to evaluate the binding efficacy of SARS-CoV-2 S1 specific salivary antibodies to the Omicron and Delta variants using a cohort of mRNA vaccinated (n=109) and convalescent (n=19) subjects. We discovered a wide range of binding efficacies to the variant strains, with a mean reduction of 60.5%, 26.7%, and 14.7% in measurable signal to the Omicron strain and 13.4%, 2.4%, and âˆ'6.4% percent mean reduction to the Delta Variant for convalescent, Pfizer, and Moderna vaccinated groups respectively. This assay may be an important tool in determining susceptibility to infection or need for booster immunization as the pandemic evolves., Key Points: AMPERIAL assay developed to quantify salivary SARS-CoV-2 S1 IgG antibodies to Omicron and Delta variantsThere was a reduction in affinity to both Delta and Omicron VariantsThe reduction in affinity was more pronounced to Omicron than for Delta VariantsThere was a significant difference between IgG affinities in Individuals vaccinated with Pfizer versus Moderna Vaccines.

We used a noninvasive electrochemical quantitative assay for IgG antibodies to SARS-CoV-2 S1 in saliva to investigate the kinetics of antibody response in a community-based population who had received either the Pfizer or Moderna mRNA-based vaccines. Samples were received from a total of 97 individuals including a subset of 42 individuals who collected samples twice-weekly for 3 months or longer. In all, 840 samples were collected and analyzed. In all individuals, salivary antibody levels rose sharply in the 2-week period following their second vaccination, with peak antibody levels being at 10-20 days post-vaccination. We observed that 20%, 10% and 2.4% of individuals providing serial samples had a 90%, 95%, and 99% drop respectively from peak levels during the duration of monitoring and two patients fell to pre-vaccination levels (5%). The use of non-invasive quantitative salivary antibody measurement can allow widespread, cost-effective monitoring of vaccine response., Article Summary Line: COVID-19 antibodies were measured in saliva and 20% of vaccinated subjects experienced a 90% drop in peak antibody levels over the course of monitoring.

Amperial™ is a novel assay platform that uses immobilized antigen in a conductive polymer gel followed by an electrochemical detection. A highly specific and sensitive assay was developed to quantify levels of IgG antibodies to SARS-CoV-2 in saliva. After establishing linearity and limit of detection we established a reference range of 5 standard deviations above the mean. There were no false positives in 667 consecutive saliva samples obtained prior to 2019. Saliva was obtained from 34 patients who had recovered from documented COVID-19 or had documented positive serologies. All of the patients with symptoms severe enough to seek medical attention had positive antibody tests and 88% overall had positive results. We obtained blinded paired saliva and plasma samples from 14 individuals. The plasma was analyzed using an EUA-FDA cleared ELISA kit and the saliva was analyzed by our Amperial™ assay. All 5 samples with negative plasma titers were negative in saliva testing. Eight of the 9 positive plasma samples were positive in saliva and 1 had borderline results. A CLIA validation was performed as a laboratory developed test in a high complexity laboratory. A quantitative non-invasive saliva based SARSCoV-2 antibody test was developed and validated with sufficient specificity to be useful for population-based monitoring and monitoring of individuals following vaccination.