The dynamicity of light-up aptamers in one-pot in vitro diagnostic assays

The direct modulation of a light-up aptamer that engenders an analyte-specific aptamer-light-up aptamer chimera is readily applicable in any diagnostic assay for a targeted detection.

Immunogenic epitope panel for accurate detection of non-cross-reactive T cell response to SARS-CoV-2

The ongoing COVID-19 pandemic calls for more effective diagnostic tools, and T cell response assessment can serve as an independent indicator of prior COVID-19 exposure while also contributing to a more comprehensive characterization of SARS-CoV-2 immunity. In this study, we systematically assessed the immunogenicity of 118 epitopes with immune cells collected from multiple cohorts of vaccinated, convalescent, and healthy unexposed and SARS-CoV-2 exposed donors. We identified seventy-five immunogenic epitopes, 24 of which were immunodominant. We further confirmed HLA restriction for 49 epitopes, and described association with more than one HLA allele for 14 of these . After excluding two cross-reactive epitopes that generated a response in pre-pandemic samples, we were left with a 73-epitope set that offers excellent diagnostic specificity without losing sensitivity compared to full-length antigens, which evoked a robust cross-reactive response. We subsequently incorporated this set of epitopes into an in vitro diagnostic 'Corona-T-test' which achieved a diagnostic accuracy of 95% in a clinical trial. When applied to a cohort of asymptomatic seronegative individuals with a history of prolonged SARS-CoV-2 exposure, this test revealed a lack of specific T cell response combined with strong cross-reactivity to full-length antigens, indicating that abortive infection had occurred in these individuals.

PP152 Epigenetic In Vitro Diagnostic Test For Early Diagnosis In Lung Cancer: An Early Assessment

IntroductionLung cancer is a leading cause of morbidity and mortality, and early diagnosis is essential for patient survival. Epigenetics is an innovative discipline that provides biomarkers to aid in early diagnosis, patient risk classification, or outcome prediction. Each type of tumor may present specific patterns of gene methylation, the analysis of which may be useful as a diagnostic tool. The aim of this study was to conduct an early assessment of novel in vitro diagnostic (IVD) tests based on the identification of DNA hypermethylation epigenetic signatures developed for the early detection of lung cancer.MethodsWe identified this technology through the Early Awareness and Alert System “SINTESIS-new technologies” of the Agencia de Evaluación de Tecnologías Sanitarias - Instituto de Salud Carlos III. A literature search of PubMed, the Trip Medical Database, the International Clinical Trials Registry Platform, ClinicalTrials.gov, and the Cochrane Central Register of Controlled Trials was conducted. Studies published up to November 2019 were reviewed.ResultsThree tests were identified. Epi proLung® analyzes the hypermethylation status of SHOX2/PTGER4 genes in blood samples using polymerase chain reaction (PCR) and showed good discrimination capacity with respect to healthy controls (area under the curve [AUC] = 0.91) and patients with non-malignant lung diseases (AUC = 0.86). The Epi proLung BL Reflex Assay® for determining the hypermethylation state of the SHOX2 gene in bronchoalveolar lavage samples by PCR had modest sensitivity (69%, 95% confidence interval [CI]: 64–75) and high specificity (96%, 95% CI: 97–100). A test in development for determining the hypermethylation state of BCAT1/CDO1/TRIM58/ZNF177 genes in aspirated or bronchoalveolar lavage samples by pyrosequencing yielded a sensitivity of 85 percent and a specificity of 81 percent, with an AUC of 0.91 at the optimal cutoff point.ConclusionsThe evidence for the three tests showed promising results in terms of diagnostic validity. However, although personalized medicine is becoming increasingly widespread in the field of cancer diagnosis, more studies are needed to evaluate the clinical utility of these diagnostic tests, either as a complementary or a screening test, and the economic impact of their use.