ABSTRACT
The COVID-19 pandemic has demonstrated a clear need for high-throughput, multiplexed, and sensitive assays for detecting SARS-CoV-2 and other respiratory viruses as well as their emerging variants. Here, we present microfluidic CARMEN (mCARMEN), a cost-effective virus and variant detection platform that combines CRISPR-based diagnostics and microfluidics with a streamlined workflow for clinical use. We developed the mCARMEN respiratory virus panel (RVP) and demonstrated its diagnostic-grade performance on 533 patient specimens in an academic setting and then 166 specimens in a clinical setting. We further developed a panel to distinguish 6 SARS-CoV-2 variant lineages, including Delta and Omicron, and evaluated it on 106 patient specimens, with near-perfect concordance to sequencing-based variant classification. Lastly, we implemented a combined Cas13 and Cas12 approach that enables quantitative measurement of viral copies in samples. mCARMEN enables high-throughput surveillance of multiple viruses and variants simultaneously.
ABSTRACT
The COVID-19 pandemic, and the recent rise and widespread transmission of SARS-CoV-2 Variants of Concern (VOCs), have demonstrated the need for ubiquitous nucleic acid testing outside of centralized clinical laboratories. Here, we develop SHINEv2, a Cas13-based nucleic acid diagnostic that combines quick and ambient temperature sample processing and lyophilized reagents to greatly simplify the test procedure and assay distribution. We benchmarked a SHINEv2 assay for SARS-CoV-2 detection against state-of-the-art antigen-capture tests using 96 patient samples, demonstrating 50-fold greater sensitivity and 100% specificity. We designed SHINEv2 assays for discriminating the Alpha, Beta, Gamma and Delta VOCs, which can be read out visually using lateral flow technology. We further demonstrate that our assays can be performed without any equipment in less than 90 minutes. SHINEv2 represents an important advance towards rapid nucleic acid tests that can be performed in any location.
ABSTRACT
Among recent high profile scientific debates was the proposal that life could exist with arsenic in place of phosphorous in its nucleic acids and other biomolecules. Soon after its initial publication, scientists across diverse disciplines began to question this extraordinary claim. Using the original article, its claims, its scientific support, and the ensuing counterarguments, a two-day, active learning classroom exercise was developed focusing on the presentation, evaluation, and discussion of scientific argumentation and discourse. In this culminating assignment of a first semester biochemistry course, undergraduate students analyze the scientific support from the original research articles and then present and discuss multiple scientific rebuttals in a lively, civil classroom debate. Through this assignment, students develop a sense of skepticism, especially for the original arsenic-based life claims, and learn to clearly articulate their counterarguments with scientific support and critical reasoning. With its direct integration into first-semester biochemistry curriculum and the excitement surrounding arsenic based life, this assignment provides a robust, simple, and stimulating framework for introducing scientific discourse and active learning into the undergraduate molecular science curriculum. © 2016 by The International Union of Biochemistry and Molecular Biology, 45(1):40-45, 2017.
