Real-time SARS-CoV-2 diagnostic and variants tracking over multiple candidates using nanopore DNA sequencing

Since December 2019, the emergence of a novel coronavirus responsible for a severe acute respiratory syndrome (SARS-CoV-2) is accountable for a major pandemic situation. As consequence, a major effort worldwide has been performed for the development of viral diagnostics strategies aiming at (i) reducing the diagnostics time, (ii) decrease the costs per assay, and (iii) providing population-scale solutions. Beyond the diagnostics requirements, the description of the B.1.1.7 strain, originated in the south of England, as a highly transmissible variant has strongly accelerated the worldwide interest in tracking SARS-CoV-2 variants occurrence. Since then, other extremely infectious variants were described and unsurprisingly further others are expected to be discovered, notably due to the long period of time on which the pandemic situation is lasting. Interestingly, all currently described SARS-CoV-2 variants present systematically several mutations within the gene encoding the Spike protein, involved in host receptor recognition and entry into the cell. Hence, instead of sequencing the whole viral genome for variants tracking, our proposed strategy focuses on the SPIKE region, as a way to increase the number of candidate samples to screen at once; an essential aspect to accelerate SARS-CoV-2 diagnostics, but also improve variants emergence and progression surveillance. Herein we present a proof of concept study, for performing both at once, population-scale SARS-CoV-2 diagnostics and variants tracking. This strategy relies on (i) the use of the portable and affordable MinION DNA sequencer; (ii) a DNA barcoding strategy and a SPIKE gene-centered variants tracking, for largely increasing the number of candidates per assay; and (iii) a real-time diagnostics and variants tracking monitoring thanks to our software RETIVAD. As a whole, this strategy represents an optimal solution for addressing the current needs on SARS-CoV-2 progression surveillance, notably due to its affordable implementation, allowing its implantation even in remote places over the world.

A comprehensive review on plasmonic-based biosensors used in viral diagnostics

The proliferation and transmission of viruses has become a threat to worldwide biosecurity, as exemplified by the current COVID-19 pandemic. Early diagnosis of viral infection and disease control have always been critical. Virus detection can be achieved based on various plasmonic phenomena, including propagating surface plasmon resonance (SPR), localized SPR, surface-enhanced Raman scattering, surface-enhanced fluorescence and surface-enhanced infrared absorption spectroscopy. The present review covers all available information on plasmonic-based virus detection, and collected data on these sensors based on several parameters. These data will assist the audience in advancing research and development of a new generation of versatile virus biosensors.

Sample-to-answer COVID-19 nucleic acid testing using a low-cost centrifugal microfluidic platform with bead-based signal enhancement and smartphone read-out

With its origin estimated around December 2019 in Wuhan, China, the ongoing SARS-CoV-2 pandemic is a major global health challenge. The demand for scalable, rapid and sensitive viral diagnostics is...

Construction of Antibody Phage Libraries and Their Application in Veterinary Immunovirology

Antibody phage display (APD) technology has revolutionized the field of immunovirology with its application in viral disease diagnostics and antiviral therapy. This robust and versatile technology allows the expression of an antibody fused to a phage coat protein on the surface of a filamentous phage. The DNA sequence coding for the antibody is packaged within the phage, linking the phenotype to genotype. Antibody phage display inherits the ability to rapidly generate and modify or improve high-affinity monoclonal antibodies, rendering it indispensable in immunology. In the last two decades, phage-display-derived antibodies have been extensively used in human medicine as diagnostic and therapeutic modalities. Recently, they are also gaining significant ground in veterinary medicine. Even though these advancements are mainly biased towards economically important animals such as chicken, cattle, and pigs, they are laying the foundation of fulfilling the unmet needs of veterinary medicine as antibody-based biologics in viral diagnostics, therapeutics, and immunoprophylaxis. This review provides a brief overview of the construction of antibody phage libraries and their application in diagnosis, prevention, and control of infectious viral diseases in veterinary medicine in detail.