Bioluminescent and Fluorescent Reporter-Expressing Recombinant SARS-CoV-2.

Reporter-expressing recombinant severe acute respiratory syndrome coronavirus 2 (rSARS-CoV-2) represents an excellent tool to understand the biology of and ease studying viral infections in vitro and in vivo. The broad range of applications of reporter-expressing recombinant viruses is due to the facilitated expression of fluorescence or bioluminescence readouts. In this chapter, we describe a detailed protocol on the generation of rSARS-CoV-2 expressing Venus, mCherry, and NLuc that represents a valid surrogate to track viral infections.

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To compare the variants' viral loads, Yonatan Grad, an infectious-disease specialist at the Harvard T. H. Chan School of Public Health in Boston, Massachusetts, and his co-authors drew on test results of the staff members at the National Basketball Association, the organization responsible for professional basketball in North America. [...]you'd think that higher transmissibility must cause a higher viral load," he says. The volcanic island, which began to form from ash and lava expelled from an undersea volcano in early 2015, piqued the interest of researchers including James Garvin, chief scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland, because of its similarity to structures on Mars and possibly Venus.

ATeam technology for detecting early signs of viral cytopathic effect.

Adenosine 5'-triphosphate (ATP), the major energy currency of the cell, is involved in many cellular processes, including the viral life cycle, and can be used as an indicator of early signs of cytopathic effect (CPE). In this study, we demonstrated that CPE can be analyzed using an FRET-based ATP probe named ATP indicator based on Epsilon subunit for Analytical Measurements (ATeam). The results revealed that as early as 3 hr, the virus infected cells showed a significantly different Venus/cyan fluorescent protein (CFP) ratio compared to the mock-infected cells. The ATeam technology is therefore useful to determine the early signs of ATP-based CPE as early as 3 hr without morphology-based CPE by light microscopy, and enables high throughput determination of the presence of microorganisms in neglected samples stored in laboratories.