From Viral Outbreak to Vaccine Development: Our Top 10 Most Viewed Blog Posts of 2020

This illustration, created at the Centers for Disease Control and Prevention (CDC), reveals ultrastructural morphology exhibited by coronaviruses. Photo Credit:  Alissa Eckert, MS; Dan Higgins, MAM CDC It is one is used in several of our top 10 most viewed blogs of 2020
Illustration from CDC; Photo Credit: Alissa Eckert, MS; Dan Higgins, MAM

When you look at our top 10 most viewed blog posts of 2020, there’s no surprise that all relate to COVID-19. We have come a long way since the beginning of the year, thanks to tireless scientists and researchers around the globe. They have led the way in COVID-19 research, treatment, and testing. Let’s take a closer look at this top 10 list:

10. Tips to Maintain Physical Distance in the Lab 

The spread of COVID-19 forced us to adapt and adjust to new ways in life, in work, and for this blog post, in the lab. In response to the pandemic, some labs shut down completely. Others have stayed open, especially those involving coronavirus research. This post provides 10 helpful distancing tips for researchers to stay safe and productive while working in the lab.  

9. Investigation of Remdesivir as a Possible Treatment for SARS-2-CoV (2019 nCoV) 

Scientists have worked hard to determine possible treatment for COVID-19. This blog post focuses on Remdesivir (RDV or GS-5734), an encouraging treatment used for the first case in the United States. It provides an in-depth look at numerous studies and clinical trials on Remdesivir as treatment for COVID-19. One key finding is that RDV needed to be administered either before or shortly after infection to limit lung damage. 

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Choices for Measuring Luciferase-Tagged Reporter Pseudotyped Viral Particles in Coronavirus Research

Coronavirus (CoV) researchers are working quickly to understand the entry of SARS-CoV-2 into cells. The Spike or S proteins on the surface of a CoV is trimer. The monomer is composed of an S1 and S2 domain. The division of S1 and S2 happens in the virus producing cell through a furin cleavage site between the two domains. The trimer binds to cell surface proteins. In the case of the SARS-CoV, the receptor is angiotensin converting enzyme 2. (ACE2). The MERS-CoV utilizes the cell-surface dipeptidyl peptidase IV protein. SARS-CoV-2 uses ACE2 as well. Internalized S protein goes though a second cleavage by a host cell protease, near the S1/S2 cleavage site called S2′, which leads to a drastic change in conformation thought to facilitate membrane fusion and entry of the virus into the cell (1).  

CDC / Alissa Eckert, MS; Dan Higgins, MAMS

Rather than work directly with the virus, researchers have chosen to make pseudotyped viral particles. Pseudotyped viral particles contain the envelope proteins of a well-known parent virus (e.g., vesicular stomatitis virus) with the native host cell binding protein (e.g., glycoprotein G) exchanged for the host cell binding protein (S protein) of the virus under investigation. The pseudotyped viral particle typically carries a reporter plasmid, most commonly firefly luciferase (FLuc), with the necessary genetic elements to be packaged in the particle. 

To create the pseudotyped viral particle, plasmids or RNA alone are transfected into cells and the pseudotyped viruses work their way through the endoplasmic reticulum and golgi to bud from the cells into the culture medium. The pseudoviruses are used to study the process of viral entry via the exchanged protein from the virus of interest. Entry is monitored through assay of the reporter. The reporter could be a luciferase or a fluorescent protein.   

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