Novel coronavirus structure reveals targets for vaccines and treatments

Outbreak of new virus in China novel coronavirus 2019
Outbreak of new virus in China novel coronavirus 2019

Washington DC. 03rd March 2020.  In late 2019, the first reports of an unknown respiratory infection—in some cases fatal—emerged from Wuhan, China. The source of that infection was quickly identified as a novel coronavirus, related to those that had caused outbreaks of Severe Acute Respiratory Syndrome (SARS) from 2002-2004 and Middle East Respiratory Syndrome (MERS) in 2012.

WHO declared COVID-19, a Public Health Emergency of International Concern

The World
Health Organization declared the illness resulting from the new virus,
COVID-19, a Public Health Emergency of International Concern.

By early
March 2020, the novel coronavirus—now named SARS-CoV-2—had
infected more than 90,000 people worldwide and killed at least 3,100.

Like other coronaviruses, SARS-CoV-2 particles are spherical and have proteins called spikes protruding from their surface. These spikes latch onto human cells, then undergo a structural change that allows the viral membrane to fuse with the cell membrane. The viral genes can then enter the host cell to be copied, producing more viruses. Recent work shows that, like the virus that caused the 2002 SARS outbreak, SARS-CoV-2 spikes bind to receptors on the human cell surface called angiotensin-converting enzyme 2 (ACE2).

To help
support rapid research advances, the genome sequence of the new coronavirus was
released to the public by scientists in China. A collaborative team including
scientists from Dr. Jason McLellan’s lab at the University of Texas at Austin
and the NIAID Vaccine Research Center (VRC) isolated a piece of the genome
predicted to encode for its spike protein based on sequences of related
coronaviruses.

The team
then used cultured cells to produce large quantities of the protein for
analysis.

The study
was funded in part by NIH’s National Institute of Allergy and Infectious
Diseases
(NIAID). Results were published on February 19, 2020, in
Science.

Researchers
used cryo-electron microscopy technique

The
researchers used a technique called cryo-electron microscopy to take detailed
pictures of the structure of the spike protein.

This
involves freezing virus particles and firing a stream of high-energy electrons
through the sample to create tens of thousands of images. These images are then
combined to yield a detailed 3D view of the virus.

The
researchers found that the SARS-CoV-2 spike was 10 to 20 times more likely to
bind ACE2 on human cells than the spike from the SARS virus from 2002. This may
enable SARS-CoV-2 to spread more easily from person to person than the earlier
virus.

Despite
similarities in sequence and structure between the spikes of the two viruses,
three different antibodies against the 2002 SARS virus could not successfully
bind to the SARS-CoV-2 spike protein. This suggests that potential vaccine and
antibody-based treatment strategies will need to be unique to the new virus.

“We hope
these findings will aid in the design of candidate vaccines and the development
of treatments for COVID-19,” says Dr. Barney Graham, VRC Deputy
Director.

Vaccine for COVID-19

The
researchers are currently working on vaccine candidates targeting the
SARS-CoV-2 spike protein. They also hope to use the spike protein to isolate
antibodies from people who have recovered from infection by the new
coronavirus. If produced in large quantities, such antibodies could potentially
be used to treat new infections before a vaccine is available. In addition, NIH
researchers are pursuing other approaches to treating the virus.

Source : NIH

Sharing is caring!

Advertisements

Be the first to comment on "Novel coronavirus structure reveals targets for vaccines and treatments"

This site uses Akismet to reduce spam. Learn how your comment data is processed.

shares