WASHINGTON: RNA molecules that stimulate the initial antivirus defense system of the body can provide protection against various SARS-COV-2 variants, including Delta, according to a study conducted on mice.
Ribonucleeat acid (RNA) is a single stranded molecule that is important in various biological roles and gene expression.
Researchers at the Yale School of Medicine in the US noted that molecules can lead to new care for Covid-19 in immunocompromised patients.
This study, published recently in the Journal of Experimental Medicine (JEM), can also provide cheap therapeutic choices for many developing countries which currently lack access to vaccines.
This study was conducted before Omicron was identified and did not test the variant behind the current surge in the case of Covid-19 in many countries.
The researchers noted that the vaccine against SARS-COV-2 was very effective in preventing disease and severe death.
However, the availability of vaccines is very limited in many low-income countries, and virus strains that resistant vaccines also appear, they said.
“This is why, in addition to the use of vaccines in preventing Covid-19, efforts are required to develop effective therapeutics against SARS-COV-2,” said Akiko Iwasaki, a professor at the Yale School of Medicine.
The body’s first defense line against SARS-COV-2 – before the involvement of antibodies and T cells – is estimated to depend on receptor molecules such as rig-i.
These molecules recognize viral genetic materials and induce customized protein production known as Interferon type I.
This interferon promotes protein production that can inhibit viral reproduction and stimulate the recruitment of immune cells to fight infection, the researchers said.
Several studies have suggested that the initial and powerful interferon production protects against Covid-19, while delayed production is associated with severe illness.
The clinical trial has shown that caring for Covid-19 patients with pure interferon proteins earlier during the disease can reduce mortality, but the interferon manufacturing is very expensive.
Recent studies show cheaper choices in the form of short RNA molecules that mimic the genetic material of SARS-COV-2 and activate RIG-I receptors to stimulate the production of interferon type I by their own body cells.
The researchers tested their approach to mice that were susceptible to SARS-COV-2 infection.
The single dose of the RNA molecule named SLR14 is enough to protect mice from severe diseases and death, especially if treatment is provided shortly before or immediately after being exposed to the virus, the researchers said.
When given shortly after viral infection, SLR14 is more effective than taking care of mice with pure interferon proteins, they said.
SLR14 MICE is protected from all SARS-COV-2 variants that appear, including Delta.
The researchers tested SLR14 in immunocompromised mice that were chronicly infected with SARS-COV-2.
RNA molecules can fully clean the viruses of these animals, even though they lack T cells and antibodies produce cell B.
The researchers note that RNA molecules such as SLR14 are relatively cheap and easy to produce.
“SLR14 because it accommodates a big promise as a new class of RNA therapy that can be applied as an antivirus against SARS-COV-2,” added Iwasaki.