Toilet-papering over the COVID-19 cracks: old drugs for a new virus?
While shoppers fight over rolls of toilet paper, many scientists have quickly changed their research direction to better understand COVID-19 in a bid to find new drugs, or even a cure for the disease. Little is known about SARS-CoV-2, the virus that causes COVID-19 , but researchers are working hard to toilet-paper over the cracks in our COVID-19 knowledge.
Like all viruses, SARS-CoV-2 must hijack host cells to replicate (i.e. copy themselves). Viruses have been described as “a piece of bad news wrapped up in protein”, and once a host cell is found, SARS-CoV-2 injects its “piece of bad news”, in this case a single strand of RNA into the cell. The RNA contains the information to make 29 proteins which the virus uses to do various things including making new copies of itself and disguise itself from the host cell.
However, viruses can’t do this alone and rely on the help of human proteins. Identifying these human helper proteins will help understand how SARS-CoV-2 causes COVID-19, and help identify drugs which can stop SARS-CoV-2 taking over the cell.
Scientists from the University of California, San Francisco have made progress towards this. The researchers made26 of the 29 SARS-CoV-2 viral proteins in human cells and used these viral “bait” proteins to fish for human “prey” proteins that interact with the virus.This experiment identified 332 human proteins that interact with the virus. This information suggested that interactions between viral and human proteins rewire host machinery likely helping the virus to invade, camouflage itself, and replicate.
The scientists then looked for old drugs which targeted the newly-identified viral-human protein interactions. They found ~70 drugs including FDA approved drugs, drugs in clinical trials as well as preclinical drugs which may derail SARS-CoV-2 hijacking human cells. As 27 of these drugs are FDA approved, there is potential that they could be used in patients more quickly than developing a new drug from scratch. Future experiments following up these leads provides hope for an old drug helping scores of people with the new virus all over the world.
See primary paper at https://www.biorxiv.org/content/10.1101/2020.03.22.002386v1.full.pdf
Written by Luke Bonser in self isolation with a stocked cupboard of toilet paper.