Updated on 11 June 2014
Vaccine for SARS, MERS to soon become a reality
Singapore: A Purdue University team headed by Mr Andrew Mesecar has made a breakthrough by unraveling the mystery around how to disable a part of the SARS virus, responsible for hiding it from the immune system.
Mr Mesecar explained in a report, "This is the first step toward creating a weakened and safe virus for use in an attenuated live vaccine. This also could serve as a molecular roadmap for performing similar studies on other coronaviruses, like MERS, because this enzyme appears to be common to all viruses within this family." There is currently no treatment or vaccine for the virus, which has an estimated fatality rate of 30 percent, according to the Centers for Disease Control and Prevention.
Scientists captured the molecular structure of a key SARS enzyme, papain-like protease and revealed how it strips a host cell of the proteins ubiquitin and ISG15, which is involved in triggering an immune response.
"With most viruses, when a cell is infected it sends out an alarm triggering an immune response that fights the infection, but successful viruses are able to trick the immune system," he said. "By clipping off these two proteins, SARS short circuits the host cell's signaling pathways and prevents it from alerting the immune system to its presence. By removing these proteins, the enzyme serves as a biological cloaking system for the SARS virus that allows it to live and replicate undetected."
"The disruption in its natural signaling pathways also causes an infected cell to miscommunicate with the cells around it which leads to a response that eventually kills those cells," he said.