A health worker takes a nasal swab of a passenger for a coronavirus test (Photo credit: AFP)
BENGALURU: Researchers at the Indian Institute of Science (IISc), led by prof Utpal Tatu of the Department of Biochemistry have found a set of new proteins unique to Covid-19, including a key protein that suppresses our immune response to the virus.
The SARS-CoV-2 genome codes for more than 25 proteins, but only a handful of these proteins have been identified so far, IISc said.
“Studying viral proteins provides functional information which is currently not well represented. In the analysis, we detected 13 different proteins – most of them previously unidentified – from clinical samples. One such protein called Orf9b, which suppresses the host’s immune response, had been predicted, but our team provided the first evidence of its expression,” Tatu said.
Just knowing how the virus functions will not be enough, he said, adding that one needs to put it in the context of the host (humans).
“Therefore, in the third analysis, the team explored how human bodies respond to the virus by examining host proteins. They discovered as many as 441 proteins unique to Covid-19 positive patients, many of which are speculated to play a key role in the body’s immune response,” IISc said.
The proteomic (large-scale study of proteins) analyses were carried out using a technique called high resolution mass spectrometry. The team is upbeat about the potential that this method has for large-scale testing.
Proteins can be reliable markers of infections like Covid-19 because they are more abundant and stable as compared to RNA molecules on which the prevalent RT-PCR tests rely, the researchers argue.
Sheetal Tushir, a PhD student and the paper’s first author says: “The best thing we can [hope to] see in this century is the use of mass spectrometry as a basic technique for diagnostics.”
Mass spectrometry is a chemistry tool to detect proteins in a very highly sensitive manner. “It is 100% more accurate and sensitive compared to RT-PCR tests,” one of them said.