Home / Science / Health /  How Covid evades human immune defence system? Study explains key reasons
Listen to this article

Coronavirus can evade human immune defence system, a new study has identified and further stated that this fact “might help to explain why the pandemic has been so severe". 

SARS-CoV-2 can knock out an important molecular pathway linked to an immune complex called MHC class I, research published in the 'Nature Communications Journal' pointed out. 

MHC (major histocompatibility complex) class I molecules are a central weapon in the immune response against viruses. When a virus infects a cell, the cell facilitates the expression of viral antigens on the surface of infected cells, drawing the attention of immune cells called cytotoxic T cells. These immune cells zero in on and destroy the infected cells, together with the invading virus inside them.

Hokkaido University and Texas A&M University immunologist Koichi Kobayashi, who led the study, pointed out, "Our discovery reveals how the virus can evade the human immune defence system and might help to explain why the pandemic has been so severe." 

"The mechanisms we identify may provide new molecular targets for drug discovery," Kobayashi further added.

The scientists used a bioinformatics approach to look at how SARS-CoV-2, the virus that causes COVID-19, changed gene expression in the immune systems of COVID-19 patients compared to uninfected individuals. This is a useful way to look into the function of complicated cell signalling pathways that trigger immune responses to fight off harmful bacteria and viruses.

Apart from SARS-CoV-2 virus, HIV and MERS viruses also target the MHC class I pathway. Researchers were aware that SARS-CoV-2 probably did the same, but this study is the first to unravel the mechanism.

"Without the activation of the MHC class I pathway, viruses in the infected cells are essentially hidden from the immune system. That helps to explain why SARS-CoV-2 virus persists in the body and why it keeps infecting others, leading to the pandemic," Kobayashi said.

Subscribe to Mint Newsletters
* Enter a valid email
* Thank you for subscribing to our newsletter.
Recommended For You
Edit Profile
Get alerts on WhatsApp
Set Preferences My ReadsFeedbackRedeem a Gift CardLogout