HYDERABAD: Scientists at the CSIR-Centre for Cellular and Molecular Biology (CCMB), Hyderabad, have discovered how a human cell protein detects viral genetic material and activates the body’s immune response, opening up possibilities for developing broad-spectrum antiviral therapies.
The study, published in The EMBO Journal, identifies a protein called DZIP3 that acts as an early-warning sensor for viral infections and activates the cellular machinery that fights them. The research was led by Dr Santosh Chauhan’s group at CCMB.
“When a virus enters a human cell, the body’s defence system must identify the invading pathogen and activate an immune response before the virus multiplies. About seven years ago, we hypothesised that a specialised group of human proteins could perform two functions — detect viral genetic material and activate key cellular proteins to trigger an immune response,” Dr Santosh, lead author of the study, told TNIE.
The study establishes that DZIP3 performs both functions. On detecting viral RNA, the protein undergoes a structural change that activates it. It then moves to the mitochondria, where it tags and activates key immune defence proteins.
This triggers the production of Type-I interferons, signalling molecules that restrict viral multiplication. The researchers found that this pathway protects against several viruses, including SARS-CoV-2, which causes Covid-19, chikungunya and Japanese encephalitis.
The team is developing small-molecule drug candidates to enhance DZIP3 activity and strengthen the body’s natural antiviral defences. “Discovering how DZIP3 senses viral RNA and directly triggers the cell’s immune machinery gives us a deeper understanding of human immunity,” said Dr Santosh Chauhan, senior principal scientist at CSIR-CCMB.
“Uncovering these natural cell defence mechanisms opens up exciting new possibilities, and targeting DZIP3 with small molecules could lead to broad-spectrum antiviral therapies against emerging viral threats,” he said.
Dr Rinku Sahu was the study’s first author. The research involved national and international collaborators and was funded by the Department of Biotechnology, Government of India.
The findings advance understanding of how human cells recognise viruses and activate innate immunity. However, the proposed therapies remain under development and require further research to establish their safety and effectiveness.