CSIR-CCMB Study Identifies Human Body’s Defence Against Viruses
Researchers plan to develop small-molecule drug candidates to enhance defence activity
Human cells have a previously unidentified defence mechanism that detects viral genetic material and activates an immune response to prevent viruses from multiplying, scientists at the CSIR-Centre for Cellular and Molecular Biology (CCMB), Hyderabad, have found.
The researchers identified a protein called DZIP3 that acts as an early-warning sensor for viral infections and activates key immune defence proteins, triggering the production of type-I interferons, molecules that help stop viruses from multiplying inside cells.
The study, led by senior principal scientist Dr Santosh Chauhan, has been published in The EMBO Journal. The findings could help researchers develop potential broad-spectrum antiviral therapies against multiple viruses.
The team demonstrated that the DZIP3-mediated pathway provides protection against several disease-causing viruses, including SARS-CoV-2, which causes Covid-19, chikungunya and Japanese encephalitis.
When a virus enters a cell, the body's defence system must recognise the invading pathogen before it can multiply and spread. The researchers found that DZIP3 detects viral RNA inside the cell and changes its shape to activate itself.
Once activated, the study said the protein moves to the mitochondria, the energy-producing structures inside cells, where it tags and activates key immune defence proteins. This sets off a chain of reactions that stimulates the production of type-I interferons, which help restrict viral multiplication.
The discovery builds on a hypothesis proposed by Dr Chauhan's group about seven years ago that certain human proteins could perform two functions: detect viral genetic material and activate the cellular machinery responsible for mounting an immune response.
The researchers are now developing small-molecule drug candidates that could target and enhance DZIP3 activity, with the aim of strengthening 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," Dr Chauhan said.
He said understanding these natural defence mechanisms could open up possibilities for developing broad-spectrum antiviral therapies against emerging viral threats. Dr Rinku Sahu was the first author of the study, which involved collaborators from national and international institutions. The research was funded by the Department of Biotechnology, Government of India.
