There are more than 2,000 kinds of animal viruses in the world, among which only about 50 kinds can affect the human body. These viruses can bypass the body's anti-viral defence mechanism in a variety of ways.
Cells absorbing too much nutrition may be easily invaded by viruses, due to the body's reduced anti-viral defensive system. However, Chinese scientists recently found a compound capable of enhancing cells' anti-viral capability.
A research team led by Xu Pinglong from Zhejiang University discovered that cellular nutrient and density status regulate antiviral host defence.
Nutrient starvation or high cell confluence sensitize host cells for danger signals, activating cytosolic nucleic acid sensing and antiviral defence responses to the viral invasion.
Cytosolic nucleic acid sensing and antiviral defence response are very important for cells free from viral infection, and are strictly controlled by intrinsic molecules. But still, little is known regarding their regulations by extracellular signals.
After the viruses penetrate the cells, pathogenic nucleic acids are sensed in the cytosol by some receptors, of which TBK1 is central for this sensing.
Nutrient starvation or cell-cell contact can remove the inhibition of some molecules on TBK1 which act as a downstream signal mediator for inducing the expression of antiviral cytokines and a variety of interferon-stimulated genes (ISGs).
The research result was published online in journal Nature Cell Biology on March 27.
