Researchers from Kimmel Cancer Centre at Jefferson have identified a key protein that regulates inflammation and cell death.
They have discovered a protein called AIM2 that detect and reacts to dangerous cytoplasmic DNA produced by viral or microbial pathogens.
Lead researcher Emad Alnemri, Ph.D., professor of Biochemistry and Molecular Biology showed that when cells are infected with pathogens, the protein detects pathogen's DNA in the cytoplasm and attaches to the foreign DNA, thus causing a rapid inflammatory reaction that sends a signal alerting the body to the invading pathogen.
When AIM2 binds to the foreign DNA, it triggers cytoplasmic protein called ASC, which along with the AIM2 activates the production of interleukin1beta and other inflammatory cytokines that cause inflammation.
"Researchers have long sought this elusive protein that senses the presence of DNA in the cytoplasm, which is associated with pathogenic infection or the escape of undigested self-DNA into the cytoplasm," Nature quoted Dr. Alnemri as saying.
"We not only identified the key protein in this process, but also discovered how this protein reacts to DNA and causes inflammation.
"The inflammatory response triggered when AIM2 binds to foreign DNA in the cytoplasm is the body's way of alerting other systems that there is a danger present in the cell," Alnemri added.
The study also showed that AIM2 also leads to death of the infected cells, which removes the damaged cells from the body.
This inhibits the pathogen from replicating in the cells and spreading to other parts of the body.
AIM2 might work as a tumour suppressor, by killing cells with damaged DNA before they transform into cancers.
"The discovery and understanding of the AIM2 inflammasome should enable scientists to design novel therapeutics that modulate its activity," Dr. Alnemri said.
"Such therapeutics may be useful for the treatment of nucleic acid-dependent pathogenic and autoimmune diseases, such as arthritis and systemic lupus erythematosus," Dr. Alnemri added.
The study has been published in the journal Nature.