Toll-like receptors, a class of proteins sniff out bacteria and viruses and activate the body's immune system for an attack on these invaders.
One of the proteins in this class, toll-like receptor 9 or TLR9, can pick up a snippet of DNA common in bacteria and viruses called CpG DNA.
The study could help drug makers create DNA-based drugs which would get the guard dogs howling, which, in turn, would trip a fast immune response, causing the body to attack cancerous tumours or, if used as an ingredient in vaccines, bolster the assault on infectious diseases such as hepatitis B and C. CpG DNA could even be used to treat immune system disorders such as asthma and allergies.
The study was conducted by a ream of researchers led by Wen-Ming Chu at Brown University
Researchers found a direct interaction between HMGB1, (a protein released when infection occurs, when cells are damaged or when tissue is injured) and TLR9.
The study found that when the invader's DNA is present TLR9 meets up with HMGB1. The combination occurs inside tiny cellular cargo boxes, called endoplasmic reticulum-Golgi intermediate compartments (ERGIC).
Researchers noted that in ERGIC the proteins bind to form a complex that sets off a biochemical cascade, which triggers the body's immune response.
When HMGB1 is absent from cells, it was found that the body's immune response was significantly delayed.