'Key' to immunising herpes, common cold found

Toronto: Scientists have discovered a critical step in the immune system's recognition of DNA viruses, an advance that may lead to vaccinations for herpes, the common cold or even cancer.

A new study found that a protein, previously known to be involved in metabolism, is critical for the detection of the viruses. The discovery is a significant advancement towards the development of vaccines for DNA viruses such as herpes and colds, researchers said.

"We have identified an important step in the detection of DNA viruses by the immune system, and have shown that this is absolutely crucial in the response to a vaccine against these infections," said Brian Lichty from McMaster University in Canada.

"If the key immune system component identified in these studies is not triggered, then vaccination fails," said Lichty. This study could have further impact on a number of serious conditions and illnesses, researchers said.
"This represents a breakthrough in our fundamental understanding of how our immune system detects a viral infection," said Yonghong Wan from McMaster University.

"But it goes beyond that, as this component of our immune system is also involved in detection of cancer by our immune system and is central to the development of autoimmune diseases," Wan said.

"So this discovery potentially impacts anyone infected by a virus, receiving a vaccination, fighting cancer or experiencing autoimmunity," he added. Prior to the study, it was known that interferon regulatory factor-3 (IRF-3), a protein coding gene, contributed to a first line of defense against viral infection
by triggering antiviral activity.

However the activation of IRF-3 following infection was not fully understood.
The study found that an interaction with the protein S6K1 and the signalling adaptor STING is a fundamental regulatory mechanism for IRF3 and, thus, helps trigger antiviral responses.

"Now that we have identified this aspect of the immune system, we can work on developing methods to engage this pathway during vaccination against viruses or cancer," Lichty added. The findings were published in the journal Nature Immunology.