Cure for the common cold in sight

A groundbreaking discovery by UK scientists could pave the way for new drugs to defeat viral illnesses like the common cold.

All viruses are parasites, and live and multiply within cells, including human ones.

Until now, scientists thought that antibodies from our immune system could only fight off viral infections when the virus was outside the cell, by blocking or attacking it.

But Cambridge scientists have discovered that antibodies stay attached to viruses when they enter healthy cells.

Once inside the cell, the antibodies trigger a reaction, led by a protein called TRIM21, which pulls the virus into the cell's disposal system for unwanted material.

The entire process happens quickly, say the scientists, usually before most viruses have chance to harm the cell.

Most important of all, the scientists showed that increasing the amount of TRIM21 protein in cells makes the process more effective, suggesting new ways of making better antiviral drugs.

Future research will determine if all viruses are treated this way by the immune system.

Although some antiviral drugs are already available to help treat some viral conditions, such as HIV, viruses remain mankind's biggest killer, responsible for twice as many deaths each year as cancer, and are among the hardest of all diseases to treat.

This latest discovery by Dr Leo James and his team at the MRC Laboratory of Molecular Biology in Cambridge transforms scientific understanding of how our immune system responds to viral diseases like the common cold, "winter vomiting" and gastroenteritis.

“Doctors have plenty of antibiotics to fight bacterial infections but few antiviral drugs, he said.

"Although these are early days, and we don’t yet know whether all viruses are cleared by this mechanism, we are excited that our discoveries may open multiple avenues for developing new antiviral drugs."

Sir Greg Winter, deputy director of the MRC Laboratory of Molecular Biology, added: “Antibodies are formidable molecular war machines; it now appears that they can continue to attack viruses within cells.

"This research is not only a leap in our understanding of how and where antibodies work, but more generally in our understanding of immunity and infection.”

The findings are published online in the Proceedings of the National Academy of Sciences.

This article was published on Tue 2 November 2010