Landmark development could lead to cure for common cold virus
Researchers from the University of Wisconsin-Madison have constructed a meticulous 3-D model of a common cold virus - rhinovirus-C (HRV-C) - that explains why there is no cure. But what the researchers have accomplished is a landmark that could mean we could be closer to snuffing out the sniffles.
The virus causes upper and lower respiratory infections at the cost of more than $40 billion annually just in the United States.
This cold virus is unique
Among 3 types of cold viruses, HRV-C has a unique protein shell that is entirely different from other cold viruses.
"The question we sought to answer was how is it different and what can we do about it? We found it is indeed quite different," Professor Ann Palmenberg said in a press release.
The model structure created by the scientists explains why rhinovirus C that also causes asthma and wheezing and up to half of all colds in kids is untreatable.
The virus was an unknown contributor to respiratory infections that cause wheezing and pneumonia until recently. The virus is also a frequent cause of earaches in children.
Rhinovirus A and B are easy to study the researchers explain, but the C type had escaped notice until 2006 even though it had been hanging out with the other two viruses.
The cold virus can’t be cultured in the lab either. Scientists discovered the virus using molecular diagnostic techniques and gene sequencing. The only environment known to be conducive to growing the virus is epithelial airway cells.
In adults HRV-C has been associated with pneumonia and worsening COPD.
Not much attention had been paid to the rhinovirus in the past until the genome sequence was unlocked and it was found the virus can wreak havoc with the respiratory tract and cause more than cold symptoms.
The researchers created the detailed computer model by tapping into 500 rhinovirus genomes that yielded the three-dimensional coordinates of the virus’s protein shell.
Holly A. Basta, lead author of the study and a graduate student working with Palmenberg in the UW-Madison Institute for Molecular Virology explained: "All the [existing] drugs we tested did not work."
A cure for the cold virus would have to lock into the virus in such a way that it fits like “a piece of a jigsaw puzzle,” Basta said. Now that the structure can be studied in 3-dimensiona and in detail, pharmaceutical companies have something to work with, she added.
Antiviral drugs can’t wipe out HRV-C because they work on the surface, of the virus and the previously missing cold virus is entirely different than rhinovirus A or B or other viruses.
The finding is published Oct. 28, 2013 in the journal Virology.
One of the concerns of not understanding what can wipe out the cold virus is that it can lead to serious respiratory problems in addition to co-existing infection. You can view an image of the virus here.
It will be interesting to watch research as it unfolds. There may be a cure for the common cold on the way now that there is a model of the virus that can be studied.