Washington: Scientists have constructed a three-dimensional model of the pathogen that shows why there is no cure yet for the common cold.
A team led by biochemistry Professor Ann Palmenberg from the University of Wisconsin-Madison, provides a meticulous topographical model of the capsid or protein shell of a cold virus that until 2006 was unknown to science.
The "missing link" cold virus, rhinovirus C is believed to be responsible for up to half of all childhood colds, and is a serious complicating factor for respiratory conditions such as asthma.
The A and B families of cold virus, including their three-dimensional structures, have long been known to science as they can easily be grown and studied in the lab. Rhinovirus C , on the other hand, resists culturing and escaped notice entirely until 2006 when "gene chips" and advanced gene sequencing revealed the virus had long been lurking in human cells alongside the more observable A and B virus strains.
The new cold virus model was built "in silico," drawing on advanced bioinformatics and the genetic sequences of 500 rhinovirus C genomes, which provided the three-dimensional coordinates of the viral capsid.
With a structure in hand, the likelihood that drugs can be designed to effectively thwart colds may be in the offing. Drugs that work well against the A and B strains of cold virus have been developed and advanced to clinical trials.
Because all three cold virus strains all contribute to the common cold, drug candidates failed as the surface features that permit rhinovirus C to dock with host cells and evade the immune system were unknown and different from those of rhinovirus A and B.
Holly A. Basta, the lead author of the study said that based on the new structure, they predict that researchers will have to make a C-specific drug.
The study is published in journal Virology.