If you're suffering through a cold as you read this, with all the mucus, throbbing of temples and listlessness that come with it, let a new study cheer you up: Researchers have created the first mice susceptible to the one of the most common human cold viruses, bringing the world a step closer to a cure—or at least a better understanding of the disease that costs Americans an estimated $40 billion and 22 million missed school days a year.
Researchers have struggled to create an animal model of the common cold because they cannot get the usual lab animals to succumb to rhinovirus, the pathogen that causes 30 to 35 percent of all colds, according to the National Institutes of Health. “This has been a major obstacle to developing new treatments, and there is currently no effective treatment for rhinovirus infection," researcher Sebastian Johnson of Imperial College London said in a statement.
Mice, for example, lack the right cellular backdoor to grant entry to rhinovirus, which typically infects cells lining the airway by latching on to the surface protein, intercellular adhesion molecule-1 (ICAM-1). But the protein is shaped differently in rodents than it is in people.
To solve that problem, Sebastian and co-workers engineered mice to contain the human form of ICAM-1 or that of a second protein receptor recognized by about 10 percent of cold-causing rhinoviruses. When exposed to rhinovirus, the transgenic mice suffered from inflamed airways and excess mucus, along with increased production of immune system molecules characteristic of human rhinovirus infections, the group reports in a study published online this week in Nature Medicine.