Genetically engineered mice, which can catch a cold, are scientists' new implement to find an effective cure for the scourge of the nasal passages.
Professor Sebastian Johnston, a virologist at Imperial College London, has achieved a success in infecting mice with the virus that results in the common cold.
AdvertisementHis work attains significance as this is the first time that a non-primate has caught a cold.
To date, Professor Johnston points out, only humans and chimpanzees were known to be susceptible to rhinoviruses, the main group of common cold viruses. This is one of the reasons why research into possible cures has been so slow, he adds.
The ability to infect laboratory mice with rhinoviruses means that scientists can now investigate how the virus infects an animal other than a human being.
Professor Johnston believes that this may speed up the rate at which new drugs are developed.
"Until now, it has not been possible to study rhinovirus infection in small animals. This has been a major obstacle to developing new treatments and there is currently no effective treatment for rhinovirus infection," the Independent quoted him as saying.
"Rhinoviruses are a major cause of the common cold and if you have a small animal model, it speeds up the rate of discovering new potential treatments. And rhinoviruses are not innocent viruses. They kill people in large numbers from acute asthma attacks and chronic bronchitis and emphysema," he added.
For its study, Professor Jonathan's team modified the genes of the mice so that the cells lining their respiratory systems had a human version of a "receptor protein" called ICAM-1, which rhinoviruses use to infect the cells.
"We previously found that once inside the mouse cell a rhinovirus reproduces itself as well as it does in human cells. But the virus couldn't infect the mouse cell because the receptor - which acts like a door key - wouldn't let the virus into the cell," he said.
"Now we've modified the mouse receptor so it is more like a human one. This means the virus can infect the cells of these modified mice. We found that mice with the modified receptor were susceptible to infection with a rhinovirus," he added.
The study, published in the journal Nature Medicine, may help advance the understanding of life-threatening respiratory attacks that result acute asthma, bronchitis and other serious lung infections.
Professor Johnston says that the genetically engineered mice his team has created may also help determine what happens during such more dangerous infections when the function of the lung is threatened and people can die as a result.
"This important and fundamental discovery will enable us to understand the effects rhinoviruses and common colds have on our health," said Professor Sir Leszek Borysiewicz, the chief executive of the Medical Research Council, which funded the study.
"It will open up new paths to finding treatments which have been delayed for many years and provides us with the opportunities for further breakthroughs in the future," Borysiewicz added.