Scientists find asthma vaccine in mite gene

Date accessed: 02 August 2001

Reuters News Agency

July 4, 2001

Singapore — Singapore scientists have created a vaccine which could prevent millions of children from developing asthma - by using a gene from the dust mite.

The tiny creatures are one of the most common causes of allergic reactions leading to asthma in children, associate professor Chua Kaw Yan of the National University of Singapore told Reuters on Wednesday.

"We use this piece of gene to educate the immune system of the susceptible host to tell it to not develop any bad reaction," she said.

By halting the allergic reaction, the vaccine eradicates the chance of a child developing asthma -- a major step forward since there is currently no way of preventing its onset.

"It is the world's first genetic vaccine for the prevention of allergic asthma. The strategy is novel," Ms. Chua said.

Children may grow out of the disorder but asthma often continues into adulthood. Severe attacks can lead to patients suffocating to death as their air passageways constrict.

According to World Health Organization estimates, between 100 million and 150 million people worldwide suffer from asthma. The numbers have been rising steadily.

In Australia and Singapore, between 15 and 20 per cent of young children are estimated to be affected by asthma.

Doctors can temporarily treat the symptoms with drugs such as steroids. But they suppress the body's overall immune system and can affect a child's growth.

Another longer-term way to control asthma is to desensitise the body to the triggering allergens with a course of about 70 injections over three years.

But the technique, known as desensitisation immunotherapy, is costly, time-consuming, painful and not readily available in Southeast Asia, Ms. Chua said.

Ms. Chua and her team have completed successful studies of the vaccine on rats and mice and have been granted a U.S. patent.

The team is now looking for commercial partners to begin human clinical trials in the United States and believe that the genetic vaccine, administered as a single injection, will be most effective when used on children under the age of one.

Category: 32. Genome Project and Genomics