How dust mites can relieve asthma by re-tuning the immune system

A tablet made from a protein found in house dust mites could revolutionise the treatment of asthma.

The pill, which melts under the tongue, is designed to re-tune the immune system so that it does not over-react when it comes into contact with mite droppings, which are a leading trigger for asthma attacks.

Early trial results show patients who take the tablet every day are able to substantially reduce their use of inhaled steroids — the drug of choice for keeping asthma attacks at bay.

In a trial involving 600 asthma sufferers allergic to house dust mites, one in three on the pill were able to stop using their inhaled steroids

In a trial involving 600 asthma sufferers allergic to house dust mites, one in three on the pill were able to stop using their inhaled steroids

Around 5.2 million people in Britain have asthma. The condition can be fatal, with one person dying as a result of it every seven hours, and leaves more than 70,000 a year needing hospital treatment.

House dust mites are a leading cause of wheezing and asthma attacks.

The tiny creatures, which are related to the spider family, are less than half a millimetre long and whitish in colour. They thrive in dark, humid places at temperatures of 25c.

As they feed on dead human skin cells, they gather in mattresses, pillows, clothing, carpets, upholstered seats and even soft toys.

Their droppings contain proteins which, when inhaled or touched by someone who is allergic to them, prompts the immune system to produce antibodies that cause the large-scale release of a chemical called histamine.

It is this rush of histamine that leads to swelling and irritation of the airways, causing breathing difficulties and asthma attacks.

Sufferers who are sensitive to dust mite droppings are advised to take preventive measures including washing walls and floors with wet cloths, using plastic instead of material curtains, and even freezing cuddly toys once a month to kill off any mites they might harbour.

House dust mites feed on dead human skin cells, they gather in mattresses, pillows, clothing, carpets, upholstered seats and even soft toys

House dust mites feed on dead human skin cells, they gather in mattresses, pillows, clothing, carpets, upholstered seats and even soft toys

But a daily tablet could be more practical. It has been developed by Danish firm ALK Abello, which also made the anti-hay fever pill Grazax, made from grass pollen.

The drug contains extracts of proteins found in dust mite droppings.

This form of treatment is known as immuno-therapy and works by regularly exposing the immune system to tiny amounts of the protein.

This re-tunes the immune system so that it no longer interprets the proteins as a threat and does not trigger the histamine rush that causes asthma attacks.

In a trial involving 600 asthma sufferers allergic to house dust mites, one in three on the pill were able to stop using their inhaled steroids.

‘Ninety per cent of people with asthma tell us dust triggers their symptoms, so this research is encouraging,’ says Leanne Metcalf at Asthma UK.

‘We know some people find inhalers difficult to use, and asthma medicines can have side-effects if taken in high doses or for a long time, so we look forward to when this research can be translated into an alternative treatment.’

Meanwhile, doctors are testing a salt water spray as a treatment for another common breathing problem, bronchiolitis.

A clinical trial with 300 children under 12 months is being carried out at a number of hospitals to see if the therapy should introduced throughout the NHS.

Bronchiolitis, an infection of the lower respiratory tract, affects babies and young children. The airways become infected and swollen, making it more difficult to breathe.

One third of babies develop bronchiolitis in their first year and it’s the most common reason for children — especially those aged under six months — to be admitted to hospital. Treatment options are limited to supportive care and oxygen.

Previous research found salt water, sprayed as a mist so it can be breathed in, can help children with acute bronchiolitis.

Three small research studies have suggested that the time a child spends in hospital could be reduced by a quarter by using this treatment.