Europe South Asia Asia Pacific Americas Middle East Africa BBC Homepage World Service Education

Front Page



UK Politics







Talking Point

In Depth

On Air

Low Graphics

Wednesday, April 28, 1999 Published at 06:09 GMT 07:09 UK


Doctors have 'misunderstood' asthma

The findings could change the way asthma is treated

Doctors may have misunderstood the root cause of asthma, a scientist has said.

Dr Michael Holtzman, of the Washington University School of Medicine, said his research "will change the way people think about asthma".

His idea is that asthma is not caused by allergies, as many scientists believe, but by a faulty immune reaction in the cells lining the airways.

If confirmed, the finding could lead to new therapeutic approaches to deal with the disease.

Questioning the traditional view

Dr Holtzman's team published its findings in the Journal of Clinical Investigation.

The study focuses on the role played by epithelial cells, which line the airways into the lungs.

The traditional view of asthma holds that asthma is an allergic response, the researchers said.

In this model, an attack is caused by an allergen such as dust provoking a roving immune cell to react.

The immune cell then sends out chemical signals known as cytokines, attracting many more immune cells to the airways. This results in inflammation.

'Cells in the airway to blame'

But in Dr Holtzman's model, the static epithelial cells are to blame.

He performed research 20 years ago that suggested they perform a protective function, detecting foreign particles.

He said: "It seems that these cells are in fact specially programmed for host defence and are abnormally programmed in people with asthma."

He said many asthmatic patients do not suffer from allergies and that most patients with allergies do not develop asthma.

Immune response

His new research looked at a gene that triggers an immune response when it detects a virus.

It found that in asthma, this gene could operate even in the absence of a virus.

The researchers studied epithelial cells from healthy people, people with chronic bronchitis and people in asthma.

In the first two groups the protein that causes the gene to trigger a reaction was in a non-sensitive part of the cell, "presumably inactive".

But in 24 of the asthma patients, the protein was in the cell's nucleus, "presumably switching on genes".

Improvements for treatment

The team also considered how this finding will affect treatment.

Dr Holtzman and colleagues discovered that a virus that causes respiratory infections can prevent the guilty protein from activating genes.

They proposed that an aerosol of the virus - genetically altered so as not to damage immunity - could stop asthma

"The virus has taken advantage of us," Dr Holtzman said, "so perhaps we could take advantage of the virus."

Advanced options | Search tips

Back to top | BBC News Home | BBC Homepage | ©

Health Contents

Background Briefings
Medical notes

Relevant Stories

27 Apr 99 | Health
Asthma 'linked to obesity'

14 Apr 99 | Health
Writing tonic for chronic complaints

11 Dec 98 | Medical notes
Asthma factfile

Internet Links

National Asthma Campaign

Washington University School of Medicine

General Practitioners in Asthma Group

The BBC is not responsible for the content of external internet sites.

In this section

Disability in depth

Spotlight: Bristol inquiry

Antibiotics: A fading wonder

Mental health: An overview

Alternative medicine: A growth industry

The meningitis files

Long-term care: A special report

Aids up close

From cradle to grave

NHS reforms: A guide

NHS Performance 1999

From Special Report
NHS in crisis: Special report

British Medical Association conference '99

Royal College of Nursing conference '99