Immune System Cells May Be Cause of Asthma

United Pro Smoker's Newsletter ^ | 03.15.06

[SheLion]

WEDNESDAY, March 15 (HealthDay News) -- As medical technologies improve, researchers are rooting out more information about possible causes of common diseases, such as asthma.

One new finding, reported in the March 16 issue of the New England Journal of Medicine, is that immune system cells long thought to cause asthma may not be the primary culprit behind the disease.

"We found that asthma is caused not by T-helper 2 cells as has been previously thought, but by a novel class of cells called natural killer T cells," said one of the study's authors, Dr. Dale Umetsu, a professor of pediatrics at Harvard Medical School and Children's Hospital Boston, and a visiting professor at Stanford University in California.

"The majority of T cells in people with asthma aren't what we thought they were," he added.

According to Umetsu, natural killer T cells were only recently discovered because the technology to differentiate these cells from others hasn't been around long.

T cells are a part of the body's immune defenses and normally help rid the body of foreign invaders, such as viruses or bacteria. In asthma, however, the immune cells don't work as they should and instead produce inflammation in the lungs.

More than 20 million Americans have been diagnosed with asthma, according to the U.S. Centers for Disease Control and Prevention, and about 4,200 people die from the disease each year.

Asthma symptoms include wheezing, coughing, breathing difficulties and a feeling of tightness in the chest. While the exact cause of the disease is unknown, doctors do know that asthma can be exacerbated by exposure to certain triggers, such as dust mites, pollen, pets and even exercise or cold air. There is no cure for asthma, only treatments aimed at managing it.

Because studies in mice uncovered the presence of natural killer T cells only in rodents with asthma, the researchers behind the new study compared samples from 14 people with asthma to samples from six healthy "controls" and five people with another inflammatory lung disorder called sarcoidosis, which is unrelated to asthma.

About 60 percent of the T cells in the asthma group were natural killer T cells, not the expected helper T cells. No natural killer T cells were evident in samples from the healthy control group or the people with sarcoidosis.

"These were very surprising findings -- a turn of events that no one suspected in the past," said Umetsu. "Part of the reason they escaped notice is they have many features that are similar to T helper 2 cells. Now, we need to know more about the biology of natural killer T cells to develop more specific therapies for asthma."

"None of the current [asthma] therapies are focused on targeting natural killer T cells. Perhaps as we develop therapies that can eliminate them from the lungs, we could have more effective and possibly curative therapies for asthma," he said.

The first step, however, is to confirm these findings in a larger group of people, and in a more diverse population of people with asthma, because there are different types of asthma. Some people have asthma that's triggered by allergens, while for others exercise or cold air can induce airway spasms.

Also, Umetsu said that researchers have to learn more about how these cells work and what causes them to go to the lungs initially. Natural killer T cells appear to respond to different things than helper T cells.

Any potential therapy would have to specifically target the lungs because natural killer T cells do have some protective effects in the rest of the body, he added.

Dr. Jonathan Field, director of the allergy and asthma clinic at New York University Medical Center/Bellevue in New York City, said, "This may be a new paradigm of how people develop asthma."

But, he cautioned that more needs to be learned about these cells, such as whether they are the actual cause of disease or if they simply appear in response to the disease.

"You have to wonder which [immune cells] actually are causing the most pathology," Field said. "Are natural killer T cells causing the changes? Which cell is the conductor and which is the actual locomotive?"    

[surrey]

Don't have a cat, never did and am never around them. As far as the oak, it's the trees not the wooden furniture.

Yes, Pulmicort is very pricey but it's worth every penny.

[MamaLucci]

Right, but my understanding of so called autoimmune disorders is that an initial trigger, such as a common virus or bacteria, can set off such a reponse. The immune response does not end, even though the initial "invader" has been defeated.

[MamaLucci]

I tend to agree with you.......something is causing the huge increase in these disorders.

[I'm ALL Right!]

Yes, but there are new kinds of chemicals that haven't always been around since the beginning of time. We are being exposed to something more frequently than we were before. I don't think it's one specific kind of chemical. I think it is the combination of them all that is causing problems.

[SheLion]

You do not have "adult-onset" asthma but an extrinsic asthma brought on by the cats allergens. I cannot get rid of my daughter's cat so i will suffer for a few more years (the cat always finds its way back to the house...>1 mile and counting).

If you can get rid of the cat your asthma should go away.

Did you mean to post this to me?  I don't have asthma but I do have a cat. :)

[SheLion]

Pulmicort is an inhaler. And you bet I'm relieved. I had reached the point where I was uneasy about travel. The thought of being on a plane and possibly having an episode was terrifying.
I have to remind myself every day not to leave the house with my rescue inhaler ,just in case..

I can imagine.  I was addicted to Dristan Nasal Spray for over 5 years and I would panic if I left the house without one.

So I can imagine what a horrible feeling it would be if you didn't have your inhaler. 

[PissAndVinegar]

The irony here is that I've seen studies that indicate children raised around animals, tend to have less incidences of asthma.

Not sure if it's related but it plays into the theory that your immune system needs to be 'exercised' to work properly. Kids raised in sterile environments usually get their butts kicked by a simple cold. The immune system needs exercise so it know when to attack and to hit hard.

Conversely, with 'exercise' it can learn what NOT to attack, what's not a real threat (like pollen and dander) thereby helping minimize allergies (and possibly other autoimmune disorders).

[metesky]

Whiners often claim that SHS "triggers" asthma attacks.

[MinorityRepublican]

I think the more common use of chemicals in everything including food, lotions, shampoos, make-up, laundry detergent, milk, etc has contributed to the rapid increase in these kinds of conditions, cancer included.

What sort of chemicals exactly? Elaborate plaese.

Your premise is right, however. There is something unnatural about the environment we live in. And yes, I am a mild sufferer of Asthma.

It would be interesting to see how many FReepers here are diagnosed with asthma.

[Gone GF]

People I know who have asthma don't claim that tobacco smoke "causes" or even triggers asthma. To a person (including my sister and niece) they do claim that smoke makes breathing harder if they're having trouble.

[Ladysmith]

Hear, hear. I'm with you on that. The more fragrance-free or organic products I'm finding, the better I'm getting. The second I'm around someone or something loaded with fragrance, I'm about down for the count.

[SheLion]

Not sure if it's related but it plays into the theory that your immune system needs to be 'exercised' to work properly. Kids raised in sterile environments usually get their butts kicked by a simple cold. The immune system needs exercise so it know when to attack and to hit hard.

Conversely, with 'exercise' it can learn what NOT to attack, what's not a real threat (like pollen and dander) thereby helping minimize allergies (and possibly other autoimmune disorders).

That is exactly right.  Kids today are being too well protected from life and sports and the environment.  They need to grow up with all this stuff in order for their immune systems to grow and be able to fight off infections.  I agree one hundred percent.

[SheLion]

Whiners often claim that SHS "triggers" asthma attacks.

hehe!  I know!  :)

Quite a few of them are in FR too.  I know how they spew that shs triggers their attacks.  One reason I posted this, because there is nothing in this research that even mentions cigarettes or second hand smoke.

[Mears]

"I sure don't know if you can outgrow asthma or not."

---

I outgrew asthma.

I had it from age 5 to age 21. I could barely climb a single flight of stairs when I had a attack,I slept seated in a chair,I'd lose weight and I was very thin.

At 21 I had a bad attack and I couldn't even walk to the bus stop---I would take a cab to the school where I was teaching.It lasted for 2 miserable weeks.

I never had another attack in the next fifty years.It just stopped.

I am convinced that a good cup of strong,black coffee helps asthmatics and smoking certainly did me no harm since I still smoke.

Coffee and cigars were some of the treatments given to Teddy Roosevelt,who had severe asthma, and TR had the best doctors money can buy.

[383rr]

Thanks for the ping!

[Ditter]

SHS does trigger asthma in some of us and I am not a whiner, I'm just trying to educated you people. The article doesn't mention lots of allergens that trigger asthma but that doesn't mean those allergens aren't a problem to some people.

[Alamo-Girl]

Thanks for the ping!

[primrose]

Thank you,you hit the nail on the head.you are right.A friend of mine told me if you can't pronounce what's on the labels of foods don't eat it,could be dangerous to my health.To many young people i know have MS.THIS IS NOT GOOD...