Nav: Home

New knowledge on the development of asthma

June 26, 2019

Researchers at Karolinska Institutet in Sweden have studied which genes are expressed in overactive immune cells in mice with asthma-like inflammation of the airways. Their results, which are published in the journal Immunity, suggest that the synthesis and breakdown of fats plays an important part in the process.

The job of the human immune system is to read our environment and react to potentially harmful substances. In asthma, the immune system is overactive, causing inflammation in the lungs and symptoms such as coughing, wheezing and shortness of breath.

A kind of immune T cell called a Th2 cell plays a vital part in asthma-related inflammation, but the rarity of these cells and a lack of sensitivity technology has made these cells hard to study in any detail.

Researchers at Karolinska Institutet have now used a highly sensitive technique called single-cell RNA sequencing to analyse which genes are active in individual T cells. For the study, the team exposed mice to house dust mites, a common allergen to which most asthmatics are sensitive and which induces asthma-like lung inflammation. They then monitored gene expression in T cells before and after exposure to the allergens in the lymph glands to the point of inflammation in the lungs.

They found that in the mouse lung, the T cells express a unique profile of hundreds of genes, many of which are linked to how the cells make and break down fat. When they then gave mice a drug to block fat metabolism, the lung inflammation decreased relative to controls.

"Our results suggest that fats can help to aggravate the T-cell activated inflammation in the lungs that is seen in asthma," says the study's corresponding author Jonathan Coquet, researcher at the Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet. "We now plan to systematically test the importance of the hundreds of uniquely expressed genes in order to find those that can trigger or prevent the development of the disease."

Another feature of the study was that when T cells reached the lungs from the lymph glands, they received signals that switched on the production of two powerful inflammatory substances: the cytokines interleukin 5 and 13. These cytokines are responsible for many of our normal asthma symptoms, such as respiratory tract inflammation, muscle contraction and mucus discharge.

"Our observation is that the T cells change a great deal over time and seem to undergo a kind of reprogramming in the lungs that makes them highly inflammatory," says Dr Coquet.
-end-
The study was financed by grants from the Swedish Research Council, the Åke Wiberg Foundation and the Ollie and Elof Ericssons Foundation. The authors have declared no potential conflicts of interest.

Publication: "Single-Cell RNA Sequencing of the T Helper Cell Response to House Dust Mites Defines a Distinct Gene Expression Signature in Airway Th2 Cells". Christopher Andrew Tibbitt, Julian Mario Stark, Liesbet Martens, Junjie Ma, Jeff Eron Mold, Kim Deswarte, Ganna Oliynyk, Xiaogang Feng, Bart Norbert Lambrecht, Pieter De Bleser, Susanne Nylén, Hamida Hammad, Marie Arsenian Henriksson, Yvan Saeys and Jonathan Marie Coquet. Immunity, online 20 June 2019, doi: 10.1016/j.immuni.2019.05.014.

Karolinska Institutet

Related Asthma Articles:

Physics vs. asthma
A research team from the MIPT Center for Molecular Mechanisms of Aging and Age-Related Diseases has collaborated with colleagues from the U.S., Canada, France, and Germany to determine the spatial structure of the CysLT1 receptor.
New knowledge on the development of asthma
Researchers at Karolinska Institutet in Sweden have studied which genes are expressed in overactive immune cells in mice with asthma-like inflammation of the airways.
Eating fish may help prevent asthma
A scientist from James Cook University in Australia says an innovative study has revealed new evidence that eating fish can help prevent asthma.
Academic performance of urban children with asthma worse than peers without asthma
A new study published in Annals of Allergy, Asthma and Immunology shows urban children with poorly controlled asthma, particularly those who are ethnic minorities, also suffer academically.
Asthma Controller Step Down Yardstick -- treatment guidance for when asthma improves
The focus for asthma treatment is often stepping up treatment, but clinicians need to know how to step down therapy when symptoms improve.
Asthma management tools improve asthma control and reduce hospital visits
A set of comprehensive asthma management tools helps decrease asthma-related visits to the emergency department, urgent care or hospital and improves patients' asthma control.
Asthma linked to infertility but not among women taking regular asthma preventers
Women with asthma who only use short-acting asthma relievers take longer to become pregnant than other women, according to research published in the European Respiratory Journal.
What are the best ways to diagnose and manage asthma?
A team of experts from The University of Texas Medical Branch at Galveston examined the current information available from many different sources on diagnosing and managing mild to moderate asthma in adults and summarized them.
Insomnia prevalent in patients with asthma
A team of researchers from the University of Pittsburgh has found that insomnia is highly prevalent in adults with asthma and is also associated with worse asthma control, depression and anxiety symptoms and other quality of life and health issues.
Test used to diagnose asthma may not be accurate
A new study urges caution in the use of the mannitol challenge test for asthma in non-clinical settings.
More Asthma News and Asthma Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

Risk
Why do we revere risk-takers, even when their actions terrify us? Why are some better at taking risks than others? This hour, TED speakers explore the alluring, dangerous, and calculated sides of risk. Guests include professional rock climber Alex Honnold, economist Mariana Mazzucato, psychology researcher Kashfia Rahman, structural engineer and bridge designer Ian Firth, and risk intelligence expert Dylan Evans.
Now Playing: Science for the People

#540 Specialize? Or Generalize?
Ever been called a "jack of all trades, master of none"? The world loves to elevate specialists, people who drill deep into a single topic. Those people are great. But there's a place for generalists too, argues David Epstein. Jacks of all trades are often more successful than specialists. And he's got science to back it up. We talk with Epstein about his latest book, "Range: Why Generalists Triumph in a Specialized World".
Now Playing: Radiolab

Dolly Parton's America: Neon Moss
Today on Radiolab, we're bringing you the fourth episode of Jad's special series, Dolly Parton's America. In this episode, Jad goes back up the mountain to visit Dolly's actual Tennessee mountain home, where she tells stories about her first trips out of the holler. Back on the mountaintop, standing under the rain by the Little Pigeon River, the trip triggers memories of Jad's first visit to his father's childhood home, and opens the gateway to dizzying stories of music and migration. Support Radiolab today at Radiolab.org/donate.