Navigation Links
Allergic response tied to lipid molecules in cell membrane
Date:3/7/2008

A team of Penn State University researchers is the first to demonstrate that lipid molecules in cell membranes participate in mammals' reactions to allergens in a living cell. The finding will help scientists better understand how allergy symptoms are triggered, and could contribute to the creation of improved drugs to treat them. The work will be reported in the 14 March issue of the Journal of Biological Chemistry.

The team studied clusters of cholesterol-rich lipid molecules that they believe serve as platforms for the receptors that receive antibodies, the proteins that protect the body from allergens. In this case, the team examined IgE antibodies, which upon binding to their receptors initiate a cell's release of histamine--the substance that causes the unpleasant, but beneficial, mucous production, congestion, and itchiness associated with allergies. "This research is basically the molecular foundation for why many people sneeze in the spring," said Ahmed Heikal, an associate professor in the Department of Bioengineering and a leader of the project.

While the idea that lipid clusters--also known as lipid domains--are involved in the allergic response is not new, the Penn State team is the first to document this connection in a living cell under physiological conditions. "No one has observed the domains in action because they are too small and too transient--held together by very weak molecular interactions--to be viewed with a light microscope," said Erin Sheets, a Penn State assistant professor of chemistry who also is a leader of the project. "To overcome this challenge," added Heikal, "we used a combination of imaging and spectroscopy techniques that we are developing in our laboratories.

In their experiment, the researchers first labeled the cell membrane and IgE antibodies with two different fluorescent tags. Next, they introduced an allergen and watched as it bound to receptors on the cell membrane, thus initiating an allergic response.

But to demonstrate that this activity was taking place within the lipid domain, the researchers had to take advantage of a property of fluorescence, called fluorescence lifetime, in which molecules are excited with very short laser pulses. The length of time a molecule remains in its excited state before emitting a photon--the fluorescence lifetime--provides unique information about the fluorescently-labeled molecule's environment and its chemical structure. For example, a particular molecule might relax to its lowest-energy state quickly or slowly depending on whether it is exposed to a solvent.

"We previously showed that our fluorescently-labeled membrane probe has a longer lifetime within a cholesterol-rich lipid domain," said Sheets. "Here we show that changes in this lifetime follow the changes that occur during the first steps in the allergic response process. Our results also show that lipid domains in the cell membrane associate with IgE antibodies and their receptors in the initial stages of an allergic reaction."

In the future, Sheets and Heikal plan to apply the team's discoveries to a project involving aging. During the aging process, T cells, which protect the body from foreign substances like viruses and cancer cells, can lose their ability to signal effectively. Sheets and Heikal plan to use these fluorescence-lifetime imaging tools to examine the structure and integrity of T-cell membranes with a goal of determining why they lose their knack for signalling and how this problem can be corrected.

"We want to compare the effectiveness of signaling in young T cells, which clear out debris quickly, to old T cells, which are not as efficient," said Sheets. "I think it will be a pretty cool application of our technique."


'/>"/>

Contact: Barbara K. Kennedy
science@psu.edu
814-863-4682
Penn State
Source:Eurekalert  

Related medicine news :

1. Role seen for cannabis in helping to alleviate allergic skin disease
2. Scientists puzzled by severe allergic reaction to cancer drug in the middle Southern US
3. New Data Presented at ACAAI Informs on the Safety and Efficacy of Nasacort AQ Nasal Spray in a Trial of Children Aged 2-5 Years Old with Year-Round Allergic Rhinitis
4. Protein suppresses allergic response in mice
5. Research finds allergic children exposed to peanuts at younger ages despite recommendations to avoid
6. Allergic reactions to gadolinium-based contrast agents are rare, study finds
7. Allergic disease linked to irritable bowel syndrome
8. Allergic-like reactions occur in premedicated patients
9. U of I scientists aim to overcome allergic reactions to soy
10. Tumors use enzyme to recruit regulatory T-cells and suppress immune response
11. Study identifies key player in the bodys immune response to chronic stress
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Allergic response tied to lipid molecules in cell membrane
(Date:10/13/2017)... ... ... While it’s often important to take certain medications during the night, finding ... identified a solution. , She developed a prototype for MOTION LIGHT-UP PILL BOX to ... the need to turn on a light when taking medication during the night, allowing ...
(Date:10/13/2017)... ... 2017 , ... PurhealthRX , a leading Health and Nutrition Company, is ... to full spectrum CBD oil will revolutionize the rapidly growing CBD market by reducing ... easily incorporated into liquid products, while reducing costs to end users. , The team ...
(Date:10/13/2017)... (PRWEB) , ... October 13, 2017 , ... Apple ... care services, staged a mock evacuation of the facility as part of a disaster ... Fire Department, Echo Hose EMS and Shelton City Emergency Manager, as well as the ...
(Date:10/13/2017)... ... October 13, 2017 , ... Ellevate Network, the leading ... to advocate for action towards gender equality at their inaugural Summit in New York ... globe, and reached a social audience of over 3 million. To watch the Mobilize ...
(Date:10/13/2017)... ... October 13, 2017 , ... ... giving viewers the lowdown on sciatica in a new episode of "Success Files," ... on current events and innovation and investigates each subject in-depth with passion and ...
Breaking Medicine News(10 mins):
(Date:9/25/2017)... PROVIDENCE, R.I. , Sept. 25, 2017 /PRNewswire/ ... immunogenicity assessment, vaccine design, and immune-engineering today announced ... focused on the development of personalized therapeutic cancer ... and has provided exclusive access to enabling technologies ... MSc Eng., MBA will lead EpiVax Oncology as ...
(Date:9/19/2017)... LOUISVILLE, Ky. , Sept. 19, 2017   ZirMed ... and predictive analytics, today announced that it has been ranked ... the Black Book™ Rankings 2017 User Survey. ZirMed ... software solution for large hospitals and medical centers over 200 ... in Black Book,s healthcare technology user survey history. ...
(Date:9/12/2017)... -- Consumer reviews on the independent review site Consumer Affairs ... for hearing aids, ranking it higher than Miracle Ear ™, ... ... Hearing Aids ... store that provides high performance, state-of-the-art, German-engineered hearing aids directly to ...
Breaking Medicine Technology: