Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Novel therapy tested in mice could chase away cat allergies

29.03.2005


A molecule designed to block cat allergies successfully prevented allergic reactions in laboratory mice, as well as in human cells in a test tube, University of California, Los Angeles (UCLA) researchers report in the April issue of Nature Medicine, available online now. In the future, the investigators say, these promising results could lead to a new therapy not only for human cat allergies, but also possibly for severe food allergies such as those to peanuts.



The National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, funded the research. "This novel approach to treating cat allergies is encouraging news for millions of cat-allergic Americans. Moreover, these results provide proof-of-concept for using this approach to develop therapies to prevent deadly food allergy reactions as well," says NIAID Director Anthony S. Fauci, M.D.

The injectable treatment puts a brake on the release of a key chemical from cells involved in cat allergy reactions. That chemical, histamine, brings on allergy symptoms such as sneezing, wheezing, itching, watery eyes and sometimes asthma. When a cat-allergic person touches or inhales a protein found in cat saliva or dander (small scales from skin or hair), key immune system cells respond by spewing out histamine. Allergy experts estimate that 14 percent of children 6 to 19 years old are allergic to cats.


The treatment comprises a molecule that loosely tethers a feline and a human protein together. The feline end is the notorious protein (called Fel d1) found in cat dander and saliva that causes so much misery in allergy sufferers. On the other end sits a piece of human antibody (called IgG Fcƒ×1) that docks to a cell receptor that can be recruited to stop allergic reactions.

The investigators named the chimeric molecule GFD, or gamma Feline domesticus, for its human and feline parts, explains principal investigator Andrew Saxon, M.D., of UCLA. The cat allergen end of GFD binds to antibodies on the surface of the cell. The human end of GFD links to a different cell surface protein (called Fcƒ×RIIB) that interrupts the allergic response.

Dr. Saxon and his colleagues first tested GFD in blood donated by people allergic to cats. They cultured blood cells with either GFD or with a purified human antibody as a control. Then they added the cat protein that triggers allergic reactions to all the blood cell cultures.

"We measured more than 90 percent less histamine in the cultures with GFD," says Dr. Saxon. "Those results suggested that GFD successfully prevented the immune cells from reacting to cat allergen. The next step was to test GFD in mice that we had made allergic to the allergenic protein found in cat saliva and dander."

The researchers tested GFD in two different types of allergic mice. One set was genetically engineered to have human cat-allergy cell receptors. These mice were "passively allergic" to cats: they would react to cat protein only after the scientists first injected them with human allergic antibodies to cats. When these mice were then injected with cat allergen, GFD blocked the allergic reaction involving the human cell receptors, an indication that it might also work in people.

Scientists made another set of mice allergic to cats by injecting them with cat protein and an immune system booster. These mice became "actively allergic" to cats: their reactions to cat allergen would be comparable to reactions in a cat-allergic person. Scientists injected some of these mice with GFD, and then injected cat allergen into the windpipes of all the mice, including a control group that was not allergic to cats. GFD damped asthma-like and other allergic reactions in the cat-allergic mice: reactions in the mice that received GFD were similar to the control group mice that were not allergic to cats.

The molecule has the potential to prevent allergic reactions long after injections cease, Dr. Saxon says. However, further research and clinical testing would be required before it might be used in humans. He also is interested in applying this approach to develop a preventive treatment for serious food allergies.

NIAID is a component of the National Institutes of Health, an agency of the U.S. Department of Health and Human Services. NIAID supports basic and applied research to prevent, diagnose and treat infectious diseases such as HIV/AIDS and other sexually transmitted infections, influenza, tuberculosis, malaria and illness from potential agents of bioterrorism. NIAID also supports research on transplantation and immune-related illnesses, including autoimmune disorders, asthma and allergies.

Linda Joy | EurekAlert!
Further information:
http://www.niaid.nih.gov

More articles from Health and Medicine:

nachricht Laser activated gold pyramids could deliver drugs, DNA into cells without harm
24.03.2017 | Harvard John A. Paulson School of Engineering and Applied Sciences

nachricht What does congenital Zika syndrome look like?
24.03.2017 | University of California - San Diego

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Argon is not the 'dope' for metallic hydrogen

24.03.2017 | Materials Sciences

Astronomers find unexpected, dust-obscured star formation in distant galaxy

24.03.2017 | Physics and Astronomy

Gravitational wave kicks monster black hole out of galactic core

24.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>