'Knockout' technique tested successfully on mice

Allergies, like the common cold and asthma, have basically defied the best efforts of modern medicine to cure them. Now, a doctoral candidate at the Hebrew University of Jerusalem School of Pharmacy has come up with a new approach that offers hope for getting rid of them.

For his efforts, Chilean-born Ido Bachelet, a first cousin of the president of Chile, Michelle Bachelet, and a Ph.D. student under the supervision of Prof. Francesca Levi-Schaffer, has been named the winner of one of this year’s Barenholz Prizes for Creativity and Originality in Applied Research. The award, named for its donor, Yehezkel Barenholz, the Dr. Daniel Gof Cancer Re. Miller Professor search at the Hebrew University-Hadassah Medical School, was presented recently during the Hebrew University Board of Governors 70th meeting.

Bachelet’s research has focused on mechanisms that regulate the function of mast cells – the “villains” in triggering allergic reactions. When exposed to allergens, mast cells react violently and release an enormous array of pro-inflammatory substances, of which histamine is a well known example. These substances lead to acute symptoms ranging from stuffy nose, rash, and airway constriction to the lethal shock known from food or venom allergies. Later on, they attract inflammatory cells that will maintain the response, which often persists as a chronic disease.

Although allergies are usually not perceived as lethal, reality is different. In 2005, over 250,000 people died from asthma worldwide. The World Health Organization estimates that this rate will increase by 20 percent within the next decade if urgent action is not taken. Asthma is the most common chronic disease among children.

Bachelet has identified a receptor protein on mast cells, termed CD300a. This receptor has a prominent negative effect on mast cell activity, virtually shutting down the cell from unleashing allergic responses. Unfortunately, CD300a is widely found throughout the immune system, and simply targeting it could result in undesired, overall immune suppression with serious consequences, as can happen with steroids.

In order to overcome this problem, Bachelet and his research colleague, Ariel Munitz, have designed a small, synthetic, antibody fragment that has the unusual ability of recognizing two targets simultaneously -- the receptor CD300a and a mast cell-specific marker. Thus, the antibody targets CD300a only on the surface of mast cells, avoiding suppression of other immune cells. This antibody potently eliminated four different types of allergic diseases in mice. Moreover, when mice suffering from severe chronic asthma received the antibody in nose drops, they completely reverted to normal, healthy mice in less than two months.

This pioneering project, termed RECEPTRA, presents a novel therapeutic strategy for acute and chronic allergic diseases, and is currently being licensed through Yissum, the Hebrew University’s technology transfer company, to pharmaceutical companies for further development and eventual clinical trials.

Based on its enormous potential, Bachelet and his team predict that with further development, their technology will become the first line of allergy therapy in the near future.

Source: The Hebrew University of Jerusalem

Related stories:

Using novel tool, researchers dig through cell 'trash' and find treasure
A person's trash can reveal valuable information, as detectives, historians and identity thieves well know. Likewise, a cell's "trash" may yield certain treasures, University of Delaware researchers have found.
Multi-tasking molecule holds key to allergic reactions
As the summer approaches most of us rejoice, reach for the sunscreen and head outdoors. But an ever-growing number of people reach for tissue instead as pollen leaves eyes watering, noses running and spirits dwindling. Hay fever is just one of a host of hypersensitivity allergic diseases that cause suffering worldwide and others, such as severe reactions to bee stings or eating peanuts, can be more serious and even fatal.
Scientists discover how an injured embryo can regenerate itself
Keep its organs in relative proportion
More than 80 years have passed since the German scientist Hans Spemann conducted his famous experiment that laid the foundations for the field of embryonic development. After dividing a salamander embryo in half, Spemann noticed that one half – specifically, the half that gives rise to the salamander's 'belly' (ventral) starts to wither away. However, the other 'back' (dorsal) half that develops into its head, brain and spinal cord, continues to grow, regenerating the missing belly half and develops into a complete, though be it smaller, fully functional embryo. Spemann then conducted another experiment, where this time, he removed a few cells from the back half of one embryo and transplanted them into the belly half of a different embryo. To his surprise, this gave rise to a Siamese twin embryo where an extra head was generated from the transplanted cells. Moreover, although the resulting embryo was smaller than normal, all its tissues and organs developed in the right proportions irrespective of its size, and functioned properly. For this work, Spemann received the Nobel Prize in Physiology or Medicine in 1935.
New research on octopuses sheds light on memory
Research on octopuses has shed new light on how our brains store and recall memory, says Dr. Benny Hochner of the Department of Neurobiology at the Alexander Silberman Institute of Life Sciences at the Hebrew University of Jerusalem. Why octopuses?
Test of bacteria toxin delivery system could pave way for new antibiotic drugs
Researchers at the Hebrew University of Jerusalem have achieved a breakthrough in monitoring the toxin-delivery system of highly pathogenic bacteria – an accomplishment that could help pave the way for new drugs that will be capable of neutralizing those germs.
Overcoming Drug Resistance—Nanoparticles Trigger Built-In Cell-Death Signal
One of the most vexing problems in treating cancer is the propensity of tumors to develop resistance to a wide range of anticancer drugs. Over 70 percent of ovarian cancer patients, for example, have drug-resistant tumors at the time of their initial diagnosis, and virtually all patients who relapse have drug-resistant tumors.
Synthetic molecules hold promise for new family of anti-cancer drugs
Synthetic molecules designed by two Hebrew University of Jerusalem researchers have succeeded in reducing and even eliminating the growth of human malignant tissues in mice, while having no toxic effects on normal tissue.
Finding out what the Big Bang and ink jets have in common
It often turns out there is more to commonplace everyday events than meets the eye. The folding of paper, or fall of water droplets from a tap, are two such events, both of which involve the creation of singularities requiring sophisticated mathematical techniques to describe, analyse and predict. On the positive side, there is much in common between many such singular events across the whole range of scales, from microscopic interactions to the very formation of the universe itself during the Big Bang.

News discussion:

Medicine & Health news