Tuesday, October 12, 2010
Food Allergies turned off in Mice
This is a promising result for food allergy management. Perhaps we will see such allergies off.
Most folks have only hearsay exposure to the serious problem of food allergies. It is just uncommon enough that few come across it and most sufferers actually never talk about it at all.
The result is that a collapse and suffocation will not be understood immediately too often as even dangerous as observers go into shock. And who carries an epi-pen in their pocket with the life saving adrenaline shot.
Thus any protocol that can further minimize that risk is welcome.
Today, I have just seen the first report telling folks that in the event of a heart attack (or suffocating allergic reaction) the best practice is to press on the heart and not waste any effort of assisted breathing. I knew this myself from personal experience, having survived twenty minutes without a natural breath but receiving CPR.
The bloodstream has a good supply of oxygen so long as there is some motion as that provided by squeezing the heart. It is sufficient to allow emergency vehicles to arrive in most urban environments.
Obviously an allergy sufferer lapsing into unconsciousness needs blood sloshing to survive. Heart compression will do this.
Researchers discover way to turn off severe allergic reaction to food in mice
By Darren Quick
22:58 October 3, 2010
There is no known cure for food allergies with sufferers forced to constantly check the ingredients on food packaging and make enquiries at restaurants before digging into a meal. Even taking such precautions it is almost impossible to avoid all food allergen exposure, especially with children. With even minor exposure having the potential to cause severe or even life threatening reactions in some people, the discovery of a way to turn off the immune system’s allergic reaction to certain proteins in mice, could have implications for the millions of food allergy sufferers worldwide.
Allergic reactions to food occur when the immune system misidentifies an otherwise innocuous food protein as harmful, and then attacks the protein with a ferocity far greater than required. Last year we reported that a team at
discovered it was possible for some people allergic to peanuts to build up a tolerance by slowly giving them higher and higher doses of peanut flour in their food each day. While promising, for this method to remain effective the subjects had to keep a daily dose of peanuts in their diets to maintain the tolerance. Duke University
Now a research team at Johns Hopkins University has discovered that one kind of immune cell in the gastrointestinal tract called lamina propria dendritic cells (LPDC), which are considered the first line of defense for a body’s immune system, expresses a special receptor, SIGNR1, which appears on the cells’ surface and binds to specific sugars.
Test results on mice
In the laboratory, the research team, led by Shau-Ku Huang, Ph.D., a professor of medicine, and Yufeng Zhou, M.D., Ph.D., a postdoctoral fellow in the Division of Allergy and Clinical Immunology at Johns Hopkins University School of Medicine, took a food protein that causes allergies in mice and modified it by adding special sugars.
They hypothesized that, when ingested by the mice, the modified proteins would be able to bind to what are known as the SIGNR1 receptors on the immune system cells. Bound in this way, the immune system would learn to tolerate the modified food protein – and the protein would no longer induce an allergic reaction, even when consumed in its unmodified form.
The mice were fed the modified protein once a day for three days. Five days later, they were fed the protein in its unmodified form. Another group of mice was not fed the modified protein at all. The severity of the allergic response to the unmodified protein – which in the control-group mice tended to be tremors, convulsions and/or death – was significantly decreased in those mice that had been pre-fed the modified protein.
Some still had minor reactions like itchiness or puffiness around the eyes and snout, but none had serious ones. These mice appeared to be desensitized to the food protein, even when it was fed to them in its unmodified form, says Zhou. In this model, SIGNR1 plays a key role in shutting off some responses in the immune cells, but the researchers don’t yet know whether this is the only function of this receptor.
, it is estimated that six to eight percent of children under the age of three and nearly four percent of adults have food allergies. And the prevalence of allergies is rising, particularly in the developed world, with children growing up in too sterile an environment thought to be a major contributing factor. U.S.
Whatever the reason, if the Johns Hopkins team can confirm that their process in mice can also occur in humans it will provide hope that the body could be trained to tolerate food allergies that lead to roughly 300,000 emergency room visits and 100 to 200 deaths each year in the U.S. alone – and it could also mean that one day I might be able to try a peanut butter sandwich and see what all the fuss is about.
The research team's findings are published online in the journal Nature Medicine.