Allergic reactions

Synthetic molecule could stop acute allergic reactions

Scientists from the Stanford University School of Medicine and Switzerland’s University of Bern have recently made a discovery that should stop severe allergic reactions within seconds – the reaction by some and the consequent anaphylactic shock that results from exposure to allergens such as peanuts or bee venom.

To begin, here’s what happens in a typical acute allergic reaction.

The first time that a potential allergen enters the body, some people’s systems react by creating what are known as IgE (Immunoglobulin E) antibodies. These antibodies remain in the body even after the allergen has cleared out, where most of them proceed to link with Fc receptor molecules, which are found on the outer surface of mast cells.

When that same allergen is introduced to the body again, it binds with the antibodies clinging to the mast cells, causing those cells to release “inflammatory mediators” such as histamines – the result is a nasty allergic reaction.

What the scientists discovered was that an engineered protein-inhibiting molecule by the name of DARPin E2-79 is able to quickly strip the IgE antibodies from the Fc receptors. In p

actical terms, this means that “an interaction that normally lasts for hours or days in terms of its stability is stripped off in a matter of seconds,” according to Stanford’s Dr Ted Jardetzky, senior investigator on the study. In other words, it should stop an acute reaction in its tracks.

The team is now looking for molecules that do the same thing as E2-79, but that are smaller – this would make them better-suited to oral administration, plus they would be cheaper and easier to produce.

A paper on the research was recently published in the journal Nature.