o The Frog Blog: Biology Prize Entries 2011 - Allergens

Friday, 25 March 2011

Biology Prize Entries 2011 - Allergens


Substances called allergens cause allergies. An allergy is a form of hypersensitivity, the most severe of its kind. It involves the activation of extreme amounts of certain white blood cells, known as mast cells and basophils. These are sent by a certain antibody known as IeG which leads to an intense inflammatory response to combat these allergens. Allergies can be found through skin responses, but also through blood tests, where samples are taken to detect any excessive presence of the antibody IeG.

Allergies are becoming far more common amongst humans and are rising at an alarming rate, making those of our generations to come even more susceptible to symptoms caused commonly by peanuts or washing powder.

We know this as these problems didn’t occur one hundred years ago, nor were they any sort of medical threat compared to now. Just 10% of the western population in 1980 were said to suffer of allergic reactions, yet today, there has been a considerable rise and now over three times the amount in 1980 experiencing allergies. According to the Global Allergy and Asthma Network, over half of the worlds population will experience an allergy by 2015. But what is causing this rise? Surely with the rise of technology these insignificant hypersensitive disorders of the immune system should seem meaningless. But it’s clearly not the case.

Studies have shown that those who live on farms are less prone to developing allergies than those that love in urban areas. Dr Erika Von Mutius, who carried out these studies said, “The farm studies show that there must be some combination of factors, some probably microbial-whether from animal faeces, grass dust, or unpasteurised milk-that guard against immune regulation problems.

It was also said that microbes could also be found in a vast area in the intestinal wall. Studies were carried out taking Estonian babies and comparing them to those of Sweden. Sweden , which is known for its high allergy rates, showed that the babies had a lot less diversity of microbes in its intestine. This thus may show us that our immune system is altered by the diversity of our exposure.

Scientists are blaming our lack of exposure to everyday bacteria, and how it is deterring our immune’s systems efforts to control itself, as a reason for the higher incidents of allergies in this generation. Some also blame the rise of hygiene through the “hygiene hypothesis.”

This theory states the reasons for the rising in those suffering is due to the lower incidences of infection in childhood, or in other words, the over cleanliness in ones childhood. It is said that because of this change in lifestyle we are not being exposed to microbial or other species, therefore allowing us to not develop our immune regulating defenses. David P Strachan who was the first to look into it scientifically showed that those in larger families who were more susceptible to infectious agents from their siblings, were less likely to have hay fever or eczema than only-children.

These allergens are harmless to most, but in some bodies, some substances cause immunological responses, such as the arrival of TH2, or T-Helper 2 cells. Normally bacteria and Viruses provoke the TH1 response, which is seen as less severe. The “Hygiene Hypothesis” claims that the insufficient use of TH1 has caused an over activated TH2 responses which then leads to an allergic reaction.

Aoise Keogan Nooshabadi, Form V

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