With the sun shining, the birds singing, the smell of green grass and the sound of eggs baking on the pavement, you can’t help but say, “Summer is finally here!” With the appearance of all these wonderful things come the annoyances of runny noses, itchy eyes and violent sneezing. For all those who fall victim to allergies this time of year, I feel your pain. As I was incapacitated due to such symptoms a few weeks ago, the nerd in me wanted to find out why my body refuses to let me enjoy the beautiful weather outside.
Allergies result from a hypersensitive immune system response to a certain substance. The immune system misidentifies the substance as being something more harmful than it is; therefore, when the immune system responds, it does so with greater intensity than required. The results of these responses can range from mild irritations to fatal reactions (which is ironic given the primary purpose of the immune system).
The B-lymphocytes (B-cells) and T-lymphocytes are responsible for your inability to walk outside in peace. These cells are present all over the body and act as security guards by checking the surface marker proteins (analogous to passports) of every cell in the vicinity. If they discover an invader, the B-cell will change into a plasma cell and produce antibodies to fight the invader. The type of antibody produced in these cases is called IgE. Although these IgEs are present in everyone, those with allergies have lymphocytes that are unable to distinguish between harmful and non-harmful substances. This is due to a mutation on the gene which codes for these cells. As a result, the mutated B-cells will create massive amounts of antibodies that will attach themselves to “alerting” cells, called mast cells and basophils, all the same. It is important to note that all mast cells and basophils contain large stores of histamine.
What you may not know is that your first exposure to the allergen will not cause an allergic response; instead, your second brush with the molecule will result in the sniffling and itching. This is because it takes up to 10 days to build up a sufficient number of mast cells and basophils that are primed with the IgEs. Only after this period will symptoms appear. Whether it is a protein present on hay fever particles or a protein present on venoms, the response events are the same. When the particle enters the body, the IgE antibodies on the basophils and mast cells will recognize the allergen. Next, the antibodies will bind to it while still being attached to the “alerting” cells, which “alerts” a special group of complement proteins that circulate in the bloodstream. The complement protein will bind to the site and alert the subsequent complement protein in the sequence. When the sequence of nine proteins responsible for allergic response is bound to the site, the cells within the site are destroyed. Since the only cells at the site are mast cells and basophils, large amounts of histamine get released. Now that histamine and other allergy mediators are released, the blood vessels dilate in the affected area and the surrounding cells fill with fluid. If the allergen is detected around the nasal cavity, the release of histamine will result in itching, sneezing, wheezing and inflammation in that area of the body.
What is not completely understood is the mechanism of cross reactivity, where allergy sufferers exhibit reactions when exposed to substances similar to the original irritant. For example, if you are allergic to honeybee venom, you may later become allergic to other types of bee venom. While allergies are still a result of genetic mutation, the best thing you could to treat allergies is to simply avoid it or, for those who simply can’t avoid going outside, take medication. All allergy medications contain generous amounts of antihistamines, along with ingredients targeted to treat particular symptoms. For example, Claritin uses loratadine, a second-generation antihistamine that specifically relieves nasal and eye discomfort. On the other hand, peanut allergy sufferers have to be treated with epinephrine to treat symptoms like dilating blood vessels and constricting airways.
With that being said, not only can you blame your parents for your suffering (with conviction), you can also be more thoughtful in selecting the best allergy medication to treat your particular ailment; this is especially important for those who have had bad reactions to previous medications. Now that you’re a whole lot smarter after reading this, find the best allergy medication for you, take it, and skip down the street in celebration of being able to breathe again!
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