Subtitles section Play video Print subtitles So springtime is upon us, and the weather is beautiful! Flowers are blooming and people are breaking out their shorts and t-shirts. But, if you’re like me, you’re miserable, and stuck at home with a runny-nosed and puffy eyes. But why do we have to suffer from the horrible allergies? “An allergy is actually a mistake that the immune system is making. Normally we’d make antibodies to fight germs, or recognize germs, but in this case the immune system has made a mistake, it’s making an antibody that recognizes harmless things such as pollens or animal dander.” Inside every allergy sufferer, there lies an immune system that mistakenly produces an antibody known as immunoglobin E. When these unfortunate people breathe in the pollen, the antibody triggers an allergic reaction. But we’re not just talking about any kind of pollen, here. It’s commonly thought that allergy-causing pollen comes from big, pretty flowers like this, (Big Yellow sunflower image onscreen). But actually, that pollen is too heavy to go airborne. Allergies are cause by pollens from trees and grasses that are small and light enough to be carried by the wind. “When the immune system, somebody who’s allergic, recognizes these pollens, the immunoglobin E. activates cells of the immune system, mast cells, and these mast cells will release chemicals that cause allergic reactions. One of the most well-known chemicals that cause reactions is histamine. Histamine is a small organic molecule and how histamine works is as a small chemical messenger, finds a receptor that’s on many, many cells of the body called a histamine receptor and sends that cell a message. For example blood vessels when it binds to that receptor it tells the blood vessel to become leaky, which causes the runny nose that you get or for example they can cause receptors on nerves which the histamine will activate and that gives you the sensation of itchy nose that you might feel during pollen exposure.” So if you’re wheezing and sneezing this spring, try to stay indoors early in the morning when there’s more pollen floating around. But if you have to go out there, at least pack some tissues! And maybe some anti-histamines.