As spring emerges with its promise of sunshine, lush greenery, and vibrant blossoms, most of us eagerly embrace the season’s beauty and warmth. Yet, for a portion of the population, springtime arrives with a different companion – a pesky, often debilitating foe known as allergies.
These immune system overreactions can manifest as incessant sneezing, watery eyes, and, in more severe cases, even breathing difficulties. Allergies are a perplexing phenomenon because their triggers are as diverse as the world is vast. Everything from grass and flowers to ragweed, peanuts, bee stings, penicillin, soy, and latex, among countless others, can incite these hypersensitive reactions. Astonishingly, an estimated 40 percent of the global population grapples with allergies, and this figure continues to climb. But how can something as innocent as a tiny, delicious peanut pose a deadly threat to some? This enigma beckons us to explore the intricate world of allergies. To delve into the realm of allergies, it’s essential to start with the immune system – your body’s guardian of health. This intricate system, designed to protect you, can sometimes act like an overzealous soldier in individuals with allergies. The culprits behind this immune system misfire are lymphocytes, the white blood cells that function as diligent hall monitors patrolling your body in search of antigens—foreign invaders like parasites, bacteria, and viruses.
When a lymphocyte encounters an antigen, it springs into action, producing Y-shaped proteins known as antibodies. Humans boast an astonishing arsenal of nearly ten billion different antibody types, each tailored to bind to a specific antigen, effectively neutralizing the perceived threat. It’s akin to having the keys to ten billion distinct locks, ensuring the body’s defense is robust and versatile.
However, in those with allergies, the immune system’s lymphocytes often become perplexed. They categorize harmless substances, allergens, as dangerous antigens. Allergens themselves are essentially antigenic proteins, sometimes functioning as enzymes. This confusion in the immune system’s response leads to the characteristic symptoms and discomfort experienced by individuals with allergies.
Scientists remain baffled about what makes certain proteins trigger such strong reactions in some individuals’ immune systems. These proteins don’t resemble the usual culprits like viruses or bacteria, yet the immune system treats them as potential threats.
However, doctors have identified that although numerous substances can cause allergies, some are more likely to provoke an immune system overreaction. This explains why just eight common foods, namely tree nuts, eggs, soy, peanuts, fish, shellfish, milk, and wheat, account for a staggering 90% of all food allergies. When someone encounters an allergen for the first time, their immune system’s lymphocytes go into action, producing a batch of antibodies. These antibodies are like special keys that the immune system creates to defend against the specific allergen it perceives as a threat. These antibodies are called immunoglobulin E or ‘IgE’.
Everyone possesses IgEs, and these antibodies have a specific job. When they attach to certain immune cells, these cells release enzymes that aid in fighting off infections. This defense system evolved to protect us from parasitic worms and bacteria, and it’s typically quite effective—unless something goes awry.
In individuals with allergies, when their lymphocytes encounter an allergen, their immune cells go into frenzy and start overproducing these enzymes. This overproduction is what leads to the symptoms of an allergic reaction, like a runny nose, itching, or localized skin swelling known as hives. In more severe cases, allergic reactions can involve symptoms such as nausea, vomiting, or difficulty breathing.
The severity of these reactions depends on various factors, including the amount of allergen in the body, the concentration of immune cells with IgEs attached to them, and the quantity of enzymes being produced. For some individuals, the problematic enzyme can be histamine.
Histamine serves a vital role in our bodies by dilating blood vessels and increasing mucus production. This response allows infection-fighting cells to travel to areas that need their assistance. However, an excess of histamine can lead to uncomfortable symptoms like itching or a runny nose. In contrast, some individuals may experience a heightened release of an enzyme called tryptase, which is associated with the most severe allergic reaction possible – anaphylactic shock. An excessive surge of histamine and tryptase can lead to a dangerous drop in blood pressure. Furthermore, it can cause the bronchial tubes to constrict, making breathing increasingly difficult, and in some cases, the throat may swell, completely cutting off the oxygen supply. Tragically, hundreds of people in the US lose their lives each year due to anaphylactic shock. This is why individuals with severe allergies often carry an epinephrine shot, as it can be a life-saving measure in such emergencies.
Epinephrine is a form of adrenaline. When injected, it constricts the blood vessels and eases swelling, allowing the sufferer to hopefully breathe again. The effects although lasts for some minutes so the person has to see a doctor.
So that’s how allergies work and these are their symptoms.
