Reagins

Reagins are specific antibodies that are formed in response to contact of the immune system with certain antigens. They play an important role in protecting the body from infections and other diseases, and are also involved in allergic reactions.

Reagins were discovered in 1904 by the German immunologist Karl Landsteiner. He noticed that when sensitized mice were injected with blood serum from sick people, the animals developed symptoms similar to those of allergies. Landsteiner suggested that the serum contained specific antibodies that caused these symptoms.

These antibodies were later found to be reagins. Reagins are proteins that bind to antigens on the surface of cells and form complexes that can cause allergic reactions.

There are several types of reagins, each with its own unique antigen-binding domain. For example, class E reagins are associated with pollen allergens and may cause bloom allergies. Class G reagins, on the other hand, are associated with bacterial antigens and can cause bacterial infection.

In addition, reagins may play an important role in the development of autoimmune diseases such as rheumatoid arthritis or systemic lupus erythematosus. In these cases, reagins can attack the body's own cells, causing damage and inflammation.

Overall, reagins are important components of the immune system and play a key role in protecting against infections and allergic reactions. However, their excess production can lead to the development of autoimmune diseases and allergies. Therefore, understanding the mechanisms of reagin formation and function is important for the development of new treatments for these diseases.