how antigne is formed

Answer 1

An antigen is formed when a foreign substance enters the body. The immune system recognizes the substance as foreign and begins to produce antibodies, which are proteins that bind to the antigen and help the immune system to destroy it. As the immune system continues to be exposed to the same antigen over time, it becomes better at recognizing and fighting it, leading to the development of immunity. Antigens can include bacteria, viruses, fungi, and other substances that are not normally found in the body. Some antigens, such as those found on cancer cells, can also be produced by the body itself.