What are the immunogenic agents?

Immunogenic agents are substances that are capable of stimulating an immune response in the body. This can include the production of antibodies and/or the activation of immune cells. Some common examples of immunogenic agents include:

* Vaccines: Vaccines are preparations that contain antigens, which are molecules that are recognized by the immune system as foreign. When a vaccine is introduced into the body, the immune system produces antibodies against the antigen, which can help to protect against future infection with the same pathogen.

* Toxins: Toxins are poisonous substances that are produced by bacteria and other microorganisms. When a toxin enters the body, it can cause tissue damage and illness. However, toxins can also be immunogenic, and exposure to a toxin can lead to the production of antibodies that can protect against future infection with the same microorganism.

* Allergens: Allergens are substances that can cause an allergic reaction. When an allergen is encountered, the immune system overreacts and produces antibodies called IgE, which bind to mast cells and basophils. When an allergen is encountered again, it binds to the IgE antibodies on these cells, causing them to release histamine and other inflammatory mediators, which can lead to symptoms such as sneezing, runny nose, watery eyes, and difficulty breathing.

* Transplant antigens: Transplant antigens are proteins that are expressed on the surface of cells. When an organ or tissue is transplanted from one person to another, the recipient's immune system can recognize the donor's transplant antigens as foreign and attack the transplanted organ or tissue. This can lead to a condition called transplant rejection.

Immunogenic agents are an important part of the body's immune response. By stimulating the immune system to produce antibodies and other immune cells, immunogenic agents can help to protect against infection and disease.