PATHOLOGY

Detailed explanation-1: -Antigens are substances (usually proteins) on the surface of cells, viruses, fungi, or bacteria. Nonliving substances such as toxins, chemicals, drugs, and foreign particles (such as a splinter) can also be antigens. The immune system recognizes and destroys, or tries to destroy, substances that contain antigens.

Detailed explanation-2: -When an antigen enters your body, the B-cells of your immune system inspect it. B-cells have special parts (receptors) that test the antigen to see if they fit together, like a lock and key. If it’s a fit, the B-cell makes chemicals called antibodies that all have the same shape to recognize the antigen.

Detailed explanation-3: -(AN-tih-jen) Any substance that causes the body to make an immune response against that substance. Antigens include toxins, chemicals, bacteria, viruses, or other substances that come from outside the body. Body tissues and cells, including cancer cells, also have antigens on them that can cause an immune response.