PATHOLOGY

Detailed explanation-1: -Antigens are any substances that the immune system can recognize and that can thus stimulate an immune response. If antigens are perceived as dangerous (for example, if they can cause disease), they can stimulate an immune response in the body.

Detailed explanation-2: -An antigen is a foreign substance that enters your body. This can include bacteria, viruses, fungi, allergens, venom and other various toxins. An antibody is a protein produced by your immune system to attack and fight off these antigens.

Detailed explanation-3: -In general, two main divisions of antigens are recognized: foreign antigens (or heteroantigens) and autoantigens (or self-antigens). Foreign antigens originate from outside the body.

Detailed explanation-4: -Non-self-antigens include the antigen structures found on the surfaces of foreign bacteria, viruses, fungi, parasites, or other non-native biocompounds. The immune system relies on antibody-antigen binding and the binding of antigens with receptors on B or T Cells to recognize non-self-antigens within the body.

Detailed explanation-5: -Innate immune recognition is mainly based on a series of germ-line encoded receptors that have been selected by evolution to recognize nonself molecules present in microorganisms. Innate immunity also recognizes changes in our cells caused by infection, such as the lack or induction of self molecules.