Question

Single Antigen, Multiple Organs Some Type-II immunopathology mediated autoimmune diseases have manifestations in multiple different organs. Discuss how antibodies to one single antigen can cause damage in multiple sites throughout the body. Things you might discuss include, but are not limited to where the antigen could be expressed, how antibodies are made, how they bind antigen, where they circulate, the ratios of antigen to antibody, mechanisms of the immune system that result in cellular/tissue damage, or how immune system components can affect other organs. You might also comment on what makes one antigen an attractive target rather than another. Please do NOT comment on all the things listed above, they are just to get you thinking. If you are having trouble getting started, it might help to think about a specific disease which affects multiple organs... Good Luck!

Answer 1

Adaptive immune responses are triggered by activation of antigen-specific T cells that produce antibodies against foreign antigens such as, for example, harmful viruses. These immune responses are useful to eliminate dangerous molecules from the body. In a normal immune reaction, the antibodies produced by T-cells target antigen molecules in order to be subsequently absorbed by phagocytic macrophage cells.

Autoimmune diseases are triggered by the response of the adaptive immune system against self-antigen molecules. Since the immune system can not eliminate antigens from the own body, this immune reaction generates an excessive inflammatory response, and it may lead to the damage of tissues and organs.