In this video, we're going to briefly discuss how adaptive immunity can also sometimes cause unintentional damage to the host. In addition to innate immune responses such as inflammation, adaptive immune responses can sometimes also lead to accidental damage to the host. For example, antibody-antigen complexes, which are complexes consisting of an antibody binding to its specific antigen, can form during an immune response. Sometimes, these antibody-antigen complexes may not be detected or eliminated by phagocytes and can build up or collect in specific types of organs, such as the kidneys or specific types of joints. When these antibody-antigen complexes accumulate in specific organs, they can lead to unintentional damage. They can damage capillaries in the kidneys called glomeruli, resulting in kidney failure, where the kidney no longer functions the way it should.
In addition to antibody-antigen complexes leading to unintentional damage, certain types of infections also result in the production of antibodies that bind to surface proteins of self cells. This is when antibodies bind to our own self cells, causing autoimmune diseases where our adaptive immune system starts to target our own healthy self cells.
Below, we're showing you an example of how adaptive immunity can also cause unintentional damage to the host. Notice over here, we're showing you our kidneys. This is a cartoon image of our kidneys. Notice that the cartoon image of our kidney is saying, "Stay away from me; you are hurting me," addressing the antibody-antigen complex. This is the antibody-antigen complex. Notice that the antibody is this Y-shaped protein here, and the antigens are these little blue molecules at the tip. These can sometimes build up and cause damage. Over here on the right-hand side, we're showing you the kidney, highlighting these antigen-antibody complexes building up in the kidney tissues. The buildup of these complexes can sometimes settle in the kidneys and again cause kidney damage, leading to kidney failure. This is just a brief lesson talking about how, in some cases, the adaptive immune system can cause unintentional accidental damage to the host. We'll be able to get some practice applying these concepts and learn more as we move forward. So, I'll see you all in our next video.
