Armored Personal Carrier. I think the APC is located where you find the Warden Crossbow.
Autoimmune diseases arise from an overactive immune response of the body against substances and tissues normally present in the body. In other words, the body actually attacks its own cells. An immune disorder is when the body cannot defend itself. [ Source: http://www.chacha ....n immune disorder is when the body cannot defend itself. [ Source: http://www.chacha.com/question/what-is-the-difference-between-immune-disorders-and-autoimmune-diseases ]. More Answers to  What is the difference between immune disorders and autoimmune diseases .
Lupus is an auto-immune disease that can last for decades. Auto-immune disease are disease where the immune system fights the body and organs rather than fighting viruses. With Lupus, the immune system over-reacts and begins to attack healthy tissue and organs - these attackes can be limited, or severe and can have many far-ranging effect.