Andrea Graham, an evolutionary biologist, and her colleagues at Princeton University, have found that people with high levels of “self-reactive” antibodies (implicated in autoimmune diseases’ development) were less likely to have a type of chronic viral infection and were more likely to live longer.
Some scientists believe that these self-reactive antibodies might clear dying cells and other debris from the body, and even play a role in watching for cancer cells.
It seems that evolution produced autoimmunity to bring advantages to humans (Aaron Blackwell, an evolutionary anthropologist at the University of California, Santa Barbara, concurs); unfortunately, as T1D and other autoimmune disease sufferers know, evolution sometimes misfires. It really might be a case of ‘too much of a good thing’.
Source: New Scientist 29 July 2016
Type 1 Diabetes: Looking For a Cure 