Answer:
The immune system attacks healthy cells.
Explanation:
Autoimmune diseases are conditions in which the immune system mistakes your own body for something foreign, for a threat. In these cases, the immune system releases proteins called autoantibodies that attack healthy cells. For example, when someone has lupus, their immune system can attack their skin, joints, blood, and kidneys. Some more autoimmune diseases are multiple sclerosis, inflammatory bowel disease, celiac disease, type 1 diabetes, etc.
