Assertion: rheumatoid arthritis's system | /r/CapableOf | start attacking joint
Facets:
Source sentences:
text: At this point, scientists don’t know what makes the immune system start attacking healthy cells, tissues, and joints.
text: Rheumatoid arthritis can affect people of any age including very young children and it is a condition where the immune system which usually protects us from infections, starts to attack the joints causing pain, stiffness and swelling.