CLIFTON O. BINGHAM, MD: The patient has the right priming of their immune system and then the right set of outside forces come to play, this might be an infection that we haven't identified, it may be outside environmental triggers that we don't yet understand. But what happens is there's a confluence of these things that all come together at the wrong time for the particular patient that begin to activate the immune system.
ANNOUNCER: Immunological factors also play a role. A normal immune system protects the body from bacteria and viruses, while in rheumatoid arthritis, a misdirected immune response contributes to the disease.
ERIC RUDERMAN, MD: The best analogy would be to think about getting a cut on your skin. If you get a cut on your skin and it gets infected, it gets red, it gets swollen. And what’s happening there is your immune system is bringing all sorts of inflammatory types of cells into that area to help get rid of the infection. And when the infection is cleared, either on its own or with the help of an antibiotic, those cells tend to go away, and the swelling and the redness goes away, and it heals. In rheumatoid arthritis, it’s as if your joints are recruiting all these inflammatory cells from the body into the joint to fight off an infection that we can’t find, and it never goes away, and so it’s not as if it heals. The inflammation keeps going. It stays there. And that sets the whole cascade in motion that becomes rheumatoid arthritis.
ANNOUNCER: Proteins called cytokines drive the process.