SearchWhat is RA?RA TreatmentLiving with RAFind a RheumatologistRA ResourcesGet a Joint ProfileWhat is RA?Understandingthe ImmuneSystemThe Role ofInflammationRA: The Body in TurmoilThe HealthyJointThe RA Joint vs.The Healthy JointRA Joint SymptomsGet aJoint Profile— FreeWhat is RA?0%AudioE-mail a FriendTranscript903288-916013Click to StartWhat is RA?RA (rheumatoid arthritis) is an autoimmunedisease, which means the body is attackingits own healthy cells and tissuesRA causes pain, swelling, stiffness, and loss of functionin the joints. Over time, the inflammation of RA can causedamage to the joints.An estimated 1.3 million Americans have RARA is 2.5x more common in womenRA often begins between the ages of 30 and 50RA is associated with a high disability rateRA is a life-long autoimmune disease that progresses over time and couldpotentially affect other parts of the bodyNo one knows exactly what causes some people, but not others, to develop RAUnderstanding theImmune SystemThe immune system is a complex networkof cells and cell components that interactwith each other to defend the bodyagainst infectionsCirculating white blood cells, "leukocytes," patrol for foreign invaders such as bacteria or virusesWhen white blood cells encounter suchinvaders, they trigger an immune responsethat results in their destruction and removalAny "foreign" or "non-self" cells areconsidered dangerous to the bodyInflammation can occur when white bloodcells release cytokines.The Role of InflammationInflammation is the body's normalresponse to foreign invaders, such asbacteria and virusesAs part of the immune response, white blood cells releasemolecules, "cytokines," into the bloodstreamSome of these cytokines act as messengers of theimmune system, specifically to promote inflammationInflammation helps the body contain the infectionso it does not spreadThe inflammatory response is self-regulated; once theforeign invader is removed, healing begins and theinflammation goes awayRedness, swelling, andpain are hallmarks ofinflammationHealthy cells and tissue are attacked as though theywere potentially harmfulWhen the body attacks itself, the "foreign" substancecan never be removed , so it sets off the sameinflammatory response — over and over againRA is an autoimmune disease, in which cells and tissuesof the body are  affected, primarily, those in the jointsTemporary inflammation means the immune system is doing its job — but long-term inflammation can be harmfulIn RA, cytokinesare released overand over again.RA:The Body in TurmoilIn automimmune diseases, the immunesystem mistakes some normal partof the body as "foreign"The Healthy JointThe synovium is crucial to the healthof the joint and is often the first area targeted by RAJoint capsuleencloses the joint to protect andsupport it.Synovial Fluidlubricates and nourishes the cartilageand bones inside the joint capsule.Synoviumis the thin layer of tissue liningthe joint capsule.Cartilagehelps reduce the bone fri