 -criteria: Healthy controls, recruited in part via the NIH Normal Volunteers program, and age- within 5 years, gender- and race-matched when feasible to a subset of probands as controls needed for specific studies. Normal volunteers should be in good health, without a recognized systemic rheumatic disorder or other autoimmune disease, and should not be taking anti-inflammatory medicines, including nonsteroidal anti-inflammatory drugs NSAIDs or corticosteroids. 