Some joints may be primed for rheumatoid arthritis before birth

Scientists have found evidence that vulnerability to rheumatoid arthritis may begin before birth. Finger joints commonly affected by the disease develop with different tissue structures and larger populations of specialized fibroblasts than joints that are usually spared. Those cells also respond differently to inflammation, suggesting that the architecture of each joint may help determine where arthritis eventually takes hold. The study, "The embryonic origins of site-specific arthritis," was published in Nature Immunology. It suggests that the answer may depend not only on the immune system, but also on biological differences built into individual joints during developmen... [5264 chars]