The researchers inject a boron compound into an arthritic joint and expose the joint to neutrons. The boron captures some of the neutrons to form a radioactive substance that kills the inflamed synovium, represented by the gray spots. No one knows what initiates or how to cure rheumatoid arthritis, a potentially crippling disease that afflicts more than two million Americans. The disease arises when the immune system mistakenly targets the synovium, the membrane that surrounds a joint and holds in the lubricating synovial fluid. The synovium grows abnormally and invades cartilage and bone, causing them to soften and crumble.
Drugs can often hold the immune system in check.
But even after drug therapy, between 10 and 20 percent of patients continue to suffer in at least one joint. Then, the only way to slow the progress of the disease is to get rid of the synovium. Professor Yanch and colleagues are trying their technique on the knees of rabbits with induced rheumatoid arthritis. Early results are promising. But more work must be done before Professor Yanch can test the technique on people.