Arsenic can damage most of the body's major organs and the immune system.

BBC: By Helen Sewell of BBC Science

"For 80 percent of the common chemicals in everyday use in this country we know almost nothing about whether or not they can damage the brains of children, the immune system, the reproductive system, and the other developing organs, " said Dr. Phil Landrigan, a pediatrician and director of the Children's Environmental Health Center at Mount Sinai School of Medicine.

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Lupus is an autoimmune disease characterized by inflammation of the joints, skin, major organs and central nervous system as the immune system attacks healthy tissues and cells.

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Dr Wu and Mr Pearl realised that if they could stop the handshake happening, they would have a way of dampening the immune system's ability to detect transplanted organs.

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This would be useful in cases of severe injury where the immune system turns against the body and causes organs to shut down one by one.

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