A human antibody prevents disease in monkeys infected with the deadly Hendra virus. The virus, first identified in 1994, normally sickens horses, but also kills about 60% of humans who become infected.

Christopher Broder at the Uniformed Services University in Bethesda, Maryland, and his colleagues show that a human monoclonal antibody, m102.4, blocks the disease in African green monkeys. These animals provide a model in which the blood-vessel-destroying infection mirrors that in humans. The researchers infected 14 monkeys with lethal doses of the virus. They then infused 12 of the animals with two doses of the antibody, which binds to a viral protein used by the virus to attach to host cells. Monkeys injected 10 and 24 hours after infection remained disease-free; those injected after 72 hours exhibited neurological symptoms, but recovered. The two control monkeys died. The team next plans to test this antibody against the closely related, and even more deadly, Nipah virus.

Sci. Transl. Med. 3, 105ra103 (2011)