Thursday, December 29, 2016
Antivenom made from nanoparticles could eventually treat bites from any snake.
Different types of snakes produce different types of toxins which means snake bite victims not only need to get a dose of antivenom as soon as possible, but they have to get the right one. Now, researchers report that they have devised nanoparticles that sop up a variety of common venom toxins in test tube studies, a key stride in coming up with the first ever broad-spectrum snake antivenom. The strategy could eventually be used to combat toxins from scorpions, spiders, bees, and other venomous creatures.The lack of such a therapeutic is part of the reason that more than 100,000 people a year die from snake bites, mostly in Africa and Southeast Asia. That’s not the only danger, venomous snakes bite an estimated 4.5 million people every year, nearly 3 million of whom suffer serious injuries, such as the loss of a limb. This is because almost all snake bites occur in rural areas where people lack ready access to a clinic stocked with antivenom and in many cases, victims receive the incorrect antivenom. Producing conventional antivenom isn’t easy. The process starts by injecting an animal, often a horse, with a small amount of diluted venom from a particular snake. The animal’s immune system produces a mixture of antibodies capable of binding to and inactivating the toxins. Blood is then extracted from the animal, and the antibodies are purified and formulated for injecting into bite victims. Conventional antivenoms have several problems, as producing antibody-based antivenoms is time consuming and expensive, making it difficult for drug companies to make money on their sale, says Ken Shea, a chemist at the University of California, Irvine, who led the new work. That has contributed to a recent worldwide shortage. The antibody formulations must also be refrigerated, making them less accessible in the poorest parts of the developing world where they are often needed most.continue