If only Peter Parker had known. Scientists at the Universidade Federal de Minas Gerais in Brazil have engineered a protein with the properties of a potent anti-toxin from the venom of the Loxosceles intermedia, or reaper spider.
The protein can protect against the effects of a reaper spider’s bite, and because it’s made in a lab, it doesn’t require researchers to “milk” the spider itself or to generate venom antibodies using painful animal testing.
Loxosceles—also called recluse spiders or brown spiders—are found around the world but are most common in Brazil, where, according to the study authors, they cause nearly 7,000 human “accidents” every year.
A bite from a reaper spider causes the skin around the bite to die, leaving behind an open sore. Rarely, a bite can lead to severe bleeding, anemia, kidney failure, or death. The new protein itself is not toxic, but it offers protection from the effects of the spider’s venom, much like a vaccine.
"In Brazil we see thousands of cases of people being bitten by Loxosceles spiders, and the bites can have very serious side effects," study co-author Dr. Carlos Chávez-Olórtegui said in a press release. "Existing anti-venoms are made of the pure toxins and can be harmful to people who take them. We wanted to develop a new way of protecting people from the effects of these spider bites without having to suffer from side effects."
Saving Livestock (and Spiders) a World of Pain
Currently, clinical labs create anti-venom by first “milking” poison from a spider, snake, or insect and then injecting the venom into a horse, sheep, or goat, causing the animal’s body to produce antibodies to combat the toxin. The antibodies can then be harvested and given to a bite victim to slow or halt the effects of the venom.
"It's not easy taking venom from a spider, a snake or any other kind of venomous animal," Chávez-Olórtegui said. "With our new method, we would be able to engineer the proteins in the lab without having to isolate whole toxins from venom. This makes the whole process much safer."
Researchers must still inject the engineered protein into an animal to produce usable antibodies, but unlike with current methods, the animals don’t suffer the painful effects of the venom.
In the lab, rabbits given the new protein still created antibodies, and when they were injected with the venom itself, they were protected from skin damage and bleeding.
Chávez-Olórtegui and colleagues published their results this week in the journal Vaccine. The researchers believe their protein is an excellent candidate for the development of therapeutic serums or vaccines to protect against bites and stings from other poisonous animals, including snakes, scorpions, and jellyfish.