The researchers determined that their work with HIV could correlate with finding a universal antivenin.
Scientists with Scripps Research in La Jolla, CA have developed an antibody that they claim blocks the effects of snake venoms from snakes found in Africa, Asia and Australia. The scientists say the antibody has protected mice from the usually deadly effects of venomous snakes, including the black mamba (Dendroaspis polylepis) and the king cobra (Ophiophagus hannah). They describe their findings in the February 21, 2024 issue of Science Translational Medicine.
To achieve this, the researchers used man made laboratory toxins to “screen billions of human antibodies and identify one that can block the toxins’ activity.” They say that the screening and identifying the antibodies is a big stem toward a universal antivenin that can be used and deployed to treat venomous snake bites from all venomous snake species.
“This antibody works against one of the major toxins found across numerous snake species that contribute to tens of thousands of deaths every year,” senior author Joseph Jardine, PhD, assistant professor of immunology and microbiology at Scripps Research said in a press release but out by the research center. “This could be incredibly valuable for people in low- and middle-income countries that have the largest burden of deaths and injuries from snakebites.”
Jardine previously worked with a team of researchers studying how “broadly neutralizing against the human immunodeficiency virus can work by targeting areas of the virus that cannot mutate.” The researchers determined that their work with HIV could correlate with finding a universal antivenin. The found that snake venoms also have regions within the toxin that cannot mutate, like HIV and an antibody that is targeted to attack that area that cannot mutate might just work against “all variants of that toxin.”
New Human Antibody May Result In Universal Antivenin For Venomous Snake Bites
The researchers were able to isolate and compare venom proteins of snakes of the Elapidae family, including mambas, cobras and kraits. Their research found that a single protein called three-finger toxins (3FTx) is present among all venomous elapid snakes and this protein contained small sections that appeared similar among all the different species that they studied. This single protein is responsible for whole body paralysis, which the researchers say makes it an ideal target within the venoms.
The researchers then examined about 3,800 antibodies and narrowed it down to 30 antibodies. They determined that the antibody called 95Mat5 had the strongest interactions among the toxin variants. They found that this antibody was effective in blocking the 3FTx protein from the many-banded krait and other venomous elapids.
The researchers then tested the 95MAT5 antibody on mice that were injected with venoms of the many banded krait (Bungarus multicinctus), the Indian spitting cobra (Naja kaouthia), black mamba and king cobra. The researchers found that not only were the mice protected from paralysis, they also didn’t die from the toxin injections.
This is where their study of HIV came in, as the 95MAT5 antibody was very effective at blocking the 3FTx variants, as they mimicked the structure of a human protein, in the same fashion as the broad acting HIV antibodies mimicked a human protein.
“It’s incredible that for two completely different problems, the human immune system has converged on a very similar solution,” Jardine said. “It also was exciting to see that we could make an effective antibody entirely synthetically—we did not immunize any animals nor did we use any snakes.”
The researchers also determined that the 95Mat5 antibody was effective against all elapid venoms, it didn’t work on snakes of the Viperidae family. So Jardine and his colleagues are working on an antibody that works against viper toxins. If they are able to find the right antibodies, they believe that combining the antibodies with the 95Mat5 could lead to a universal antivenin for most, if not all snake venoms.
The complete study, “Synthetic development of a broadly neutralizing antibody against snake venom long-chain α-neurotoxins” can be read on the Science Translational Medicine website.