218. The Science Of Snake Venom

Show me the science with Professor Luke O'Neill. Hello, Luke O'Neill here and welcome to show me the science my weekly podcast when I pick a topic and we battle away. I love the old battering away of things and I've had an email from a guy called John asking for this one so John very happy to do it and John came across this paper it was about two weeks ago I guess three weeks ago now maybe and it's an immunology paper so thanks John for thinking of it because I'm an immunologist after all it's a fascinating paper came out in the journal sale and you can email me on L.A.O. Neill with two else at tcd.ie and if you have a topic more than be happy to cover it I feel I can so this one John recommended this it's a really interesting one and it is the science of snakes more accurately snake venom actually but amazingly what's triggered this is there may be a universal antivenom for snake bites so this is a study that was published to say it may be possible to have a universal treatment for snake bites and I remember if you get bitten by a snake the fangs go in and there are these venomous snakes and they squirt the poison into your system now this can kill you certain snakes are lethal but there are ways to mop up the venom mainly antibody based that explain that can save your life and they're very useful so it's an important area because guess what it's amazing how many people died there's 140,000 deaths a year from snake bites not on Ireland obviously because St. Patrick drove them all out apparently on a scientist must be writing because someone said that and there's 300,000 permanent injuries each year so even though snake bites might kill you the toxins in the venom will damage your tissues and that damage can be irreversible so it's quite a serious thing there's a need basically for better ways to treat people who have been envenomated as the word that used actually by a snake so and this study is really helpful for this now what was the basis for this study we'll get this there was a man and Frieda is his name got called Frieda right he was a man who kept snakes for a pet Tim Frieda just for his name he's a former truck mechanic from Wisconsin and his hobby was keeping snakes now we all have our hobbies wouldn't like him himself but hey whatever floats your boat and he self administered get this more than 850 doses of venom from snake into his own body and he might wonder why would you do that well it'll be clear in a minute so he managed to poison himself if you will with venom from cobras members rattlesnakes and a few other deadly species into his body and the reason he did it was he wanted to become immune to the snake bites because it's his hobby and he kept getting bitten by the snakes as well and it was causing discomfort so he wondered could he actually become immune to the venom that are in the snakes they was keeping as pets his second reason was any state of this he wanted to help scientists create a universal antivenom now this is an 18 year experiment we kept these pets snakes as a hobby and now we've known for a long time that you can raise antibodies to snake venom and example for example in horses and the antivenom that is used nowadays let's say a bitten by a cobra or whatever you can get an antivenom from the pharmacy or from wherever and it's normally horses that have been injected with the snake venom and the antibodies have been purified from the horse serum and that's what they inject into you and I remember antibodies latch onto proteins and mop them up and we use antibodies as therapies for many things actually and of course our immune system makes them some up viruses and bacteria and so on but in this case the antibodies are mopping up the snake venom and he did this because he knew his body would make antibodies to whatever venom he injected and that could then be used to revolutionize the treatment of snake bites for all of us basically and this experiment went over 18 years and a scientist called Jacob Klanable and he was the chief executive officer of a US biotech company called Sentivax now they aren't sponsoring this podcast that he's throughout but that was the company that was involved they heard of this and Jacob himself great quote from him I saw in one of the press releases it blew my mind I contacted him because I thought of anyone in the world as properly neutralizing antibodies it's him now they use the word neutralizing antibodies because of course these antibodies are binding the venom and neutralizing it you know making it less toxic as the way to think of it and but what they found in the animals a cocktail they could make well anyway one of them was Jacob went to see them all freed up got some blood and they were able to purify antibodies from his blood and indeed these are able to handle most of the venom that are in snakes that bite us and poison that's right and they made a cocktail also a small molecule venom inhibitor small little drug it could block some certain venom and some of them enzymes you can block them and this is the basis then for a universal antiven and the evidence is very strong they could use this stuff from freed as blood remember what I said earlier 850 doses of venom from all these different snakes so his blood was full of antibodies so a whole range of venom from different snakes they could take those antibodies out and now test them and they took mice as a model and they would inject the mice with different venom and long behold a drop of antibodies as aware from freed as blood could save the most his life so they proved in mice that these antibodies would work and remember it was already known for over a hundred years now actually that you could make antibodies and horses in sheep often from a single snake species and then that would then be used to neutralize a bite off that specific snake there's always been problems with this approach though because some antibodies purified from the sheep and the horses can cause an adverse reaction as kind of a laxis in other words you can develop almost like an allergy to the antivenom that's prepared from the blood of the sheep or the horse because they aren't human antibodies remember their antibodies made by the sheep or made by the horse and our own immune system reacts to them not in everybody there's small number of people but still it can be quite a serious side effect and then the other problem is what snake bit you because obviously each antivenom that was prepared in a horse or a snake was from you know injecting that horse or snake with one specific venom now what strikes me there is why weren't they putting loads of animals into horses and snakes I suppose because that would have killed our sheep and I would have killed them myself but the bottom line was you had to try to know what was the species of snake that bit you and in fact as Jacob himself said it's pretty tough that because you got to catch the snake the bit you bring it in with you in a plastic bag and say this was the snake give me some antivenom against that snake so much better if you had a universal antivenom for snakes and Frida is on record as well as saying he knew about the shortcomings and as a great statement he wanted to fortify himself against accidental bites from his collection of pet snakes so it's incredibly now of course it's not for the faint heart of this is it injecting yourself with snake venom and for all Tim he spent four days in a coma in 2001 after being bitten while milking in Egyptian cobra so now of course he thought himself I don't want to happen here again so he began injecting himself with low doses and he used 16 lethal snakes initially and he was offering his arm up actually but he didn't inject them I've just seen here now you got the snakes to bite him and then along the hole then he begins getting bitten both he didn't die and then finally he went on a YouTube channel actually and Jacob came across this and he got in touch and landed on a set of them waiting for this call sorry I've been waiting to find someone like this for a long time and he did now what was next then was in the testing the they took 19 of the WHA's category one and two deadliest species so snakes are categorized and how deadly they are the 19 different snake venom for chose and to test with the antibodies purified from Frida's blood and they were from Carl's snakes, members, cobras, typans and crates, spelt K or AITS and they isolated the antibodies and they got tested them and that allowed them to identify which antibodies would be best and so on and in the end they ended up with two antibodies that when combined with a anti sort of small molecule anti venom drug they got complete protection from 13 of the most deadly species of snakes that were that would be biting us and partial protection against many others they was not amazing so in the end the bottom line from all this was they could prepare antibodies from the blood of Frida and then combine them in various ways and basically protect us or protect mice anyway against many species of snake that would be injecting poisons into us and it's quite remarkable now most snake bites are caused by non venomous snakes and here's a bit of snake biology for you there were 3,700 species of snakes worldwide some people have a huge aversion to snakes I do we all do don't we I think we evolved not to like snakes because you know they can be so dangerous but only 15% so around about 325 species are the ones that you got to look out for overall so 15% of our snake species are potentially harmful if they bite us 61 genera and more lots of details on this is there's one genera called elapidate another called viperidate and 222 species in viperidate can actually cause us harm so we know a lot about the different type species species of snake and the ones that cause the most problems for us so around about 700 overall venomous species they reckon they can cause us harm and of course the most dangerous snake of them all the deadliest snake is the Taipan T-A-I-P-I-N that's found on Australia why are there so many horrible creatures found in Australia not horrible they're all beautiful but still you don't get bitten by a Taipan and dark tan color dark edge scales it is the most toxic venom of any snake and a single sample of the venom from the Taipan can kill a hundred human beings is that amazing very potent it targets nerve cells destroys them and then you get paralyzed and you can't breathe it also causes them massive bleeding because there's an anticoagulance that stops blood bleeding and multi organ failure because your body goes into shutdown basically so and there is an anti-venom available but in the case of Frida summer his blood was shown to protect against the Taipan in the mice he was able to raise antibodies against the Taipan's venom and that's extremely useful given how dangerous that particular snake is and now most snake bites happen in summer because snakes are active in their outdoors and they're all outdoors with them obviously tropical regions they live in tropical regions anyway agricultural areas as loads of snakes there as well so we know how to avoid them I suppose most victims are between the age of 17 and 27 and the ones who are most at risk of dying from a snake but at children because their bodies are smaller and the venom is more concentrated and causes more harm and older people because their hearts and so on and their their kidneys are a bit more fragile so therefore the snake venom can get in there and really damage those organs and then cause death so if you're older or over 60 or children there the ones to be mindful of because they're the ones who can be really harmed and the record show that they're the most at risk of dying now what was very interesting here was Frida getting back to our friend he was meticulous in his dosing schedule low doses he got in and made sure that the snakes were biting him low dose get the snake off and make sure it isn't too much and then he was cycling them different venom you know cyclic and exposure to different venom and then antibodies were getting made and he got boosting himself and then anybody who knows about vaccines will know you can't be boosting the immune response so very clever over the course of this period he was able to use different snakes and then it's low dose and then repeat you know and then he was able to get good protect antibodies in his system to protect them and it was viperous we're a key family of just noticed here as well now what's going to happen next with this well of course Jacob Glanville and his company think they way may well be able to make a universal treatment for snake bites and that's what's going to happen next because you can what you can do is you can make antibodies in a lab now and in fact there's many bio therapeutic antibodies used to treat arthritis for instance so this technology now to isolate the really powerful antibodies and then begin making them and then you make cocktails of them interestingly he also noticed that certain antibodies could block more than one venom that the similarities between these venom so different species might have a given venom the next species is a very similar one so that means you're getting cross protection against different species but ultimately the goal will be to have in pharmacies in places like Australia you go in after a snake bite and one shot of this universal anti-venom will work and protect you from being badly harmed by that snake venom and at the moment I'm testing them in dogs I know that's been bitten by snakes so dogs do get bitten by snakes especially in Australia and they end up in the vet and then they're going to die of the snake venom and they're trying these universal this universal anti-venom in dogs first and that's a really clever thing to do because it's a way to save the dog first of all and pet owners would appreciate that of course and then if it works and the dogs that's bound to work in the humans and they'll move into human trials and that is coming up pretty quickly I was reading that they're starting to try and dog's already and then they'll move onto humans and do a test in humans now of course humans is tricky because you've got people coming in I suppose and then you're going to have to give them this and then they might go and hang on a minute I might die of this snake when I'm not trying something experimental so let's see what happens in terms of the trials but certainly the future here a lot of excitement in the world of anti-venom because the future here could well be a single shot will protect you against severe harm and damage from a whole range of snakes and so therefore you don't need to go and hunt down the snake but bitch you to bring it in to pick which anti-venom it is it'll speed up the whole process and the prediction is of course it'll save lots of lives and as I mentioned already the striking numbers 140,000 people a year are dying of snake bites and that's usually because they don't have each anti-venom to deploy or they can access to an anti-venom so all those lives could be saved and then 300,000 permanent injuries could be prevented on the back of the universal anti-venom that was discovered in the blood of snake lover Tim Frieda so Tim if you're listening in and there isn't much of a chance could you be in Wisconsin but just in case you were I want to thank you because all of us all because you've managed to do something really important and good luck with the trials that are coming up now with the universal anti-snake venom that is the science of snake venom and thanks as ever for listening and of course my my podcast is a new soft production available for download every Thursday wherever you get your podcast