Plant-based vaccines for COVID-19 and other viruses | COVID-19 Special

Plant-based vaccines for COVID-19 and other viruses | COVID-19 Special

[Music] could plant-based vaccines save the world scientists say rice corn potatoes or lettuce can be used to produce antibodies it’s a kind of complex process which starts by the procedure that infects them with a foreign dna genetic material that reprograms them to stop doing everything else and just make one protein recombinant protein which is a medicine that we want to produce biotech firms are already in clinical trials with their plant-based drugs or awaiting approval from health agencies to combat ebola the norovirus and covet 19. i’m ben fazoulen this isn’t just about pleasing vegans a plant-based covert jab would be cheaper and quicker and instead of using hamster ovaries or monkey kidneys you can use veggies or even tobacco the plants being grown inside this greenhouse could form the basis of a new covid19 vaccine the nicotiana benthamiana to give it its proper name is currently the focus of a study by canadian biotechnology company medicargo and britain’s glaxosmithkline 20 000 people are taking part in the trial it’s the first time a plant-based vaccine is being developed you introduce the dna which triggers the production of a spike protein very similar to the coronavirus but which isn’t infectious when you remove it from the plant put it in the vaccine and add an adjuvant a substance that boosts the body’s immune response the vaccine can generate more antibodies preliminary results suggest the plant-based vaccine may produce up to 50 times more antibodies than other jabs gizelle clark is among 7 000 argentinian participants in the trial she works as a journalist and has written extensively about covid19 vaccines now she wants to learn more about production methods herself [Music] vegetarians and vegans are especially interested in the idea of a plant-based vaccine while no other covid19 jab is of animal origin either this particular trial has attracted many vegan and vegetarian test subjects in argentina the country with its rich livestock tradition is the second largest beef consumer per capita worldwide but the number of vegetarians and vegans is growing they now make up over 10 of the population linking meat consumption to environmental issues anything that bans animals from our plates is very controversial in argentina due to our traditions and deeply ingrained habits but every day people are becoming more environmentally aware against this backdrop a plant-based vaccine even one which is being tested on animals has already piqued the interest of many people [Music] i asked zachary leblanc from queensland university of technology why animals are still used to make vaccines hey ben well that’s uh it’s an interesting question um mainly when you say animals uh typically what’s used for vaccine manufacturers are actually animal cells so at that point i wouldn’t quite call it an animal because it’s not an organism at that point it’s just a cell in culture that’s being used to produce these vaccines which are complex proteins so i wouldn’t quite say that animals are being harmed in the process but the advantage of using plants is that it’s really in the scalability of the system versus these other mammalian cell based systems and why is it cheaper so it’s cheaper because of the scalability essentially um if you think about the inputs that you need for growing a plant right you need to put it you need to give it water you need to give it sunlight and you need to give it dirt you compare those inputs to a lot of these other systems which are fermenters that are used to culture large amounts of mammalian cells and it becomes it’s visibly a lot cheaper when you’re producing a plant to amplify this biomass which can then produce your vaccine i was also reading that there’s no need for bioreactors in some cases no purification process so i guess you’re cutting a lot of costs there and does that make it then safer all in all so um in in terms of safety yeah because if if you think about uh pathogens that act on mammalian cells if you’re producing um your vaccine mammalian cell it’s there is a possibility of a pathogen getting that can affect that mammalian cell also affecting the end user now if you’re using a plant um they don’t share a lot of they don’t share any pathogens with humans so you’re not going to have a pathogen that’s going to attack your your cultures that would then attack the end user so in that sense it’s more safe and to answer the bit about bioreactors actually um when you’re using plants as a production system the plant itself is the bioreactor so that that sort of feeds into why they’re more cost effective as a production platform so the million-dollar question for you zach how much quicker would we have immunized the world if we’d had a plant-based covert vaccine considering they’re quicker cheaper and safer yeah um i’d say it’s a yeah nearly a billion dollar crush question when you’re talking about covet vaccines but um uh i don’t think much would change to be honest um because the the hurdle is really getting through those clinical trials um and for production of a coded vaccine i mean there’s a group in north america called medicago that’s in phase three clinical trials for production of a covid19 vaccine and after receiving the sequence for the spike protein um they were able to produce a vaccine within 20 days so they had it on hand it’s just that you need all that time to make sure it’s safe to uh distribute to the general population and that’s why those lengthy clinical trials are there so will we get one during this pandemic or or are we going to have to wait some years until we see a plant-based vaccine for for whatever the disease may be oh yeah well i mean let’s see how long the pandemic lasts right um but uh i i would say there’s there’s some promising candidates that are being produced by medical in north america um they have a covid19 vaccine which is in phase three clinical trials which means i mean it it’s i would expect uh an announcement about that sometime this year i think but um who knows how how long these things take they also have another vaccine quadrivalent flu vaccine that they have in production which is also in phase three clinical trials so i think it’s a really exciting time and i i think it’s it’s likely that we’ll be seeing a plant-based vaccine in the near future yeah just briefly as well can can you eliminate the need for uh animal testing for these vaccines uh so that the process is 100 vegan uh so i don’t know about that part um because uh when you’re going to clinical trials you’re putting this vaccine into human participants in the trial and before that step you want to really test it on a living system so you can be sure that it’s safe before it’s going in in a real life person’s arm so i don’t see a pathway towards eliminating the use of animals maybe sometime in the future when you can properly mimic those systems but at this point no i don’t think we can eliminate animals from the process zachary leblanc from qut queensland university of technology in brisbane australia thank you very much for being on the show well thanks for having me take care ben now here’s an interesting question on the delta variant but i’ll let derek williams answer that for you what makes people with the delta variant so much more contagious in trying to answer this i think that we first need to go back to a term that once got a lot of air time but that many of you have probably since forgotten and and that’s the basic reproduction number of a pathogen or it’s are not now the r naught describes the average number of people that an infected person will infect in turn in an unexposed unvaccinated population when it first hit the ancestral coronavirus had an r naught of around two to three so each infected person on average infected two to three others but the original virus has since mutated into a range of variants among them the delta variant and and it’s a lot more transmissible with an r naught that’s estimated to be twice as high or or maybe even higher of course a lot more people are now largely immune to the virus due to vaccination or previous infection so each new delta patient isn’t actually infecting twice as many others but still people who get the delta variant are a lot more contagious than those who have other variants of the virus so what exactly has raised the r naught in the delta variant well researchers think that two changes in particular are probably behind its increased transmissibility the first involves a set of mutations that they say have altered the structure of the spikes that dot the outer surface of the virus the spikes are what allow the virus to latch on to receptors on a cell’s outer membrane and break into it and and scientists believe that changes to the delta variant spikes have made that break in process easier the second change involves how much of the virus is being produced by cells one study found that delta variant patients had viral loads that were around a thousand times higher than what’s found in those infected with the original virus with that massive replication also possibly happening a lot faster all of those factors scientists think are contributors to making the delta variant one of the most infectious respiratory diseases out there [Music] see you next time
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Plant-based vaccines for COVID-19 and other viruses | COVID-19 Special

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