Green our vaccines! Part II

While poop jokes are all in good fun here in the US (and in other developed parts of the world), diarrhea really isnt all that funny for most of the planet. Dehydration due to diarrhea is the second leading cause of death for babies, worldwide (it was #1 until we started aggressive education/re-hydration efforts). Hundreds of thousands of people die from cholera and enterotoxigenic E. coli (ETEC) infection every year.

Thats not funny :(

So scientists have been working really hard to create vaccines to cholera and ETEC, and a group of folks have figured out a really cool strategy-- genetically modify rice to express part of the cholera toxin. When someone eats the vaccine rice, their immune system gets a cheat-sheet for what the real toxin will look like. Their body starts secreting IgA, antibodies that recognize the toxin, in their mouth/tears/digestive tract/breast milk. If that person is exposed to real cholera, they already have antibodies around to neutralize the toxin, thus are able to prevent or limit the extent of that infection!

BONUS: If the person who gets the vaccine is a breast-feeding mom, these beneficial anti-cholera-toxin IgA antibodies are passed down to their babies via breast milk, thus also protect their babies from cholera!

BONUS BONUS: This plant-based vaccine strategy is also beneficial because it requires no sterile needles, no freezing/refrigeration, and the vaccine would have a ridiculous shelf-life of at least three years.

What have the scientists named this awesome GMO-rice-product?


*gag*... *gaaaag* Oh gross... Christ... LOL! I know its supposed to be 'muco' for 'mucosal immunity', but all I think is 'mucus', and I dont want to eat that... uuuuugh... LOL!

Ignoring the gross name, theyve put a lot of effort into this vaccine-- here is just their latest paper, 'proving' that the secreted anti-cholera-toxin IgA antibodies are why this vaccine works:

Secretory IgA-mediated protection against V. cholerae and heat-labile enterotoxin-producing enterotoxigenic Escherichia coli by rice-based vaccine

These studies were done in mice. Why did the researchers go back to mice, even though theyve got a non-human primate study under their belt? Well, one of the reasons is that they wanted to establish exactly why their vaccine works. They thought it was because of anti-cholera-toxin IgA being secreted into the intestines, but they wanted to know for sure:

... despite the generally accepted concept that mucosal vaccine induces antigen-specific secretory IgA (SIgA) production, thus providing a first line of specific defense against mucosal infectious diseases, there is no direct evidence that the CTB-specific SIgA production induced by MucoRice-CTB is essential for protection against CT-induced diarrhea.

We use lots of mice in research that are essentially clones of one another. This makes it a little easier to genetically modify them to have certain deficiencies in pathways we want to study. We cant do this with non-human primates. So these folks generated mice that can make IgA, but they cant secrete it. So the mice still have lots of IgA antibodies floating around in their bloodstream, but they never show up in their tears/breast milk/etc.

If you need the antibodies to be secreted for this vaccine to work, then these non-secretor mice will get sick.

If it doesnt really matter whether antibodies are secreted (lets say IgG antibodies can do all the work on their own), then these non-secretor mice will still be protected.

Heres what happened:
The non-secretor mice were not protected against the effects of cholera or E. coli toxin (which has a similar structure to the cholera toxin, the antibodies are cross-reactive), even though they got the vaccine. The mice that could secrete IgA normally were protected. The non-secretor mice still made a ton of anti-cholera IgA, but since it couldnt get out into their intestines, it didnt do them any good.

Secondly, the mice needed to get this vaccine orally to get a really nice IgA response, thus the best protection. When the vaccine was injected instead of eaten, even the normal mice still got sick (though to a lesser degree than the mice who got no vaccine).

Thirdly, immunity against cholera and E. coli toxins lasted at least 6 months, and responded well to boosters (their immune systems remembered what they were seeing-- very important). While six months doesnt seem very long to you and me, thats like, a third (or more) of the lifespan of a mouse. And even if it is only 6 months in humans too, this vaccine would be so cheap and easy to store, boosters wouldnt really be that big of an issue-- especially in outbreak scenarios (just give a booster to everyone), or even just those of us in the US who want protection when we go overseas for vacations (who gets to go on vacation for over 6 months at a time??).

Very cool research with green vaccines. GMO plants and vaccines might literally save your butt in the near future.

More like this

GMO plants and vaccines might literally save your butt in the near future.

No, it's Frankenfood, it's eeeeevil.

You know what I wish was done everywhere? Food irradiation.

So many millions of people die from inadequate sanitation and unsafe food, and it is all totally preventable if people would abandon their superstitions.

The European Union has been particularly backward on this; the United States has creationism, but no monopoly on irrationality.

By Gabriel Hanna (not verified) on 28 Jul 2010 #permalink

My generation got their polio sugar cube, future kids have to look forward to rice pudding.

Can I get some General Tso's chicken with my vaccine?

I was all ready to start complaining about how this doesn't make sense because of oral tolerance etc, but I think I figured it out. CTB can invade cells on it's own, and is an adjuvant itself. But still, you can link insulin to CTB and delay or prevent NOD mice from getting diabetes, so there's some amount of tolerance induction.

Still, super cool.

Wow, that is a dreadful name. Scientists suck at names and marketing, really....

Wow, I had never heard about this particular form of GMO before - very cool.

Wow. I know we scientists tend to be tone-deaf when it comes to branding, but I can't believe anyone would go with MucoRice. Especially when "Mucosal Immunity Rice" can so obviously be shortened to "MI-Rice" Nice, catchy, easy to say, and no nauseating connotations. Plus, it evokes connotations of personal ownership ("my rice") and high-tech (sounds a bit like iPod, iPhone, iPad, etc.).

Hopefully it's not too late for rebranding.

You know what I wish was done everywhere? Food irradiation.

So many millions of people die from inadequate sanitation and unsafe food, and it is all totally preventable if people would abandon their superstitions.

The cognizant criticism of food irradiation I've heard about is that having it available to kill germs is likely to lead to companies slacking off in health and safety elsewhere in the production process, particular in terms of animal welfare (and it's not clear to me that the irradiation would affect toxins already secreted, though this could be glossed over in presentations to key nonexperts >.>). That's a non-trivial concern but I think it could be worked around with proper regulatory oversight...

Last night I had another thought about anti-cholera rice. I was talking with a cholera researcher the other night at the Skeptic's meeting and we were talking about how the well-fed westerners grouse about plant and other tech for other societies, and how the paternalistic charms of the "simpler folks" speak to those foodies.

This researcher brought to my attention a recent incarnation of this, in the form of a movie. She said something like: Yeah, they think it's all Eat. Pray. Love. It's not: It's Eat. Pray. Love. Cholera.

OMFZFG!!! Franken-foods and vaccines AT THE SAME TIME!!! Teh ANTI-CHRIST IS COMMING!

By theshortearedowl (not verified) on 29 Jul 2010 #permalink

I assume that MucoRice has to be eaten raw to be effective, that cooking would denature the proteins and make them not the right kind of immunogenic.

"all I think is 'mucus', and I dont want to eat that... uuuuugh... LOL!"

I am a ten year old child and I just knocked my hippie anti-vax mom over to get to a box of
*drum roll*

Frankenstein Snot TM.

Now with with two scoops of boogers.

Alert PepsiCo, it's another opportunity to do well by doing good.

By Prometheus (not verified) on 29 Jul 2010 #permalink

So...the mice that ate this MucoRice totally got autism, right?

By Scientizzle (not verified) on 29 Jul 2010 #permalink

The cognizant criticism of food irradiation I've heard about is that having it available to kill germs is likely to lead to companies slacking off in health and safety elsewhere in the production process, particular in terms of animal welfare...

Why does this argument not apply to bleach? It's silly, isn't it: don't adopt a technique that will make food safer because then everyone will think their food is safe and get careless about keeping it safe?

That's like saying that seat belts make drivers more careless about avoiding collisions so they'll get in more accidents, and so we should not put seat belts in cars.

That's not a legitimate criticism of the technology.

Not to go completely off topic or anything.

By Gabriel Hanna (not verified) on 29 Jul 2010 #permalink

I'm not a food scientist, so please forgive the question: am I eating food that's been sterilized with bleach?

You use bleach to clean surfaces. But if we just use bleach to clean everything, we'll just forget to cut chicken on a separate table from vegetables and be at a higher risk of cross contamination, apparently.

By Gabriel Hanna (not verified) on 29 Jul 2010 #permalink

" I eating food that's been sterilized with bleach?"


Bleached rice just means it looks bleached because it has been completely husked and polished.

Bleached flour uses a small amount of organic peroxide to keep the flour from yellowing and to release gluten so your bagels are bouncy.

Long before it hits your face the peroxide has turned into air and water.

People freak out over enriched flour too but it is awesome and a very cool science story:

By Prometheus (not verified) on 29 Jul 2010 #permalink

Abbie, you need an endless threat to post random info !!

Ebola found in Guinea Pig genome

So does that make it an ERV, or does it not work like that for RNA viruses ?

By Rorschach (not verified) on 29 Jul 2010 #permalink


By Rorschach (not verified) on 29 Jul 2010 #permalink

LOL! Dont be disappointed! See I already have a post up for you, LOL!

This *is* really kinda weird though, actually, so thanks for the H/T!

No worries, didn't realise it was 2 different labs....
Then again, the first time Marburg/Ebola was isolated in 1967 was when 3 labs were cutting up Cercopithecus monkeys, in Marburg, Frankfurt and I think Belgrade, at the same time !

so your bagels are bouncy.

Bouncy? Did you forget to boil them?

Cool beans (y'know, to go with the rice).

They did this a few years ago, adding vitamin A to rice to make "Golden Rice." To fight blindness due to vitamin A deficiency

Problem #1- they didn't check which strain of rice was dominant in the target region, and picked one that nobody liked. Any idea if they did their research this time?

Problem #2- the GMO rice was patented, which meant buying expensive seed. Not an option for subsistence-level. Is this rice going to be provided? Are people going to be permitted to make their own seed? Is this rice as hardy as the native rice? Is this rice a one-off?

Problem #3- the golden rice was literally a funny yellow-gold colour. People didn't want to eat it because it didn't look like rice. Hopefully not an issue this time around.

Problem #4- the EU and the US have rules about GMOs. If a country grow any form of GMO, it devalues ALL their crops. Seriously! That plus farm subsidies means that people who want to sell their crop, or who live in an area where other crops are grown for export will have no choice but to oppose this.

I love biotechnology. I think it can solve world hunger, produce vaccines, prevent disease.... but I think we ought to be using it at home first or people "out there" may get the impression that it's getting dumped on them because it's not good enough for us***. We have the money to spare when things don't go as planned. We have the money to spend on public education. We have the money to blow on expensive seed and fertiliser.

*** I heard this many times in Africa- anecdotal, but worth thinking about.