Well Saturday was such a day.
While at a friend’s party I found myself chatting to the presenter of science podcast/radio show (“Diffusion Science Radio” downloadable at iTunes or www.diffusionradio.com (an excellent podcast by the way – well worth listening to)) and he
mentioned how llamas plus rice might help save 100s of THOUSANDS OF LIVES. I found myself fighting not to run from the party that very second to learn more and then spent every spare minute of the remaining weekend reading about Llamas, Llamas, Llamas.
So there is this virus. Rotavirus. Nasty, evil, poopy virus. Yes poopy. It causes diarrhoea. Nasty diarrhoea. In the developed world it can frequently cause hospitalisation. In the developing world, it leads to half a million children deaths a year. This is indeed a bad virus. So imagine the medical worlds delight when two highly effective vaccines were developed protecting 85%+ of those vaccinated. Delighted indeed, well almost delighted. There’s a problem, in the developing world where it is really needed, malnutrition and HIV damage people’s immune systems and this can reduce the vaccines effectiveness to less than 60%. That means, even with high levels of vaccination, there will still be a lot of deaths. |
Then a long came the Llama
Our simplest antibodies look like this. Made up of 4 polypeptide chains. 2 identical light chains (the short ones) and two identical heavy chains (the other ones). Crucially, the important, business end of the molecule, the bits that actually attaches to viruses and other nasties - the antigen binding sites, are each made up of BOTH chains. This means any change in their environment, that causes these chains to separate, destroys the antibodies activity. THIS is why it is so sensitive. Added to this, if you want to produce antibodies in a transgenic organism you need both the light chain and heavy chain genes expressed in the right amount AND their chains to fold together correctly - no easy feat. So what's different about the llama antibody? |
Also being made of just one type of polypeptide chain, its gene can easily be cloned and put into something else....
So what scientists have done is find llama antibodies that recognise and neutralise rotavirus and clone the genes that make them (well actually a shortened gene that just makes the binding bit) and put the gene into rice! So now we have rice that makes anti-rotavirus antibodies! This can then be cooked and eaten and SAVE LIVES! It's been tested on mice and seems to work. The llama antibodies made in yeast cells have also been shown to help people. So will the llama-rice (called un-snappily MucoRice-ARP1) treatment work in people? Time will tell. Its a long slow process testing and bringing a transgenic crop to use in the general public even if it could save, many, many lives. It could still be 10 more years before it becomes a treatment. But when/if it does Llamas will be doing more than just saving a day! |
Disclaimer: Llama faces do look silly. Its OK to laugh.