Vaccines have had an enormous impact on human health worldwide, but they’re not shelf stable — they need to be refrigerated from the time they’re made to the time they’re used. Transporting them overseas and on trucks to remote villages is a huge challenge that means that some parts of the world just don’t have access at all.
But what if you could mix together everything you need to manufacture a vaccine in a tube to make it in your own back pocket?
That’s the goal for Keith Pardee, assistant professor of pharmacy at the University of Toronto. He wants to extend the reach of healthcare, and that starts with making healthcare tools available without the clinical labs that are only accessible in urban centres.
“The big idea in our lab is that we can run gene circuits outside of cells,” explains Pardee. “We do that by basically making a soup out of bacteria. So there’s no cells, it’s just all the machinery that makes a cell work, and we use that machinery to run gene circuits in a test tube.”
Taking the machinery out of the cells means that it’s easier to transport and simple to use anywhere.
“With our system, we’ve freeze-dried the ability to make that vaccine, and you ship it just like you can do with ramen noodles or soup,” adds Pardee. “You just add water at the end, and you put the DNA that codes for the vaccine protein in and warm it up to your body temperature. And in a few hours you’ll have the vaccine.”
This on-demand approach means that these shelf-stable kits could be ready to respond to an outbreak, generating hundreds of thousands of doses of vaccines or other protein-based drugs in a short period of time. These tools would normally be restricted to hospitals or other specialized centres, but with only water and the warmth of body temperature needed to sustain the reaction, a back pocket becomes a laboratory.
Pardee is also creating rapid diagnostic tools that can easily be applied to any disease-causing micro-organism by using its genes as a barcode. His work recently helped diagnose the Zika virus using a paper-based test.
The sensing molecules are freeze-dried onto a piece of paper the size of a stamp, and a user applies a small saliva, urine, or blood sample. In about an hour, the test paper changes colour to purple if Zika is present. Each test costs about a dollar to make and doesn’t require any specialized equipment or training to read.
“As the world’s population is growing, we have billions of people who need healthcare, but many of them live on under three dollars a day,” says Pardee. “So what we use this for is to extend the reach of healthcare to populations that don’t have access currently.”