介绍:
It's a pleasure to be here in Edinburgh, Scotland, the birthplace of the needle and syringe. Less than a mile from here in this direction, in 1853 a Scotsman filed his very first patent on the needle and syringe.His name was Alexander Wood, and it was at the Royal College of Physicians. This is the patent. What blows my mind when I look at it even today is that it looks almost identical to the needle in use today.Yet, it's 160 years old.
0:43
So we turn to the field of vaccines. Most vaccines are delivered with the needle and syringe, this 160-year-old technology. And credit where it's due -- on many levels, vaccines are a successful technology.After clean water and sanitation, vaccines are the one technology that has increased our life span the most. That's a pretty hard act to beat.
1:11
But just like any other technology, vaccines have their shortcomings, and the needle and syringe is a key part within that narrative -- this old technology. So let's start with the obvious: Many of us don't like the needle and syringe. I share that view. However, 20 percent of the population have a thing called needle phobia. That's more than disliking the needle; that is actively avoiding being vaccinated because of needle phobia. And that's problematic in terms of the rollout of vaccines.
1:45
Now, related to this is another key issue, which is needlestick injuries. And the WHO has figures that suggest about 1.3 million deaths per year take place due to cross-contamination with needlestick injuries. These are early deaths that take place.
2:02
Now, these are two things that you probably may have heard of, but there are two other shortcomingsof the needle and syringe you may not have heard about. One is it could be holding back the next generation of vaccines in terms of their immune responses. And the second is that it could be responsible for the problem of the cold chain that I'll tell you about as well.
2:23
I'm going to tell you about some work that my team and I are doing in Australia at the University of Queensland on a technology designed to tackle those four problems. And that technology is called the Nanopatch. Now, this is a specimen of the Nanopatch. To the naked eye it just looks like a squaresmaller than a postage stamp, but under a microscope what you see are thousands of tiny projectionsthat are invisible to the human eye. And there's about 4,000 projections on this particular square compared to the needle. And I've designed those projections to serve a key role, which is to work with the skin's immune system. So that's a very important function tied in with the Nanopatch.
3:13
Now we make the Nanopatch with a technique called deep reactive ion etching. And this particular technique is one that's been borrowed from the semiconductor industry, and therefore is low cost and can be rolled out in large numbers.
3:28
Now we dry-coat vaccines to the projections of the Nanopatch and apply it to the skin. Now, the simplest form of application is using our finger, but our finger has some limitations, so we've devised an applicator. And it's a very simple device -- you could call it a sophisticated finger. It's a spring-operated device. What we do is when we apply the Nanopatch to the skin as so -- (Click) -- immediately a few things happen. So firstly, the projections on the Nanopatch breach through the tough outer layer and the vaccine is very quickly released -- within less than a minute, in fact. Then we can take the Nanopatch off and discard it. And indeed we can make a reuse of the applicator itself.
4:22
So that gives you an idea of the Nanopatch, and immediately you can see some key advantages.We've talked about it being needle-free -- these are projections that you can't even see -- and, of course, we get around the needle phobia issue as well.
4:36
Now, if we take a step back and think about these other two really important advantages: One is improved immune responses through delivery, and the second is getting rid of the cold chain.
4:49
So let's start with the first one, this immunogenicity idea. It takes a little while to get our heads around,but I'll try to explain it in simple terms. So I'll take a step back and explain to you how vaccines work in a simple way. So vaccines work by introducing into our body a thing called an antigen which is a safe form of a germ. Now that safe germ, that antigen, tricks our body into mounting an immune response,learning and remembering how to deal with intruders. When the real intruder comes along the body quickly mounts an immune response to deal with that vaccine and neutralizes the infection. So it does that well.
5:29
Now, the way it's done today with the needle and syringe, most vaccines are delivered that way -- with this old technology and the needle. But it could be argued that the needle is holding back our immune responses; it's missing our immune sweet spot in the skin. To describe this idea, we need to take a journey through the skin, starting with one of those projections and applying the Nanopatch to the skin.And we see this kind of data. Now, this is real data -- that thing that we can see there is one projectionfrom the Nanopatch that's been applied to the skin and those colors are different layers. Now, to give you an idea of scale, if the needle was shown here, it would be too big. It would be 10 times bigger than the size of that screen, going 10 times deeper as well. It's off the grid entirely. You can see immediately that we have those projections in the skin. That red layer is a tough outer layer of dead skin, but the brown layer and the magenta layer are jammed full of immune cells. As one example, in the brown layer there's a certain type of cell called a Langerhans cell -- every square millimeter of our body is jammed full of those Langerhans cells, those immune cells, and there's others shown as wel
