Novel Dust Mite Vaccine on Its Way
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What would be different about your vaccine that would allow it to work in just two or three doses?
At the moment, allergy vaccines contain just the allergen itself. We want to find an adjuvant to add that will boost the immune process and hopefully accelerate the vaccine effect. [An adjuvant is an agent added to a vaccine to increase or aid its effect.]
In infectious diseases, scientists have discovered that there are certain molecules associated with infectious bacteria that are particularly good at switching on the immune response and getting it going. So, apart from the actual antigens, which are necessary to recognize the organism and attack it, there are also molecules called innate stimulators, and they are used in adjuvants. For a long time, nobody really knew how they worked, but now we are starting to recognize how they work in molecular detail. We want to use these same innate stimulators that really get the immune system going – and potentially they have different stimulators for different types of immune responses, so we have some that we can recognize that alter the immune system into not reacting with an allergic response.
How will you test what to add to the vaccine?
We’re using sheep. In the first step of our research, we showed that we can induce in sheep the same kind of allergic response to house dust mite that some humans have. We’ve given them the allergen in their lungs and have shown that they have the same asthmatic-type response as humans. The next step is to vaccinate them to see what the effect is and compare it to normal, standard allergy vaccine treatment. Our sheep model is much more relevant to the human condition than mice.
I can’t help but wonder: what does a sheep having an allergic reaction look like?
Sheep are quite similar to humans, especially in the lungs. They actually develop the same lung constrictions and airway hyper-reactivity as humans and we can measure it in a very detailed way. We can also measure the allergen-specific IgE response.
What are your next steps?
We’ve established the model with sheep, and now we’re waiting for the next grant, with which we’ll use the model to do the vaccine study in the next two years …. Getting to human trials in the allergy area seems to be quicker than in infectious diseases. People could be trying the vaccine maybe even in the next five years.