Researching an asthma vaccine

In this RNZ programme, Researching an asthma vaccine, Amelia Nurse talks to Franca Ronchese and Graham Le Gros from the Malaghan Institute. They are looking into isolating the asthma immune response.

Duration: 18:39

Why asthma starts

We know a lot about asthma symptoms, but we don’t know how it starts and why it starts in the first months of life or at any time later in life. Our immune system is programmed to react efficiently when there’s a virus infection, and it’s quite specific. With asthma, the signals get mixed up. It could be that, with the level of hygiene in modern society and by removing certain parasites and bacterial infections, the immune system is not being trained in the right way.

TH2 cells

TH2 cells are associated with the immune system’s allergic response to a parasite. TH2 cells could be viewed as good cells that get confused. The TH2 response causes inflammation and damage to the lungs so that air can’t get in and out. TH2 cells have a memory, so once you’ve had your first asthma attack, they will continue to react in that way.

Dendritic cells

The dendritic cells are the immune system’s first line of defence. When the allergen is breathed in, the dendritic cells decide what immune response to start. This is usually a TH2 immune response that induces a lot of damage to the airways and is what we call an asthma attack. We use steroids that are blanket immune suppressive agents because we haven’t found a way to selectively suppress a TH2 immune response. It’s a good temporary measure to get the immune system to calm down but is not a long-term measure.

Using the killer cells

Research to find a better treatment involves dendritic cells and CD8 cells or killer cells. Scientists think that killer cells can react to allergens and balance the reaction of the TH2 cells. In their experiments, mice have been given a vaccine that activates the killer cells and stops the TH2 responses. However, they don't know yet whether this would work in patients. There is still a lot of research to do, but potentially in 10 years, there could be a vaccine for asthma.

Programme details: Our Changing World