Once these molecule parts, known as epitopes, have been identified and isolated, they can potentially be targeted by a vaccine that lessens the immune response they trigger.
Molecular biologist Takashi Inui from Osaka Prefecture University said, "We want to be able to present small doses of these epitopes to the immune system to train it to deal with them, similar to the principle behind any vaccine,"
His researchers focussed on the dog allergen called Can f 1, which is believed to be responsible for 50-75 percent of reactions in people who are allergic to dogs.
For someone with a dog allergy, the epitopes the scientists are looking for can be thought of as being like puzzle pieces that fit with matching pieces constructed by our immune system – antibodies carried by B cells, or T Cells – for easy identification, essentially hunting down the cause of the allergic reaction.
This epitope-led way of developing a vaccine is unusual, and if scientists are able to make it happen with regards to dog allergies, the same process might be used to develop other types of vaccines in the future.
"These allergens can cause severe allergic reactions, such as asthma, allergic rhinitis, and allergic conjunctivitis in 5-10 percent of the population," write the researchers.
"As contact between dogs and humans becomes more frequent and intimate, dog allergies have become increasingly prominent worldwide, particularly in advanced nations."
If you're allergic to dogs you'll find some useful ways to reduce the allergen load and minimise the effects of pet allergen in your home here.