Uppsala University Study Shows More Precursor Cells To Mast Cells In Pollen Season

The frequency of precursor cells to mast cells in the blood circulation is higher in asthma patients during the birch pollen season than outside. This is shown by a new study from Uppsala University published in the scientific journal Allergy.

The study, which was part of Abigail Alvarado-Vazquez’s thesis and which is a collaboration with researchers at the Academic Hospital in Uppsala, shows that the frequency of precursor cells to mast cells in the blood increases with allergen exposure in asthma patients. It can be linked to increased asthma and allergy symptoms and reduced asthma control.

– This also means that precursor cells to mast cells in blood are interesting as a biomarker for asthma, says Jenny Hallgren Martinsson, Department of Medical Biochemistry and Microbiology at Uppsala University.

For many years, researchers have studied how the immune system, including mast cells, react to exposure to allergens. It has also been described that mast cells accumulate in different regions of the lungs in patients with asthma. Jenny Hallgren Martinsson’s research group has previously shown that this is due to precursor cells to mast cells migrating to the lungs from the bone marrow via the blood. In 2016, they were the first research group in the world to show that precursor cells to mast cells are also found in the blood of humans, and in a follow-up study they showed that a high incidence of precursor cells to mast cells was found in patients with asthma who had lower lung function.

In the new study, the research group examined patients with birch pollen-induced asthma both during the birch pollen season and outside the season. It was found that the presence of precursor cells to mast cells in the blood circulation was higher during the birch pollen season than out of season. In addition, it was the people who had more severe symptoms and a lower degree of asthma control during the birch pollen season that had the highest prevalence of precursor cells to mast cells.

– This indicates that if patients with allergic asthma are exposed to allergens, the bone marrow is stimulated to temporarily release more precursor cells to mast cells into the blood, says Jenny Hallgren Martinsson.