The role of regulatory B cells in allergic asthma

Bronchial asthma, or asthma for short, is a chronic disease in which the respiratory tract is permanently inflamed and reacts particularly sensitively to various stimuli. In allergic asthma, these allergens are, for example, pollen, animal hair or house dust mites. An important role of effective regulatory B cells in the development of allergic asthma could be proven by a DZL team led by Prof. Gesine Hansen from the Clinic for Pediatric Pneumology, Allergology and Neonatology.

Asthma is a chronic lung disease in which the airways are permanently inflamed. In this disease, the lung reacts extremely sensitively to various allergens. The reaction leads in some cases to narrowing of the bronchi, whereby the typical symptoms, like wheezing, shortness of breath, difficulty breathing or coughing occur. Worldwide, approximately 339 million people suffer from asthma and each year about 250,000 people die of this disease (www.who.int). 
In recent years, the focus of research into allergic asthma has lain on the role of T cells in the inflammatory reactions of the airways. Latest studies now also concentrate on the B cells as mediators between allergy and tolerance development. Scientists in the BREATH network, the Hannover site of the German Center for Lung Research, are currently investigating at Hannover Medical School (MHH) the role of B cells in asthma, both by studying blood samples from asthma patients as well as in experimental asthma models. 
Anika Habener, from Prof. Gesine Hansen’s working group, was able to show in an experimental asthma model that mice without B cells developed particularly severe asthma and particularly more severe respiratory distress than mice with B cells. 
The more severe form of asthma in B cell-deficient mice is primarily due to the lack of regulatory B cells, which  play a „modulatory“ role in the development of allergic inflammation, breathing difficulties and the structural remodeling of the lung. An essential part of this is the production of the messenger interleukin-10 (IL-10), as was shown in further experiments. Thus, the greater degree of severity of the asthma in B cell-deficient mice could again be reduced by transplantation of normal B cells. However, if B cells which cannot produce IL-10 were transplanted, this improvement did not occur. 
The results of the study show that B cells, particularly regulatory IL-10-producing B cells, have an important influence on the development and characteristics of the asthmatic condition. The role of B cells in people with asthma is also currently being studied and compared with the results from the mouse studies. For this purpose, blood samples from children and adults from the asthma cohort of the German Center for Lung Research (All Age Asthma Cohort - ALLIANCE) will be used.
Through this comprehensive research into the immunological principles of bronchial asthma in the mouse model and the transmission and confirmation of new findings on the role of the B cell in patients with asthma, in future new therapies for allergic asthma will be developed as well as preventive strategies that could possibly be used already in early childhood. 
 

Link to original publication:

Regulatory B cells control airway hyperreactivity and lung remodeling in a murine asthma model. Habener A, Happle C, Grychtol RM, Skuljec J, Busse M, Dalüge K, Obernolte H, Sewald K, Braun A, Meyer-Bahlburg A, Hansen G, J Allergy Clin Immunol.2020

 

Text: BREATH/AH,AB

Photo: Zinner

Anika Habener from the BREATH working group of Prof. Dr. Gesine Hansen