Quantitative analysis of peripheral allergen-specific B lymphocytes in asthma

Area of Science:

• Immunology
• Allergy and Asthma Research

Background:

• Asthma is a chronic respiratory disease characterized by airway inflammation and hyperresponsiveness.
• Peripheral allergen-specific T cells have been implicated in predicting bronchial responses in asthma.
• The role of B cells committed to producing allergen-specific immunoglobulin E (IgE) in asthma remains less understood.

Purpose of the Study:

• To investigate the quantitative role of peripheral blood B cells committed to producing allergen-specific IgE in asthma.
• To determine if the frequency of these B cells correlates with bronchial hyperresponsiveness and allergen-induced responses in asthmatic patients.

Main Methods:

• Enumeration of peripheral blood B cells committed to allergen-specific IgE production using limiting dilution microcultures of Epstein-Barr virus (EBV)-transformed B cells.
• Allergen inhalation challenge performed in 23 asthmatic patients sensitized to Dermatophagoides pteronyssinus.
• Comparison of B cell frequencies between asthmatic patients and 11 healthy controls, and between asthmatics with or without a late-phase bronchial response.

Main Results:

• No significant difference was observed in the frequency of B cells committed to allergen-specific IgE production between asthmatic patients and controls.
• The frequency of these B cells did not differ between asthmatic patients who exhibited a late-phase bronchial response and those who did not.
• No correlation was found between the frequency of allergen-specific IgE-producing B cells and the severity of the bronchial response to allergen challenge.

Conclusions:

• In quantitative terms, peripheral B cells committed to producing allergen-specific IgE are not as relevant as T cells in the development of asthma.
• The study suggests that T cells play a more significant role in the immediate and late asthmatic responses compared to these specific B cell populations.