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Immunology 2018
J u l y 0 5 - 0 7 , 2 0 1 8
V i e n n a , A u s t r i a
Page 110
Journal of Clinical Immunology and Allergy
ISSN 2471-304X
1 5
t h
I n t e r n a t i o n a l C o n f e r e n c e o n
Immunology
G
lobal prevalence of allergic diseases has been on the rise for the last 30 years. In Canada, this upward trend in allergic
diseases has resulted in over 3 million Canadians being affected by allergic asthma. Asthmatic airway inflammation
is initiated by the release of inflammatory mediators (histamine) released by granulocytic cells (mast cells and basophils).
However, immunoglobulin E (IgE) antibody is also necessary for the initiation of the allergic cascade, and IgE is produced and
released exclusively by memory B cells and plasma cells. Acute allergen exposure has also been shown to increase IgE levels
in the airways of patients diagnosed with allergic asthma; however, more studies are needed to better understand local airway
inflammation. Although regulatory B cells (Bregs) have been shown to modulate IgE-mediated inflammatory processes in allergic
asthma pathogenesis, particularly in mouse models of allergic airway disease, the levels and function of these IgE+ B cells and
Bregs remain to be elucidated in human models of asthma. Thus, the overall objective for this research was to investigate the
frequency of IgE+ B cells and Bregs in allergic asthma, and the kinetics of these cells after allergen exposure. Our research shows
that allergic asthmatics have elevated levels of IgE+ B cells in the airways, that can be further increased after allergen exposure.
Therefore, local B cell production of IgE in the lungs may be an important source of IgE for initiation of acute inflammatory
responses in allergic airways. Additionally, we showed that Bregs were lower in the blood of allergic asthmatics compared to
controls, highlighting a possible dysregulation of this regulatory cell type in allergic asthmatics, which may contribute to disease
pathology. Furthermore, after whole lung allergen challenge Bregs decreased in the bone marrow with a co-incident increase in
the blood and sputum of allergic asthmatics. This pattern reflects potential trafficking of these cells from bone marrow to the
airways after exposure to allergic stimuli. However, further functional studies are warranted. Taken together, the findings of this
research highlight the local compartmental changes in IgE+ B cells and Bregs following allergen challenge of allergic airways.
Better understanding the temporal and compartmental shifts in B cell subpopulations, particularly IgE+ B cells and Bregs, may aid
in future development of therapeutics
olivejp@mcmaster.caIgE+ and regulatory B cells in allergic asthmatic
subject following allergen inhalation
John-Paul Oliveria
1, 2
1
McMaster University, Canada
2
Stanford University, California, USA
Insights Allergy Asthma Bronchitis 2018, Volume: 4
DOI: 10.21767/2471-304X-C1-003