Send to

Choose Destination
J Allergy Clin Immunol. 2012 Sep;130(3):663-670.e3. doi: 10.1016/j.jaci.2012.04.006. Epub 2012 May 13.

Allergen specificity of IgG(4)-expressing B cells in patients with grass pollen allergy undergoing immunotherapy.

Author information

Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom.



Serum IgG(4) responses to allergen immunotherapy are well documented as blocking allergen binding to receptor-bound IgE on antigen-presenting cells and effector cells, but the molecular characteristics of treatment-induced IgG(4), particularly in relation to expressed antibody, are poorly defined.


We aimed to clone and express recombinant IgG(4) from patients receiving grass pollen immunotherapy using single B cells to obtain matched heavy- and light-chain pairs.


IgG(4)(+) B cells were enriched from blood samples taken from 5 patients receiving grass pollen immunotherapy. Matched heavy- and light-chain variable-region sequences were amplified from single IgG(4)(+) B cells. Variable regions were cloned and expressed as recombinant IgG(4). Binding analysis of grass pollen-specific IgG(4) was performed by using surface plasmon resonance. Functional assays were used to determine IgE blocking activity. In a separate experiment grass pollen-specific antibodies were depleted from serum samples to determine the proportion of grass pollen-specific IgG(4) within total IgG(4).


Depletion of grass pollen-specific antibodies from serum led to a modest reduction in total IgG(4) levels. Matched heavy- and light-chain sequences were cloned from single IgG(4)(+) B cells and expressed as recombinant IgG(4). We identified an IgG(4) that binds with extremely high affinity to the grass pollen allergen Phl p 7. Furthermore, we found that a single specific mAb can block IgE-mediated facilitated allergen presentation, as well as IgE-mediated basophil activation.


Although increases in IgG(4) levels cannot be wholly accounted for within the allergen-specific fraction, allergen immunotherapy might result in the production of high-affinity allergen-specific blocking IgG(4).

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center