Quantitative and Qualitative Estimations of IgE Bound to Basophil Leukocytes from Hay Fever Patients

Abstract

IgE was removed from human basophils of 4 nonatopic persons and 10 hay fever patients allergic to timothy grass pollen by treating the cells with buffer to adjusted pH 4. IgE could be removed and refixed to the same cells. Refixation was demonstrated by immunofluorescence and by the ability of basophils to release histamine on exposure to timothy pollen. Removed total IgE and specific IgE directed against timothy pollen were estimated, and a linear correlation to the level of total IgE and specific IgE in serum was found. The total number of IgE molecules per basophil was calculated to be in the range of 30,000 to 300,000, and timothy‐specific IgE constituted 4%‐15% of the total IgE molecules on the cells. It was furthermore established that specific cell‐bound IgE was linearly correlated to the pollen concentration releasing 20% of the histamine contents of the basophils. Separated IgE from sensitized and nonsensitized basophils could be bound to basophils from other patients, resulting in a change in cell sensitivity. This could be ascribed to additional binding to free cell receptors as well as to a partial replacement of bound IgE. Basophils from nonatopic persons could not be sensitized by incubation with surface IgE from atopic persons. The results indicate that acid treatment is a simple method suitable for removing IgE from basophils. This IgE is intact and can be quantitated.

Diagnostic Tests Based on Human Basophils: Potentials, Pitfalls and Perspectives

“…This obstacle can be overcome by combining basophils from a non-sensitized person with serum containing specific and relevant IgE antibodies. In its original form, basophils from adult donors were stripped of their original IgE by a brief treatment with low pH, followed by incubation with the sensitizing serum [49, 50]. More recently, cord blood basophils have been used as recipient cells, which has the advantage of eliminating the low pH IgE dissociation step, which may interfere with the biological functions of the cells [Dr.…”

Signaling through the high affinity IgE receptor and conditions able to modify IgE‐antigen responsiveness of mast cells

“…This receptor becomes active after the crosslinking mediated by the interaction of IgE with a specific allergen (antigen) [7]. In people with a tendency to allergies (atopic individuals), IgE levels usually are elevated [8], and the FceRI of their mast cells are occupied by IgE antibodies ready to respond to the presence of antigen [9]. When allergen appears, receptor activation induces inflammatory mediator release even with very low amounts of antigen, producing the symptoms of any of the most common allergic diseases, such as rhinitis, allergic asthma, atopic eczema or, even, anaphylactic shock [10].…”