IgE antibody-specific activity in human allergic disease

Area of Science:

• Immunology
• Allergology

Background:

• Immunoglobulin E (IgE) antibody concentration, affinity, clonality, and specific activity influence allergic symptom development.
• High IgE-specific activity (>3-4%) may hinder allergy symptom resolution in patients undergoing anti-IgE therapy (Omalizumab).

Purpose of the Study:

• To investigate the variability of IgE antibody specific activity concerning age, allergen specificity, and total serum IgE levels.
• To determine if IgE-specific activity influences effector cell mediator release extent and rate.

Main Methods:

• Analysis of 18,950 paired total IgE and allergen-specific IgE antibody data from 3,614 allergic subjects across 182 allergen specificities.
• A prospective, double-blind, placebo-controlled clinical study of anti-IgE therapy in cat-allergic subjects.

Main Results:

• IgE-specific activity fraction depends on age, epitope specificity, and total serum IgE; younger individuals with lower total IgE tend to have higher ratios.
• Hymenoptera venom, peanut, and milk elicited the highest frequencies of IgE-specific activities >4%.
• In anti-IgE therapy, IgE-specific activity remained constant despite rising total IgE; lower ratios (<2.5%) correlated with faster histamine release reduction.

Conclusions:

• IgE-specific activity is a variable influenced by age, IgE heterogeneity, and total serum IgE.
• This activity impacts effector cell mediator release and, consequently, allergic symptom induction.
• Lower IgE-specific activity may predict better outcomes with anti-IgE therapy due to more rapid loss of surface-bound allergen-specific IgE.