Question of the Month

Test your knowledge with our Question of the Month, organized by our Patient & Professional Relations (PPR) Committee! These allergy trivia questions and answers are a fun way to learn fun ENT facts while keeping your knowledge sharp.

Question: Anti-IgE Therapy Nuance in Food Allergy

A 16-year-old with severe peanut allergy is undergoing oral immunotherapy (OIT). Due to frequent dose-limiting reactions, adjunctive therapy with Omalizumab is initiated.

Which of the following best explains how omalizumab improves tolerability during OIT?

A. It irreversibly depletes mast cells in gastrointestinal mucosa
B. It reduces FcεRI receptor expression on mast cells and basophils over time
C. It blocks IL-4 and IL-13 signaling pathways
D. It increases allergen-specific IgG4 production directly
E. It inhibits eosinophil trafficking into the lamina propria

Correct Answer: B

Explanation:
Beyond binding free IgE, omalizumab leads to downregulation of FcεRI receptors on mast cells and basophils, decreasing cellular sensitivity to allergen exposure. This is key in improving safety during OIT.

• A: No mast cell depletion
• C: That’s more consistent with dupilumab
• D: IgG4 changes occur indirectly with OIT, not directly via omalizumab
• E: More related to IL-5–targeted therapies

Key Sources

• FDA approval and mechanism summary for Omalizumab (updated for food allergy indication, 2024)
• AAAAI practice updates on biologics in food allergy
• EAACI Food Allergy Guidelines
• Wood RA et al.
  “A randomized, double-blind, placebo-controlled study of omalizumab combined with oral immunotherapy for multiple food allergies.”
  The Lancet Gastroenterology & Hepatology, 2016
• Sampson HA et al.
  “Mechanisms of action of anti-IgE therapy.”
  Journal of Allergy and Clinical Immunology (JACI)