04/28/2026
🧬 Understanding Antibody Responses in Food Sensitivities
🔬 IgG1–3 & Inflammatory Reaction:
IgG antibodies can activate the pro-inflammatory complement cascade, contributing to chronic inflammatory conditions.
⬆️ High IgG levels (Class II or higher) may overload receptors and drive inflammation
⬇️ Low IgG levels (Class 0/I) are typically associated with tolerance
🛡️ IgG4 & Inflammatory Reaction:
IgG4 does not typically activate complement and instead acts as a “blocking antibody” for IgE.
✔️ Generally considered protective, not inflammatory
⚠️ Elevated IgG4 may reflect higher exposure; further evaluation of IgE reactivity may be considered, and dietary changes can be assessed in a clinical context
🌿 IgA & Inflammatory Reaction:
Serum IgA can also activate the pro-inflammatory complement system.
➡️ It is converted into secretory IgA at the gut lining and measured in stool
➡️ Plays a key role in mucosal immunity and gut barrier function
💡 Different antibodies, different clinical implications; understanding these patterns can help support more informed clinical decision-making.