FREE subscriptions for doctors and students... click here
You have 3 more open access pages.
IgG4 is usually formed following repeated immunization; it may be involved in allergy.
IgG4 may be absent in IgA deficiency.
In serum of healthy individuals, IgG4 antibodies comprise the smallest fraction (< 5%) of IgG antibodies (1)
IgG4 has been extensively studied in models of chronic allergen exposure (1)
- IgG4 antibodies possess exclusive structural and functional characteristics suggesting anti-inflammatory and tolerance-inducing effects
- in beekeepers naturally exposed to bee venon high levels of bee venom-specific IgG4 are found to play a protective role against severe hypersensitivity reactions triggered by the bee venom allergen phospholipase (PLA2)
- is in contrast to the situation in bee-venom allergic individuals that exhibit high titers of PLA2-specific IgE and are at risk of IgE-mediated anaphylaxis when stung
- increased IgG4-specific antibodies correlate with allergen tolerance and can be measured in tolerant animal laboratory workers chronically exposed to rodent allergens
- also seen in individuals undergoing AIT (allergy immunotherapy) for severe allergies, including wasp, cat, house dust mite and birch pollen allergies
- IgG4 are thought to exert their anti-inflammatory effect through competitive binding with IgE to the allergen, thereby preventing formation of IgE immune complexes and IgE-mediated activation of mast cells.
Serum IgG4 level
has been described to be the most sensitive and specific
laboratory test for the diagnosis of IgG4-Related Disease (IgG4-RD) (2)
that an elevated serum IgG4 level can be encountered in
other diseases such as pancreatic cancer, atopic diseases, and infections
- also note that serum IgG4 level
is elevated in up to 5% of the normal population
- Trampert DC et al.
On the role of IgG4 in inflammatory conditions: lessons for IgG4-related disease.
Biochimica et Biophysica Acta (BBA) - Molecular Basis of Disease 2018; 1864 (4):1401-1409
- Ryu JH et al. Spectrum of Disorders Associated with Elevated Serum IgG4
Levels Encountered in Clinical Practice.International Journal of Rheumatology
Volume 2012, ID 232960,
Last edited 06/2020