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Updated: Jul 16, 2026
04:47
A Method to Assess Fc-mediated Effector Functions Induced by Influenza Hemagglutinin Specific Antibodies
Published on: February 23, 2018
Protein Fv: an endogenous immunoglobulin superantigen and superallergen
Jean-Pierre Bouvet1, Gianni Marone
1Department of Clinical Immunology and Allergy, Center for Basic and Clinical Immunology Research (CISI), University of Naples Federico II, School of Medicine, Naples, Italy.
Chemical Immunology and Allergy
|March 21, 2007
Summary
Protein Fv, an endogenous immunoglobulin superantigen, is elevated in viral hepatitis and activates immune cells. This discovery reveals a new pathway for tissue injury in hepatitis patients.
Area of Science:
- Immunology
- Hepatology
- Virology
Background:
- Protein Fv is synthesized by the human liver at low concentrations.
- Protein Fv levels increase in biological fluids during viral hepatitis (B or C).
- Protein Fv binds to the variable domain of heavy chains in all human immunoglobulins.
Purpose of the Study:
- To investigate the role of Protein Fv in viral hepatitis pathogenesis.
- To characterize Protein Fv as an endogenous immunoglobulin superantigen and superallergen.
Main Methods:
- Isolation and purification of Protein Fv from patient stool extracts and biological samples.
- Analysis of Protein Fv's binding affinity to human immunoglobulins.
- Assessment of Protein Fv's effect on human basophils and mast cells.
Main Results:
- Protein Fv was successfully isolated and purified.
- Protein Fv exhibits high-affinity binding to human immunoglobulin VH3 family.
- Protein Fv acts as a superallergen, activating basophils and mast cells via IgE VH3+.
Conclusions:
- Protein Fv is an endogenous immunoglobulin superantigen and superallergen.
- Protein Fv activation of immune cells represents a novel pathogenetic cascade in viral hepatitis.
- This cascade involves viral infection, superantigen/superallergen production, and subsequent tissue injury.
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