Ferrous ions and reactive oxygen species increase antigen-binding and anti-inflammatory activities of immunoglobulin G.

Abstract

Polyspecific antibodies represent a first line of defense against infection and regulate inflammation, properties hypothesized to rely on their ability to interact with multiple antigens. We demonstrated that IgG exposure to pro-oxidative ferrous ions or to reactive oxygen species enhances paratope flexibility and hydrophobicity, leading to expansion of the spectrum of recognized antigens, regulation of cell proliferation, and protection in experimental sepsis. We propose that ferrous ions, released from transferrin and ferritin at sites of inflammation, synergize with reactive oxygen species to modify the immunoglobulins present in the surrounding microenvironment, thus quenching pro-inflammatory signals, while facilitating neutralization of pathogens.

• Authors: Jordan D Dimitrov, Nina D Ivanovska, Sébastien Lacroix-Desmazes, Virjinia R Doltchinkova, Srinivas V Kaveri, Tchavdar L Vassilev
• Journal: The Journal of biological chemistry (J Biol Chem) Vol. 281 Issue 1 Pg. 439-46 (Jan 06 2006) ISSN: 0021-9258 [Print] United States
• PMID: 16246843 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Immunoglobulin G
• Reactive Oxygen Species
• Iron

Topics

• Animals
• Antibody Specificity (physiology)
• Antigen-Antibody Reactions (physiology)
• Humans
• Hydrophobic and Hydrophilic Interactions
• Immunoglobulin G (chemistry, immunology, metabolism)
• Inflammation (immunology, metabolism)
• Iron (immunology, metabolism)
• Kinetics
• Mice
• Protein Conformation
• Reactive Oxygen Species (immunology, metabolism)
• Thermodynamics