Indirect inhibition of in vivo and in vitro T-cell responses by intravenous immunoglobulins due to impaired antigen presentation.

Abstract

Several clinical studies done with intravenous immunoglobulin (IVIg)-treated autoimmune patients as well as several in vitro studies have revealed that IVIg can reduce polyclonal T-cell activation and modify their cytokine secretion pattern. However, their effect on (auto)antigen-specific T-cell responses has never been addressed directly. In the present work, we used an in vivo model of induction of antigen-specific T-cell responses and an in vitro antigen presentation system to study the effects of IVIg on T-cell responses. The results obtained showed that IVIg inhibited both the in vivo and in vitro antigen-specific T-cell responses but that this effect was the indirect consequence of a reduction in the antigen presentation ability of antigen-presenting cells. The inhibitory effect of IVIg was FcgammaRIIb-independent, suggesting that IVIg must interfere with activating FcgammaRs expressed on antigen-presenting cells to reduce their ability to present antigens. Such inhibition of T-cell responses by reducing antigen presentation may therefore contribute to the well-known anti-inflammatory effects of IVIg in autoimmune diseases.

• Authors: Eric Aubin, Réal Lemieux, Renée Bazin
• Journal: Blood (Blood) Vol. 115 Issue 9 Pg. 1727-34 (Mar 04 2010) ISSN: 1528-0020 [Electronic] United States
• PMID: 19965673 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antigen-Antibody Complex
• CPG-oligonucleotide
• Fcgr2b protein, mouse
• Immunoglobulins, Intravenous
• Oligodeoxyribonucleotides
• Receptors, IgG
• Ovalbumin

Topics

• Adoptive Transfer
• Animals
• Antigen Presentation
• Antigen-Antibody Complex (metabolism)
• B-Lymphocytes (immunology)
• Base Sequence
• Binding, Competitive
• Female
• Humans
• Immunoglobulins, Intravenous (administration & dosage)
• In Vitro Techniques
• Mice
• Mice, Inbred BALB C
• Mice, Knockout
• Mice, Transgenic
• Oligodeoxyribonucleotides (administration & dosage, genetics, immunology)
• Ovalbumin (administration & dosage, immunology)
• Receptors, IgG (metabolism)
• T-Lymphocytes (immunology)