Intravenous Immunoglobulin Expands Regulatory T Cells in Autoimmune Rheumatic Disease

Abstract

To the Editor: Intravenous immunoglobulin (IVIG) therapy can benefit diverse autoimmune and inflammatory diseases through several mutually nonexclusive mechanisms1,2. In vitro and in vivo studies in experimental models have also demonstrated that IVIG can expand CD4+CD25+ regulatory T cells (Treg), the cells that play a critical role in maintaining immune tolerance3,4. Treg maintain immune tolerance by suppressing the activation and function of both innate and adaptive immune cells, while deficiency of Treg is associated with autoimmune and inflammatory conditions5,6. Since IVIG therapy in autoimmune patients is associated with restoration of immune tolerance, we hypothesized that this effect of IVIG is in part through expansion of … Address correspondence to Dr. Bayry, INSERM U872, Equipe 16-Centre de Recherche des Cordeliers, 15 rue de l’Ecole de Medecine, Paris, F-75006, France; E-mail: jagadeesh.bayry{at}crc.jussieu.fr