Context
Intravenous immunoglobulin (IVIG) is commonly used to treat auto-immune diseases and systemic inflammatory diseases. IVIG contains normal IgG molecules and is prepared from the pooled plasmas of healthy donors. High doses of IVIG therapy have been shown to have anti-inflammatory effects [1, 2].
Basophils are a type of white blood cells that are responsible for inflammatory reactions during the immune response, and also produce inflammatory mediators such as histamine and serotonin. Recently, it has been reported that, in autoimmune and systemic inflammatory disease models, the anti-inflammatory effects of IVIG are mediated through basophils [3].
The objective of this study was to evaluate the effect of IVIG on human basophil functions. Briefly, circulating basophils were isolated from healthy donors and cultured in the presence of several cytokines and IVIG. The effects of IVIG were evaluated based on several inflammatory biomarkers, including histamine release. The effects of IVIG were first examined on resting basophils, but no effects were found, which indicates that resting basophils are not the target for IVIG. Then, the effects of IVIG were investigated on basophils that were stimulated with IL-3 (interleukine-3), the major basophil-priming cytokine [4]. The Bertin Bioreagent Histamine ELISA kit (Bertin Bioreagent, Montigny-le-Bretonneux, France) was used to measure histamine levels in culture supernatants of IL-3-primed human basophils.
