Preventing adsorption of immunoglobulin G to solid surfaces using poloxamer 407 eliminates artifactual stimulation of neutrophils.

To study the effect of polyclonal intravenous immunoglobulin G (IVIG) on neutrophils in vitro, adsorption of immunoglobulin G (IgG) to solid surfaces has to be prevented, because IgG bound to a solid surface can activate neutrophils through activating FcγRs. In this study we demonstrate that poloxamer 407, a non ionic surfactant, at low concentration (0.05%) prevented the adsorption of high concentrations of IgG (5 mg/ml) better than other blocking agents without interfering with the interaction of IgG with the neutrophils. Poloxamer 407 is therefore a suitable blocking agent to prevent the interaction of immunoglobulin with solid surfaces in cell-based in vitro experiments.