Immunomodulation of acute spinal cord injury may inhibit the activity of specific inflammatory cascades and result in recovery of motor function. In this study, evaluation of the protective effect of a well-known anti-inflammatory immunomodulator, immunoglobulin G (IgG), was conducted in rats after a 50 g/cm contusion spinal cord injury. Following injury, 400 mg/kg of IgG was administered to the treatment group. Twenty-four hours later, animals were assessed functionally via an inclined plane and the Basso-Beattie-Bresnahan motor scale and compared to controls. Tissue was reviewed for myeloperoxidase activiy (MPO) and lipid peroxidation (LPO), and electron microscopy was conducted to assess tissue ultrastructure. Significant functional preservation was observed in the IgG treatment group. In addition, biochemical assays revealed decreased MPO activity, and electron Microscopic views of tissue showed preserved ultrastructure. IgG treatment following acute contusion injury to the rat spinal cord confers functional and structural neuroprotection. (c) 2008 Elsevier Ltd. All rights reserved.