Effect of immunomodulation with human interferon-beta on early functional recovery from experimental spinal cord injury.

STUDY DESIGN: Electron and light microscopic changes, neutrophil infiltration, and lipid peroxidation in the spinal cord and early neurologic examination were studied in rats.

OBJECTIVE: To examine the effects of immunomodulator treatment with recombinant human interferon-beta after spinal cord contusion injury.

SUMMARY OF BACKGROUND DATA: Immunomodulator treatment with interferon-beta has been the subject of extensive studies, but mainly in relation to multiple sclerosis. Recently, it was reported that interferon-beta possessed significant neuroprotection after experimental transient ischemic stroke. However, to our knowledge, there have been no previous reports about the neuroprotective effect of interferon-beta after spinal cord injury.

METHODS: Rats were randomly allocated into 5 groups. Group 1 was control and after clinical examination, normal spinal cord samples were obtained. Group 2 was introduced 50 g/cm contusion injury. Group 3 was vehicle, immediately after trauma 1 mL of physiologic saline was injected. Group 4 was given 30 mg/kg methylprednisolone sodium succinate intraperitoneally immediately after trauma. Group 5 was given 1 x 10(7) IU interferon-beta immediately and 0.5 x 10(7) IU interferon-beta 4 hours after trauma. Animals were examined by inclined plane and Basso-Beattie-Bresnahan scale 24 hours after trauma. Spinal cord samples obtained following clinical evaluations. Neutrophil infiltration was evaluated by myeloperoxidase activity and lipid peroxidation was estimated by thiobarbituric acid test. Electron and light microscopic results were also performed to determine the effects of interferon-beta on tissue structure.

RESULTS: Interferon-beta treatment improved neurologic outcome, which was supported by decreased myeloperoxidase activity and lipid peroxidation. Electron and light microscopic results also showed preservation of tissue structure in the treatment group.

CONCLUSIONS: Immunomodulator treatment with interferon-beta possesses obvious neuroprotection after acute contusion injury to the rat spinal cord.