Incomplete Freund's adjuvant enhances locomotor performance following spinal cord injury

Following spinal cord injury (SCI), the pathological sequelae which ensue through the secondary mechanisms of degeneration produce myelin deposits which are potent inhibitors of endogenous neuroregeneration. We have enhanced the immune-mediated response following a hemisection lesion by immunizing adult C57Bl/6 female mice against the inhibitor of neurite outgrowth Nogo-A(623-640) peptide. Moderate anti-Nogo-A(623-640) antibody titre levels were obtained by using Montanide as the adjuvant. However, this antibody response was not obtained using incomplete Freund's adjuvant (IFA). Significant benefit in locomotor performance was demonstrated only in animals which were vaccinated with IFA and not with Montanide. No further benefit could be demonstrated with the Nogo-A(623-640) peptide beyond that seen for adjuvant alone. These data imply that generating antibodies against Nogo-A(623-640) in vivo alone is not sufficient to enhance locomotor recovery and that subcutaneous injection of IFA prior to SCI can enhance locomotor performance.