Central axonal regeneration and autoimmunity in adult birds

After traumatic lesion adult cock spinal cord displays lively axonal regenerative activity. After 22 days, morphological regeneration regresses; functional regeneration is never observed. Before and after spinal lesion in the cocks, IgG decoration of myelin sheaths is never observed. The sera of both injured and intact animals tested both by immunohistochemical methods on intact spinal cord sections and by immunoelectrophoresis on a protein extract of homologous spinal cord are always negative. The authors suggest that the absence in Birds of any autoimmune response against c.n.s. antigens after surgical exposition, as observed in Mammals, is possibly related to the capacity of the central axons to regenerate in Birds, as observed by the Authors in Amphibia and Reptilia (Triturus and Lacerta).