Significance of brain-reactive antibodies in serum of aged mice.

The possible role of damaged neurons as an antigenic stimulant in the formation of brain reactive antibodies (BRA) has been studied. When neurons of the ventral horn of the spinal cord were damaged by axonal injury, the damaged cells showed no evidence of antigen-antibody reaction within 12 weeks, nor could BRA be demonstrated in the blood during that time in young mice. The possible migration of radio-labeled gamma-globulin across the blood-brain-barrier (BBB) has also been investigated in young mice. Only a very low rate of migration has been observed across the BBB and this might account for the scattered loss of nerve cells in the brains of old animals.