Fidelity assurance mechanisms of the brain with special reference to its immunogenic CNS compartment: their role in aging and aging-associated neurological disease.

The greater longevity of humans over other mammalian species is provided, in large part, by the complex neural circuitry of the brain. Assurance of the integrity of this circuitry is partly provided by its neural plasticity. The brain is also protected from adverse systemic phenomena by the blood-brain and blood-cerebrospinal fluid barriers. However, these barriers do not protect the brain from adverse phenomena that originate within the central nervous system. The brain and immune systems share many analogous characteristics; and an immunogenic compartment of the brain is described here that also has the capacity to assure the integrity of its neural circuits and its autonomy. Finally, the role of this compartment in aging and in aging-dependent diseases is discussed.