Quinolinic acid immunoreactive cells in the choroid plexus, leptomeninges and brain vasculature of the immune-stimulated gerbil

Antibodies to quinolinic acid were utilized to study the cellular localization of this endogenous neurotoxin in the gerbil brain subsequent to systemic immune stimulation with pokeweed mitogen. Immunohistochemistry of carbodiimide fixed spleen revealed a dramatic increase in the number of quinolinic acid-positive cells in the red pulp in the immune-stimulated animals. Quinolinic acid immunoreactivity in the brain was observed in cells within the choroid plexus, vasculature and leptomeninges of the stimulated group only. No immunoreactivity was observed in brain parenchyma. These results are supportive of an immune system origin for the increases in quinolinic acid in CSF and brain during immune stimulation in a rodent model system.