ANTIBODIES TO QUINOLINIC ACID REVEAL LOCALIZATION IN SELECT IMMUNE CELLS RATHER THAN NEURONS OR ASTROGLIA

Polyclonal antibodies were produced against quinolinic acid. No immuno reactivity was observed in any cell type in carbodiimide-fixed brain t issue from control rats. When the antibodies were applied to carbodiim ide-fixed spleen tissue, strong quinolinic acid immunoreactivity was o bserved in some cells with the appearance of macrophages and dendritic cells. These findings indicate an immune system origin for quinolinic acid, and implicate immune cells in excitotoxic CNS pathologies. Thes e findings also raise the possibility that quinolinic acid is a unique cytokine in immune system signal transmission.