CELLULAR IMMUNE-REACTIONS DIRECTED AGAINST TOXOPLASMA-GONDII WITH SPECIAL EMPHASIS ON THE CENTRAL-NERVOUS-SYSTEM

Toxoplasma gondii is an obligate intracellular parasite which, after p rimary infection of humans, is maintained in a dormant state by the ho st cellular immune system. In the event of an acquired immunosuppressi on, those parasites surviving as dormant cysts in the host may undergo a change in status, proliferate and cause a life-threatening toxoplas mic encephalitis. Over the last decade much knowlege has accumulated c oncerning the immune response against T. gondii. This review focuses a ttention particularly on the anti-parasitic effector mechanisms and th e cellular immune reactions in the central nervous system during the c ourse of reactivated toxoplasmic encephalitis.