Abstract
An immunoperoxidase antibody (IPA) technique is described for the detection of exoerythrocytic (EE) stages of Plasmodium berghei in rat liver sections or cultured WI38 cells. EE stages were detected in liver sections 12 hours after inoculation of sporozoites, but as early as three hours after the inoculation of WI38 cells. By 42 hours in liver sections and 48 hours in WI38 cells, EE parasites were easily visible by low power microscopy, and merozoites were clearly seen by 72 hours within EE parasites in WI38 cells, or extracellularly on adjacent cells.