A MALARIA HEAT-SHOCK-LIKE DETERMINANT EXPRESSED ON THE INFECTED HEPATOCYTE SURFACE IS THE TARGET OF ANTIBODY-DEPENDENT CELL-MEDIATED CYTOTOXIC MECHANISMS BY NONPARENCHYMAL LIVER-CELLS

Cultured hepatic stages of Plasmodium falciparum and P. yoelii and with a monoclonal antibody recognizing a C‐terminal fragment of the P. falciparum heat‐shock‐like protein (Pfhsp70) revealed that synthesis of this antigen first occurs during intrahepatic development of the parasite, at the two nuclei stage. Using a variety of techniques, including scanning electron microscopy, we observed that this antigenic determinant was expressed on the infected hepatocyte membrane. Its participation in antibody‐dependent cell‐mediated cytotoxicity was investigated. While no effect was obtained with peripheral blood cells, we found that 25% of the schizonts were specifically lysed when using spleen cells at a killer/target ratio of 30/1. More interestingly, with nonparenchymal liver cells, up to 50% of the hepatic parasites disappeared with a killer/target ratio of 10/1. Copyright © 1990 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim