title: Growth of human malaria parasites in biotinylated erythrocytes.
abstract: The adaptation of the biotin-avidin system for the analysis of membrane pathobiology in Plasmodium falciparum malaria is described. Biotin was linked covalently via the succinimide ester derivative (biotinyl-N-hydroxysuccinimide ester, BNHS) to intact human erythrocytes, prior to inoculation and in vitro cultivation of falciparum parasites. Growth experiments indicated that incubation concentrations of less than 1.0 mg BNHS/1.0 ml erythrocyte packed cell volume could yield biotinylated erythrocytes capable of sustaining parasite growth at levels comparable to control cultures. Using a synthesized [14C]BNHS compound at optimal incubation concentration, it was determined that 1.32 X 10(-4) mmol [14C]BNHS were bound per 1.0 mg of erythrocyte stromal protein. In addition, analysis of [14C]biotinylated red blood cell ghost preparations by polyacrylamide gel electrophoresis demonstrated that band 3 (a heterogeneous glycoprotein) was the principal site of membrane labeling. Approximately 77% of total membrane-associated [14C]BNHS was localized to this polypeptide. The unique properties of the specific, ligand-protein interaction of the biotin-avidin complex suggest that the biotinylation procedure described in this report will provide a useful analytical tool in host cell-plasmodial parasite, membrane studies.
mesh_terms: D000818:Animals; D001710:Biotin / Q000031:analogs & derivatives* / Q000378:metabolism; D004910:Erythrocyte Membrane / Q000378:metabolism; D004912:Erythrocytes / Q000469:parasitology*; D006384:Hemagglutination; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism; D010963:Plasmodium falciparum / Q000254:growth & development*; D013388:Succinimides
chemical_list: D008565:Membrane Proteins; D013388:Succinimides; C033788:biotinyl N-hydroxysuccinimide ester; D001710:Biotin