title: Flow cytometry detection of surface antigens on fresh, unfixed red blood cells infected by Plasmodium falciparum.
abstract: The immunofluorescence detection of parasite-specific antigens on the surface of red blood cells infected by Plasmodium falciparum parasites is usually performed by visual detection under a fluorescence microscope. We describe here a technique permitting the analysis of surface immunofluorescence labelling by flow cytometry. Infected red blood cells are selected on the basis of their parasitic DNA and RNA content by Hoechst and Thiazole Orange vital dyes. Cytometric analysis of these labels, as well as general erythrocyte characteristics assessed by analysis of forward and side scatter allows the selection of viable intact infected erythrocytes from other blood cells. The integrity of these selected erythrocytes was confirmed by the absence of labelling with antibodies directed against internal components such as spectrin. This technique permits the detection of specific surface immunofluorescence staining on red blood cells infected with mature stages of P. falciparum by antibodies in sera from hyperimmune Saimiri monkeys. Using Thiazole Orange dye for detection of parasitised cells, this analysis was performed on a FACSscan apparatus equipped with a single laser.
authors.affiliation: Unité de Parasitologie Expérimentale, Institut Pasteur, Paris, France.
authors.forename: H
authors.initials: H
authors.lastname: Jouin
authors.forename: Y O
authors.initials: YO
authors.lastname: Goguet de la Salmonière
authors.forename: C
authors.initials: C
authors.lastname: Behr
authors.forename: M
authors.initials: M
authors.lastname: Huyin Qan Dat
authors.forename: J C
authors.initials: JC
authors.lastname: Michel
authors.forename: J L
authors.initials: JL
authors.lastname: Sarthou
authors.forename: L
authors.initials: L
authors.lastname: Pereira da Silva
authors.forename: P
authors.initials: P
authors.lastname: Dubois
mesh_terms: D000328:Adult; D000818:Animals; D000913:Antibodies, Protozoan / Q000276:immunology; D000953:Antigens, Protozoan / Q000097:blood*; D000954:Antigens, Surface / Q000097:blood*; D001562:Benzimidazoles; D052160:Benzothiazoles; D002478:Cells, Cultured; D016054:DNA, Protozoan / Q000097:blood; D004912:Erythrocytes / Q000276:immunology / Q000469:parasitology*; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D006801:Humans; D010963:Plasmodium falciparum / Q000276:immunology* / Q000302:isolation & purification; D011804:Quinolines; D016053:RNA, Protozoan / Q000097:blood; D012453:Saimiri; D013844:Thiazoles
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D000954:Antigens, Surface; D001562:Benzimidazoles; D052160:Benzothiazoles; D016054:DNA, Protozoan; D011804:Quinolines; D016053:RNA, Protozoan; D013844:Thiazoles; C051000:thiazole orange; C017807:bisbenzimide ethoxide trihydrochloride