title: Identification and localization of a soluble antigen, Ag2, of 136 kDa from Plasmodium falciparum in vitro cultures.
abstract: The soluble antigens, antigen 2 (Ag2) and antigen 6 (Ag6), were copurified from supernatants of P. falciparum in vitro cultures by affinity chromatography and Fast Protein Liquid Chromatography. Rabbit antibodies to Ag2 were raised and characterized by crossed immunoelectrophoresis. Ag2 appeared as a duplet with molecular masses of 136 and 120 kDa when tested by immunoblotting. Immunoprecipitation experiments on Triton X-100 extracted antigens from synchronized cultures showed that the antigen was synthesized in the schizont stage. Ag2 was located near the surface of schizonts in the parasitophorous vacuole and in clefts in the infected erythrocyte cytoplasma as shown by immunogold electron microscopy.
authors.affiliation: Treponematoses Department, Statens Seruminstitut, Copenhagen, Denmark.
authors.forename: P H
authors.initials: PH
authors.lastname: Jakobsen
authors.forename: P
authors.initials: P
authors.lastname: Grellier
authors.forename: T G
authors.initials: TG
authors.lastname: Theander
authors.forename: N
authors.initials: N
authors.lastname: Behrendt
authors.forename: M
authors.initials: M
authors.lastname: Torii
authors.forename: M
authors.initials: M
authors.lastname: Aikawa
authors.forename: J
authors.initials: J
authors.lastname: Schrevel
authors.forename: S
authors.initials: S
authors.lastname: Jepsen
mesh_terms: D000328:Adult; D000818:Animals; D000953:Antigens, Protozoan / Q000032:analysis* / Q000276:immunology / Q000302:isolation & purification; D003378:Counterimmunoelectrophoresis; D006801:Humans; D015151:Immunoblotting; D010963:Plasmodium falciparum / Q000276:immunology*; D012995:Solubility
chemical_list: D000953:Antigens, Protozoan