title: Enhanced fluorescence in indirect immunophenotyping by the use of fluorescent liposomes.
abstract: Small unilamellar liposomes were optimised for cell phenotyping by indirect immunofluorescence. This involved selection and covalent attachment to the liposome of a polyspecific ligand for cell-bound antibody. For this purpose sheep anti-mouse antibody was preferred to protein A because of its ability to attach to cell-bound IgG1 as well as IgG2 at physiological pH. The maximally fluorescent concentration of encapsulated carboxyfluorescein was determined to be 20 mM and liposomes thus comprised gave up to a nine-fold increase in mean cell fluorescence when compared with sheep anti-mouse antibody conjugated to fluorescein isothiocyanate. There was no parallel increase in background fluorescence. Liposomes retained their targeting and fluorescence properties after 3 months storage. They could be sterilised and were as versatile in use as FITC-antibody conjugates.
authors.affiliation: Department of Clinical Haematology, UCMSM, London, U.K.
authors.forename: A G
authors.initials: AG
authors.lastname: Gray
authors.forename: J
authors.initials: J
authors.lastname: Morgan
authors.forename: D C
authors.initials: DC
authors.lastname: Linch
authors.forename: E R
authors.initials: ER
authors.lastname: Huehns
mesh_terms: D000818:Animals; D005434:Flow Cytometry; D016650:Fluorescein-5-isothiocyanate; D005452:Fluoresceins / Q000008:administration & dosage; D005455:Fluorescent Antibody Technique; D006801:Humans; D008081:Liposomes; D051379:Mice; D010641:Phenotype; D012756:Sheep; D013861:Thiocyanates
chemical_list: D005452:Fluoresceins; D008081:Liposomes; D013861:Thiocyanates; C024098:6-carboxyfluorescein; D016650:Fluorescein-5-isothiocyanate