title: Liposomes and blood cells: a flow cytometric study.
abstract: To clarify the interactions of liposomes with blood cells, this study examined the behaviour of liposomes of a range of compositions in the presence of purified human blood cells in buffer or plasma; or in whole blood, or in mice in vivo. Liposomes, labeled with the hydrophilic fluorochrome, carboxy fluorescein (CF), or with membrane-sequestering R18 or FITC-labeled phospholipids, were mixed with blood cells and the appearance of the fluorochromes in the blood cell population was monitored by flow cytometry. Irrespective of composition, with or without poly(ethylene glycol), all types of liposomes were found to interact rapidly and dose-dependently with red cells, leukocytes and platelets, both in vitro and in vivo. This took place equally in the presence and the absence of plasma proteins and functional enzyme cascades, suggesting that the prime facie interaction is opsonization-independent and is consistent with liposome-blood cell fusion.
authors.affiliation: Canadian Blood Services, Research & Development, c/o Department of Pathology, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Iren
authors.initials: I
authors.lastname: Constantinescu
authors.forename: Elena
authors.initials: E
authors.lastname: Levin
authors.forename: Maria
authors.initials: M
authors.lastname: Gyongyossy-Issa
mesh_terms: D000327:Adsorption; D000818:Animals; D001773:Blood Cells / Q000378:metabolism*; D001792:Blood Platelets / Q000378:metabolism; D002021:Buffers; D016503:Drug Delivery Systems / Q000379:methods*; D005434:Flow Cytometry; D005456:Fluorescent Dyes; D006801:Humans; D008081:Liposomes / Q000737:chemistry* / Q000493:pharmacokinetics*; D051379:Mice; D010949:Plasma
chemical_list: D002021:Buffers; D005456:Fluorescent Dyes; D008081:Liposomes