Polymerized liposomes as stable oxygen‐carriers

FEBS Letters

Chapman, Dennis²  Neufeld, Lawrence¹  Levine, Daniel M.¹  Johnston, David S.²  Simon, Sanford R.¹  Hayward, James A.¹ 

[1] Department of Biochemistry, State University of New York at Stony Brook, Stony Brook, New York 11794, USA;Department of Biochemistry and Chemistry, Royal Free Hospital School of Medicine (University of London), Rowland Hill Street, London NW3 2PF, England

关键词: Phospholipid polymer;    Liposome;    Hemoglobin;    Oxygen transport;    Blood substitute;    Hemosome;   

DOI  :  10.1016/0014-5793(85)81255-2

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

We have produced a surrogate erythrocyte (‘hemosomes’) by encapsulating human hemoglobin in polymerized vesicles composed of diacetylenic phospholipids plus or minus cholesterol. Hemoglobin (in the presence or absence of allosteric effectors) was encapsulated by a freeze-thaw method in large, unilamellar vesicles composed of monomeric lipids. Entrapment was demonstrated by molecular-sieve chromatography. Brief irradiation with ultraviolet light produced polymeric hemosomes with polymerization kinetics and conversions similar to liposomes in the absence of protein. Photo-induced oxidation of the heme was eliminated or severly limited by a combination of prior ligation with CO and the maintenance of high intravesicular hemoglobin concentrations (5–10 mM internal hemoglobin). The inclusion of allosteric effectors within polymerized hemosomes facilitated near-quantitative conversion to the oxy-HbA form. Gas permeability of monomeric and polymeric hemosomes was demonstrated by spectroscopic methods. Reversible spectral shifts, corresponding to oxygenation-deoxygenation, were obtained after brief evacuation and exposure to oxygen or nitrogen. The gas permeability of polymerized hemosomes appears sufficient for the vesicles to act as oxygen carriers in vivo, a notion that is strengthened by their apparent hemocompatibility.

【 授权许可】

Unknown