Hayward J A, Levine D M, Neufeld L, Simon S R, Johnston D S, Chapman D
FEBS Lett. 1985 Aug 5;187(2):261-6. doi: 10.1016/0014-5793(85)81255-2.
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 severely 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.
我们通过将人血红蛋白包裹在由二乙炔磷脂加或减胆固醇组成的聚合囊泡中，制备了一种替代红细胞（“血体”）。血红蛋白（在存在或不存在变构效应剂的情况下）通过冻融法包裹在由单体脂质组成的大单层囊泡中。通过分子筛色谱法证明了包封情况。用紫外光短暂照射产生了聚合血体，其聚合动力学和转化率与不存在蛋白质时的脂质体相似。通过预先与一氧化碳结合以及维持高囊泡内血红蛋白浓度（5-10 mM内部血红蛋白）的组合，消除或严重限制了血红素的光诱导氧化。在聚合血体内包含变构效应剂有助于几乎定量地转化为氧合-HbA形式。通过光谱方法证明了单体和聚合血体的气体渗透性。在短暂抽空并暴露于氧气或氮气后，获得了与氧合-脱氧相对应的可逆光谱位移。聚合血体的气体渗透性似乎足以使囊泡在体内充当氧载体，这一观点因其明显的血液相容性而得到加强。
